*/
/*
* Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2011, 2014 by Delphix. All rights reserved.
- * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
- * Copyright 2014 Nexenta Systems, Inc. All rights reserved.
+ * Copyright (c) 2012, Joyent, Inc. All rights reserved.
+ * Copyright (c) 2011, 2017 by Delphix. All rights reserved.
+ * Copyright (c) 2014 by Saso Kiselkov. All rights reserved.
+ * Copyright 2015 Nexenta Systems, Inc. All rights reserved.
*/
/*
* A new reference to a cache buffer can be obtained in two
* ways: 1) via a hash table lookup using the DVA as a key,
* or 2) via one of the ARC lists. The arc_read() interface
- * uses method 1, while the internal arc algorithms for
+ * uses method 1, while the internal ARC algorithms for
* adjusting the cache use method 2. We therefore provide two
* types of locks: 1) the hash table lock array, and 2) the
- * arc list locks.
+ * ARC list locks.
*
* Buffers do not have their own mutexes, rather they rely on the
* hash table mutexes for the bulk of their protection (i.e. most
* buf_hash_remove() expects the appropriate hash mutex to be
* already held before it is invoked.
*
- * Each arc state also has a mutex which is used to protect the
+ * Each ARC state also has a mutex which is used to protect the
* buffer list associated with the state. When attempting to
- * obtain a hash table lock while holding an arc list lock you
+ * obtain a hash table lock while holding an ARC list lock you
* must use: mutex_tryenter() to avoid deadlock. Also note that
* the active state mutex must be held before the ghost state mutex.
*
- * Arc buffers may have an associated eviction callback function.
- * This function will be invoked prior to removing the buffer (e.g.
- * in arc_do_user_evicts()). Note however that the data associated
- * with the buffer may be evicted prior to the callback. The callback
- * must be made with *no locks held* (to prevent deadlock). Additionally,
- * the users of callbacks must ensure that their private data is
- * protected from simultaneous callbacks from arc_clear_callback()
- * and arc_do_user_evicts().
- *
* It as also possible to register a callback which is run when the
* arc_meta_limit is reached and no buffers can be safely evicted. In
* this case the arc user should drop a reference on some arc buffers so
* - ARC header release, as it removes from L2ARC buflists
*/
+/*
+ * ARC operation:
+ *
+ * Every block that is in the ARC is tracked by an arc_buf_hdr_t structure.
+ * This structure can point either to a block that is still in the cache or to
+ * one that is only accessible in an L2 ARC device, or it can provide
+ * information about a block that was recently evicted. If a block is
+ * only accessible in the L2ARC, then the arc_buf_hdr_t only has enough
+ * information to retrieve it from the L2ARC device. This information is
+ * stored in the l2arc_buf_hdr_t sub-structure of the arc_buf_hdr_t. A block
+ * that is in this state cannot access the data directly.
+ *
+ * Blocks that are actively being referenced or have not been evicted
+ * are cached in the L1ARC. The L1ARC (l1arc_buf_hdr_t) is a structure within
+ * the arc_buf_hdr_t that will point to the data block in memory. A block can
+ * only be read by a consumer if it has an l1arc_buf_hdr_t. The L1ARC
+ * caches data in two ways -- in a list of ARC buffers (arc_buf_t) and
+ * also in the arc_buf_hdr_t's private physical data block pointer (b_pabd).
+ *
+ * The L1ARC's data pointer may or may not be uncompressed. The ARC has the
+ * ability to store the physical data (b_pabd) associated with the DVA of the
+ * arc_buf_hdr_t. Since the b_pabd is a copy of the on-disk physical block,
+ * it will match its on-disk compression characteristics. This behavior can be
+ * disabled by setting 'zfs_compressed_arc_enabled' to B_FALSE. When the
+ * compressed ARC functionality is disabled, the b_pabd will point to an
+ * uncompressed version of the on-disk data.
+ *
+ * Data in the L1ARC is not accessed by consumers of the ARC directly. Each
+ * arc_buf_hdr_t can have multiple ARC buffers (arc_buf_t) which reference it.
+ * Each ARC buffer (arc_buf_t) is being actively accessed by a specific ARC
+ * consumer. The ARC will provide references to this data and will keep it
+ * cached until it is no longer in use. The ARC caches only the L1ARC's physical
+ * data block and will evict any arc_buf_t that is no longer referenced. The
+ * amount of memory consumed by the arc_buf_ts' data buffers can be seen via the
+ * "overhead_size" kstat.
+ *
+ * Depending on the consumer, an arc_buf_t can be requested in uncompressed or
+ * compressed form. The typical case is that consumers will want uncompressed
+ * data, and when that happens a new data buffer is allocated where the data is
+ * decompressed for them to use. Currently the only consumer who wants
+ * compressed arc_buf_t's is "zfs send", when it streams data exactly as it
+ * exists on disk. When this happens, the arc_buf_t's data buffer is shared
+ * with the arc_buf_hdr_t.
+ *
+ * Here is a diagram showing an arc_buf_hdr_t referenced by two arc_buf_t's. The
+ * first one is owned by a compressed send consumer (and therefore references
+ * the same compressed data buffer as the arc_buf_hdr_t) and the second could be
+ * used by any other consumer (and has its own uncompressed copy of the data
+ * buffer).
+ *
+ * arc_buf_hdr_t
+ * +-----------+
+ * | fields |
+ * | common to |
+ * | L1- and |
+ * | L2ARC |
+ * +-----------+
+ * | l2arc_buf_hdr_t
+ * | |
+ * +-----------+
+ * | l1arc_buf_hdr_t
+ * | | arc_buf_t
+ * | b_buf +------------>+-----------+ arc_buf_t
+ * | b_pabd +-+ |b_next +---->+-----------+
+ * +-----------+ | |-----------| |b_next +-->NULL
+ * | |b_comp = T | +-----------+
+ * | |b_data +-+ |b_comp = F |
+ * | +-----------+ | |b_data +-+
+ * +->+------+ | +-----------+ |
+ * compressed | | | |
+ * data | |<--------------+ | uncompressed
+ * +------+ compressed, | data
+ * shared +-->+------+
+ * data | |
+ * | |
+ * +------+
+ *
+ * When a consumer reads a block, the ARC must first look to see if the
+ * arc_buf_hdr_t is cached. If the hdr is cached then the ARC allocates a new
+ * arc_buf_t and either copies uncompressed data into a new data buffer from an
+ * existing uncompressed arc_buf_t, decompresses the hdr's b_pabd buffer into a
+ * new data buffer, or shares the hdr's b_pabd buffer, depending on whether the
+ * hdr is compressed and the desired compression characteristics of the
+ * arc_buf_t consumer. If the arc_buf_t ends up sharing data with the
+ * arc_buf_hdr_t and both of them are uncompressed then the arc_buf_t must be
+ * the last buffer in the hdr's b_buf list, however a shared compressed buf can
+ * be anywhere in the hdr's list.
+ *
+ * The diagram below shows an example of an uncompressed ARC hdr that is
+ * sharing its data with an arc_buf_t (note that the shared uncompressed buf is
+ * the last element in the buf list):
+ *
+ * arc_buf_hdr_t
+ * +-----------+
+ * | |
+ * | |
+ * | |
+ * +-----------+
+ * l2arc_buf_hdr_t| |
+ * | |
+ * +-----------+
+ * l1arc_buf_hdr_t| |
+ * | | arc_buf_t (shared)
+ * | b_buf +------------>+---------+ arc_buf_t
+ * | | |b_next +---->+---------+
+ * | b_pabd +-+ |---------| |b_next +-->NULL
+ * +-----------+ | | | +---------+
+ * | |b_data +-+ | |
+ * | +---------+ | |b_data +-+
+ * +->+------+ | +---------+ |
+ * | | | |
+ * uncompressed | | | |
+ * data +------+ | |
+ * ^ +->+------+ |
+ * | uncompressed | | |
+ * | data | | |
+ * | +------+ |
+ * +---------------------------------+
+ *
+ * Writing to the ARC requires that the ARC first discard the hdr's b_pabd
+ * since the physical block is about to be rewritten. The new data contents
+ * will be contained in the arc_buf_t. As the I/O pipeline performs the write,
+ * it may compress the data before writing it to disk. The ARC will be called
+ * with the transformed data and will bcopy the transformed on-disk block into
+ * a newly allocated b_pabd. Writes are always done into buffers which have
+ * either been loaned (and hence are new and don't have other readers) or
+ * buffers which have been released (and hence have their own hdr, if there
+ * were originally other readers of the buf's original hdr). This ensures that
+ * the ARC only needs to update a single buf and its hdr after a write occurs.
+ *
+ * When the L2ARC is in use, it will also take advantage of the b_pabd. The
+ * L2ARC will always write the contents of b_pabd to the L2ARC. This means
+ * that when compressed ARC is enabled that the L2ARC blocks are identical
+ * to the on-disk block in the main data pool. This provides a significant
+ * advantage since the ARC can leverage the bp's checksum when reading from the
+ * L2ARC to determine if the contents are valid. However, if the compressed
+ * ARC is disabled, then the L2ARC's block must be transformed to look
+ * like the physical block in the main data pool before comparing the
+ * checksum and determining its validity.
+ *
+ * The L1ARC has a slightly different system for storing encrypted data.
+ * Raw (encrypted + possibly compressed) data has a few subtle differences from
+ * data that is just compressed. The biggest difference is that it is not
+ * possible to decrypt encrypted data (or visa versa) if the keys aren't loaded.
+ * The other difference is that encryption cannot be treated as a suggestion.
+ * If a caller would prefer compressed data, but they actually wind up with
+ * uncompressed data the worst thing that could happen is there might be a
+ * performance hit. If the caller requests encrypted data, however, we must be
+ * sure they actually get it or else secret information could be leaked. Raw
+ * data is stored in hdr->b_crypt_hdr.b_rabd. An encrypted header, therefore,
+ * may have both an encrypted version and a decrypted version of its data at
+ * once. When a caller needs a raw arc_buf_t, it is allocated and the data is
+ * copied out of this header. To avoid complications with b_pabd, raw buffers
+ * cannot be shared.
+ */
+
#include <sys/spa.h>
#include <sys/zio.h>
+#include <sys/spa_impl.h>
#include <sys/zio_compress.h>
+#include <sys/zio_checksum.h>
#include <sys/zfs_context.h>
#include <sys/arc.h>
+#include <sys/refcount.h>
#include <sys/vdev.h>
#include <sys/vdev_impl.h>
#include <sys/dsl_pool.h>
+#include <sys/zio_checksum.h>
#include <sys/multilist.h>
+#include <sys/abd.h>
+#include <sys/zil.h>
+#include <sys/fm/fs/zfs.h>
#ifdef _KERNEL
#include <sys/vmsystm.h>
#include <vm/anon.h>
static boolean_t arc_reclaim_thread_exit;
static kcondvar_t arc_reclaim_waiters_cv;
-static kmutex_t arc_user_evicts_lock;
-static kcondvar_t arc_user_evicts_cv;
-static boolean_t arc_user_evicts_thread_exit;
-
-/* number of objects to prune from caches when arc_meta_limit is reached */
-int zfs_arc_meta_prune = 10000;
-
-/* The preferred strategy to employ when arc_meta_limit is reached */
-int zfs_arc_meta_strategy = ARC_STRATEGY_META_BALANCED;
-
-typedef enum arc_reclaim_strategy {
- ARC_RECLAIM_AGGR, /* Aggressive reclaim strategy */
- ARC_RECLAIM_CONS /* Conservative reclaim strategy */
-} arc_reclaim_strategy_t;
-
/*
* The number of headers to evict in arc_evict_state_impl() before
* dropping the sublist lock and evicting from another sublist. A lower
*/
int zfs_arc_evict_batch_limit = 10;
-/*
- * The number of sublists used for each of the arc state lists. If this
- * is not set to a suitable value by the user, it will be configured to
- * the number of CPUs on the system in arc_init().
- */
-int zfs_arc_num_sublists_per_state = 0;
-
/* number of seconds before growing cache again */
-int zfs_arc_grow_retry = 5;
+static int arc_grow_retry = 5;
-/* shift of arc_c for calculating overflow limit in arc_get_data_buf */
-int zfs_arc_overflow_shift = 8;
-
-/* disable anon data aggressively growing arc_p */
-int zfs_arc_p_aggressive_disable = 1;
+/* shift of arc_c for calculating overflow limit in arc_get_data_impl */
+int zfs_arc_overflow_shift = 8;
-/* disable arc_p adapt dampener in arc_adapt */
-int zfs_arc_p_dampener_disable = 1;
+/* shift of arc_c for calculating both min and max arc_p */
+static int arc_p_min_shift = 4;
/* log2(fraction of arc to reclaim) */
-int zfs_arc_shrink_shift = 5;
+static int arc_shrink_shift = 7;
+
+/* percent of pagecache to reclaim arc to */
+#ifdef _KERNEL
+static uint_t zfs_arc_pc_percent = 0;
+#endif
/*
- * minimum lifespan of a prefetch block in clock ticks
- * (initialized in arc_init())
+ * log2(fraction of ARC which must be free to allow growing).
+ * I.e. If there is less than arc_c >> arc_no_grow_shift free memory,
+ * when reading a new block into the ARC, we will evict an equal-sized block
+ * from the ARC.
+ *
+ * This must be less than arc_shrink_shift, so that when we shrink the ARC,
+ * we will still not allow it to grow.
*/
-int zfs_arc_min_prefetch_lifespan = HZ;
-
-/* disable arc proactive arc throttle due to low memory */
-int zfs_arc_memory_throttle_disable = 1;
+int arc_no_grow_shift = 5;
-/* disable duplicate buffer eviction */
-int zfs_disable_dup_eviction = 0;
-
-/* average block used to size buf_hash_table */
-int zfs_arc_average_blocksize = 8 * 1024; /* 8KB */
/*
* minimum lifespan of a prefetch block in clock ticks
* (initialized in arc_init())
*/
-static int arc_min_prefetch_lifespan;
+static int arc_min_prefetch_lifespan;
/*
* If this percent of memory is free, don't throttle.
static int arc_dead;
-/* expiration time for arc_no_grow */
-static clock_t arc_grow_time = 0;
-
/*
* The arc has filled available memory and has now warmed up.
*/
static boolean_t arc_warm;
+/*
+ * log2 fraction of the zio arena to keep free.
+ */
+int arc_zio_arena_free_shift = 2;
+
/*
* These tunables are for performance analysis.
*/
unsigned long zfs_arc_min = 0;
unsigned long zfs_arc_meta_limit = 0;
unsigned long zfs_arc_meta_min = 0;
+unsigned long zfs_arc_dnode_limit = 0;
+unsigned long zfs_arc_dnode_reduce_percent = 10;
+int zfs_arc_grow_retry = 0;
+int zfs_arc_shrink_shift = 0;
+int zfs_arc_p_min_shift = 0;
+int zfs_arc_average_blocksize = 8 * 1024; /* 8KB */
+
+int zfs_compressed_arc_enabled = B_TRUE;
+
+/*
+ * ARC will evict meta buffers that exceed arc_meta_limit. This
+ * tunable make arc_meta_limit adjustable for different workloads.
+ */
+unsigned long zfs_arc_meta_limit_percent = 75;
+
+/*
+ * Percentage that can be consumed by dnodes of ARC meta buffers.
+ */
+unsigned long zfs_arc_dnode_limit_percent = 10;
/*
- * Limit the number of restarts in arc_adjust_meta()
+ * These tunables are Linux specific
*/
-unsigned long zfs_arc_meta_adjust_restarts = 4096;
+unsigned long zfs_arc_sys_free = 0;
+int zfs_arc_min_prefetch_lifespan = 0;
+int zfs_arc_p_aggressive_disable = 1;
+int zfs_arc_p_dampener_disable = 1;
+int zfs_arc_meta_prune = 10000;
+int zfs_arc_meta_strategy = ARC_STRATEGY_META_BALANCED;
+int zfs_arc_meta_adjust_restarts = 4096;
+int zfs_arc_lotsfree_percent = 10;
/* The 6 states: */
static arc_state_t ARC_anon;
kstat_named_t arcstat_c_min;
kstat_named_t arcstat_c_max;
kstat_named_t arcstat_size;
+ /*
+ * Number of compressed bytes stored in the arc_buf_hdr_t's b_pabd.
+ * Note that the compressed bytes may match the uncompressed bytes
+ * if the block is either not compressed or compressed arc is disabled.
+ */
+ kstat_named_t arcstat_compressed_size;
+ /*
+ * Uncompressed size of the data stored in b_pabd. If compressed
+ * arc is disabled then this value will be identical to the stat
+ * above.
+ */
+ kstat_named_t arcstat_uncompressed_size;
+ /*
+ * Number of bytes stored in all the arc_buf_t's. This is classified
+ * as "overhead" since this data is typically short-lived and will
+ * be evicted from the arc when it becomes unreferenced unless the
+ * zfs_keep_uncompressed_metadata or zfs_keep_uncompressed_level
+ * values have been set (see comment in dbuf.c for more information).
+ */
+ kstat_named_t arcstat_overhead_size;
+ /*
+ * Number of bytes consumed by internal ARC structures necessary
+ * for tracking purposes; these structures are not actually
+ * backed by ARC buffers. This includes arc_buf_hdr_t structures
+ * (allocated via arc_buf_hdr_t_full and arc_buf_hdr_t_l2only
+ * caches), and arc_buf_t structures (allocated via arc_buf_t
+ * cache).
+ */
kstat_named_t arcstat_hdr_size;
+ /*
+ * Number of bytes consumed by ARC buffers of type equal to
+ * ARC_BUFC_DATA. This is generally consumed by buffers backing
+ * on disk user data (e.g. plain file contents).
+ */
kstat_named_t arcstat_data_size;
- kstat_named_t arcstat_meta_size;
- kstat_named_t arcstat_other_size;
+ /*
+ * Number of bytes consumed by ARC buffers of type equal to
+ * ARC_BUFC_METADATA. This is generally consumed by buffers
+ * backing on disk data that is used for internal ZFS
+ * structures (e.g. ZAP, dnode, indirect blocks, etc).
+ */
+ kstat_named_t arcstat_metadata_size;
+ /*
+ * Number of bytes consumed by dmu_buf_impl_t objects.
+ */
+ kstat_named_t arcstat_dbuf_size;
+ /*
+ * Number of bytes consumed by dnode_t objects.
+ */
+ kstat_named_t arcstat_dnode_size;
+ /*
+ * Number of bytes consumed by bonus buffers.
+ */
+ kstat_named_t arcstat_bonus_size;
+ /*
+ * Total number of bytes consumed by ARC buffers residing in the
+ * arc_anon state. This includes *all* buffers in the arc_anon
+ * state; e.g. data, metadata, evictable, and unevictable buffers
+ * are all included in this value.
+ */
kstat_named_t arcstat_anon_size;
- kstat_named_t arcstat_anon_evict_data;
- kstat_named_t arcstat_anon_evict_metadata;
+ /*
+ * Number of bytes consumed by ARC buffers that meet the
+ * following criteria: backing buffers of type ARC_BUFC_DATA,
+ * residing in the arc_anon state, and are eligible for eviction
+ * (e.g. have no outstanding holds on the buffer).
+ */
+ kstat_named_t arcstat_anon_evictable_data;
+ /*
+ * Number of bytes consumed by ARC buffers that meet the
+ * following criteria: backing buffers of type ARC_BUFC_METADATA,
+ * residing in the arc_anon state, and are eligible for eviction
+ * (e.g. have no outstanding holds on the buffer).
+ */
+ kstat_named_t arcstat_anon_evictable_metadata;
+ /*
+ * Total number of bytes consumed by ARC buffers residing in the
+ * arc_mru state. This includes *all* buffers in the arc_mru
+ * state; e.g. data, metadata, evictable, and unevictable buffers
+ * are all included in this value.
+ */
kstat_named_t arcstat_mru_size;
- kstat_named_t arcstat_mru_evict_data;
- kstat_named_t arcstat_mru_evict_metadata;
+ /*
+ * Number of bytes consumed by ARC buffers that meet the
+ * following criteria: backing buffers of type ARC_BUFC_DATA,
+ * residing in the arc_mru state, and are eligible for eviction
+ * (e.g. have no outstanding holds on the buffer).
+ */
+ kstat_named_t arcstat_mru_evictable_data;
+ /*
+ * Number of bytes consumed by ARC buffers that meet the
+ * following criteria: backing buffers of type ARC_BUFC_METADATA,
+ * residing in the arc_mru state, and are eligible for eviction
+ * (e.g. have no outstanding holds on the buffer).
+ */
+ kstat_named_t arcstat_mru_evictable_metadata;
+ /*
+ * Total number of bytes that *would have been* consumed by ARC
+ * buffers in the arc_mru_ghost state. The key thing to note
+ * here, is the fact that this size doesn't actually indicate
+ * RAM consumption. The ghost lists only consist of headers and
+ * don't actually have ARC buffers linked off of these headers.
+ * Thus, *if* the headers had associated ARC buffers, these
+ * buffers *would have* consumed this number of bytes.
+ */
kstat_named_t arcstat_mru_ghost_size;
- kstat_named_t arcstat_mru_ghost_evict_data;
- kstat_named_t arcstat_mru_ghost_evict_metadata;
+ /*
+ * Number of bytes that *would have been* consumed by ARC
+ * buffers that are eligible for eviction, of type
+ * ARC_BUFC_DATA, and linked off the arc_mru_ghost state.
+ */
+ kstat_named_t arcstat_mru_ghost_evictable_data;
+ /*
+ * Number of bytes that *would have been* consumed by ARC
+ * buffers that are eligible for eviction, of type
+ * ARC_BUFC_METADATA, and linked off the arc_mru_ghost state.
+ */
+ kstat_named_t arcstat_mru_ghost_evictable_metadata;
+ /*
+ * Total number of bytes consumed by ARC buffers residing in the
+ * arc_mfu state. This includes *all* buffers in the arc_mfu
+ * state; e.g. data, metadata, evictable, and unevictable buffers
+ * are all included in this value.
+ */
kstat_named_t arcstat_mfu_size;
- kstat_named_t arcstat_mfu_evict_data;
- kstat_named_t arcstat_mfu_evict_metadata;
+ /*
+ * Number of bytes consumed by ARC buffers that are eligible for
+ * eviction, of type ARC_BUFC_DATA, and reside in the arc_mfu
+ * state.
+ */
+ kstat_named_t arcstat_mfu_evictable_data;
+ /*
+ * Number of bytes consumed by ARC buffers that are eligible for
+ * eviction, of type ARC_BUFC_METADATA, and reside in the
+ * arc_mfu state.
+ */
+ kstat_named_t arcstat_mfu_evictable_metadata;
+ /*
+ * Total number of bytes that *would have been* consumed by ARC
+ * buffers in the arc_mfu_ghost state. See the comment above
+ * arcstat_mru_ghost_size for more details.
+ */
kstat_named_t arcstat_mfu_ghost_size;
- kstat_named_t arcstat_mfu_ghost_evict_data;
- kstat_named_t arcstat_mfu_ghost_evict_metadata;
+ /*
+ * Number of bytes that *would have been* consumed by ARC
+ * buffers that are eligible for eviction, of type
+ * ARC_BUFC_DATA, and linked off the arc_mfu_ghost state.
+ */
+ kstat_named_t arcstat_mfu_ghost_evictable_data;
+ /*
+ * Number of bytes that *would have been* consumed by ARC
+ * buffers that are eligible for eviction, of type
+ * ARC_BUFC_METADATA, and linked off the arc_mru_ghost state.
+ */
+ kstat_named_t arcstat_mfu_ghost_evictable_metadata;
kstat_named_t arcstat_l2_hits;
kstat_named_t arcstat_l2_misses;
kstat_named_t arcstat_l2_feeds;
kstat_named_t arcstat_l2_evict_reading;
kstat_named_t arcstat_l2_evict_l1cached;
kstat_named_t arcstat_l2_free_on_write;
- kstat_named_t arcstat_l2_cdata_free_on_write;
kstat_named_t arcstat_l2_abort_lowmem;
kstat_named_t arcstat_l2_cksum_bad;
kstat_named_t arcstat_l2_io_error;
- kstat_named_t arcstat_l2_size;
- kstat_named_t arcstat_l2_asize;
+ kstat_named_t arcstat_l2_lsize;
+ kstat_named_t arcstat_l2_psize;
kstat_named_t arcstat_l2_hdr_size;
- kstat_named_t arcstat_l2_compress_successes;
- kstat_named_t arcstat_l2_compress_zeros;
- kstat_named_t arcstat_l2_compress_failures;
kstat_named_t arcstat_memory_throttle_count;
- kstat_named_t arcstat_duplicate_buffers;
- kstat_named_t arcstat_duplicate_buffers_size;
- kstat_named_t arcstat_duplicate_reads;
kstat_named_t arcstat_memory_direct_count;
kstat_named_t arcstat_memory_indirect_count;
+ kstat_named_t arcstat_memory_all_bytes;
+ kstat_named_t arcstat_memory_free_bytes;
+ kstat_named_t arcstat_memory_available_bytes;
kstat_named_t arcstat_no_grow;
kstat_named_t arcstat_tempreserve;
kstat_named_t arcstat_loaned_bytes;
kstat_named_t arcstat_prune;
kstat_named_t arcstat_meta_used;
kstat_named_t arcstat_meta_limit;
+ kstat_named_t arcstat_dnode_limit;
kstat_named_t arcstat_meta_max;
kstat_named_t arcstat_meta_min;
+ kstat_named_t arcstat_sync_wait_for_async;
+ kstat_named_t arcstat_demand_hit_predictive_prefetch;
+ kstat_named_t arcstat_need_free;
+ kstat_named_t arcstat_sys_free;
+ kstat_named_t arcstat_raw_size;
} arc_stats_t;
static arc_stats_t arc_stats = {
{ "c_min", KSTAT_DATA_UINT64 },
{ "c_max", KSTAT_DATA_UINT64 },
{ "size", KSTAT_DATA_UINT64 },
+ { "compressed_size", KSTAT_DATA_UINT64 },
+ { "uncompressed_size", KSTAT_DATA_UINT64 },
+ { "overhead_size", KSTAT_DATA_UINT64 },
{ "hdr_size", KSTAT_DATA_UINT64 },
{ "data_size", KSTAT_DATA_UINT64 },
- { "meta_size", KSTAT_DATA_UINT64 },
- { "other_size", KSTAT_DATA_UINT64 },
+ { "metadata_size", KSTAT_DATA_UINT64 },
+ { "dbuf_size", KSTAT_DATA_UINT64 },
+ { "dnode_size", KSTAT_DATA_UINT64 },
+ { "bonus_size", KSTAT_DATA_UINT64 },
{ "anon_size", KSTAT_DATA_UINT64 },
- { "anon_evict_data", KSTAT_DATA_UINT64 },
- { "anon_evict_metadata", KSTAT_DATA_UINT64 },
+ { "anon_evictable_data", KSTAT_DATA_UINT64 },
+ { "anon_evictable_metadata", KSTAT_DATA_UINT64 },
{ "mru_size", KSTAT_DATA_UINT64 },
- { "mru_evict_data", KSTAT_DATA_UINT64 },
- { "mru_evict_metadata", KSTAT_DATA_UINT64 },
+ { "mru_evictable_data", KSTAT_DATA_UINT64 },
+ { "mru_evictable_metadata", KSTAT_DATA_UINT64 },
{ "mru_ghost_size", KSTAT_DATA_UINT64 },
- { "mru_ghost_evict_data", KSTAT_DATA_UINT64 },
- { "mru_ghost_evict_metadata", KSTAT_DATA_UINT64 },
+ { "mru_ghost_evictable_data", KSTAT_DATA_UINT64 },
+ { "mru_ghost_evictable_metadata", KSTAT_DATA_UINT64 },
{ "mfu_size", KSTAT_DATA_UINT64 },
- { "mfu_evict_data", KSTAT_DATA_UINT64 },
- { "mfu_evict_metadata", KSTAT_DATA_UINT64 },
+ { "mfu_evictable_data", KSTAT_DATA_UINT64 },
+ { "mfu_evictable_metadata", KSTAT_DATA_UINT64 },
{ "mfu_ghost_size", KSTAT_DATA_UINT64 },
- { "mfu_ghost_evict_data", KSTAT_DATA_UINT64 },
- { "mfu_ghost_evict_metadata", KSTAT_DATA_UINT64 },
+ { "mfu_ghost_evictable_data", KSTAT_DATA_UINT64 },
+ { "mfu_ghost_evictable_metadata", KSTAT_DATA_UINT64 },
{ "l2_hits", KSTAT_DATA_UINT64 },
{ "l2_misses", KSTAT_DATA_UINT64 },
{ "l2_feeds", KSTAT_DATA_UINT64 },
{ "l2_evict_reading", KSTAT_DATA_UINT64 },
{ "l2_evict_l1cached", KSTAT_DATA_UINT64 },
{ "l2_free_on_write", KSTAT_DATA_UINT64 },
- { "l2_cdata_free_on_write", KSTAT_DATA_UINT64 },
{ "l2_abort_lowmem", KSTAT_DATA_UINT64 },
{ "l2_cksum_bad", KSTAT_DATA_UINT64 },
{ "l2_io_error", KSTAT_DATA_UINT64 },
{ "l2_size", KSTAT_DATA_UINT64 },
{ "l2_asize", KSTAT_DATA_UINT64 },
{ "l2_hdr_size", KSTAT_DATA_UINT64 },
- { "l2_compress_successes", KSTAT_DATA_UINT64 },
- { "l2_compress_zeros", KSTAT_DATA_UINT64 },
- { "l2_compress_failures", KSTAT_DATA_UINT64 },
{ "memory_throttle_count", KSTAT_DATA_UINT64 },
- { "duplicate_buffers", KSTAT_DATA_UINT64 },
- { "duplicate_buffers_size", KSTAT_DATA_UINT64 },
- { "duplicate_reads", KSTAT_DATA_UINT64 },
{ "memory_direct_count", KSTAT_DATA_UINT64 },
{ "memory_indirect_count", KSTAT_DATA_UINT64 },
+ { "memory_all_bytes", KSTAT_DATA_UINT64 },
+ { "memory_free_bytes", KSTAT_DATA_UINT64 },
+ { "memory_available_bytes", KSTAT_DATA_INT64 },
{ "arc_no_grow", KSTAT_DATA_UINT64 },
{ "arc_tempreserve", KSTAT_DATA_UINT64 },
{ "arc_loaned_bytes", KSTAT_DATA_UINT64 },
{ "arc_prune", KSTAT_DATA_UINT64 },
{ "arc_meta_used", KSTAT_DATA_UINT64 },
{ "arc_meta_limit", KSTAT_DATA_UINT64 },
+ { "arc_dnode_limit", KSTAT_DATA_UINT64 },
{ "arc_meta_max", KSTAT_DATA_UINT64 },
{ "arc_meta_min", KSTAT_DATA_UINT64 },
+ { "sync_wait_for_async", KSTAT_DATA_UINT64 },
+ { "demand_hit_predictive_prefetch", KSTAT_DATA_UINT64 },
+ { "arc_need_free", KSTAT_DATA_UINT64 },
+ { "arc_sys_free", KSTAT_DATA_UINT64 },
+ { "arc_raw_size", KSTAT_DATA_UINT64 }
};
#define ARCSTAT(stat) (arc_stats.stat.value.ui64)
#define arc_c ARCSTAT(arcstat_c) /* target size of cache */
#define arc_c_min ARCSTAT(arcstat_c_min) /* min target cache size */
#define arc_c_max ARCSTAT(arcstat_c_max) /* max target cache size */
-#define arc_no_grow ARCSTAT(arcstat_no_grow)
+#define arc_no_grow ARCSTAT(arcstat_no_grow) /* do not grow cache size */
#define arc_tempreserve ARCSTAT(arcstat_tempreserve)
#define arc_loaned_bytes ARCSTAT(arcstat_loaned_bytes)
#define arc_meta_limit ARCSTAT(arcstat_meta_limit) /* max size for metadata */
+#define arc_dnode_limit ARCSTAT(arcstat_dnode_limit) /* max size for dnodes */
#define arc_meta_min ARCSTAT(arcstat_meta_min) /* min size for metadata */
#define arc_meta_used ARCSTAT(arcstat_meta_used) /* size of metadata */
#define arc_meta_max ARCSTAT(arcstat_meta_max) /* max size of metadata */
-
-#define L2ARC_IS_VALID_COMPRESS(_c_) \
- ((_c_) == ZIO_COMPRESS_LZ4 || (_c_) == ZIO_COMPRESS_EMPTY)
+#define arc_dbuf_size ARCSTAT(arcstat_dbuf_size) /* dbuf metadata */
+#define arc_dnode_size ARCSTAT(arcstat_dnode_size) /* dnode metadata */
+#define arc_bonus_size ARCSTAT(arcstat_bonus_size) /* bonus buffer metadata */
+#define arc_need_free ARCSTAT(arcstat_need_free) /* bytes to be freed */
+#define arc_sys_free ARCSTAT(arcstat_sys_free) /* target system free bytes */
+
+/* size of all b_rabd's in entire arc */
+#define arc_raw_size ARCSTAT(arcstat_raw_size)
+/* compressed size of entire arc */
+#define arc_compressed_size ARCSTAT(arcstat_compressed_size)
+/* uncompressed size of entire arc */
+#define arc_uncompressed_size ARCSTAT(arcstat_uncompressed_size)
+/* number of bytes in the arc from arc_buf_t's */
+#define arc_overhead_size ARCSTAT(arcstat_overhead_size)
static list_t arc_prune_list;
static kmutex_t arc_prune_mtx;
static taskq_t *arc_prune_taskq;
-static arc_buf_t *arc_eviction_list;
-static arc_buf_hdr_t arc_eviction_hdr;
#define GHOST_STATE(state) \
((state) == arc_mru_ghost || (state) == arc_mfu_ghost || \
#define HDR_IO_IN_PROGRESS(hdr) ((hdr)->b_flags & ARC_FLAG_IO_IN_PROGRESS)
#define HDR_IO_ERROR(hdr) ((hdr)->b_flags & ARC_FLAG_IO_ERROR)
#define HDR_PREFETCH(hdr) ((hdr)->b_flags & ARC_FLAG_PREFETCH)
-#define HDR_FREED_IN_READ(hdr) ((hdr)->b_flags & ARC_FLAG_FREED_IN_READ)
-#define HDR_BUF_AVAILABLE(hdr) ((hdr)->b_flags & ARC_FLAG_BUF_AVAILABLE)
+#define HDR_COMPRESSION_ENABLED(hdr) \
+ ((hdr)->b_flags & ARC_FLAG_COMPRESSED_ARC)
#define HDR_L2CACHE(hdr) ((hdr)->b_flags & ARC_FLAG_L2CACHE)
-#define HDR_L2COMPRESS(hdr) ((hdr)->b_flags & ARC_FLAG_L2COMPRESS)
#define HDR_L2_READING(hdr) \
- (((hdr)->b_flags & ARC_FLAG_IO_IN_PROGRESS) && \
- ((hdr)->b_flags & ARC_FLAG_HAS_L2HDR))
+ (((hdr)->b_flags & ARC_FLAG_IO_IN_PROGRESS) && \
+ ((hdr)->b_flags & ARC_FLAG_HAS_L2HDR))
#define HDR_L2_WRITING(hdr) ((hdr)->b_flags & ARC_FLAG_L2_WRITING)
#define HDR_L2_EVICTED(hdr) ((hdr)->b_flags & ARC_FLAG_L2_EVICTED)
#define HDR_L2_WRITE_HEAD(hdr) ((hdr)->b_flags & ARC_FLAG_L2_WRITE_HEAD)
+#define HDR_PROTECTED(hdr) ((hdr)->b_flags & ARC_FLAG_PROTECTED)
+#define HDR_NOAUTH(hdr) ((hdr)->b_flags & ARC_FLAG_NOAUTH)
+#define HDR_SHARED_DATA(hdr) ((hdr)->b_flags & ARC_FLAG_SHARED_DATA)
#define HDR_ISTYPE_METADATA(hdr) \
- ((hdr)->b_flags & ARC_FLAG_BUFC_METADATA)
+ ((hdr)->b_flags & ARC_FLAG_BUFC_METADATA)
#define HDR_ISTYPE_DATA(hdr) (!HDR_ISTYPE_METADATA(hdr))
#define HDR_HAS_L1HDR(hdr) ((hdr)->b_flags & ARC_FLAG_HAS_L1HDR)
#define HDR_HAS_L2HDR(hdr) ((hdr)->b_flags & ARC_FLAG_HAS_L2HDR)
+#define HDR_HAS_RABD(hdr) \
+ (HDR_HAS_L1HDR(hdr) && HDR_PROTECTED(hdr) && \
+ (hdr)->b_crypt_hdr.b_rabd != NULL)
+#define HDR_ENCRYPTED(hdr) \
+ (HDR_PROTECTED(hdr) && DMU_OT_IS_ENCRYPTED((hdr)->b_crypt_hdr.b_ot))
+#define HDR_AUTHENTICATED(hdr) \
+ (HDR_PROTECTED(hdr) && !DMU_OT_IS_ENCRYPTED((hdr)->b_crypt_hdr.b_ot))
/* For storing compression mode in b_flags */
-#define HDR_COMPRESS_OFFSET 24
-#define HDR_COMPRESS_NBITS 7
+#define HDR_COMPRESS_OFFSET (highbit64(ARC_FLAG_COMPRESS_0) - 1)
+
+#define HDR_GET_COMPRESS(hdr) ((enum zio_compress)BF32_GET((hdr)->b_flags, \
+ HDR_COMPRESS_OFFSET, SPA_COMPRESSBITS))
+#define HDR_SET_COMPRESS(hdr, cmp) BF32_SET((hdr)->b_flags, \
+ HDR_COMPRESS_OFFSET, SPA_COMPRESSBITS, (cmp));
-#define HDR_GET_COMPRESS(hdr) ((enum zio_compress)BF32_GET(hdr->b_flags, \
- HDR_COMPRESS_OFFSET, HDR_COMPRESS_NBITS))
-#define HDR_SET_COMPRESS(hdr, cmp) BF32_SET(hdr->b_flags, \
- HDR_COMPRESS_OFFSET, HDR_COMPRESS_NBITS, (cmp))
+#define ARC_BUF_LAST(buf) ((buf)->b_next == NULL)
+#define ARC_BUF_SHARED(buf) ((buf)->b_flags & ARC_BUF_FLAG_SHARED)
+#define ARC_BUF_COMPRESSED(buf) ((buf)->b_flags & ARC_BUF_FLAG_COMPRESSED)
+#define ARC_BUF_ENCRYPTED(buf) ((buf)->b_flags & ARC_BUF_FLAG_ENCRYPTED)
/*
* Other sizes
*/
-#define HDR_FULL_SIZE ((int64_t)sizeof (arc_buf_hdr_t))
+#define HDR_FULL_CRYPT_SIZE ((int64_t)sizeof (arc_buf_hdr_t))
+#define HDR_FULL_SIZE ((int64_t)offsetof(arc_buf_hdr_t, b_crypt_hdr))
#define HDR_L2ONLY_SIZE ((int64_t)offsetof(arc_buf_hdr_t, b_l1hdr))
/*
#define L2ARC_WRITE_SIZE (8 * 1024 * 1024) /* initial write max */
#define L2ARC_HEADROOM 2 /* num of writes */
+
/*
* If we discover during ARC scan any buffers to be compressed, we boost
* our headroom for the next scanning cycle by this percentage multiple.
#define L2ARC_FEED_SECS 1 /* caching interval secs */
#define L2ARC_FEED_MIN_MS 200 /* min caching interval ms */
+/*
+ * We can feed L2ARC from two states of ARC buffers, mru and mfu,
+ * and each of the state has two types: data and metadata.
+ */
+#define L2ARC_FEED_TYPES 4
+
#define l2arc_writes_sent ARCSTAT(arcstat_l2_writes_sent)
#define l2arc_writes_done ARCSTAT(arcstat_l2_writes_done)
unsigned long l2arc_feed_secs = L2ARC_FEED_SECS; /* interval seconds */
unsigned long l2arc_feed_min_ms = L2ARC_FEED_MIN_MS; /* min interval msecs */
int l2arc_noprefetch = B_TRUE; /* don't cache prefetch bufs */
-int l2arc_nocompress = B_FALSE; /* don't compress bufs */
int l2arc_feed_again = B_TRUE; /* turbo warmup */
int l2arc_norw = B_FALSE; /* no reads during writes */
static uint64_t l2arc_ndev; /* number of devices */
typedef struct l2arc_read_callback {
- arc_buf_t *l2rcb_buf; /* read buffer */
- spa_t *l2rcb_spa; /* spa */
+ arc_buf_hdr_t *l2rcb_hdr; /* read header */
blkptr_t l2rcb_bp; /* original blkptr */
zbookmark_phys_t l2rcb_zb; /* original bookmark */
int l2rcb_flags; /* original flags */
- enum zio_compress l2rcb_compress; /* applied compress */
+ abd_t *l2rcb_abd; /* temporary buffer */
} l2arc_read_callback_t;
typedef struct l2arc_data_free {
/* protected by l2arc_free_on_write_mtx */
- void *l2df_data;
+ abd_t *l2df_abd;
size_t l2df_size;
- void (*l2df_func)(void *, size_t);
+ arc_buf_contents_t l2df_type;
list_node_t l2df_list_node;
} l2arc_data_free_t;
+typedef enum arc_fill_flags {
+ ARC_FILL_LOCKED = 1 << 0, /* hdr lock is held */
+ ARC_FILL_COMPRESSED = 1 << 1, /* fill with compressed data */
+ ARC_FILL_ENCRYPTED = 1 << 2, /* fill with encrypted data */
+ ARC_FILL_NOAUTH = 1 << 3, /* don't attempt to authenticate */
+ ARC_FILL_IN_PLACE = 1 << 4 /* fill in place (special case) */
+} arc_fill_flags_t;
+
static kmutex_t l2arc_feed_thr_lock;
static kcondvar_t l2arc_feed_thr_cv;
static uint8_t l2arc_thread_exit;
-static void arc_get_data_buf(arc_buf_t *);
+static abd_t *arc_get_data_abd(arc_buf_hdr_t *, uint64_t, void *);
+static void *arc_get_data_buf(arc_buf_hdr_t *, uint64_t, void *);
+static void arc_get_data_impl(arc_buf_hdr_t *, uint64_t, void *);
+static void arc_free_data_abd(arc_buf_hdr_t *, abd_t *, uint64_t, void *);
+static void arc_free_data_buf(arc_buf_hdr_t *, void *, uint64_t, void *);
+static void arc_free_data_impl(arc_buf_hdr_t *hdr, uint64_t size, void *tag);
+static void arc_hdr_free_abd(arc_buf_hdr_t *, boolean_t);
+static void arc_hdr_alloc_abd(arc_buf_hdr_t *, boolean_t);
static void arc_access(arc_buf_hdr_t *, kmutex_t *);
static boolean_t arc_is_overflowing(void);
static void arc_buf_watch(arc_buf_t *);
+static void arc_tuning_update(void);
+static void arc_prune_async(int64_t);
+static uint64_t arc_all_memory(void);
static arc_buf_contents_t arc_buf_type(arc_buf_hdr_t *);
static uint32_t arc_bufc_to_flags(arc_buf_contents_t);
+static inline void arc_hdr_set_flags(arc_buf_hdr_t *hdr, arc_flags_t flags);
+static inline void arc_hdr_clear_flags(arc_buf_hdr_t *hdr, arc_flags_t flags);
static boolean_t l2arc_write_eligible(uint64_t, arc_buf_hdr_t *);
static void l2arc_read_done(zio_t *);
-static boolean_t l2arc_compress_buf(arc_buf_hdr_t *);
-static void l2arc_decompress_zio(zio_t *, arc_buf_hdr_t *, enum zio_compress);
-static void l2arc_release_cdata_buf(arc_buf_hdr_t *);
-
static uint64_t
buf_hash(uint64_t spa, const dva_t *dva, uint64_t birth)
{
return (crc);
}
-#define BUF_EMPTY(buf) \
- ((buf)->b_dva.dva_word[0] == 0 && \
- (buf)->b_dva.dva_word[1] == 0)
+#define HDR_EMPTY(hdr) \
+ ((hdr)->b_dva.dva_word[0] == 0 && \
+ (hdr)->b_dva.dva_word[1] == 0)
-#define BUF_EQUAL(spa, dva, birth, buf) \
- ((buf)->b_dva.dva_word[0] == (dva)->dva_word[0]) && \
- ((buf)->b_dva.dva_word[1] == (dva)->dva_word[1]) && \
- ((buf)->b_birth == birth) && ((buf)->b_spa == spa)
+#define HDR_EQUAL(spa, dva, birth, hdr) \
+ ((hdr)->b_dva.dva_word[0] == (dva)->dva_word[0]) && \
+ ((hdr)->b_dva.dva_word[1] == (dva)->dva_word[1]) && \
+ ((hdr)->b_birth == birth) && ((hdr)->b_spa == spa)
static void
buf_discard_identity(arc_buf_hdr_t *hdr)
mutex_enter(hash_lock);
for (hdr = buf_hash_table.ht_table[idx]; hdr != NULL;
hdr = hdr->b_hash_next) {
- if (BUF_EQUAL(spa, dva, birth, hdr)) {
+ if (HDR_EQUAL(spa, dva, birth, hdr)) {
*lockp = hash_lock;
return (hdr);
}
for (fhdr = buf_hash_table.ht_table[idx], i = 0; fhdr != NULL;
fhdr = fhdr->b_hash_next, i++) {
- if (BUF_EQUAL(hdr->b_spa, &hdr->b_dva, hdr->b_birth, fhdr))
+ if (HDR_EQUAL(hdr->b_spa, &hdr->b_dva, hdr->b_birth, fhdr))
return (fhdr);
}
hdr->b_hash_next = buf_hash_table.ht_table[idx];
buf_hash_table.ht_table[idx] = hdr;
- hdr->b_flags |= ARC_FLAG_IN_HASH_TABLE;
+ arc_hdr_set_flags(hdr, ARC_FLAG_IN_HASH_TABLE);
/* collect some hash table performance data */
if (i > 0) {
hdrp = &buf_hash_table.ht_table[idx];
while ((fhdr = *hdrp) != hdr) {
- ASSERT(fhdr != NULL);
+ ASSERT3P(fhdr, !=, NULL);
hdrp = &fhdr->b_hash_next;
}
*hdrp = hdr->b_hash_next;
hdr->b_hash_next = NULL;
- hdr->b_flags &= ~ARC_FLAG_IN_HASH_TABLE;
+ arc_hdr_clear_flags(hdr, ARC_FLAG_IN_HASH_TABLE);
/* collect some hash table performance data */
ARCSTAT_BUMPDOWN(arcstat_hash_elements);
/*
* Global data structures and functions for the buf kmem cache.
*/
+
static kmem_cache_t *hdr_full_cache;
+static kmem_cache_t *hdr_full_crypt_cache;
static kmem_cache_t *hdr_l2only_cache;
static kmem_cache_t *buf_cache;
for (i = 0; i < BUF_LOCKS; i++)
mutex_destroy(&buf_hash_table.ht_locks[i].ht_lock);
kmem_cache_destroy(hdr_full_cache);
+ kmem_cache_destroy(hdr_full_crypt_cache);
kmem_cache_destroy(hdr_l2only_cache);
kmem_cache_destroy(buf_cache);
}
return (0);
}
+/* ARGSUSED */
+static int
+hdr_full_crypt_cons(void *vbuf, void *unused, int kmflag)
+{
+ arc_buf_hdr_t *hdr = vbuf;
+
+ hdr_full_cons(vbuf, unused, kmflag);
+ bzero(&hdr->b_crypt_hdr, sizeof (hdr->b_crypt_hdr));
+ arc_space_consume(sizeof (hdr->b_crypt_hdr), ARC_SPACE_HDRS);
+
+ return (0);
+}
+
/* ARGSUSED */
static int
hdr_l2only_cons(void *vbuf, void *unused, int kmflag)
{
arc_buf_hdr_t *hdr = vbuf;
- ASSERT(BUF_EMPTY(hdr));
+ ASSERT(HDR_EMPTY(hdr));
cv_destroy(&hdr->b_l1hdr.b_cv);
refcount_destroy(&hdr->b_l1hdr.b_refcnt);
mutex_destroy(&hdr->b_l1hdr.b_freeze_lock);
arc_space_return(HDR_FULL_SIZE, ARC_SPACE_HDRS);
}
+/* ARGSUSED */
+static void
+hdr_full_crypt_dest(void *vbuf, void *unused)
+{
+ arc_buf_hdr_t *hdr = vbuf;
+
+ hdr_full_dest(vbuf, unused);
+ arc_space_return(sizeof (hdr->b_crypt_hdr), ARC_SPACE_HDRS);
+}
+
/* ARGSUSED */
static void
hdr_l2only_dest(void *vbuf, void *unused)
{
ASSERTV(arc_buf_hdr_t *hdr = vbuf);
- ASSERT(BUF_EMPTY(hdr));
+ ASSERT(HDR_EMPTY(hdr));
arc_space_return(HDR_L2ONLY_SIZE, ARC_SPACE_L2HDRS);
}
arc_space_return(sizeof (arc_buf_t), ARC_SPACE_HDRS);
}
+/*
+ * Reclaim callback -- invoked when memory is low.
+ */
+/* ARGSUSED */
+static void
+hdr_recl(void *unused)
+{
+ dprintf("hdr_recl called\n");
+ /*
+ * umem calls the reclaim func when we destroy the buf cache,
+ * which is after we do arc_fini().
+ */
+ if (!arc_dead)
+ cv_signal(&arc_reclaim_thread_cv);
+}
+
static void
buf_init(void)
{
- uint64_t *ct;
+ uint64_t *ct = NULL;
uint64_t hsize = 1ULL << 12;
int i, j;
* By default, the table will take up
* totalmem * sizeof(void*) / 8K (1MB per GB with 8-byte pointers).
*/
- while (hsize * zfs_arc_average_blocksize < physmem * PAGESIZE)
+ while (hsize * zfs_arc_average_blocksize < arc_all_memory())
hsize <<= 1;
retry:
buf_hash_table.ht_mask = hsize - 1;
}
hdr_full_cache = kmem_cache_create("arc_buf_hdr_t_full", HDR_FULL_SIZE,
- 0, hdr_full_cons, hdr_full_dest, NULL, NULL, NULL, 0);
+ 0, hdr_full_cons, hdr_full_dest, hdr_recl, NULL, NULL, 0);
+ hdr_full_crypt_cache = kmem_cache_create("arc_buf_hdr_t_full_crypt",
+ HDR_FULL_CRYPT_SIZE, 0, hdr_full_crypt_cons, hdr_full_crypt_dest,
+ hdr_recl, NULL, NULL, 0);
hdr_l2only_cache = kmem_cache_create("arc_buf_hdr_t_l2only",
- HDR_L2ONLY_SIZE, 0, hdr_l2only_cons, hdr_l2only_dest, NULL,
+ HDR_L2ONLY_SIZE, 0, hdr_l2only_cons, hdr_l2only_dest, hdr_recl,
NULL, NULL, 0);
buf_cache = kmem_cache_create("arc_buf_t", sizeof (arc_buf_t),
0, buf_cons, buf_dest, NULL, NULL, NULL, 0);
}
}
+#define ARC_MINTIME (hz>>4) /* 62 ms */
+
/*
- * Transition between the two allocation states for the arc_buf_hdr struct.
- * The arc_buf_hdr struct can be allocated with (hdr_full_cache) or without
- * (hdr_l2only_cache) the fields necessary for the L1 cache - the smaller
- * version is used when a cache buffer is only in the L2ARC in order to reduce
- * memory usage.
+ * This is the size that the buf occupies in memory. If the buf is compressed,
+ * it will correspond to the compressed size. You should use this method of
+ * getting the buf size unless you explicitly need the logical size.
*/
-static arc_buf_hdr_t *
-arc_hdr_realloc(arc_buf_hdr_t *hdr, kmem_cache_t *old, kmem_cache_t *new)
+uint64_t
+arc_buf_size(arc_buf_t *buf)
{
- arc_buf_hdr_t *nhdr;
- l2arc_dev_t *dev;
-
- ASSERT(HDR_HAS_L2HDR(hdr));
- ASSERT((old == hdr_full_cache && new == hdr_l2only_cache) ||
- (old == hdr_l2only_cache && new == hdr_full_cache));
+ return (ARC_BUF_COMPRESSED(buf) ?
+ HDR_GET_PSIZE(buf->b_hdr) : HDR_GET_LSIZE(buf->b_hdr));
+}
- dev = hdr->b_l2hdr.b_dev;
- nhdr = kmem_cache_alloc(new, KM_PUSHPAGE);
+uint64_t
+arc_buf_lsize(arc_buf_t *buf)
+{
+ return (HDR_GET_LSIZE(buf->b_hdr));
+}
- ASSERT(MUTEX_HELD(HDR_LOCK(hdr)));
- buf_hash_remove(hdr);
+/*
+ * This function will return B_TRUE if the buffer is encrypted in memory.
+ * This buffer can be decrypted by calling arc_untransform().
+ */
+boolean_t
+arc_is_encrypted(arc_buf_t *buf)
+{
+ return (ARC_BUF_ENCRYPTED(buf) != 0);
+}
- bcopy(hdr, nhdr, HDR_L2ONLY_SIZE);
- if (new == hdr_full_cache) {
- nhdr->b_flags |= ARC_FLAG_HAS_L1HDR;
- /*
- * arc_access and arc_change_state need to be aware that a
- * header has just come out of L2ARC, so we set its state to
- * l2c_only even though it's about to change.
- */
- nhdr->b_l1hdr.b_state = arc_l2c_only;
+/*
+ * Returns B_TRUE if the buffer represents data that has not had its MAC
+ * verified yet.
+ */
+boolean_t
+arc_is_unauthenticated(arc_buf_t *buf)
+{
+ return (HDR_NOAUTH(buf->b_hdr) != 0);
+}
- /* Verify previous threads set to NULL before freeing */
- ASSERT3P(nhdr->b_l1hdr.b_tmp_cdata, ==, NULL);
- } else {
- ASSERT(hdr->b_l1hdr.b_buf == NULL);
- ASSERT0(hdr->b_l1hdr.b_datacnt);
+void
+arc_get_raw_params(arc_buf_t *buf, boolean_t *byteorder, uint8_t *salt,
+ uint8_t *iv, uint8_t *mac)
+{
+ arc_buf_hdr_t *hdr = buf->b_hdr;
- /*
- * If we've reached here, We must have been called from
- * arc_evict_hdr(), as such we should have already been
- * removed from any ghost list we were previously on
- * (which protects us from racing with arc_evict_state),
- * thus no locking is needed during this check.
- */
- ASSERT(!multilist_link_active(&hdr->b_l1hdr.b_arc_node));
+ ASSERT(HDR_PROTECTED(hdr));
- /*
- * A buffer must not be moved into the arc_l2c_only
- * state if it's not finished being written out to the
- * l2arc device. Otherwise, the b_l1hdr.b_tmp_cdata field
- * might try to be accessed, even though it was removed.
- */
- VERIFY(!HDR_L2_WRITING(hdr));
- VERIFY3P(hdr->b_l1hdr.b_tmp_cdata, ==, NULL);
+ bcopy(hdr->b_crypt_hdr.b_salt, salt, ZIO_DATA_SALT_LEN);
+ bcopy(hdr->b_crypt_hdr.b_iv, iv, ZIO_DATA_IV_LEN);
+ bcopy(hdr->b_crypt_hdr.b_mac, mac, ZIO_DATA_MAC_LEN);
+ *byteorder = (hdr->b_l1hdr.b_byteswap == DMU_BSWAP_NUMFUNCS) ?
+ ZFS_HOST_BYTEORDER : !ZFS_HOST_BYTEORDER;
+}
- nhdr->b_flags &= ~ARC_FLAG_HAS_L1HDR;
- }
- /*
- * The header has been reallocated so we need to re-insert it into any
- * lists it was on.
- */
- (void) buf_hash_insert(nhdr, NULL);
+/*
+ * Indicates how this buffer is compressed in memory. If it is not compressed
+ * the value will be ZIO_COMPRESS_OFF. It can be made normally readable with
+ * arc_untransform() as long as it is also unencrypted.
+ */
+enum zio_compress
+arc_get_compression(arc_buf_t *buf)
+{
+ return (ARC_BUF_COMPRESSED(buf) ?
+ HDR_GET_COMPRESS(buf->b_hdr) : ZIO_COMPRESS_OFF);
+}
- ASSERT(list_link_active(&hdr->b_l2hdr.b_l2node));
+/*
+ * Return the compression algorithm used to store this data in the ARC. If ARC
+ * compression is enabled or this is an encrypted block, this will be the same
+ * as what's used to store it on-disk. Otherwise, this will be ZIO_COMPRESS_OFF.
+ */
+static inline enum zio_compress
+arc_hdr_get_compress(arc_buf_hdr_t *hdr)
+{
+ return (HDR_COMPRESSION_ENABLED(hdr) ?
+ HDR_GET_COMPRESS(hdr) : ZIO_COMPRESS_OFF);
+}
- mutex_enter(&dev->l2ad_mtx);
+static inline boolean_t
+arc_buf_is_shared(arc_buf_t *buf)
+{
+ boolean_t shared = (buf->b_data != NULL &&
+ buf->b_hdr->b_l1hdr.b_pabd != NULL &&
+ abd_is_linear(buf->b_hdr->b_l1hdr.b_pabd) &&
+ buf->b_data == abd_to_buf(buf->b_hdr->b_l1hdr.b_pabd));
+ IMPLY(shared, HDR_SHARED_DATA(buf->b_hdr));
+ IMPLY(shared, ARC_BUF_SHARED(buf));
+ IMPLY(shared, ARC_BUF_COMPRESSED(buf) || ARC_BUF_LAST(buf));
/*
- * We must place the realloc'ed header back into the list at
- * the same spot. Otherwise, if it's placed earlier in the list,
- * l2arc_write_buffers() could find it during the function's
- * write phase, and try to write it out to the l2arc.
+ * It would be nice to assert arc_can_share() too, but the "hdr isn't
+ * already being shared" requirement prevents us from doing that.
*/
- list_insert_after(&dev->l2ad_buflist, hdr, nhdr);
- list_remove(&dev->l2ad_buflist, hdr);
- mutex_exit(&dev->l2ad_mtx);
+ return (shared);
+}
- buf_discard_identity(hdr);
- hdr->b_freeze_cksum = NULL;
- kmem_cache_free(old, hdr);
+/*
+ * Free the checksum associated with this header. If there is no checksum, this
+ * is a no-op.
+ */
+static inline void
+arc_cksum_free(arc_buf_hdr_t *hdr)
+{
+ ASSERT(HDR_HAS_L1HDR(hdr));
- return (nhdr);
+ mutex_enter(&hdr->b_l1hdr.b_freeze_lock);
+ if (hdr->b_l1hdr.b_freeze_cksum != NULL) {
+ kmem_free(hdr->b_l1hdr.b_freeze_cksum, sizeof (zio_cksum_t));
+ hdr->b_l1hdr.b_freeze_cksum = NULL;
+ }
+ mutex_exit(&hdr->b_l1hdr.b_freeze_lock);
}
+/*
+ * Return true iff at least one of the bufs on hdr is not compressed.
+ * Encrypted buffers count as compressed.
+ */
+static boolean_t
+arc_hdr_has_uncompressed_buf(arc_buf_hdr_t *hdr)
+{
+ for (arc_buf_t *b = hdr->b_l1hdr.b_buf; b != NULL; b = b->b_next) {
+ if (!ARC_BUF_COMPRESSED(b)) {
+ return (B_TRUE);
+ }
+ }
+ return (B_FALSE);
+}
-#define ARC_MINTIME (hz>>4) /* 62 ms */
+/*
+ * If we've turned on the ZFS_DEBUG_MODIFY flag, verify that the buf's data
+ * matches the checksum that is stored in the hdr. If there is no checksum,
+ * or if the buf is compressed, this is a no-op.
+ */
static void
arc_cksum_verify(arc_buf_t *buf)
{
+ arc_buf_hdr_t *hdr = buf->b_hdr;
zio_cksum_t zc;
if (!(zfs_flags & ZFS_DEBUG_MODIFY))
return;
- mutex_enter(&buf->b_hdr->b_l1hdr.b_freeze_lock);
- if (buf->b_hdr->b_freeze_cksum == NULL || HDR_IO_ERROR(buf->b_hdr)) {
- mutex_exit(&buf->b_hdr->b_l1hdr.b_freeze_lock);
+ if (ARC_BUF_COMPRESSED(buf)) {
+ ASSERT(hdr->b_l1hdr.b_freeze_cksum == NULL ||
+ arc_hdr_has_uncompressed_buf(hdr));
return;
}
- fletcher_2_native(buf->b_data, buf->b_hdr->b_size, &zc);
- if (!ZIO_CHECKSUM_EQUAL(*buf->b_hdr->b_freeze_cksum, zc))
- panic("buffer modified while frozen!");
- mutex_exit(&buf->b_hdr->b_l1hdr.b_freeze_lock);
-}
-static int
-arc_cksum_equal(arc_buf_t *buf)
-{
- zio_cksum_t zc;
- int equal;
+ ASSERT(HDR_HAS_L1HDR(hdr));
- mutex_enter(&buf->b_hdr->b_l1hdr.b_freeze_lock);
- fletcher_2_native(buf->b_data, buf->b_hdr->b_size, &zc);
- equal = ZIO_CHECKSUM_EQUAL(*buf->b_hdr->b_freeze_cksum, zc);
- mutex_exit(&buf->b_hdr->b_l1hdr.b_freeze_lock);
+ mutex_enter(&hdr->b_l1hdr.b_freeze_lock);
+ if (hdr->b_l1hdr.b_freeze_cksum == NULL || HDR_IO_ERROR(hdr)) {
+ mutex_exit(&hdr->b_l1hdr.b_freeze_lock);
+ return;
+ }
- return (equal);
+ fletcher_2_native(buf->b_data, arc_buf_size(buf), NULL, &zc);
+ if (!ZIO_CHECKSUM_EQUAL(*hdr->b_l1hdr.b_freeze_cksum, zc))
+ panic("buffer modified while frozen!");
+ mutex_exit(&hdr->b_l1hdr.b_freeze_lock);
}
-static void
-arc_cksum_compute(arc_buf_t *buf, boolean_t force)
-{
- if (!force && !(zfs_flags & ZFS_DEBUG_MODIFY))
+/*
+ * This function makes the assumption that data stored in the L2ARC
+ * will be transformed exactly as it is in the main pool. Because of
+ * this we can verify the checksum against the reading process's bp.
+ */
+static boolean_t
+arc_cksum_is_equal(arc_buf_hdr_t *hdr, zio_t *zio)
+{
+ ASSERT(!BP_IS_EMBEDDED(zio->io_bp));
+ VERIFY3U(BP_GET_PSIZE(zio->io_bp), ==, HDR_GET_PSIZE(hdr));
+
+ /*
+ * Block pointers always store the checksum for the logical data.
+ * If the block pointer has the gang bit set, then the checksum
+ * it represents is for the reconstituted data and not for an
+ * individual gang member. The zio pipeline, however, must be able to
+ * determine the checksum of each of the gang constituents so it
+ * treats the checksum comparison differently than what we need
+ * for l2arc blocks. This prevents us from using the
+ * zio_checksum_error() interface directly. Instead we must call the
+ * zio_checksum_error_impl() so that we can ensure the checksum is
+ * generated using the correct checksum algorithm and accounts for the
+ * logical I/O size and not just a gang fragment.
+ */
+ return (zio_checksum_error_impl(zio->io_spa, zio->io_bp,
+ BP_GET_CHECKSUM(zio->io_bp), zio->io_abd, zio->io_size,
+ zio->io_offset, NULL) == 0);
+}
+
+/*
+ * Given a buf full of data, if ZFS_DEBUG_MODIFY is enabled this computes a
+ * checksum and attaches it to the buf's hdr so that we can ensure that the buf
+ * isn't modified later on. If buf is compressed or there is already a checksum
+ * on the hdr, this is a no-op (we only checksum uncompressed bufs).
+ */
+static void
+arc_cksum_compute(arc_buf_t *buf)
+{
+ arc_buf_hdr_t *hdr = buf->b_hdr;
+
+ if (!(zfs_flags & ZFS_DEBUG_MODIFY))
return;
+ ASSERT(HDR_HAS_L1HDR(hdr));
+
mutex_enter(&buf->b_hdr->b_l1hdr.b_freeze_lock);
- if (buf->b_hdr->b_freeze_cksum != NULL) {
- mutex_exit(&buf->b_hdr->b_l1hdr.b_freeze_lock);
+ if (hdr->b_l1hdr.b_freeze_cksum != NULL) {
+ ASSERT(arc_hdr_has_uncompressed_buf(hdr));
+ mutex_exit(&hdr->b_l1hdr.b_freeze_lock);
+ return;
+ } else if (ARC_BUF_COMPRESSED(buf)) {
+ mutex_exit(&hdr->b_l1hdr.b_freeze_lock);
return;
}
- buf->b_hdr->b_freeze_cksum = kmem_alloc(sizeof (zio_cksum_t),
+
+ ASSERT(!ARC_BUF_ENCRYPTED(buf));
+ ASSERT(!ARC_BUF_COMPRESSED(buf));
+ hdr->b_l1hdr.b_freeze_cksum = kmem_alloc(sizeof (zio_cksum_t),
KM_SLEEP);
- fletcher_2_native(buf->b_data, buf->b_hdr->b_size,
- buf->b_hdr->b_freeze_cksum);
- mutex_exit(&buf->b_hdr->b_l1hdr.b_freeze_lock);
+ fletcher_2_native(buf->b_data, arc_buf_size(buf), NULL,
+ hdr->b_l1hdr.b_freeze_cksum);
+ mutex_exit(&hdr->b_l1hdr.b_freeze_lock);
arc_buf_watch(buf);
}
void
arc_buf_sigsegv(int sig, siginfo_t *si, void *unused)
{
- panic("Got SIGSEGV at address: 0x%lx\n", (long) si->si_addr);
+ panic("Got SIGSEGV at address: 0x%lx\n", (long)si->si_addr);
}
#endif
{
#ifndef _KERNEL
if (arc_watch) {
- ASSERT0(mprotect(buf->b_data, buf->b_hdr->b_size,
+ ASSERT0(mprotect(buf->b_data, arc_buf_size(buf),
PROT_READ | PROT_WRITE));
}
#endif
{
#ifndef _KERNEL
if (arc_watch)
- ASSERT0(mprotect(buf->b_data, buf->b_hdr->b_size, PROT_READ));
+ ASSERT0(mprotect(buf->b_data, arc_buf_size(buf),
+ PROT_READ));
#endif
}
static arc_buf_contents_t
arc_buf_type(arc_buf_hdr_t *hdr)
{
+ arc_buf_contents_t type;
if (HDR_ISTYPE_METADATA(hdr)) {
- return (ARC_BUFC_METADATA);
+ type = ARC_BUFC_METADATA;
} else {
- return (ARC_BUFC_DATA);
+ type = ARC_BUFC_DATA;
}
+ VERIFY3U(hdr->b_type, ==, type);
+ return (type);
+}
+
+boolean_t
+arc_is_metadata(arc_buf_t *buf)
+{
+ return (HDR_ISTYPE_METADATA(buf->b_hdr) != 0);
}
static uint32_t
void
arc_buf_thaw(arc_buf_t *buf)
{
- if (zfs_flags & ZFS_DEBUG_MODIFY) {
- if (buf->b_hdr->b_l1hdr.b_state != arc_anon)
- panic("modifying non-anon buffer!");
- if (HDR_IO_IN_PROGRESS(buf->b_hdr))
- panic("modifying buffer while i/o in progress!");
- arc_cksum_verify(buf);
- }
+ arc_buf_hdr_t *hdr = buf->b_hdr;
- mutex_enter(&buf->b_hdr->b_l1hdr.b_freeze_lock);
- if (buf->b_hdr->b_freeze_cksum != NULL) {
- kmem_free(buf->b_hdr->b_freeze_cksum, sizeof (zio_cksum_t));
- buf->b_hdr->b_freeze_cksum = NULL;
- }
+ ASSERT3P(hdr->b_l1hdr.b_state, ==, arc_anon);
+ ASSERT(!HDR_IO_IN_PROGRESS(hdr));
- mutex_exit(&buf->b_hdr->b_l1hdr.b_freeze_lock);
+ arc_cksum_verify(buf);
+
+ /*
+ * Compressed buffers do not manipulate the b_freeze_cksum or
+ * allocate b_thawed.
+ */
+ if (ARC_BUF_COMPRESSED(buf)) {
+ ASSERT(hdr->b_l1hdr.b_freeze_cksum == NULL ||
+ arc_hdr_has_uncompressed_buf(hdr));
+ return;
+ }
+ ASSERT(HDR_HAS_L1HDR(hdr));
+ arc_cksum_free(hdr);
arc_buf_unwatch(buf);
}
void
arc_buf_freeze(arc_buf_t *buf)
{
+ arc_buf_hdr_t *hdr = buf->b_hdr;
kmutex_t *hash_lock;
if (!(zfs_flags & ZFS_DEBUG_MODIFY))
return;
- hash_lock = HDR_LOCK(buf->b_hdr);
+ if (ARC_BUF_COMPRESSED(buf)) {
+ ASSERT(hdr->b_l1hdr.b_freeze_cksum == NULL ||
+ arc_hdr_has_uncompressed_buf(hdr));
+ return;
+ }
+
+ hash_lock = HDR_LOCK(hdr);
mutex_enter(hash_lock);
- ASSERT(buf->b_hdr->b_freeze_cksum != NULL ||
- buf->b_hdr->b_l1hdr.b_state == arc_anon);
- arc_cksum_compute(buf, B_FALSE);
+ ASSERT(HDR_HAS_L1HDR(hdr));
+ ASSERT(hdr->b_l1hdr.b_freeze_cksum != NULL ||
+ hdr->b_l1hdr.b_state == arc_anon);
+ arc_cksum_compute(buf);
mutex_exit(hash_lock);
-
}
-static void
-add_reference(arc_buf_hdr_t *hdr, kmutex_t *hash_lock, void *tag)
+/*
+ * The arc_buf_hdr_t's b_flags should never be modified directly. Instead,
+ * the following functions should be used to ensure that the flags are
+ * updated in a thread-safe way. When manipulating the flags either
+ * the hash_lock must be held or the hdr must be undiscoverable. This
+ * ensures that we're not racing with any other threads when updating
+ * the flags.
+ */
+static inline void
+arc_hdr_set_flags(arc_buf_hdr_t *hdr, arc_flags_t flags)
{
- arc_state_t *state;
-
- ASSERT(HDR_HAS_L1HDR(hdr));
- ASSERT(MUTEX_HELD(hash_lock));
-
- state = hdr->b_l1hdr.b_state;
+ ASSERT(MUTEX_HELD(HDR_LOCK(hdr)) || HDR_EMPTY(hdr));
+ hdr->b_flags |= flags;
+}
- if ((refcount_add(&hdr->b_l1hdr.b_refcnt, tag) == 1) &&
- (state != arc_anon)) {
- /* We don't use the L2-only state list. */
- if (state != arc_l2c_only) {
- arc_buf_contents_t type = arc_buf_type(hdr);
- uint64_t delta = hdr->b_size * hdr->b_l1hdr.b_datacnt;
- multilist_t *list = &state->arcs_list[type];
- uint64_t *size = &state->arcs_lsize[type];
+static inline void
+arc_hdr_clear_flags(arc_buf_hdr_t *hdr, arc_flags_t flags)
+{
+ ASSERT(MUTEX_HELD(HDR_LOCK(hdr)) || HDR_EMPTY(hdr));
+ hdr->b_flags &= ~flags;
+}
- multilist_remove(list, hdr);
+/*
+ * Setting the compression bits in the arc_buf_hdr_t's b_flags is
+ * done in a special way since we have to clear and set bits
+ * at the same time. Consumers that wish to set the compression bits
+ * must use this function to ensure that the flags are updated in
+ * thread-safe manner.
+ */
+static void
+arc_hdr_set_compress(arc_buf_hdr_t *hdr, enum zio_compress cmp)
+{
+ ASSERT(MUTEX_HELD(HDR_LOCK(hdr)) || HDR_EMPTY(hdr));
- if (GHOST_STATE(state)) {
- ASSERT0(hdr->b_l1hdr.b_datacnt);
- ASSERT3P(hdr->b_l1hdr.b_buf, ==, NULL);
- delta = hdr->b_size;
- }
- ASSERT(delta > 0);
- ASSERT3U(*size, >=, delta);
- atomic_add_64(size, -delta);
- }
- /* remove the prefetch flag if we get a reference */
- hdr->b_flags &= ~ARC_FLAG_PREFETCH;
+ /*
+ * Holes and embedded blocks will always have a psize = 0 so
+ * we ignore the compression of the blkptr and set the
+ * want to uncompress them. Mark them as uncompressed.
+ */
+ if (!zfs_compressed_arc_enabled || HDR_GET_PSIZE(hdr) == 0) {
+ arc_hdr_clear_flags(hdr, ARC_FLAG_COMPRESSED_ARC);
+ ASSERT(!HDR_COMPRESSION_ENABLED(hdr));
+ } else {
+ arc_hdr_set_flags(hdr, ARC_FLAG_COMPRESSED_ARC);
+ ASSERT(HDR_COMPRESSION_ENABLED(hdr));
}
+
+ HDR_SET_COMPRESS(hdr, cmp);
+ ASSERT3U(HDR_GET_COMPRESS(hdr), ==, cmp);
}
-static int
-remove_reference(arc_buf_hdr_t *hdr, kmutex_t *hash_lock, void *tag)
+/*
+ * Looks for another buf on the same hdr which has the data decompressed, copies
+ * from it, and returns true. If no such buf exists, returns false.
+ */
+static boolean_t
+arc_buf_try_copy_decompressed_data(arc_buf_t *buf)
{
- int cnt;
- arc_state_t *state = hdr->b_l1hdr.b_state;
+ arc_buf_hdr_t *hdr = buf->b_hdr;
+ boolean_t copied = B_FALSE;
ASSERT(HDR_HAS_L1HDR(hdr));
- ASSERT(state == arc_anon || MUTEX_HELD(hash_lock));
- ASSERT(!GHOST_STATE(state));
+ ASSERT3P(buf->b_data, !=, NULL);
+ ASSERT(!ARC_BUF_COMPRESSED(buf));
+
+ for (arc_buf_t *from = hdr->b_l1hdr.b_buf; from != NULL;
+ from = from->b_next) {
+ /* can't use our own data buffer */
+ if (from == buf) {
+ continue;
+ }
+
+ if (!ARC_BUF_COMPRESSED(from)) {
+ bcopy(from->b_data, buf->b_data, arc_buf_size(buf));
+ copied = B_TRUE;
+ break;
+ }
+ }
/*
- * arc_l2c_only counts as a ghost state so we don't need to explicitly
- * check to prevent usage of the arc_l2c_only list.
+ * There were no decompressed bufs, so there should not be a
+ * checksum on the hdr either.
*/
- if (((cnt = refcount_remove(&hdr->b_l1hdr.b_refcnt, tag)) == 0) &&
- (state != arc_anon)) {
- arc_buf_contents_t type = arc_buf_type(hdr);
- multilist_t *list = &state->arcs_list[type];
- uint64_t *size = &state->arcs_lsize[type];
+ EQUIV(!copied, hdr->b_l1hdr.b_freeze_cksum == NULL);
- multilist_insert(list, hdr);
-
- ASSERT(hdr->b_l1hdr.b_datacnt > 0);
- atomic_add_64(size, hdr->b_size *
- hdr->b_l1hdr.b_datacnt);
- }
- return (cnt);
+ return (copied);
}
/*
- * Returns detailed information about a specific arc buffer. When the
- * state_index argument is set the function will calculate the arc header
- * list position for its arc state. Since this requires a linear traversal
- * callers are strongly encourage not to do this. However, it can be helpful
- * for targeted analysis so the functionality is provided.
+ * Return the size of the block, b_pabd, that is stored in the arc_buf_hdr_t.
*/
-void
-arc_buf_info(arc_buf_t *ab, arc_buf_info_t *abi, int state_index)
+static uint64_t
+arc_hdr_size(arc_buf_hdr_t *hdr)
{
- arc_buf_hdr_t *hdr = ab->b_hdr;
- l1arc_buf_hdr_t *l1hdr = NULL;
- l2arc_buf_hdr_t *l2hdr = NULL;
- arc_state_t *state = NULL;
+ uint64_t size;
- if (HDR_HAS_L1HDR(hdr)) {
- l1hdr = &hdr->b_l1hdr;
- state = l1hdr->b_state;
+ if (arc_hdr_get_compress(hdr) != ZIO_COMPRESS_OFF &&
+ HDR_GET_PSIZE(hdr) > 0) {
+ size = HDR_GET_PSIZE(hdr);
+ } else {
+ ASSERT3U(HDR_GET_LSIZE(hdr), !=, 0);
+ size = HDR_GET_LSIZE(hdr);
}
- if (HDR_HAS_L2HDR(hdr))
- l2hdr = &hdr->b_l2hdr;
+ return (size);
+}
- memset(abi, 0, sizeof (arc_buf_info_t));
- abi->abi_flags = hdr->b_flags;
+static int
+arc_hdr_authenticate(arc_buf_hdr_t *hdr, spa_t *spa, uint64_t dsobj)
+{
+ int ret;
+ uint64_t csize;
+ uint64_t lsize = HDR_GET_LSIZE(hdr);
+ uint64_t psize = HDR_GET_PSIZE(hdr);
+ void *tmpbuf = NULL;
+ abd_t *abd = hdr->b_l1hdr.b_pabd;
- if (l1hdr) {
- abi->abi_datacnt = l1hdr->b_datacnt;
- abi->abi_access = l1hdr->b_arc_access;
- abi->abi_mru_hits = l1hdr->b_mru_hits;
- abi->abi_mru_ghost_hits = l1hdr->b_mru_ghost_hits;
- abi->abi_mfu_hits = l1hdr->b_mfu_hits;
- abi->abi_mfu_ghost_hits = l1hdr->b_mfu_ghost_hits;
- abi->abi_holds = refcount_count(&l1hdr->b_refcnt);
+ ASSERT(HDR_LOCK(hdr) == NULL || MUTEX_HELD(HDR_LOCK(hdr)));
+ ASSERT(HDR_AUTHENTICATED(hdr));
+ ASSERT3P(hdr->b_l1hdr.b_pabd, !=, NULL);
+
+ /*
+ * The MAC is calculated on the compressed data that is stored on disk.
+ * However, if compressed arc is disabled we will only have the
+ * decompressed data available to us now. Compress it into a temporary
+ * abd so we can verify the MAC. The performance overhead of this will
+ * be relatively low, since most objects in an encrypted objset will
+ * be encrypted (instead of authenticated) anyway.
+ */
+ if (HDR_GET_COMPRESS(hdr) != ZIO_COMPRESS_OFF &&
+ !HDR_COMPRESSION_ENABLED(hdr)) {
+ tmpbuf = zio_buf_alloc(lsize);
+ abd = abd_get_from_buf(tmpbuf, lsize);
+ abd_take_ownership_of_buf(abd, B_TRUE);
+
+ csize = zio_compress_data(HDR_GET_COMPRESS(hdr),
+ hdr->b_l1hdr.b_pabd, tmpbuf, lsize);
+ ASSERT3U(csize, <=, psize);
+ abd_zero_off(abd, csize, psize - csize);
}
- if (l2hdr) {
- abi->abi_l2arc_dattr = l2hdr->b_daddr;
- abi->abi_l2arc_asize = l2hdr->b_asize;
- abi->abi_l2arc_compress = HDR_GET_COMPRESS(hdr);
- abi->abi_l2arc_hits = l2hdr->b_hits;
+ /*
+ * Authentication is best effort. We authenticate whenever the key is
+ * available. If we succeed we clear ARC_FLAG_NOAUTH.
+ */
+ if (hdr->b_crypt_hdr.b_ot == DMU_OT_OBJSET) {
+ ASSERT3U(HDR_GET_COMPRESS(hdr), ==, ZIO_COMPRESS_OFF);
+ ASSERT3U(lsize, ==, psize);
+ ret = spa_do_crypt_objset_mac_abd(B_FALSE, spa, dsobj, abd,
+ psize, hdr->b_l1hdr.b_byteswap != DMU_BSWAP_NUMFUNCS);
+ } else {
+ ret = spa_do_crypt_mac_abd(B_FALSE, spa, dsobj, abd, psize,
+ hdr->b_crypt_hdr.b_mac);
}
- abi->abi_state_type = state ? state->arcs_state : ARC_STATE_ANON;
- abi->abi_state_contents = arc_buf_type(hdr);
- abi->abi_size = hdr->b_size;
+ if (ret == 0)
+ arc_hdr_clear_flags(hdr, ARC_FLAG_NOAUTH);
+ else if (ret != ENOENT)
+ goto error;
+
+ if (tmpbuf != NULL)
+ abd_free(abd);
+
+ return (0);
+
+error:
+ if (tmpbuf != NULL)
+ abd_free(abd);
+
+ return (ret);
}
/*
- * Move the supplied buffer to the indicated state. The hash lock
- * for the buffer must be held by the caller.
+ * This function will take a header that only has raw encrypted data in
+ * b_crypt_hdr.b_rabd and decrypt it into a new buffer which is stored in
+ * b_l1hdr.b_pabd. If designated in the header flags, this function will
+ * also decompress the data.
*/
-static void
-arc_change_state(arc_state_t *new_state, arc_buf_hdr_t *hdr,
- kmutex_t *hash_lock)
+static int
+arc_hdr_decrypt(arc_buf_hdr_t *hdr, spa_t *spa, uint64_t dsobj)
{
- arc_state_t *old_state;
- int64_t refcnt;
- uint32_t datacnt;
- uint64_t from_delta, to_delta;
- arc_buf_contents_t buftype = arc_buf_type(hdr);
+ int ret;
+ dsl_crypto_key_t *dck = NULL;
+ abd_t *cabd = NULL;
+ void *tmp = NULL;
+ boolean_t no_crypt = B_FALSE;
+ boolean_t bswap = (hdr->b_l1hdr.b_byteswap != DMU_BSWAP_NUMFUNCS);
+
+ ASSERT(HDR_LOCK(hdr) == NULL || MUTEX_HELD(HDR_LOCK(hdr)));
+ ASSERT(HDR_ENCRYPTED(hdr));
+
+ arc_hdr_alloc_abd(hdr, B_FALSE);
/*
- * We almost always have an L1 hdr here, since we call arc_hdr_realloc()
- * in arc_read() when bringing a buffer out of the L2ARC. However, the
- * L1 hdr doesn't always exist when we change state to arc_anon before
- * destroying a header, in which case reallocating to add the L1 hdr is
- * pointless.
+ * We must be careful to use the passed-in dsobj value here and
+ * not the value in b_dsobj. b_dsobj is meant to be a best guess for
+ * the L2ARC, which has the luxury of being able to fail without real
+ * consequences (the data simply won't make it to the L2ARC). In
+ * reality, the dsobj stored in the header may belong to a dataset
+ * that has been unmounted or otherwise disowned, meaning the key
+ * won't be accessible via that dsobj anymore.
*/
- if (HDR_HAS_L1HDR(hdr)) {
- old_state = hdr->b_l1hdr.b_state;
- refcnt = refcount_count(&hdr->b_l1hdr.b_refcnt);
- datacnt = hdr->b_l1hdr.b_datacnt;
- } else {
- old_state = arc_l2c_only;
- refcnt = 0;
- datacnt = 0;
+ ret = spa_keystore_lookup_key(spa, dsobj, FTAG, &dck);
+ if (ret != 0) {
+ ret = SET_ERROR(EACCES);
+ goto error;
}
- ASSERT(MUTEX_HELD(hash_lock));
- ASSERT3P(new_state, !=, old_state);
- ASSERT(refcnt == 0 || datacnt > 0);
- ASSERT(!GHOST_STATE(new_state) || datacnt == 0);
- ASSERT(old_state != arc_anon || datacnt <= 1);
+ ret = zio_do_crypt_abd(B_FALSE, &dck->dck_key,
+ hdr->b_crypt_hdr.b_salt, hdr->b_crypt_hdr.b_ot,
+ hdr->b_crypt_hdr.b_iv, hdr->b_crypt_hdr.b_mac,
+ HDR_GET_PSIZE(hdr), bswap, hdr->b_l1hdr.b_pabd,
+ hdr->b_crypt_hdr.b_rabd, &no_crypt);
+ if (ret != 0)
+ goto error;
- from_delta = to_delta = datacnt * hdr->b_size;
+ if (no_crypt) {
+ abd_copy(hdr->b_l1hdr.b_pabd, hdr->b_crypt_hdr.b_rabd,
+ HDR_GET_PSIZE(hdr));
+ }
/*
- * If this buffer is evictable, transfer it from the
- * old state list to the new state list.
+ * If this header has disabled arc compression but the b_pabd is
+ * compressed after decrypting it, we need to decompress the newly
+ * decrypted data.
*/
- if (refcnt == 0) {
- if (old_state != arc_anon && old_state != arc_l2c_only) {
- uint64_t *size = &old_state->arcs_lsize[buftype];
-
- ASSERT(HDR_HAS_L1HDR(hdr));
- multilist_remove(&old_state->arcs_list[buftype], hdr);
-
- /*
- * If prefetching out of the ghost cache,
- * we will have a non-zero datacnt.
- */
- if (GHOST_STATE(old_state) && datacnt == 0) {
- /* ghost elements have a ghost size */
- ASSERT(hdr->b_l1hdr.b_buf == NULL);
- from_delta = hdr->b_size;
- }
- ASSERT3U(*size, >=, from_delta);
- atomic_add_64(size, -from_delta);
+ if (HDR_GET_COMPRESS(hdr) != ZIO_COMPRESS_OFF &&
+ !HDR_COMPRESSION_ENABLED(hdr)) {
+ /*
+ * We want to make sure that we are correctly honoring the
+ * zfs_abd_scatter_enabled setting, so we allocate an abd here
+ * and then loan a buffer from it, rather than allocating a
+ * linear buffer and wrapping it in an abd later.
+ */
+ cabd = arc_get_data_abd(hdr, arc_hdr_size(hdr), hdr);
+ tmp = abd_borrow_buf(cabd, arc_hdr_size(hdr));
+
+ ret = zio_decompress_data(HDR_GET_COMPRESS(hdr),
+ hdr->b_l1hdr.b_pabd, tmp, HDR_GET_PSIZE(hdr),
+ HDR_GET_LSIZE(hdr));
+ if (ret != 0) {
+ abd_return_buf(cabd, tmp, arc_hdr_size(hdr));
+ goto error;
}
- if (new_state != arc_anon && new_state != arc_l2c_only) {
- uint64_t *size = &new_state->arcs_lsize[buftype];
-
- /*
- * An L1 header always exists here, since if we're
- * moving to some L1-cached state (i.e. not l2c_only or
- * anonymous), we realloc the header to add an L1hdr
- * beforehand.
- */
- ASSERT(HDR_HAS_L1HDR(hdr));
- multilist_insert(&new_state->arcs_list[buftype], hdr);
- /* ghost elements have a ghost size */
- if (GHOST_STATE(new_state)) {
- ASSERT0(datacnt);
- ASSERT(hdr->b_l1hdr.b_buf == NULL);
- to_delta = hdr->b_size;
- }
- atomic_add_64(size, to_delta);
- }
+ abd_return_buf_copy(cabd, tmp, arc_hdr_size(hdr));
+ arc_free_data_abd(hdr, hdr->b_l1hdr.b_pabd,
+ arc_hdr_size(hdr), hdr);
+ hdr->b_l1hdr.b_pabd = cabd;
}
- ASSERT(!BUF_EMPTY(hdr));
- if (new_state == arc_anon && HDR_IN_HASH_TABLE(hdr))
- buf_hash_remove(hdr);
+ spa_keystore_dsl_key_rele(spa, dck, FTAG);
- /* adjust state sizes (ignore arc_l2c_only) */
- if (to_delta && new_state != arc_l2c_only)
- atomic_add_64(&new_state->arcs_size, to_delta);
- if (from_delta && old_state != arc_l2c_only) {
- ASSERT3U(old_state->arcs_size, >=, from_delta);
- atomic_add_64(&old_state->arcs_size, -from_delta);
- }
- if (HDR_HAS_L1HDR(hdr))
- hdr->b_l1hdr.b_state = new_state;
+ return (0);
- /*
- * L2 headers should never be on the L2 state list since they don't
- * have L1 headers allocated.
- */
- ASSERT(multilist_is_empty(&arc_l2c_only->arcs_list[ARC_BUFC_DATA]) &&
- multilist_is_empty(&arc_l2c_only->arcs_list[ARC_BUFC_METADATA]));
+error:
+ arc_hdr_free_abd(hdr, B_FALSE);
+ if (dck != NULL)
+ spa_keystore_dsl_key_rele(spa, dck, FTAG);
+ if (cabd != NULL)
+ arc_free_data_buf(hdr, cabd, arc_hdr_size(hdr), hdr);
+
+ return (ret);
}
-void
-arc_space_consume(uint64_t space, arc_space_type_t type)
+/*
+ * This function is called during arc_buf_fill() to prepare the header's
+ * abd plaintext pointer for use. This involves authenticated protected
+ * data and decrypting encrypted data into the plaintext abd.
+ */
+static int
+arc_fill_hdr_crypt(arc_buf_hdr_t *hdr, kmutex_t *hash_lock, spa_t *spa,
+ uint64_t dsobj, boolean_t noauth)
{
- ASSERT(type >= 0 && type < ARC_SPACE_NUMTYPES);
+ int ret;
- switch (type) {
- default:
- break;
- case ARC_SPACE_DATA:
- ARCSTAT_INCR(arcstat_data_size, space);
- break;
- case ARC_SPACE_META:
- ARCSTAT_INCR(arcstat_meta_size, space);
- break;
- case ARC_SPACE_OTHER:
- ARCSTAT_INCR(arcstat_other_size, space);
- break;
- case ARC_SPACE_HDRS:
- ARCSTAT_INCR(arcstat_hdr_size, space);
- break;
- case ARC_SPACE_L2HDRS:
- ARCSTAT_INCR(arcstat_l2_hdr_size, space);
- break;
- }
+ ASSERT(HDR_PROTECTED(hdr));
- if (type != ARC_SPACE_DATA) {
- ARCSTAT_INCR(arcstat_meta_used, space);
- if (arc_meta_max < arc_meta_used)
- arc_meta_max = arc_meta_used;
+ if (hash_lock != NULL)
+ mutex_enter(hash_lock);
+
+ if (HDR_NOAUTH(hdr) && !noauth) {
+ /*
+ * The caller requested authenticated data but our data has
+ * not been authenticated yet. Verify the MAC now if we can.
+ */
+ ret = arc_hdr_authenticate(hdr, spa, dsobj);
+ if (ret != 0)
+ goto error;
+ } else if (HDR_HAS_RABD(hdr) && hdr->b_l1hdr.b_pabd == NULL) {
+ /*
+ * If we only have the encrypted version of the data, but the
+ * unencrypted version was requested we take this opportunity
+ * to store the decrypted version in the header for future use.
+ */
+ ret = arc_hdr_decrypt(hdr, spa, dsobj);
+ if (ret != 0)
+ goto error;
}
- atomic_add_64(&arc_size, space);
-}
+ ASSERT3P(hdr->b_l1hdr.b_pabd, !=, NULL);
-void
-arc_space_return(uint64_t space, arc_space_type_t type)
-{
- ASSERT(type >= 0 && type < ARC_SPACE_NUMTYPES);
+ if (hash_lock != NULL)
+ mutex_exit(hash_lock);
- switch (type) {
- default:
- break;
+ return (0);
+
+error:
+ if (hash_lock != NULL)
+ mutex_exit(hash_lock);
+
+ return (ret);
+}
+
+/*
+ * This function is used by the dbuf code to decrypt bonus buffers in place.
+ * The dbuf code itself doesn't have any locking for decrypting a shared dnode
+ * block, so we use the hash lock here to protect against concurrent calls to
+ * arc_buf_fill().
+ */
+static void
+arc_buf_untransform_in_place(arc_buf_t *buf, kmutex_t *hash_lock)
+{
+ arc_buf_hdr_t *hdr = buf->b_hdr;
+
+ ASSERT(HDR_ENCRYPTED(hdr));
+ ASSERT3U(hdr->b_crypt_hdr.b_ot, ==, DMU_OT_DNODE);
+ ASSERT(HDR_LOCK(hdr) == NULL || MUTEX_HELD(HDR_LOCK(hdr)));
+ ASSERT3P(hdr->b_l1hdr.b_pabd, !=, NULL);
+
+ zio_crypt_copy_dnode_bonus(hdr->b_l1hdr.b_pabd, buf->b_data,
+ arc_buf_size(buf));
+ buf->b_flags &= ~ARC_BUF_FLAG_ENCRYPTED;
+ buf->b_flags &= ~ARC_BUF_FLAG_COMPRESSED;
+ hdr->b_crypt_hdr.b_ebufcnt -= 1;
+}
+
+/*
+ * Given a buf that has a data buffer attached to it, this function will
+ * efficiently fill the buf with data of the specified compression setting from
+ * the hdr and update the hdr's b_freeze_cksum if necessary. If the buf and hdr
+ * are already sharing a data buf, no copy is performed.
+ *
+ * If the buf is marked as compressed but uncompressed data was requested, this
+ * will allocate a new data buffer for the buf, remove that flag, and fill the
+ * buf with uncompressed data. You can't request a compressed buf on a hdr with
+ * uncompressed data, and (since we haven't added support for it yet) if you
+ * want compressed data your buf must already be marked as compressed and have
+ * the correct-sized data buffer.
+ */
+static int
+arc_buf_fill(arc_buf_t *buf, spa_t *spa, uint64_t dsobj, arc_fill_flags_t flags)
+{
+ int error = 0;
+ arc_buf_hdr_t *hdr = buf->b_hdr;
+ boolean_t hdr_compressed =
+ (arc_hdr_get_compress(hdr) != ZIO_COMPRESS_OFF);
+ boolean_t compressed = (flags & ARC_FILL_COMPRESSED) != 0;
+ boolean_t encrypted = (flags & ARC_FILL_ENCRYPTED) != 0;
+ dmu_object_byteswap_t bswap = hdr->b_l1hdr.b_byteswap;
+ kmutex_t *hash_lock = (flags & ARC_FILL_LOCKED) ? NULL : HDR_LOCK(hdr);
+
+ ASSERT3P(buf->b_data, !=, NULL);
+ IMPLY(compressed, hdr_compressed || ARC_BUF_ENCRYPTED(buf));
+ IMPLY(compressed, ARC_BUF_COMPRESSED(buf));
+ IMPLY(encrypted, HDR_ENCRYPTED(hdr));
+ IMPLY(encrypted, ARC_BUF_ENCRYPTED(buf));
+ IMPLY(encrypted, ARC_BUF_COMPRESSED(buf));
+ IMPLY(encrypted, !ARC_BUF_SHARED(buf));
+
+ /*
+ * If the caller wanted encrypted data we just need to copy it from
+ * b_rabd and potentially byteswap it. We won't be able to do any
+ * further transforms on it.
+ */
+ if (encrypted) {
+ ASSERT(HDR_HAS_RABD(hdr));
+ abd_copy_to_buf(buf->b_data, hdr->b_crypt_hdr.b_rabd,
+ HDR_GET_PSIZE(hdr));
+ goto byteswap;
+ }
+
+ /*
+ * Adjust encrypted and authenticated headers to accomodate the
+ * request if needed.
+ */
+ if (HDR_PROTECTED(hdr)) {
+ error = arc_fill_hdr_crypt(hdr, hash_lock, spa,
+ dsobj, !!(flags & ARC_FILL_NOAUTH));
+ if (error != 0)
+ return (error);
+ }
+
+ /*
+ * There is a special case here for dnode blocks which are
+ * decrypting their bonus buffers. These blocks may request to
+ * be decrypted in-place. This is necessary because there may
+ * be many dnodes pointing into this buffer and there is
+ * currently no method to synchronize replacing the backing
+ * b_data buffer and updating all of the pointers. Here we use
+ * the hash lock to ensure there are no races. If the need
+ * arises for other types to be decrypted in-place, they must
+ * add handling here as well.
+ */
+ if ((flags & ARC_FILL_IN_PLACE) != 0) {
+ ASSERT(!hdr_compressed);
+ ASSERT(!compressed);
+ ASSERT(!encrypted);
+
+ if (HDR_ENCRYPTED(hdr) && ARC_BUF_ENCRYPTED(buf)) {
+ ASSERT3U(hdr->b_crypt_hdr.b_ot, ==, DMU_OT_DNODE);
+
+ if (hash_lock != NULL)
+ mutex_enter(hash_lock);
+ arc_buf_untransform_in_place(buf, hash_lock);
+ if (hash_lock != NULL)
+ mutex_exit(hash_lock);
+
+ /* Compute the hdr's checksum if necessary */
+ arc_cksum_compute(buf);
+ }
+
+ return (0);
+ }
+
+ if (hdr_compressed == compressed) {
+ if (!arc_buf_is_shared(buf)) {
+ abd_copy_to_buf(buf->b_data, hdr->b_l1hdr.b_pabd,
+ arc_buf_size(buf));
+ }
+ } else {
+ ASSERT(hdr_compressed);
+ ASSERT(!compressed);
+ ASSERT3U(HDR_GET_LSIZE(hdr), !=, HDR_GET_PSIZE(hdr));
+
+ /*
+ * If the buf is sharing its data with the hdr, unlink it and
+ * allocate a new data buffer for the buf.
+ */
+ if (arc_buf_is_shared(buf)) {
+ ASSERT(ARC_BUF_COMPRESSED(buf));
+
+ /* We need to give the buf it's own b_data */
+ buf->b_flags &= ~ARC_BUF_FLAG_SHARED;
+ buf->b_data =
+ arc_get_data_buf(hdr, HDR_GET_LSIZE(hdr), buf);
+ arc_hdr_clear_flags(hdr, ARC_FLAG_SHARED_DATA);
+
+ /* Previously overhead was 0; just add new overhead */
+ ARCSTAT_INCR(arcstat_overhead_size, HDR_GET_LSIZE(hdr));
+ } else if (ARC_BUF_COMPRESSED(buf)) {
+ /* We need to reallocate the buf's b_data */
+ arc_free_data_buf(hdr, buf->b_data, HDR_GET_PSIZE(hdr),
+ buf);
+ buf->b_data =
+ arc_get_data_buf(hdr, HDR_GET_LSIZE(hdr), buf);
+
+ /* We increased the size of b_data; update overhead */
+ ARCSTAT_INCR(arcstat_overhead_size,
+ HDR_GET_LSIZE(hdr) - HDR_GET_PSIZE(hdr));
+ }
+
+ /*
+ * Regardless of the buf's previous compression settings, it
+ * should not be compressed at the end of this function.
+ */
+ buf->b_flags &= ~ARC_BUF_FLAG_COMPRESSED;
+
+ /*
+ * Try copying the data from another buf which already has a
+ * decompressed version. If that's not possible, it's time to
+ * bite the bullet and decompress the data from the hdr.
+ */
+ if (arc_buf_try_copy_decompressed_data(buf)) {
+ /* Skip byteswapping and checksumming (already done) */
+ ASSERT3P(hdr->b_l1hdr.b_freeze_cksum, !=, NULL);
+ return (0);
+ } else {
+ error = zio_decompress_data(HDR_GET_COMPRESS(hdr),
+ hdr->b_l1hdr.b_pabd, buf->b_data,
+ HDR_GET_PSIZE(hdr), HDR_GET_LSIZE(hdr));
+
+ /*
+ * Absent hardware errors or software bugs, this should
+ * be impossible, but log it anyway so we can debug it.
+ */
+ if (error != 0) {
+ zfs_dbgmsg(
+ "hdr %p, compress %d, psize %d, lsize %d",
+ hdr, arc_hdr_get_compress(hdr),
+ HDR_GET_PSIZE(hdr), HDR_GET_LSIZE(hdr));
+ return (SET_ERROR(EIO));
+ }
+ }
+ }
+
+byteswap:
+ /* Byteswap the buf's data if necessary */
+ if (bswap != DMU_BSWAP_NUMFUNCS) {
+ ASSERT(!HDR_SHARED_DATA(hdr));
+ ASSERT3U(bswap, <, DMU_BSWAP_NUMFUNCS);
+ dmu_ot_byteswap[bswap].ob_func(buf->b_data, HDR_GET_LSIZE(hdr));
+ }
+
+ /* Compute the hdr's checksum if necessary */
+ arc_cksum_compute(buf);
+
+ return (0);
+}
+
+/*
+ * If this function is being called to decrypt an encrypted buffer or verify an
+ * authenticated one, the key must be loaded and a mapping must be made
+ * available in the keystore via spa_keystore_create_mapping() or one of its
+ * callers.
+ */
+int
+arc_untransform(arc_buf_t *buf, spa_t *spa, uint64_t dsobj, boolean_t in_place)
+{
+ arc_fill_flags_t flags = 0;
+
+ if (in_place)
+ flags |= ARC_FILL_IN_PLACE;
+
+ return (arc_buf_fill(buf, spa, dsobj, flags));
+}
+
+/*
+ * Increment the amount of evictable space in the arc_state_t's refcount.
+ * We account for the space used by the hdr and the arc buf individually
+ * so that we can add and remove them from the refcount individually.
+ */
+static void
+arc_evictable_space_increment(arc_buf_hdr_t *hdr, arc_state_t *state)
+{
+ arc_buf_contents_t type = arc_buf_type(hdr);
+ arc_buf_t *buf;
+
+ ASSERT(HDR_HAS_L1HDR(hdr));
+
+ if (GHOST_STATE(state)) {
+ ASSERT0(hdr->b_l1hdr.b_bufcnt);
+ ASSERT3P(hdr->b_l1hdr.b_buf, ==, NULL);
+ ASSERT3P(hdr->b_l1hdr.b_pabd, ==, NULL);
+ ASSERT(!HDR_HAS_RABD(hdr));
+ (void) refcount_add_many(&state->arcs_esize[type],
+ HDR_GET_LSIZE(hdr), hdr);
+ return;
+ }
+
+ ASSERT(!GHOST_STATE(state));
+ if (hdr->b_l1hdr.b_pabd != NULL) {
+ (void) refcount_add_many(&state->arcs_esize[type],
+ arc_hdr_size(hdr), hdr);
+ }
+ if (HDR_HAS_RABD(hdr)) {
+ (void) refcount_add_many(&state->arcs_esize[type],
+ HDR_GET_PSIZE(hdr), hdr);
+ }
+
+ for (buf = hdr->b_l1hdr.b_buf; buf != NULL; buf = buf->b_next) {
+ if (arc_buf_is_shared(buf))
+ continue;
+ (void) refcount_add_many(&state->arcs_esize[type],
+ arc_buf_size(buf), buf);
+ }
+}
+
+/*
+ * Decrement the amount of evictable space in the arc_state_t's refcount.
+ * We account for the space used by the hdr and the arc buf individually
+ * so that we can add and remove them from the refcount individually.
+ */
+static void
+arc_evictable_space_decrement(arc_buf_hdr_t *hdr, arc_state_t *state)
+{
+ arc_buf_contents_t type = arc_buf_type(hdr);
+ arc_buf_t *buf;
+
+ ASSERT(HDR_HAS_L1HDR(hdr));
+
+ if (GHOST_STATE(state)) {
+ ASSERT0(hdr->b_l1hdr.b_bufcnt);
+ ASSERT3P(hdr->b_l1hdr.b_buf, ==, NULL);
+ ASSERT3P(hdr->b_l1hdr.b_pabd, ==, NULL);
+ ASSERT(!HDR_HAS_RABD(hdr));
+ (void) refcount_remove_many(&state->arcs_esize[type],
+ HDR_GET_LSIZE(hdr), hdr);
+ return;
+ }
+
+ ASSERT(!GHOST_STATE(state));
+ if (hdr->b_l1hdr.b_pabd != NULL) {
+ (void) refcount_remove_many(&state->arcs_esize[type],
+ arc_hdr_size(hdr), hdr);
+ }
+ if (HDR_HAS_RABD(hdr)) {
+ (void) refcount_remove_many(&state->arcs_esize[type],
+ HDR_GET_PSIZE(hdr), hdr);
+ }
+
+ for (buf = hdr->b_l1hdr.b_buf; buf != NULL; buf = buf->b_next) {
+ if (arc_buf_is_shared(buf))
+ continue;
+ (void) refcount_remove_many(&state->arcs_esize[type],
+ arc_buf_size(buf), buf);
+ }
+}
+
+/*
+ * Add a reference to this hdr indicating that someone is actively
+ * referencing that memory. When the refcount transitions from 0 to 1,
+ * we remove it from the respective arc_state_t list to indicate that
+ * it is not evictable.
+ */
+static void
+add_reference(arc_buf_hdr_t *hdr, void *tag)
+{
+ arc_state_t *state;
+
+ ASSERT(HDR_HAS_L1HDR(hdr));
+ if (!MUTEX_HELD(HDR_LOCK(hdr))) {
+ ASSERT(hdr->b_l1hdr.b_state == arc_anon);
+ ASSERT(refcount_is_zero(&hdr->b_l1hdr.b_refcnt));
+ ASSERT3P(hdr->b_l1hdr.b_buf, ==, NULL);
+ }
+
+ state = hdr->b_l1hdr.b_state;
+
+ if ((refcount_add(&hdr->b_l1hdr.b_refcnt, tag) == 1) &&
+ (state != arc_anon)) {
+ /* We don't use the L2-only state list. */
+ if (state != arc_l2c_only) {
+ multilist_remove(state->arcs_list[arc_buf_type(hdr)],
+ hdr);
+ arc_evictable_space_decrement(hdr, state);
+ }
+ /* remove the prefetch flag if we get a reference */
+ arc_hdr_clear_flags(hdr, ARC_FLAG_PREFETCH);
+ }
+}
+
+/*
+ * Remove a reference from this hdr. When the reference transitions from
+ * 1 to 0 and we're not anonymous, then we add this hdr to the arc_state_t's
+ * list making it eligible for eviction.
+ */
+static int
+remove_reference(arc_buf_hdr_t *hdr, kmutex_t *hash_lock, void *tag)
+{
+ int cnt;
+ arc_state_t *state = hdr->b_l1hdr.b_state;
+
+ ASSERT(HDR_HAS_L1HDR(hdr));
+ ASSERT(state == arc_anon || MUTEX_HELD(hash_lock));
+ ASSERT(!GHOST_STATE(state));
+
+ /*
+ * arc_l2c_only counts as a ghost state so we don't need to explicitly
+ * check to prevent usage of the arc_l2c_only list.
+ */
+ if (((cnt = refcount_remove(&hdr->b_l1hdr.b_refcnt, tag)) == 0) &&
+ (state != arc_anon)) {
+ multilist_insert(state->arcs_list[arc_buf_type(hdr)], hdr);
+ ASSERT3U(hdr->b_l1hdr.b_bufcnt, >, 0);
+ arc_evictable_space_increment(hdr, state);
+ }
+ return (cnt);
+}
+
+/*
+ * Returns detailed information about a specific arc buffer. When the
+ * state_index argument is set the function will calculate the arc header
+ * list position for its arc state. Since this requires a linear traversal
+ * callers are strongly encourage not to do this. However, it can be helpful
+ * for targeted analysis so the functionality is provided.
+ */
+void
+arc_buf_info(arc_buf_t *ab, arc_buf_info_t *abi, int state_index)
+{
+ arc_buf_hdr_t *hdr = ab->b_hdr;
+ l1arc_buf_hdr_t *l1hdr = NULL;
+ l2arc_buf_hdr_t *l2hdr = NULL;
+ arc_state_t *state = NULL;
+
+ memset(abi, 0, sizeof (arc_buf_info_t));
+
+ if (hdr == NULL)
+ return;
+
+ abi->abi_flags = hdr->b_flags;
+
+ if (HDR_HAS_L1HDR(hdr)) {
+ l1hdr = &hdr->b_l1hdr;
+ state = l1hdr->b_state;
+ }
+ if (HDR_HAS_L2HDR(hdr))
+ l2hdr = &hdr->b_l2hdr;
+
+ if (l1hdr) {
+ abi->abi_bufcnt = l1hdr->b_bufcnt;
+ abi->abi_access = l1hdr->b_arc_access;
+ abi->abi_mru_hits = l1hdr->b_mru_hits;
+ abi->abi_mru_ghost_hits = l1hdr->b_mru_ghost_hits;
+ abi->abi_mfu_hits = l1hdr->b_mfu_hits;
+ abi->abi_mfu_ghost_hits = l1hdr->b_mfu_ghost_hits;
+ abi->abi_holds = refcount_count(&l1hdr->b_refcnt);
+ }
+
+ if (l2hdr) {
+ abi->abi_l2arc_dattr = l2hdr->b_daddr;
+ abi->abi_l2arc_hits = l2hdr->b_hits;
+ }
+
+ abi->abi_state_type = state ? state->arcs_state : ARC_STATE_ANON;
+ abi->abi_state_contents = arc_buf_type(hdr);
+ abi->abi_size = arc_hdr_size(hdr);
+}
+
+/*
+ * Move the supplied buffer to the indicated state. The hash lock
+ * for the buffer must be held by the caller.
+ */
+static void
+arc_change_state(arc_state_t *new_state, arc_buf_hdr_t *hdr,
+ kmutex_t *hash_lock)
+{
+ arc_state_t *old_state;
+ int64_t refcnt;
+ uint32_t bufcnt;
+ boolean_t update_old, update_new;
+ arc_buf_contents_t buftype = arc_buf_type(hdr);
+
+ /*
+ * We almost always have an L1 hdr here, since we call arc_hdr_realloc()
+ * in arc_read() when bringing a buffer out of the L2ARC. However, the
+ * L1 hdr doesn't always exist when we change state to arc_anon before
+ * destroying a header, in which case reallocating to add the L1 hdr is
+ * pointless.
+ */
+ if (HDR_HAS_L1HDR(hdr)) {
+ old_state = hdr->b_l1hdr.b_state;
+ refcnt = refcount_count(&hdr->b_l1hdr.b_refcnt);
+ bufcnt = hdr->b_l1hdr.b_bufcnt;
+ update_old = (bufcnt > 0 || hdr->b_l1hdr.b_pabd != NULL ||
+ HDR_HAS_RABD(hdr));
+ } else {
+ old_state = arc_l2c_only;
+ refcnt = 0;
+ bufcnt = 0;
+ update_old = B_FALSE;
+ }
+ update_new = update_old;
+
+ ASSERT(MUTEX_HELD(hash_lock));
+ ASSERT3P(new_state, !=, old_state);
+ ASSERT(!GHOST_STATE(new_state) || bufcnt == 0);
+ ASSERT(old_state != arc_anon || bufcnt <= 1);
+
+ /*
+ * If this buffer is evictable, transfer it from the
+ * old state list to the new state list.
+ */
+ if (refcnt == 0) {
+ if (old_state != arc_anon && old_state != arc_l2c_only) {
+ ASSERT(HDR_HAS_L1HDR(hdr));
+ multilist_remove(old_state->arcs_list[buftype], hdr);
+
+ if (GHOST_STATE(old_state)) {
+ ASSERT0(bufcnt);
+ ASSERT3P(hdr->b_l1hdr.b_buf, ==, NULL);
+ update_old = B_TRUE;
+ }
+ arc_evictable_space_decrement(hdr, old_state);
+ }
+ if (new_state != arc_anon && new_state != arc_l2c_only) {
+ /*
+ * An L1 header always exists here, since if we're
+ * moving to some L1-cached state (i.e. not l2c_only or
+ * anonymous), we realloc the header to add an L1hdr
+ * beforehand.
+ */
+ ASSERT(HDR_HAS_L1HDR(hdr));
+ multilist_insert(new_state->arcs_list[buftype], hdr);
+
+ if (GHOST_STATE(new_state)) {
+ ASSERT0(bufcnt);
+ ASSERT3P(hdr->b_l1hdr.b_buf, ==, NULL);
+ update_new = B_TRUE;
+ }
+ arc_evictable_space_increment(hdr, new_state);
+ }
+ }
+
+ ASSERT(!HDR_EMPTY(hdr));
+ if (new_state == arc_anon && HDR_IN_HASH_TABLE(hdr))
+ buf_hash_remove(hdr);
+
+ /* adjust state sizes (ignore arc_l2c_only) */
+
+ if (update_new && new_state != arc_l2c_only) {
+ ASSERT(HDR_HAS_L1HDR(hdr));
+ if (GHOST_STATE(new_state)) {
+ ASSERT0(bufcnt);
+
+ /*
+ * When moving a header to a ghost state, we first
+ * remove all arc buffers. Thus, we'll have a
+ * bufcnt of zero, and no arc buffer to use for
+ * the reference. As a result, we use the arc
+ * header pointer for the reference.
+ */
+ (void) refcount_add_many(&new_state->arcs_size,
+ HDR_GET_LSIZE(hdr), hdr);
+ ASSERT3P(hdr->b_l1hdr.b_pabd, ==, NULL);
+ ASSERT(!HDR_HAS_RABD(hdr));
+ } else {
+ arc_buf_t *buf;
+ uint32_t buffers = 0;
+
+ /*
+ * Each individual buffer holds a unique reference,
+ * thus we must remove each of these references one
+ * at a time.
+ */
+ for (buf = hdr->b_l1hdr.b_buf; buf != NULL;
+ buf = buf->b_next) {
+ ASSERT3U(bufcnt, !=, 0);
+ buffers++;
+
+ /*
+ * When the arc_buf_t is sharing the data
+ * block with the hdr, the owner of the
+ * reference belongs to the hdr. Only
+ * add to the refcount if the arc_buf_t is
+ * not shared.
+ */
+ if (arc_buf_is_shared(buf))
+ continue;
+
+ (void) refcount_add_many(&new_state->arcs_size,
+ arc_buf_size(buf), buf);
+ }
+ ASSERT3U(bufcnt, ==, buffers);
+
+ if (hdr->b_l1hdr.b_pabd != NULL) {
+ (void) refcount_add_many(&new_state->arcs_size,
+ arc_hdr_size(hdr), hdr);
+ }
+
+ if (HDR_HAS_RABD(hdr)) {
+ (void) refcount_add_many(&new_state->arcs_size,
+ HDR_GET_PSIZE(hdr), hdr);
+ }
+ }
+ }
+
+ if (update_old && old_state != arc_l2c_only) {
+ ASSERT(HDR_HAS_L1HDR(hdr));
+ if (GHOST_STATE(old_state)) {
+ ASSERT0(bufcnt);
+ ASSERT3P(hdr->b_l1hdr.b_pabd, ==, NULL);
+ ASSERT(!HDR_HAS_RABD(hdr));
+
+ /*
+ * When moving a header off of a ghost state,
+ * the header will not contain any arc buffers.
+ * We use the arc header pointer for the reference
+ * which is exactly what we did when we put the
+ * header on the ghost state.
+ */
+
+ (void) refcount_remove_many(&old_state->arcs_size,
+ HDR_GET_LSIZE(hdr), hdr);
+ } else {
+ arc_buf_t *buf;
+ uint32_t buffers = 0;
+
+ /*
+ * Each individual buffer holds a unique reference,
+ * thus we must remove each of these references one
+ * at a time.
+ */
+ for (buf = hdr->b_l1hdr.b_buf; buf != NULL;
+ buf = buf->b_next) {
+ ASSERT3U(bufcnt, !=, 0);
+ buffers++;
+
+ /*
+ * When the arc_buf_t is sharing the data
+ * block with the hdr, the owner of the
+ * reference belongs to the hdr. Only
+ * add to the refcount if the arc_buf_t is
+ * not shared.
+ */
+ if (arc_buf_is_shared(buf))
+ continue;
+
+ (void) refcount_remove_many(
+ &old_state->arcs_size, arc_buf_size(buf),
+ buf);
+ }
+ ASSERT3U(bufcnt, ==, buffers);
+ ASSERT(hdr->b_l1hdr.b_pabd != NULL ||
+ HDR_HAS_RABD(hdr));
+
+ if (hdr->b_l1hdr.b_pabd != NULL) {
+ (void) refcount_remove_many(
+ &old_state->arcs_size, arc_hdr_size(hdr),
+ hdr);
+ }
+
+ if (HDR_HAS_RABD(hdr)) {
+ (void) refcount_remove_many(
+ &old_state->arcs_size, HDR_GET_PSIZE(hdr),
+ hdr);
+ }
+ }
+ }
+
+ if (HDR_HAS_L1HDR(hdr))
+ hdr->b_l1hdr.b_state = new_state;
+
+ /*
+ * L2 headers should never be on the L2 state list since they don't
+ * have L1 headers allocated.
+ */
+ ASSERT(multilist_is_empty(arc_l2c_only->arcs_list[ARC_BUFC_DATA]) &&
+ multilist_is_empty(arc_l2c_only->arcs_list[ARC_BUFC_METADATA]));
+}
+
+void
+arc_space_consume(uint64_t space, arc_space_type_t type)
+{
+ ASSERT(type >= 0 && type < ARC_SPACE_NUMTYPES);
+
+ switch (type) {
+ default:
+ break;
+ case ARC_SPACE_DATA:
+ ARCSTAT_INCR(arcstat_data_size, space);
+ break;
+ case ARC_SPACE_META:
+ ARCSTAT_INCR(arcstat_metadata_size, space);
+ break;
+ case ARC_SPACE_BONUS:
+ ARCSTAT_INCR(arcstat_bonus_size, space);
+ break;
+ case ARC_SPACE_DNODE:
+ ARCSTAT_INCR(arcstat_dnode_size, space);
+ break;
+ case ARC_SPACE_DBUF:
+ ARCSTAT_INCR(arcstat_dbuf_size, space);
+ break;
+ case ARC_SPACE_HDRS:
+ ARCSTAT_INCR(arcstat_hdr_size, space);
+ break;
+ case ARC_SPACE_L2HDRS:
+ ARCSTAT_INCR(arcstat_l2_hdr_size, space);
+ break;
+ }
+
+ if (type != ARC_SPACE_DATA)
+ ARCSTAT_INCR(arcstat_meta_used, space);
+
+ atomic_add_64(&arc_size, space);
+}
+
+void
+arc_space_return(uint64_t space, arc_space_type_t type)
+{
+ ASSERT(type >= 0 && type < ARC_SPACE_NUMTYPES);
+
+ switch (type) {
+ default:
+ break;
case ARC_SPACE_DATA:
ARCSTAT_INCR(arcstat_data_size, -space);
break;
case ARC_SPACE_META:
- ARCSTAT_INCR(arcstat_meta_size, -space);
+ ARCSTAT_INCR(arcstat_metadata_size, -space);
+ break;
+ case ARC_SPACE_BONUS:
+ ARCSTAT_INCR(arcstat_bonus_size, -space);
break;
- case ARC_SPACE_OTHER:
- ARCSTAT_INCR(arcstat_other_size, -space);
+ case ARC_SPACE_DNODE:
+ ARCSTAT_INCR(arcstat_dnode_size, -space);
+ break;
+ case ARC_SPACE_DBUF:
+ ARCSTAT_INCR(arcstat_dbuf_size, -space);
break;
case ARC_SPACE_HDRS:
ARCSTAT_INCR(arcstat_hdr_size, -space);
if (type != ARC_SPACE_DATA) {
ASSERT(arc_meta_used >= space);
+ if (arc_meta_max < arc_meta_used)
+ arc_meta_max = arc_meta_used;
ARCSTAT_INCR(arcstat_meta_used, -space);
}
atomic_add_64(&arc_size, -space);
}
-arc_buf_t *
-arc_buf_alloc(spa_t *spa, uint64_t size, void *tag, arc_buf_contents_t type)
+/*
+ * Given a hdr and a buf, returns whether that buf can share its b_data buffer
+ * with the hdr's b_pabd.
+ */
+static boolean_t
+arc_can_share(arc_buf_hdr_t *hdr, arc_buf_t *buf)
+{
+ /*
+ * The criteria for sharing a hdr's data are:
+ * 1. the buffer is not encrypted
+ * 2. the hdr's compression matches the buf's compression
+ * 3. the hdr doesn't need to be byteswapped
+ * 4. the hdr isn't already being shared
+ * 5. the buf is either compressed or it is the last buf in the hdr list
+ *
+ * Criterion #5 maintains the invariant that shared uncompressed
+ * bufs must be the final buf in the hdr's b_buf list. Reading this, you
+ * might ask, "if a compressed buf is allocated first, won't that be the
+ * last thing in the list?", but in that case it's impossible to create
+ * a shared uncompressed buf anyway (because the hdr must be compressed
+ * to have the compressed buf). You might also think that #3 is
+ * sufficient to make this guarantee, however it's possible
+ * (specifically in the rare L2ARC write race mentioned in
+ * arc_buf_alloc_impl()) there will be an existing uncompressed buf that
+ * is sharable, but wasn't at the time of its allocation. Rather than
+ * allow a new shared uncompressed buf to be created and then shuffle
+ * the list around to make it the last element, this simply disallows
+ * sharing if the new buf isn't the first to be added.
+ */
+ ASSERT3P(buf->b_hdr, ==, hdr);
+ boolean_t hdr_compressed =
+ arc_hdr_get_compress(hdr) != ZIO_COMPRESS_OFF;
+ boolean_t buf_compressed = ARC_BUF_COMPRESSED(buf) != 0;
+ return (!ARC_BUF_ENCRYPTED(buf) &&
+ buf_compressed == hdr_compressed &&
+ hdr->b_l1hdr.b_byteswap == DMU_BSWAP_NUMFUNCS &&
+ !HDR_SHARED_DATA(hdr) &&
+ (ARC_BUF_LAST(buf) || ARC_BUF_COMPRESSED(buf)));
+}
+
+/*
+ * Allocate a buf for this hdr. If you care about the data that's in the hdr,
+ * or if you want a compressed buffer, pass those flags in. Returns 0 if the
+ * copy was made successfully, or an error code otherwise.
+ */
+static int
+arc_buf_alloc_impl(arc_buf_hdr_t *hdr, spa_t *spa, uint64_t dsobj, void *tag,
+ boolean_t encrypted, boolean_t compressed, boolean_t noauth,
+ boolean_t fill, arc_buf_t **ret)
{
- arc_buf_hdr_t *hdr;
arc_buf_t *buf;
+ arc_fill_flags_t flags = ARC_FILL_LOCKED;
+
+ ASSERT(HDR_HAS_L1HDR(hdr));
+ ASSERT3U(HDR_GET_LSIZE(hdr), >, 0);
+ VERIFY(hdr->b_type == ARC_BUFC_DATA ||
+ hdr->b_type == ARC_BUFC_METADATA);
+ ASSERT3P(ret, !=, NULL);
+ ASSERT3P(*ret, ==, NULL);
+ IMPLY(encrypted, compressed);
- VERIFY3U(size, <=, spa_maxblocksize(spa));
- hdr = kmem_cache_alloc(hdr_full_cache, KM_PUSHPAGE);
- ASSERT(BUF_EMPTY(hdr));
- ASSERT3P(hdr->b_freeze_cksum, ==, NULL);
- hdr->b_size = size;
- hdr->b_spa = spa_load_guid(spa);
hdr->b_l1hdr.b_mru_hits = 0;
hdr->b_l1hdr.b_mru_ghost_hits = 0;
hdr->b_l1hdr.b_mfu_hits = 0;
hdr->b_l1hdr.b_mfu_ghost_hits = 0;
hdr->b_l1hdr.b_l2_hits = 0;
- buf = kmem_cache_alloc(buf_cache, KM_PUSHPAGE);
+ buf = *ret = kmem_cache_alloc(buf_cache, KM_PUSHPAGE);
buf->b_hdr = hdr;
buf->b_data = NULL;
- buf->b_efunc = NULL;
- buf->b_private = NULL;
- buf->b_next = NULL;
+ buf->b_next = hdr->b_l1hdr.b_buf;
+ buf->b_flags = 0;
- hdr->b_flags = arc_bufc_to_flags(type);
- hdr->b_flags |= ARC_FLAG_HAS_L1HDR;
+ add_reference(hdr, tag);
- hdr->b_l1hdr.b_buf = buf;
- hdr->b_l1hdr.b_state = arc_anon;
- hdr->b_l1hdr.b_arc_access = 0;
- hdr->b_l1hdr.b_datacnt = 1;
- hdr->b_l1hdr.b_tmp_cdata = NULL;
+ /*
+ * We're about to change the hdr's b_flags. We must either
+ * hold the hash_lock or be undiscoverable.
+ */
+ ASSERT(MUTEX_HELD(HDR_LOCK(hdr)) || HDR_EMPTY(hdr));
- arc_get_data_buf(buf);
+ /*
+ * Only honor requests for compressed bufs if the hdr is actually
+ * compressed. This must be overriden if the buffer is encrypted since
+ * encrypted buffers cannot be decompressed.
+ */
+ if (encrypted) {
+ buf->b_flags |= ARC_BUF_FLAG_COMPRESSED;
+ buf->b_flags |= ARC_BUF_FLAG_ENCRYPTED;
+ flags |= ARC_FILL_COMPRESSED | ARC_FILL_ENCRYPTED;
+ } else if (compressed &&
+ arc_hdr_get_compress(hdr) != ZIO_COMPRESS_OFF) {
+ buf->b_flags |= ARC_BUF_FLAG_COMPRESSED;
+ flags |= ARC_FILL_COMPRESSED;
+ }
- ASSERT(refcount_is_zero(&hdr->b_l1hdr.b_refcnt));
- (void) refcount_add(&hdr->b_l1hdr.b_refcnt, tag);
+ if (noauth) {
+ ASSERT0(encrypted);
+ flags |= ARC_FILL_NOAUTH;
+ }
- return (buf);
+ /*
+ * If the hdr's data can be shared then we share the data buffer and
+ * set the appropriate bit in the hdr's b_flags to indicate the hdr is
+ * allocate a new buffer to store the buf's data.
+ *
+ * There are two additional restrictions here because we're sharing
+ * hdr -> buf instead of the usual buf -> hdr. First, the hdr can't be
+ * actively involved in an L2ARC write, because if this buf is used by
+ * an arc_write() then the hdr's data buffer will be released when the
+ * write completes, even though the L2ARC write might still be using it.
+ * Second, the hdr's ABD must be linear so that the buf's user doesn't
+ * need to be ABD-aware.
+ */
+ boolean_t can_share = arc_can_share(hdr, buf) && !HDR_L2_WRITING(hdr) &&
+ hdr->b_l1hdr.b_pabd != NULL && abd_is_linear(hdr->b_l1hdr.b_pabd);
+
+ /* Set up b_data and sharing */
+ if (can_share) {
+ buf->b_data = abd_to_buf(hdr->b_l1hdr.b_pabd);
+ buf->b_flags |= ARC_BUF_FLAG_SHARED;
+ arc_hdr_set_flags(hdr, ARC_FLAG_SHARED_DATA);
+ } else {
+ buf->b_data =
+ arc_get_data_buf(hdr, arc_buf_size(buf), buf);
+ ARCSTAT_INCR(arcstat_overhead_size, arc_buf_size(buf));
+ }
+ VERIFY3P(buf->b_data, !=, NULL);
+
+ hdr->b_l1hdr.b_buf = buf;
+ hdr->b_l1hdr.b_bufcnt += 1;
+ if (encrypted)
+ hdr->b_crypt_hdr.b_ebufcnt += 1;
+
+ /*
+ * If the user wants the data from the hdr, we need to either copy or
+ * decompress the data.
+ */
+ if (fill) {
+ return (arc_buf_fill(buf, spa, dsobj, flags));
+ }
+
+ return (0);
}
-static char *arc_onloan_tag = "onloan";
+static char *arc_onloan_tag = "onloan";
+
+static inline void
+arc_loaned_bytes_update(int64_t delta)
+{
+ atomic_add_64(&arc_loaned_bytes, delta);
+
+ /* assert that it did not wrap around */
+ ASSERT3S(atomic_add_64_nv(&arc_loaned_bytes, 0), >=, 0);
+}
/*
* Loan out an anonymous arc buffer. Loaned buffers are not counted as in
* freed.
*/
arc_buf_t *
-arc_loan_buf(spa_t *spa, uint64_t size)
+arc_loan_buf(spa_t *spa, boolean_t is_metadata, int size)
{
- arc_buf_t *buf;
+ arc_buf_t *buf = arc_alloc_buf(spa, arc_onloan_tag,
+ is_metadata ? ARC_BUFC_METADATA : ARC_BUFC_DATA, size);
+
+ arc_loaned_bytes_update(size);
+
+ return (buf);
+}
+
+arc_buf_t *
+arc_loan_compressed_buf(spa_t *spa, uint64_t psize, uint64_t lsize,
+ enum zio_compress compression_type)
+{
+ arc_buf_t *buf = arc_alloc_compressed_buf(spa, arc_onloan_tag,
+ psize, lsize, compression_type);
+
+ arc_loaned_bytes_update(psize);
+
+ return (buf);
+}
- buf = arc_buf_alloc(spa, size, arc_onloan_tag, ARC_BUFC_DATA);
+arc_buf_t *
+arc_loan_raw_buf(spa_t *spa, uint64_t dsobj, boolean_t byteorder,
+ const uint8_t *salt, const uint8_t *iv, const uint8_t *mac,
+ dmu_object_type_t ot, uint64_t psize, uint64_t lsize,
+ enum zio_compress compression_type)
+{
+ arc_buf_t *buf = arc_alloc_raw_buf(spa, arc_onloan_tag, dsobj,
+ byteorder, salt, iv, mac, ot, psize, lsize, compression_type);
- atomic_add_64(&arc_loaned_bytes, size);
+ atomic_add_64(&arc_loaned_bytes, psize);
return (buf);
}
+
/*
* Return a loaned arc buffer to the arc.
*/
{
arc_buf_hdr_t *hdr = buf->b_hdr;
- ASSERT(buf->b_data != NULL);
+ ASSERT3P(buf->b_data, !=, NULL);
ASSERT(HDR_HAS_L1HDR(hdr));
(void) refcount_add(&hdr->b_l1hdr.b_refcnt, tag);
(void) refcount_remove(&hdr->b_l1hdr.b_refcnt, arc_onloan_tag);
- atomic_add_64(&arc_loaned_bytes, -hdr->b_size);
+ arc_loaned_bytes_update(-arc_buf_size(buf));
}
/* Detach an arc_buf from a dbuf (tag) */
{
arc_buf_hdr_t *hdr = buf->b_hdr;
- ASSERT(buf->b_data != NULL);
+ ASSERT3P(buf->b_data, !=, NULL);
ASSERT(HDR_HAS_L1HDR(hdr));
(void) refcount_add(&hdr->b_l1hdr.b_refcnt, arc_onloan_tag);
(void) refcount_remove(&hdr->b_l1hdr.b_refcnt, tag);
- buf->b_efunc = NULL;
- buf->b_private = NULL;
- atomic_add_64(&arc_loaned_bytes, hdr->b_size);
+ arc_loaned_bytes_update(arc_buf_size(buf));
}
-static arc_buf_t *
-arc_buf_clone(arc_buf_t *from)
+static void
+l2arc_free_abd_on_write(abd_t *abd, size_t size, arc_buf_contents_t type)
{
- arc_buf_t *buf;
- arc_buf_hdr_t *hdr = from->b_hdr;
- uint64_t size = hdr->b_size;
+ l2arc_data_free_t *df = kmem_alloc(sizeof (*df), KM_SLEEP);
+
+ df->l2df_abd = abd;
+ df->l2df_size = size;
+ df->l2df_type = type;
+ mutex_enter(&l2arc_free_on_write_mtx);
+ list_insert_head(l2arc_free_on_write, df);
+ mutex_exit(&l2arc_free_on_write_mtx);
+}
+
+static void
+arc_hdr_free_on_write(arc_buf_hdr_t *hdr, boolean_t free_rdata)
+{
+ arc_state_t *state = hdr->b_l1hdr.b_state;
+ arc_buf_contents_t type = arc_buf_type(hdr);
+ uint64_t size = (free_rdata) ? HDR_GET_PSIZE(hdr) : arc_hdr_size(hdr);
+
+ /* protected by hash lock, if in the hash table */
+ if (multilist_link_active(&hdr->b_l1hdr.b_arc_node)) {
+ ASSERT(refcount_is_zero(&hdr->b_l1hdr.b_refcnt));
+ ASSERT(state != arc_anon && state != arc_l2c_only);
+
+ (void) refcount_remove_many(&state->arcs_esize[type],
+ size, hdr);
+ }
+ (void) refcount_remove_many(&state->arcs_size, size, hdr);
+ if (type == ARC_BUFC_METADATA) {
+ arc_space_return(size, ARC_SPACE_META);
+ } else {
+ ASSERT(type == ARC_BUFC_DATA);
+ arc_space_return(size, ARC_SPACE_DATA);
+ }
+
+ if (free_rdata) {
+ l2arc_free_abd_on_write(hdr->b_crypt_hdr.b_rabd, size, type);
+ } else {
+ l2arc_free_abd_on_write(hdr->b_l1hdr.b_pabd, size, type);
+ }
+}
+
+/*
+ * Share the arc_buf_t's data with the hdr. Whenever we are sharing the
+ * data buffer, we transfer the refcount ownership to the hdr and update
+ * the appropriate kstats.
+ */
+static void
+arc_share_buf(arc_buf_hdr_t *hdr, arc_buf_t *buf)
+{
+ ASSERT(arc_can_share(hdr, buf));
+ ASSERT3P(hdr->b_l1hdr.b_pabd, ==, NULL);
+ ASSERT(!ARC_BUF_ENCRYPTED(buf));
+ ASSERT(MUTEX_HELD(HDR_LOCK(hdr)) || HDR_EMPTY(hdr));
+
+ /*
+ * Start sharing the data buffer. We transfer the
+ * refcount ownership to the hdr since it always owns
+ * the refcount whenever an arc_buf_t is shared.
+ */
+ refcount_transfer_ownership(&hdr->b_l1hdr.b_state->arcs_size, buf, hdr);
+ hdr->b_l1hdr.b_pabd = abd_get_from_buf(buf->b_data, arc_buf_size(buf));
+ abd_take_ownership_of_buf(hdr->b_l1hdr.b_pabd,
+ HDR_ISTYPE_METADATA(hdr));
+ arc_hdr_set_flags(hdr, ARC_FLAG_SHARED_DATA);
+ buf->b_flags |= ARC_BUF_FLAG_SHARED;
+
+ /*
+ * Since we've transferred ownership to the hdr we need
+ * to increment its compressed and uncompressed kstats and
+ * decrement the overhead size.
+ */
+ ARCSTAT_INCR(arcstat_compressed_size, arc_hdr_size(hdr));
+ ARCSTAT_INCR(arcstat_uncompressed_size, HDR_GET_LSIZE(hdr));
+ ARCSTAT_INCR(arcstat_overhead_size, -arc_buf_size(buf));
+}
+
+static void
+arc_unshare_buf(arc_buf_hdr_t *hdr, arc_buf_t *buf)
+{
+ ASSERT(arc_buf_is_shared(buf));
+ ASSERT3P(hdr->b_l1hdr.b_pabd, !=, NULL);
+ ASSERT(MUTEX_HELD(HDR_LOCK(hdr)) || HDR_EMPTY(hdr));
+
+ /*
+ * We are no longer sharing this buffer so we need
+ * to transfer its ownership to the rightful owner.
+ */
+ refcount_transfer_ownership(&hdr->b_l1hdr.b_state->arcs_size, hdr, buf);
+ arc_hdr_clear_flags(hdr, ARC_FLAG_SHARED_DATA);
+ abd_release_ownership_of_buf(hdr->b_l1hdr.b_pabd);
+ abd_put(hdr->b_l1hdr.b_pabd);
+ hdr->b_l1hdr.b_pabd = NULL;
+ buf->b_flags &= ~ARC_BUF_FLAG_SHARED;
+
+ /*
+ * Since the buffer is no longer shared between
+ * the arc buf and the hdr, count it as overhead.
+ */
+ ARCSTAT_INCR(arcstat_compressed_size, -arc_hdr_size(hdr));
+ ARCSTAT_INCR(arcstat_uncompressed_size, -HDR_GET_LSIZE(hdr));
+ ARCSTAT_INCR(arcstat_overhead_size, arc_buf_size(buf));
+}
+/*
+ * Remove an arc_buf_t from the hdr's buf list and return the last
+ * arc_buf_t on the list. If no buffers remain on the list then return
+ * NULL.
+ */
+static arc_buf_t *
+arc_buf_remove(arc_buf_hdr_t *hdr, arc_buf_t *buf)
+{
ASSERT(HDR_HAS_L1HDR(hdr));
- ASSERT(hdr->b_l1hdr.b_state != arc_anon);
+ ASSERT(MUTEX_HELD(HDR_LOCK(hdr)) || HDR_EMPTY(hdr));
- buf = kmem_cache_alloc(buf_cache, KM_PUSHPAGE);
- buf->b_hdr = hdr;
- buf->b_data = NULL;
- buf->b_efunc = NULL;
- buf->b_private = NULL;
- buf->b_next = hdr->b_l1hdr.b_buf;
- hdr->b_l1hdr.b_buf = buf;
- arc_get_data_buf(buf);
- bcopy(from->b_data, buf->b_data, size);
+ arc_buf_t **bufp = &hdr->b_l1hdr.b_buf;
+ arc_buf_t *lastbuf = NULL;
/*
- * This buffer already exists in the arc so create a duplicate
- * copy for the caller. If the buffer is associated with user data
- * then track the size and number of duplicates. These stats will be
- * updated as duplicate buffers are created and destroyed.
+ * Remove the buf from the hdr list and locate the last
+ * remaining buffer on the list.
*/
- if (HDR_ISTYPE_DATA(hdr)) {
- ARCSTAT_BUMP(arcstat_duplicate_buffers);
- ARCSTAT_INCR(arcstat_duplicate_buffers_size, size);
+ while (*bufp != NULL) {
+ if (*bufp == buf)
+ *bufp = buf->b_next;
+
+ /*
+ * If we've removed a buffer in the middle of
+ * the list then update the lastbuf and update
+ * bufp.
+ */
+ if (*bufp != NULL) {
+ lastbuf = *bufp;
+ bufp = &(*bufp)->b_next;
+ }
}
- hdr->b_l1hdr.b_datacnt += 1;
- return (buf);
+ buf->b_next = NULL;
+ ASSERT3P(lastbuf, !=, buf);
+ IMPLY(hdr->b_l1hdr.b_bufcnt > 0, lastbuf != NULL);
+ IMPLY(hdr->b_l1hdr.b_bufcnt > 0, hdr->b_l1hdr.b_buf != NULL);
+ IMPLY(lastbuf != NULL, ARC_BUF_LAST(lastbuf));
+
+ return (lastbuf);
}
-void
-arc_buf_add_ref(arc_buf_t *buf, void* tag)
+/*
+ * Free up buf->b_data and pull the arc_buf_t off of the the arc_buf_hdr_t's
+ * list and free it.
+ */
+static void
+arc_buf_destroy_impl(arc_buf_t *buf)
{
- arc_buf_hdr_t *hdr;
- kmutex_t *hash_lock;
+ arc_buf_hdr_t *hdr = buf->b_hdr;
/*
- * Check to see if this buffer is evicted. Callers
- * must verify b_data != NULL to know if the add_ref
- * was successful.
+ * Free up the data associated with the buf but only if we're not
+ * sharing this with the hdr. If we are sharing it with the hdr, the
+ * hdr is responsible for doing the free.
*/
- mutex_enter(&buf->b_evict_lock);
- if (buf->b_data == NULL) {
- mutex_exit(&buf->b_evict_lock);
- return;
+ if (buf->b_data != NULL) {
+ /*
+ * We're about to change the hdr's b_flags. We must either
+ * hold the hash_lock or be undiscoverable.
+ */
+ ASSERT(MUTEX_HELD(HDR_LOCK(hdr)) || HDR_EMPTY(hdr));
+
+ arc_cksum_verify(buf);
+ arc_buf_unwatch(buf);
+
+ if (arc_buf_is_shared(buf)) {
+ arc_hdr_clear_flags(hdr, ARC_FLAG_SHARED_DATA);
+ } else {
+ uint64_t size = arc_buf_size(buf);
+ arc_free_data_buf(hdr, buf->b_data, size, buf);
+ ARCSTAT_INCR(arcstat_overhead_size, -size);
+ }
+ buf->b_data = NULL;
+
+ ASSERT(hdr->b_l1hdr.b_bufcnt > 0);
+ hdr->b_l1hdr.b_bufcnt -= 1;
+
+ if (ARC_BUF_ENCRYPTED(buf))
+ hdr->b_crypt_hdr.b_ebufcnt -= 1;
+
+ /*
+ * if we have no more encrypted buffers and we've already
+ * gotten a copy of the decrypted data we can free b_rabd to
+ * save some space.
+ */
+ if (hdr->b_crypt_hdr.b_ebufcnt == 0 && HDR_HAS_RABD(hdr) &&
+ hdr->b_l1hdr.b_pabd != NULL)
+ arc_hdr_free_abd(hdr, B_TRUE);
}
- hash_lock = HDR_LOCK(buf->b_hdr);
- mutex_enter(hash_lock);
- hdr = buf->b_hdr;
- ASSERT(HDR_HAS_L1HDR(hdr));
- ASSERT3P(hash_lock, ==, HDR_LOCK(hdr));
- mutex_exit(&buf->b_evict_lock);
- ASSERT(hdr->b_l1hdr.b_state == arc_mru ||
- hdr->b_l1hdr.b_state == arc_mfu);
+ arc_buf_t *lastbuf = arc_buf_remove(hdr, buf);
- add_reference(hdr, hash_lock, tag);
- DTRACE_PROBE1(arc__hit, arc_buf_hdr_t *, hdr);
- arc_access(hdr, hash_lock);
- mutex_exit(hash_lock);
- ARCSTAT_BUMP(arcstat_hits);
- ARCSTAT_CONDSTAT(!HDR_PREFETCH(hdr),
- demand, prefetch, !HDR_ISTYPE_METADATA(hdr),
- data, metadata, hits);
+ if (ARC_BUF_SHARED(buf) && !ARC_BUF_COMPRESSED(buf)) {
+ /*
+ * If the current arc_buf_t is sharing its data buffer with the
+ * hdr, then reassign the hdr's b_pabd to share it with the new
+ * buffer at the end of the list. The shared buffer is always
+ * the last one on the hdr's buffer list.
+ *
+ * There is an equivalent case for compressed bufs, but since
+ * they aren't guaranteed to be the last buf in the list and
+ * that is an exceedingly rare case, we just allow that space be
+ * wasted temporarily. We must also be careful not to share
+ * encrypted buffers, since they cannot be shared.
+ */
+ if (lastbuf != NULL && !ARC_BUF_ENCRYPTED(lastbuf)) {
+ /* Only one buf can be shared at once */
+ VERIFY(!arc_buf_is_shared(lastbuf));
+ /* hdr is uncompressed so can't have compressed buf */
+ VERIFY(!ARC_BUF_COMPRESSED(lastbuf));
+
+ ASSERT3P(hdr->b_l1hdr.b_pabd, !=, NULL);
+ arc_hdr_free_abd(hdr, B_FALSE);
+
+ /*
+ * We must setup a new shared block between the
+ * last buffer and the hdr. The data would have
+ * been allocated by the arc buf so we need to transfer
+ * ownership to the hdr since it's now being shared.
+ */
+ arc_share_buf(hdr, lastbuf);
+ }
+ } else if (HDR_SHARED_DATA(hdr)) {
+ /*
+ * Uncompressed shared buffers are always at the end
+ * of the list. Compressed buffers don't have the
+ * same requirements. This makes it hard to
+ * simply assert that the lastbuf is shared so
+ * we rely on the hdr's compression flags to determine
+ * if we have a compressed, shared buffer.
+ */
+ ASSERT3P(lastbuf, !=, NULL);
+ ASSERT(arc_buf_is_shared(lastbuf) ||
+ arc_hdr_get_compress(hdr) != ZIO_COMPRESS_OFF);
+ }
+
+ /*
+ * Free the checksum if we're removing the last uncompressed buf from
+ * this hdr.
+ */
+ if (!arc_hdr_has_uncompressed_buf(hdr)) {
+ arc_cksum_free(hdr);
+ }
+
+ /* clean up the buf */
+ buf->b_hdr = NULL;
+ kmem_cache_free(buf_cache, buf);
}
static void
-arc_buf_free_on_write(void *data, size_t size,
- void (*free_func)(void *, size_t))
+arc_hdr_alloc_abd(arc_buf_hdr_t *hdr, boolean_t alloc_rdata)
{
- l2arc_data_free_t *df;
+ uint64_t size;
- df = kmem_alloc(sizeof (*df), KM_SLEEP);
- df->l2df_data = data;
- df->l2df_size = size;
- df->l2df_func = free_func;
- mutex_enter(&l2arc_free_on_write_mtx);
- list_insert_head(l2arc_free_on_write, df);
- mutex_exit(&l2arc_free_on_write_mtx);
+ ASSERT3U(HDR_GET_LSIZE(hdr), >, 0);
+ ASSERT(HDR_HAS_L1HDR(hdr));
+ ASSERT(!HDR_SHARED_DATA(hdr) || alloc_rdata);
+ IMPLY(alloc_rdata, HDR_PROTECTED(hdr));
+
+ if (hdr->b_l1hdr.b_pabd == NULL && !HDR_HAS_RABD(hdr))
+ hdr->b_l1hdr.b_byteswap = DMU_BSWAP_NUMFUNCS;
+
+ if (alloc_rdata) {
+ size = HDR_GET_PSIZE(hdr);
+ ASSERT3P(hdr->b_crypt_hdr.b_rabd, ==, NULL);
+ hdr->b_crypt_hdr.b_rabd = arc_get_data_abd(hdr, size, hdr);
+ ASSERT3P(hdr->b_crypt_hdr.b_rabd, !=, NULL);
+ ARCSTAT_INCR(arcstat_raw_size, size);
+ } else {
+ size = arc_hdr_size(hdr);
+ ASSERT3P(hdr->b_l1hdr.b_pabd, ==, NULL);
+ hdr->b_l1hdr.b_pabd = arc_get_data_abd(hdr, size, hdr);
+ ASSERT3P(hdr->b_l1hdr.b_pabd, !=, NULL);
+ }
+
+ ARCSTAT_INCR(arcstat_compressed_size, size);
+ ARCSTAT_INCR(arcstat_uncompressed_size, HDR_GET_LSIZE(hdr));
}
-/*
- * Free the arc data buffer. If it is an l2arc write in progress,
- * the buffer is placed on l2arc_free_on_write to be freed later.
- */
static void
-arc_buf_data_free(arc_buf_t *buf, void (*free_func)(void *, size_t))
+arc_hdr_free_abd(arc_buf_hdr_t *hdr, boolean_t free_rdata)
{
- arc_buf_hdr_t *hdr = buf->b_hdr;
+ uint64_t size = (free_rdata) ? HDR_GET_PSIZE(hdr) : arc_hdr_size(hdr);
+
+ ASSERT(HDR_HAS_L1HDR(hdr));
+ ASSERT(hdr->b_l1hdr.b_pabd != NULL || HDR_HAS_RABD(hdr));
+ IMPLY(free_rdata, HDR_HAS_RABD(hdr));
+ /*
+ * If the hdr is currently being written to the l2arc then
+ * we defer freeing the data by adding it to the l2arc_free_on_write
+ * list. The l2arc will free the data once it's finished
+ * writing it to the l2arc device.
+ */
if (HDR_L2_WRITING(hdr)) {
- arc_buf_free_on_write(buf->b_data, hdr->b_size, free_func);
+ arc_hdr_free_on_write(hdr, free_rdata);
ARCSTAT_BUMP(arcstat_l2_free_on_write);
+ } else if (free_rdata) {
+ arc_free_data_abd(hdr, hdr->b_crypt_hdr.b_rabd, size, hdr);
+ } else {
+ arc_free_data_abd(hdr, hdr->b_l1hdr.b_pabd, size, hdr);
+ }
+
+ if (free_rdata) {
+ hdr->b_crypt_hdr.b_rabd = NULL;
+ ARCSTAT_INCR(arcstat_raw_size, -size);
} else {
- free_func(buf->b_data, hdr->b_size);
+ hdr->b_l1hdr.b_pabd = NULL;
}
+
+ if (hdr->b_l1hdr.b_pabd == NULL && !HDR_HAS_RABD(hdr))
+ hdr->b_l1hdr.b_byteswap = DMU_BSWAP_NUMFUNCS;
+
+ ARCSTAT_INCR(arcstat_compressed_size, -size);
+ ARCSTAT_INCR(arcstat_uncompressed_size, -HDR_GET_LSIZE(hdr));
}
-static void
-arc_buf_l2_cdata_free(arc_buf_hdr_t *hdr)
+static arc_buf_hdr_t *
+arc_hdr_alloc(uint64_t spa, int32_t psize, int32_t lsize,
+ boolean_t protected, enum zio_compress compression_type,
+ arc_buf_contents_t type, boolean_t alloc_rdata)
{
- ASSERT(HDR_HAS_L2HDR(hdr));
- ASSERT(MUTEX_HELD(&hdr->b_l2hdr.b_dev->l2ad_mtx));
+ arc_buf_hdr_t *hdr;
+
+ VERIFY(type == ARC_BUFC_DATA || type == ARC_BUFC_METADATA);
+ if (protected) {
+ hdr = kmem_cache_alloc(hdr_full_crypt_cache, KM_PUSHPAGE);
+ } else {
+ hdr = kmem_cache_alloc(hdr_full_cache, KM_PUSHPAGE);
+ }
+
+ ASSERT(HDR_EMPTY(hdr));
+ ASSERT3P(hdr->b_l1hdr.b_freeze_cksum, ==, NULL);
+ HDR_SET_PSIZE(hdr, psize);
+ HDR_SET_LSIZE(hdr, lsize);
+ hdr->b_spa = spa;
+ hdr->b_type = type;
+ hdr->b_flags = 0;
+ arc_hdr_set_flags(hdr, arc_bufc_to_flags(type) | ARC_FLAG_HAS_L1HDR);
+ arc_hdr_set_compress(hdr, compression_type);
+ if (protected)
+ arc_hdr_set_flags(hdr, ARC_FLAG_PROTECTED);
+
+ hdr->b_l1hdr.b_state = arc_anon;
+ hdr->b_l1hdr.b_arc_access = 0;
+ hdr->b_l1hdr.b_bufcnt = 0;
+ hdr->b_l1hdr.b_buf = NULL;
/*
- * The b_tmp_cdata field is linked off of the b_l1hdr, so if
- * that doesn't exist, the header is in the arc_l2c_only state,
- * and there isn't anything to free (it's already been freed).
+ * Allocate the hdr's buffer. This will contain either
+ * the compressed or uncompressed data depending on the block
+ * it references and compressed arc enablement.
*/
- if (!HDR_HAS_L1HDR(hdr))
- return;
+ arc_hdr_alloc_abd(hdr, alloc_rdata);
+ ASSERT(refcount_is_zero(&hdr->b_l1hdr.b_refcnt));
+
+ return (hdr);
+}
+
+/*
+ * Transition between the two allocation states for the arc_buf_hdr struct.
+ * The arc_buf_hdr struct can be allocated with (hdr_full_cache) or without
+ * (hdr_l2only_cache) the fields necessary for the L1 cache - the smaller
+ * version is used when a cache buffer is only in the L2ARC in order to reduce
+ * memory usage.
+ */
+static arc_buf_hdr_t *
+arc_hdr_realloc(arc_buf_hdr_t *hdr, kmem_cache_t *old, kmem_cache_t *new)
+{
+ arc_buf_hdr_t *nhdr;
+ l2arc_dev_t *dev = hdr->b_l2hdr.b_dev;
+
+ ASSERT(HDR_HAS_L2HDR(hdr));
+ ASSERT((old == hdr_full_cache && new == hdr_l2only_cache) ||
+ (old == hdr_l2only_cache && new == hdr_full_cache));
/*
- * The header isn't being written to the l2arc device, thus it
- * shouldn't have a b_tmp_cdata to free.
+ * if the caller wanted a new full header and the header is to be
+ * encrypted we will actually allocate the header from the full crypt
+ * cache instead. The same applies to freeing from the old cache.
*/
- if (!HDR_L2_WRITING(hdr)) {
- ASSERT3P(hdr->b_l1hdr.b_tmp_cdata, ==, NULL);
- return;
+ if (HDR_PROTECTED(hdr) && new == hdr_full_cache)
+ new = hdr_full_crypt_cache;
+ if (HDR_PROTECTED(hdr) && old == hdr_full_cache)
+ old = hdr_full_crypt_cache;
+
+ nhdr = kmem_cache_alloc(new, KM_PUSHPAGE);
+
+ ASSERT(MUTEX_HELD(HDR_LOCK(hdr)));
+ buf_hash_remove(hdr);
+
+ bcopy(hdr, nhdr, HDR_L2ONLY_SIZE);
+
+ if (new == hdr_full_cache || new == hdr_full_crypt_cache) {
+ arc_hdr_set_flags(nhdr, ARC_FLAG_HAS_L1HDR);
+ /*
+ * arc_access and arc_change_state need to be aware that a
+ * header has just come out of L2ARC, so we set its state to
+ * l2c_only even though it's about to change.
+ */
+ nhdr->b_l1hdr.b_state = arc_l2c_only;
+
+ /* Verify previous threads set to NULL before freeing */
+ ASSERT3P(nhdr->b_l1hdr.b_pabd, ==, NULL);
+ ASSERT(!HDR_HAS_RABD(hdr));
+ } else {
+ ASSERT3P(hdr->b_l1hdr.b_buf, ==, NULL);
+ ASSERT0(hdr->b_l1hdr.b_bufcnt);
+ ASSERT3P(hdr->b_l1hdr.b_freeze_cksum, ==, NULL);
+
+ /*
+ * If we've reached here, We must have been called from
+ * arc_evict_hdr(), as such we should have already been
+ * removed from any ghost list we were previously on
+ * (which protects us from racing with arc_evict_state),
+ * thus no locking is needed during this check.
+ */
+ ASSERT(!multilist_link_active(&hdr->b_l1hdr.b_arc_node));
+
+ /*
+ * A buffer must not be moved into the arc_l2c_only
+ * state if it's not finished being written out to the
+ * l2arc device. Otherwise, the b_l1hdr.b_pabd field
+ * might try to be accessed, even though it was removed.
+ */
+ VERIFY(!HDR_L2_WRITING(hdr));
+ VERIFY3P(hdr->b_l1hdr.b_pabd, ==, NULL);
+ ASSERT(!HDR_HAS_RABD(hdr));
+
+ arc_hdr_clear_flags(nhdr, ARC_FLAG_HAS_L1HDR);
}
+ /*
+ * The header has been reallocated so we need to re-insert it into any
+ * lists it was on.
+ */
+ (void) buf_hash_insert(nhdr, NULL);
+
+ ASSERT(list_link_active(&hdr->b_l2hdr.b_l2node));
+
+ mutex_enter(&dev->l2ad_mtx);
+
+ /*
+ * We must place the realloc'ed header back into the list at
+ * the same spot. Otherwise, if it's placed earlier in the list,
+ * l2arc_write_buffers() could find it during the function's
+ * write phase, and try to write it out to the l2arc.
+ */
+ list_insert_after(&dev->l2ad_buflist, hdr, nhdr);
+ list_remove(&dev->l2ad_buflist, hdr);
+
+ mutex_exit(&dev->l2ad_mtx);
+
+ /*
+ * Since we're using the pointer address as the tag when
+ * incrementing and decrementing the l2ad_alloc refcount, we
+ * must remove the old pointer (that we're about to destroy) and
+ * add the new pointer to the refcount. Otherwise we'd remove
+ * the wrong pointer address when calling arc_hdr_destroy() later.
+ */
+
+ (void) refcount_remove_many(&dev->l2ad_alloc, arc_hdr_size(hdr), hdr);
+ (void) refcount_add_many(&dev->l2ad_alloc, arc_hdr_size(nhdr), nhdr);
+
+ buf_discard_identity(hdr);
+ kmem_cache_free(old, hdr);
+
+ return (nhdr);
+}
+
+/*
+ * This function allows an L1 header to be reallocated as a crypt
+ * header and vice versa. If we are going to a crypt header, the
+ * new fields will be zeroed out.
+ */
+static arc_buf_hdr_t *
+arc_hdr_realloc_crypt(arc_buf_hdr_t *hdr, boolean_t need_crypt)
+{
+ arc_buf_hdr_t *nhdr;
+ arc_buf_t *buf;
+ kmem_cache_t *ncache, *ocache;
+
+ ASSERT(HDR_HAS_L1HDR(hdr));
+ ASSERT3U(!!HDR_PROTECTED(hdr), !=, need_crypt);
+ ASSERT3P(hdr->b_l1hdr.b_state, ==, arc_anon);
+ ASSERT(!multilist_link_active(&hdr->b_l1hdr.b_arc_node));
- /*
- * The header does not have compression enabled. This can be due
- * to the buffer not being compressible, or because we're
- * freeing the buffer before the second phase of
- * l2arc_write_buffer() has started (which does the compression
- * step). In either case, b_tmp_cdata does not point to a
- * separately compressed buffer, so there's nothing to free (it
- * points to the same buffer as the arc_buf_t's b_data field).
- */
- if (HDR_GET_COMPRESS(hdr) == ZIO_COMPRESS_OFF) {
- hdr->b_l1hdr.b_tmp_cdata = NULL;
- return;
+ if (need_crypt) {
+ ncache = hdr_full_crypt_cache;
+ ocache = hdr_full_cache;
+ } else {
+ ncache = hdr_full_cache;
+ ocache = hdr_full_crypt_cache;
}
+ nhdr = kmem_cache_alloc(ncache, KM_PUSHPAGE);
+ bcopy(hdr, nhdr, HDR_L2ONLY_SIZE);
+ nhdr->b_l1hdr.b_freeze_cksum = hdr->b_l1hdr.b_freeze_cksum;
+ nhdr->b_l1hdr.b_bufcnt = hdr->b_l1hdr.b_bufcnt;
+ nhdr->b_l1hdr.b_byteswap = hdr->b_l1hdr.b_byteswap;
+ nhdr->b_l1hdr.b_state = hdr->b_l1hdr.b_state;
+ nhdr->b_l1hdr.b_arc_access = hdr->b_l1hdr.b_arc_access;
+ nhdr->b_l1hdr.b_mru_hits = hdr->b_l1hdr.b_mru_hits;
+ nhdr->b_l1hdr.b_mru_ghost_hits = hdr->b_l1hdr.b_mru_ghost_hits;
+ nhdr->b_l1hdr.b_mfu_hits = hdr->b_l1hdr.b_mfu_hits;
+ nhdr->b_l1hdr.b_mfu_ghost_hits = hdr->b_l1hdr.b_mfu_ghost_hits;
+ nhdr->b_l1hdr.b_l2_hits = hdr->b_l1hdr.b_l2_hits;
+ nhdr->b_l1hdr.b_acb = hdr->b_l1hdr.b_acb;
+ nhdr->b_l1hdr.b_pabd = hdr->b_l1hdr.b_pabd;
+ nhdr->b_l1hdr.b_buf = hdr->b_l1hdr.b_buf;
+
/*
- * There's nothing to free since the buffer was all zero's and
- * compressed to a zero length buffer.
+ * This refcount_add() exists only to ensure that the individual
+ * arc buffers always point to a header that is referenced, avoiding
+ * a small race condition that could trigger ASSERTs.
*/
- if (HDR_GET_COMPRESS(hdr) == ZIO_COMPRESS_EMPTY) {
- ASSERT3P(hdr->b_l1hdr.b_tmp_cdata, ==, NULL);
- return;
+ (void) refcount_add(&nhdr->b_l1hdr.b_refcnt, FTAG);
+
+ for (buf = nhdr->b_l1hdr.b_buf; buf != NULL; buf = buf->b_next) {
+ mutex_enter(&buf->b_evict_lock);
+ buf->b_hdr = nhdr;
+ mutex_exit(&buf->b_evict_lock);
}
- ASSERT(L2ARC_IS_VALID_COMPRESS(HDR_GET_COMPRESS(hdr)));
+ refcount_transfer(&nhdr->b_l1hdr.b_refcnt, &hdr->b_l1hdr.b_refcnt);
+ (void) refcount_remove(&nhdr->b_l1hdr.b_refcnt, FTAG);
+
+ if (need_crypt) {
+ arc_hdr_set_flags(nhdr, ARC_FLAG_PROTECTED);
+ } else {
+ arc_hdr_clear_flags(nhdr, ARC_FLAG_PROTECTED);
+ }
- arc_buf_free_on_write(hdr->b_l1hdr.b_tmp_cdata,
- hdr->b_size, zio_data_buf_free);
+ buf_discard_identity(hdr);
+ kmem_cache_free(ocache, hdr);
- ARCSTAT_BUMP(arcstat_l2_cdata_free_on_write);
- hdr->b_l1hdr.b_tmp_cdata = NULL;
+ return (nhdr);
}
/*
- * Free up buf->b_data and if 'remove' is set, then pull the
- * arc_buf_t off of the the arc_buf_hdr_t's list and free it.
+ * This function is used by the send / receive code to convert a newly
+ * allocated arc_buf_t to one that is suitable for a raw encrypted write. It
+ * is also used to allow the root objset block to be uupdated without altering
+ * its embedded MACs. Both block types will always be uncompressed so we do not
+ * have to worry about compression type or psize.
*/
-static void
-arc_buf_destroy(arc_buf_t *buf, boolean_t remove)
+void
+arc_convert_to_raw(arc_buf_t *buf, uint64_t dsobj, boolean_t byteorder,
+ dmu_object_type_t ot, const uint8_t *salt, const uint8_t *iv,
+ const uint8_t *mac)
{
- arc_buf_t **bufp;
+ arc_buf_hdr_t *hdr = buf->b_hdr;
- /* free up data associated with the buf */
- if (buf->b_data != NULL) {
- arc_state_t *state = buf->b_hdr->b_l1hdr.b_state;
- uint64_t size = buf->b_hdr->b_size;
- arc_buf_contents_t type = arc_buf_type(buf->b_hdr);
+ ASSERT(ot == DMU_OT_DNODE || ot == DMU_OT_OBJSET);
+ ASSERT(HDR_HAS_L1HDR(hdr));
+ ASSERT3P(hdr->b_l1hdr.b_state, ==, arc_anon);
+
+ buf->b_flags |= (ARC_BUF_FLAG_COMPRESSED | ARC_BUF_FLAG_ENCRYPTED);
+ if (!HDR_PROTECTED(hdr))
+ hdr = arc_hdr_realloc_crypt(hdr, B_TRUE);
+ hdr->b_crypt_hdr.b_dsobj = dsobj;
+ hdr->b_crypt_hdr.b_ot = ot;
+ hdr->b_l1hdr.b_byteswap = (byteorder == ZFS_HOST_BYTEORDER) ?
+ DMU_BSWAP_NUMFUNCS : DMU_OT_BYTESWAP(ot);
+ if (!arc_hdr_has_uncompressed_buf(hdr))
+ arc_cksum_free(hdr);
+
+ if (salt != NULL)
+ bcopy(salt, hdr->b_crypt_hdr.b_salt, ZIO_DATA_SALT_LEN);
+ if (iv != NULL)
+ bcopy(iv, hdr->b_crypt_hdr.b_iv, ZIO_DATA_IV_LEN);
+ if (mac != NULL)
+ bcopy(mac, hdr->b_crypt_hdr.b_mac, ZIO_DATA_MAC_LEN);
+}
- arc_cksum_verify(buf);
- arc_buf_unwatch(buf);
+/*
+ * Allocate a new arc_buf_hdr_t and arc_buf_t and return the buf to the caller.
+ * The buf is returned thawed since we expect the consumer to modify it.
+ */
+arc_buf_t *
+arc_alloc_buf(spa_t *spa, void *tag, arc_buf_contents_t type, int32_t size)
+{
+ arc_buf_hdr_t *hdr = arc_hdr_alloc(spa_load_guid(spa), size, size,
+ B_FALSE, ZIO_COMPRESS_OFF, type, B_FALSE);
+ ASSERT(!MUTEX_HELD(HDR_LOCK(hdr)));
- if (type == ARC_BUFC_METADATA) {
- arc_buf_data_free(buf, zio_buf_free);
- arc_space_return(size, ARC_SPACE_META);
- } else {
- ASSERT(type == ARC_BUFC_DATA);
- arc_buf_data_free(buf, zio_data_buf_free);
- arc_space_return(size, ARC_SPACE_DATA);
- }
+ arc_buf_t *buf = NULL;
+ VERIFY0(arc_buf_alloc_impl(hdr, spa, 0, tag, B_FALSE, B_FALSE,
+ B_FALSE, B_FALSE, &buf));
+ arc_buf_thaw(buf);
+
+ return (buf);
+}
- /* protected by hash lock, if in the hash table */
- if (multilist_link_active(&buf->b_hdr->b_l1hdr.b_arc_node)) {
- uint64_t *cnt = &state->arcs_lsize[type];
+/*
+ * Allocate a compressed buf in the same manner as arc_alloc_buf. Don't use this
+ * for bufs containing metadata.
+ */
+arc_buf_t *
+arc_alloc_compressed_buf(spa_t *spa, void *tag, uint64_t psize, uint64_t lsize,
+ enum zio_compress compression_type)
+{
+ ASSERT3U(lsize, >, 0);
+ ASSERT3U(lsize, >=, psize);
+ ASSERT3U(compression_type, >, ZIO_COMPRESS_OFF);
+ ASSERT3U(compression_type, <, ZIO_COMPRESS_FUNCTIONS);
- ASSERT(refcount_is_zero(
- &buf->b_hdr->b_l1hdr.b_refcnt));
- ASSERT(state != arc_anon && state != arc_l2c_only);
+ arc_buf_hdr_t *hdr = arc_hdr_alloc(spa_load_guid(spa), psize, lsize,
+ B_FALSE, compression_type, ARC_BUFC_DATA, B_FALSE);
+ ASSERT(!MUTEX_HELD(HDR_LOCK(hdr)));
- ASSERT3U(*cnt, >=, size);
- atomic_add_64(cnt, -size);
- }
- ASSERT3U(state->arcs_size, >=, size);
- atomic_add_64(&state->arcs_size, -size);
- buf->b_data = NULL;
+ arc_buf_t *buf = NULL;
+ VERIFY0(arc_buf_alloc_impl(hdr, spa, 0, tag, B_FALSE,
+ B_TRUE, B_FALSE, B_FALSE, &buf));
+ arc_buf_thaw(buf);
+ ASSERT3P(hdr->b_l1hdr.b_freeze_cksum, ==, NULL);
+ if (!arc_buf_is_shared(buf)) {
/*
- * If we're destroying a duplicate buffer make sure
- * that the appropriate statistics are updated.
+ * To ensure that the hdr has the correct data in it if we call
+ * arc_untransform() on this buf before it's been written to
+ * disk, it's easiest if we just set up sharing between the
+ * buf and the hdr.
*/
- if (buf->b_hdr->b_l1hdr.b_datacnt > 1 &&
- HDR_ISTYPE_DATA(buf->b_hdr)) {
- ARCSTAT_BUMPDOWN(arcstat_duplicate_buffers);
- ARCSTAT_INCR(arcstat_duplicate_buffers_size, -size);
- }
- ASSERT(buf->b_hdr->b_l1hdr.b_datacnt > 0);
- buf->b_hdr->b_l1hdr.b_datacnt -= 1;
+ ASSERT(!abd_is_linear(hdr->b_l1hdr.b_pabd));
+ arc_hdr_free_abd(hdr, B_FALSE);
+ arc_share_buf(hdr, buf);
}
- /* only remove the buf if requested */
- if (!remove)
- return;
+ return (buf);
+}
- /* remove the buf from the hdr list */
- for (bufp = &buf->b_hdr->b_l1hdr.b_buf; *bufp != buf;
- bufp = &(*bufp)->b_next)
- continue;
- *bufp = buf->b_next;
- buf->b_next = NULL;
+arc_buf_t *
+arc_alloc_raw_buf(spa_t *spa, void *tag, uint64_t dsobj, boolean_t byteorder,
+ const uint8_t *salt, const uint8_t *iv, const uint8_t *mac,
+ dmu_object_type_t ot, uint64_t psize, uint64_t lsize,
+ enum zio_compress compression_type)
+{
+ arc_buf_hdr_t *hdr;
+ arc_buf_t *buf;
+ arc_buf_contents_t type = DMU_OT_IS_METADATA(ot) ?
+ ARC_BUFC_METADATA : ARC_BUFC_DATA;
+
+ ASSERT3U(lsize, >, 0);
+ ASSERT3U(lsize, >=, psize);
+ ASSERT3U(compression_type, >=, ZIO_COMPRESS_OFF);
+ ASSERT3U(compression_type, <, ZIO_COMPRESS_FUNCTIONS);
+
+ hdr = arc_hdr_alloc(spa_load_guid(spa), psize, lsize, B_TRUE,
+ compression_type, type, B_TRUE);
+ ASSERT(!MUTEX_HELD(HDR_LOCK(hdr)));
+
+ hdr->b_crypt_hdr.b_dsobj = dsobj;
+ hdr->b_crypt_hdr.b_ot = ot;
+ hdr->b_l1hdr.b_byteswap = (byteorder == ZFS_HOST_BYTEORDER) ?
+ DMU_BSWAP_NUMFUNCS : DMU_OT_BYTESWAP(ot);
+ bcopy(salt, hdr->b_crypt_hdr.b_salt, ZIO_DATA_SALT_LEN);
+ bcopy(iv, hdr->b_crypt_hdr.b_iv, ZIO_DATA_IV_LEN);
+ bcopy(mac, hdr->b_crypt_hdr.b_mac, ZIO_DATA_MAC_LEN);
- ASSERT(buf->b_efunc == NULL);
+ /*
+ * This buffer will be considered encrypted even if the ot is not an
+ * encrypted type. It will become authenticated instead in
+ * arc_write_ready().
+ */
+ buf = NULL;
+ VERIFY0(arc_buf_alloc_impl(hdr, spa, dsobj, tag, B_TRUE, B_TRUE,
+ B_FALSE, B_FALSE, &buf));
+ arc_buf_thaw(buf);
+ ASSERT3P(hdr->b_l1hdr.b_freeze_cksum, ==, NULL);
- /* clean up the buf */
- buf->b_hdr = NULL;
- kmem_cache_free(buf_cache, buf);
+ return (buf);
+}
+
+static void
+arc_hdr_l2hdr_destroy(arc_buf_hdr_t *hdr)
+{
+ l2arc_buf_hdr_t *l2hdr = &hdr->b_l2hdr;
+ l2arc_dev_t *dev = l2hdr->b_dev;
+ uint64_t psize = arc_hdr_size(hdr);
+
+ ASSERT(MUTEX_HELD(&dev->l2ad_mtx));
+ ASSERT(HDR_HAS_L2HDR(hdr));
+
+ list_remove(&dev->l2ad_buflist, hdr);
+
+ ARCSTAT_INCR(arcstat_l2_psize, -psize);
+ ARCSTAT_INCR(arcstat_l2_lsize, -HDR_GET_LSIZE(hdr));
+
+ vdev_space_update(dev->l2ad_vdev, -psize, 0, 0);
+
+ (void) refcount_remove_many(&dev->l2ad_alloc, psize, hdr);
+ arc_hdr_clear_flags(hdr, ARC_FLAG_HAS_L2HDR);
}
static void
{
if (HDR_HAS_L1HDR(hdr)) {
ASSERT(hdr->b_l1hdr.b_buf == NULL ||
- hdr->b_l1hdr.b_datacnt > 0);
+ hdr->b_l1hdr.b_bufcnt > 0);
ASSERT(refcount_is_zero(&hdr->b_l1hdr.b_refcnt));
ASSERT3P(hdr->b_l1hdr.b_state, ==, arc_anon);
}
ASSERT(!HDR_IO_IN_PROGRESS(hdr));
ASSERT(!HDR_IN_HASH_TABLE(hdr));
- if (HDR_HAS_L2HDR(hdr)) {
- l2arc_buf_hdr_t *l2hdr = &hdr->b_l2hdr;
- boolean_t buflist_held = MUTEX_HELD(&l2hdr->b_dev->l2ad_mtx);
+ if (!HDR_EMPTY(hdr))
+ buf_discard_identity(hdr);
- if (!buflist_held) {
- mutex_enter(&l2hdr->b_dev->l2ad_mtx);
- l2hdr = &hdr->b_l2hdr;
- }
+ if (HDR_HAS_L2HDR(hdr)) {
+ l2arc_dev_t *dev = hdr->b_l2hdr.b_dev;
+ boolean_t buflist_held = MUTEX_HELD(&dev->l2ad_mtx);
- list_remove(&l2hdr->b_dev->l2ad_buflist, hdr);
+ if (!buflist_held)
+ mutex_enter(&dev->l2ad_mtx);
/*
- * We don't want to leak the b_tmp_cdata buffer that was
- * allocated in l2arc_write_buffers()
+ * Even though we checked this conditional above, we
+ * need to check this again now that we have the
+ * l2ad_mtx. This is because we could be racing with
+ * another thread calling l2arc_evict() which might have
+ * destroyed this header's L2 portion as we were waiting
+ * to acquire the l2ad_mtx. If that happens, we don't
+ * want to re-destroy the header's L2 portion.
*/
- arc_buf_l2_cdata_free(hdr);
-
- arc_space_return(HDR_L2ONLY_SIZE, ARC_SPACE_L2HDRS);
- ARCSTAT_INCR(arcstat_l2_size, -hdr->b_size);
- ARCSTAT_INCR(arcstat_l2_asize, -l2hdr->b_asize);
+ if (HDR_HAS_L2HDR(hdr))
+ arc_hdr_l2hdr_destroy(hdr);
if (!buflist_held)
- mutex_exit(&l2hdr->b_dev->l2ad_mtx);
-
- hdr->b_flags &= ~ARC_FLAG_HAS_L2HDR;
+ mutex_exit(&dev->l2ad_mtx);
}
- if (!BUF_EMPTY(hdr))
- buf_discard_identity(hdr);
+ if (HDR_HAS_L1HDR(hdr)) {
+ arc_cksum_free(hdr);
- if (hdr->b_freeze_cksum != NULL) {
- kmem_free(hdr->b_freeze_cksum, sizeof (zio_cksum_t));
- hdr->b_freeze_cksum = NULL;
- }
+ while (hdr->b_l1hdr.b_buf != NULL)
+ arc_buf_destroy_impl(hdr->b_l1hdr.b_buf);
- if (HDR_HAS_L1HDR(hdr)) {
- while (hdr->b_l1hdr.b_buf) {
- arc_buf_t *buf = hdr->b_l1hdr.b_buf;
-
- if (buf->b_efunc != NULL) {
- mutex_enter(&arc_user_evicts_lock);
- mutex_enter(&buf->b_evict_lock);
- ASSERT(buf->b_hdr != NULL);
- arc_buf_destroy(hdr->b_l1hdr.b_buf, FALSE);
- hdr->b_l1hdr.b_buf = buf->b_next;
- buf->b_hdr = &arc_eviction_hdr;
- buf->b_next = arc_eviction_list;
- arc_eviction_list = buf;
- mutex_exit(&buf->b_evict_lock);
- cv_signal(&arc_user_evicts_cv);
- mutex_exit(&arc_user_evicts_lock);
- } else {
- arc_buf_destroy(hdr->b_l1hdr.b_buf, TRUE);
- }
+ if (hdr->b_l1hdr.b_pabd != NULL) {
+ arc_hdr_free_abd(hdr, B_FALSE);
+ }
+
+ if (HDR_HAS_RABD(hdr)) {
+ arc_hdr_free_abd(hdr, B_TRUE);
}
}
if (HDR_HAS_L1HDR(hdr)) {
ASSERT(!multilist_link_active(&hdr->b_l1hdr.b_arc_node));
ASSERT3P(hdr->b_l1hdr.b_acb, ==, NULL);
- kmem_cache_free(hdr_full_cache, hdr);
- } else {
- kmem_cache_free(hdr_l2only_cache, hdr);
- }
-}
-
-void
-arc_buf_free(arc_buf_t *buf, void *tag)
-{
- arc_buf_hdr_t *hdr = buf->b_hdr;
- int hashed = hdr->b_l1hdr.b_state != arc_anon;
-
- ASSERT(buf->b_efunc == NULL);
- ASSERT(buf->b_data != NULL);
-
- if (hashed) {
- kmutex_t *hash_lock = HDR_LOCK(hdr);
-
- mutex_enter(hash_lock);
- hdr = buf->b_hdr;
- ASSERT3P(hash_lock, ==, HDR_LOCK(hdr));
- (void) remove_reference(hdr, hash_lock, tag);
- if (hdr->b_l1hdr.b_datacnt > 1) {
- arc_buf_destroy(buf, TRUE);
+ if (!HDR_PROTECTED(hdr)) {
+ kmem_cache_free(hdr_full_cache, hdr);
} else {
- ASSERT(buf == hdr->b_l1hdr.b_buf);
- ASSERT(buf->b_efunc == NULL);
- hdr->b_flags |= ARC_FLAG_BUF_AVAILABLE;
+ kmem_cache_free(hdr_full_crypt_cache, hdr);
}
- mutex_exit(hash_lock);
- } else if (HDR_IO_IN_PROGRESS(hdr)) {
- int destroy_hdr;
- /*
- * We are in the middle of an async write. Don't destroy
- * this buffer unless the write completes before we finish
- * decrementing the reference count.
- */
- mutex_enter(&arc_user_evicts_lock);
- (void) remove_reference(hdr, NULL, tag);
- ASSERT(refcount_is_zero(&hdr->b_l1hdr.b_refcnt));
- destroy_hdr = !HDR_IO_IN_PROGRESS(hdr);
- mutex_exit(&arc_user_evicts_lock);
- if (destroy_hdr)
- arc_hdr_destroy(hdr);
} else {
- if (remove_reference(hdr, NULL, tag) > 0)
- arc_buf_destroy(buf, TRUE);
- else
- arc_hdr_destroy(hdr);
+ kmem_cache_free(hdr_l2only_cache, hdr);
}
}
-boolean_t
-arc_buf_remove_ref(arc_buf_t *buf, void* tag)
+void
+arc_buf_destroy(arc_buf_t *buf, void* tag)
{
arc_buf_hdr_t *hdr = buf->b_hdr;
- kmutex_t *hash_lock = NULL;
- boolean_t no_callback = (buf->b_efunc == NULL);
+ kmutex_t *hash_lock = HDR_LOCK(hdr);
if (hdr->b_l1hdr.b_state == arc_anon) {
- ASSERT(hdr->b_l1hdr.b_datacnt == 1);
- arc_buf_free(buf, tag);
- return (no_callback);
+ ASSERT3U(hdr->b_l1hdr.b_bufcnt, ==, 1);
+ ASSERT(!HDR_IO_IN_PROGRESS(hdr));
+ VERIFY0(remove_reference(hdr, NULL, tag));
+ arc_hdr_destroy(hdr);
+ return;
}
- hash_lock = HDR_LOCK(hdr);
mutex_enter(hash_lock);
- hdr = buf->b_hdr;
- ASSERT(hdr->b_l1hdr.b_datacnt > 0);
+ ASSERT3P(hdr, ==, buf->b_hdr);
+ ASSERT(hdr->b_l1hdr.b_bufcnt > 0);
ASSERT3P(hash_lock, ==, HDR_LOCK(hdr));
- ASSERT(hdr->b_l1hdr.b_state != arc_anon);
- ASSERT(buf->b_data != NULL);
+ ASSERT3P(hdr->b_l1hdr.b_state, !=, arc_anon);
+ ASSERT3P(buf->b_data, !=, NULL);
(void) remove_reference(hdr, hash_lock, tag);
- if (hdr->b_l1hdr.b_datacnt > 1) {
- if (no_callback)
- arc_buf_destroy(buf, TRUE);
- } else if (no_callback) {
- ASSERT(hdr->b_l1hdr.b_buf == buf && buf->b_next == NULL);
- ASSERT(buf->b_efunc == NULL);
- hdr->b_flags |= ARC_FLAG_BUF_AVAILABLE;
- }
- ASSERT(no_callback || hdr->b_l1hdr.b_datacnt > 1 ||
- refcount_is_zero(&hdr->b_l1hdr.b_refcnt));
+ arc_buf_destroy_impl(buf);
mutex_exit(hash_lock);
- return (no_callback);
-}
-
-uint64_t
-arc_buf_size(arc_buf_t *buf)
-{
- return (buf->b_hdr->b_size);
-}
-
-/*
- * Called from the DMU to determine if the current buffer should be
- * evicted. In order to ensure proper locking, the eviction must be initiated
- * from the DMU. Return true if the buffer is associated with user data and
- * duplicate buffers still exist.
- */
-boolean_t
-arc_buf_eviction_needed(arc_buf_t *buf)
-{
- arc_buf_hdr_t *hdr;
- boolean_t evict_needed = B_FALSE;
-
- if (zfs_disable_dup_eviction)
- return (B_FALSE);
-
- mutex_enter(&buf->b_evict_lock);
- hdr = buf->b_hdr;
- if (hdr == NULL) {
- /*
- * We are in arc_do_user_evicts(); let that function
- * perform the eviction.
- */
- ASSERT(buf->b_data == NULL);
- mutex_exit(&buf->b_evict_lock);
- return (B_FALSE);
- } else if (buf->b_data == NULL) {
- /*
- * We have already been added to the arc eviction list;
- * recommend eviction.
- */
- ASSERT3P(hdr, ==, &arc_eviction_hdr);
- mutex_exit(&buf->b_evict_lock);
- return (B_TRUE);
- }
-
- if (hdr->b_l1hdr.b_datacnt > 1 && HDR_ISTYPE_DATA(hdr))
- evict_needed = B_TRUE;
-
- mutex_exit(&buf->b_evict_lock);
- return (evict_needed);
}
/*
state = hdr->b_l1hdr.b_state;
if (GHOST_STATE(state)) {
ASSERT(!HDR_IO_IN_PROGRESS(hdr));
- ASSERT(hdr->b_l1hdr.b_buf == NULL);
+ ASSERT3P(hdr->b_l1hdr.b_buf, ==, NULL);
/*
* l2arc_write_buffers() relies on a header's L1 portion
- * (i.e. its b_tmp_cdata field) during its write phase.
+ * (i.e. its b_pabd field) during it's write phase.
* Thus, we cannot push a header onto the arc_l2c_only
* state (removing its L1 piece) until the header is
* done being written to the l2arc.
}
ARCSTAT_BUMP(arcstat_deleted);
- bytes_evicted += hdr->b_size;
+ bytes_evicted += HDR_GET_LSIZE(hdr);
DTRACE_PROBE1(arc__delete, arc_buf_hdr_t *, hdr);
if (HDR_HAS_L2HDR(hdr)) {
+ ASSERT(hdr->b_l1hdr.b_pabd == NULL);
+ ASSERT(!HDR_HAS_RABD(hdr));
/*
* This buffer is cached on the 2nd Level ARC;
* don't destroy the header.
}
ASSERT0(refcount_count(&hdr->b_l1hdr.b_refcnt));
- ASSERT3U(hdr->b_l1hdr.b_datacnt, >, 0);
while (hdr->b_l1hdr.b_buf) {
arc_buf_t *buf = hdr->b_l1hdr.b_buf;
if (!mutex_tryenter(&buf->b_evict_lock)) {
break;
}
if (buf->b_data != NULL)
- bytes_evicted += hdr->b_size;
- if (buf->b_efunc != NULL) {
- mutex_enter(&arc_user_evicts_lock);
- arc_buf_destroy(buf, FALSE);
- hdr->b_l1hdr.b_buf = buf->b_next;
- buf->b_hdr = &arc_eviction_hdr;
- buf->b_next = arc_eviction_list;
- arc_eviction_list = buf;
- cv_signal(&arc_user_evicts_cv);
- mutex_exit(&arc_user_evicts_lock);
- mutex_exit(&buf->b_evict_lock);
- } else {
- mutex_exit(&buf->b_evict_lock);
- arc_buf_destroy(buf, TRUE);
- }
+ bytes_evicted += HDR_GET_LSIZE(hdr);
+ mutex_exit(&buf->b_evict_lock);
+ arc_buf_destroy_impl(buf);
}
if (HDR_HAS_L2HDR(hdr)) {
- ARCSTAT_INCR(arcstat_evict_l2_cached, hdr->b_size);
+ ARCSTAT_INCR(arcstat_evict_l2_cached, HDR_GET_LSIZE(hdr));
} else {
- if (l2arc_write_eligible(hdr->b_spa, hdr))
- ARCSTAT_INCR(arcstat_evict_l2_eligible, hdr->b_size);
- else
- ARCSTAT_INCR(arcstat_evict_l2_ineligible, hdr->b_size);
+ if (l2arc_write_eligible(hdr->b_spa, hdr)) {
+ ARCSTAT_INCR(arcstat_evict_l2_eligible,
+ HDR_GET_LSIZE(hdr));
+ } else {
+ ARCSTAT_INCR(arcstat_evict_l2_ineligible,
+ HDR_GET_LSIZE(hdr));
+ }
}
- if (hdr->b_l1hdr.b_datacnt == 0) {
+ if (hdr->b_l1hdr.b_bufcnt == 0) {
+ arc_cksum_free(hdr);
+
+ bytes_evicted += arc_hdr_size(hdr);
+
+ /*
+ * If this hdr is being evicted and has a compressed
+ * buffer then we discard it here before we change states.
+ * This ensures that the accounting is updated correctly
+ * in arc_free_data_impl().
+ */
+ if (hdr->b_l1hdr.b_pabd != NULL)
+ arc_hdr_free_abd(hdr, B_FALSE);
+
+ if (HDR_HAS_RABD(hdr))
+ arc_hdr_free_abd(hdr, B_TRUE);
+
arc_change_state(evicted_state, hdr, hash_lock);
ASSERT(HDR_IN_HASH_TABLE(hdr));
- hdr->b_flags |= ARC_FLAG_IN_HASH_TABLE;
- hdr->b_flags &= ~ARC_FLAG_BUF_AVAILABLE;
+ arc_hdr_set_flags(hdr, ARC_FLAG_IN_HASH_TABLE);
DTRACE_PROBE1(arc__evict, arc_buf_hdr_t *, hdr);
}
int evict_count = 0;
ASSERT3P(marker, !=, NULL);
- ASSERTV(if (bytes < 0) ASSERT(bytes == ARC_EVICT_ALL));
+ IMPLY(bytes < 0, bytes == ARC_EVICT_ALL);
mls = multilist_sublist_lock(ml, idx);
* thread. If we used cv_broadcast, we could
* wake up "too many" threads causing arc_size
* to significantly overflow arc_c; since
- * arc_get_data_buf() doesn't check for overflow
+ * arc_get_data_impl() doesn't check for overflow
* when it's woken up (it doesn't because it's
* possible for the ARC to be overflowing while
* full of un-evictable buffers, and the
arc_buf_contents_t type)
{
uint64_t total_evicted = 0;
- multilist_t *ml = &state->arcs_list[type];
+ multilist_t *ml = state->arcs_list[type];
int num_sublists;
arc_buf_hdr_t **markers;
int i;
- ASSERTV(if (bytes < 0) ASSERT(bytes == ARC_EVICT_ALL));
+ IMPLY(bytes < 0, bytes == ARC_EVICT_ALL);
num_sublists = multilist_get_num_sublists(ml);
* we're evicting all available buffers.
*/
while (total_evicted < bytes || bytes == ARC_EVICT_ALL) {
+ int sublist_idx = multilist_get_random_index(ml);
+ uint64_t scan_evicted = 0;
+
+ /*
+ * Try to reduce pinned dnodes with a floor of arc_dnode_limit.
+ * Request that 10% of the LRUs be scanned by the superblock
+ * shrinker.
+ */
+ if (type == ARC_BUFC_DATA && arc_dnode_size > arc_dnode_limit)
+ arc_prune_async((arc_dnode_size - arc_dnode_limit) /
+ sizeof (dnode_t) / zfs_arc_dnode_reduce_percent);
+
/*
* Start eviction using a randomly selected sublist,
* this is to try and evenly balance eviction across all
* (e.g. index 0) would cause evictions to favor certain
* sublists over others.
*/
- int sublist_idx = multilist_get_random_index(ml);
- uint64_t scan_evicted = 0;
-
for (i = 0; i < num_sublists; i++) {
uint64_t bytes_remaining;
uint64_t bytes_evicted;
* Flush all "evictable" data of the given type from the arc state
* specified. This will not evict any "active" buffers (i.e. referenced).
*
- * When 'retry' is set to FALSE, the function will make a single pass
+ * When 'retry' is set to B_FALSE, the function will make a single pass
* over the state and evict any buffers that it can. Since it doesn't
* continually retry the eviction, it might end up leaving some buffers
* in the ARC due to lock misses.
*
- * When 'retry' is set to TRUE, the function will continually retry the
+ * When 'retry' is set to B_TRUE, the function will continually retry the
* eviction until *all* evictable buffers have been removed from the
* state. As a result, if concurrent insertions into the state are
* allowed (e.g. if the ARC isn't shutting down), this function might
{
uint64_t evicted = 0;
- while (state->arcs_lsize[type] != 0) {
+ while (refcount_count(&state->arcs_esize[type]) != 0) {
evicted += arc_evict_state(state, spa, ARC_EVICT_ALL, type);
if (!retry)
}
/*
- * Helper function for arc_prune() it is responsible for safely handling
- * the execution of a registered arc_prune_func_t.
+ * Helper function for arc_prune_async() it is responsible for safely
+ * handling the execution of a registered arc_prune_func_t.
*/
static void
arc_prune_task(void *ptr)
if (func != NULL)
func(ap->p_adjust, ap->p_private);
- /* Callback unregistered concurrently with execution */
- if (refcount_remove(&ap->p_refcnt, func) == 0) {
- ASSERT(!list_link_active(&ap->p_node));
- refcount_destroy(&ap->p_refcnt);
- kmem_free(ap, sizeof (*ap));
- }
+ refcount_remove(&ap->p_refcnt, func);
}
/*
* honor the arc_meta_limit and reclaim otherwise pinned ARC buffers. This
* is analogous to dnlc_reduce_cache() but more generic.
*
- * This operation is performed asyncronously so it may be safely called
- * in the context of the arc_adapt_thread(). A reference is taken here
+ * This operation is performed asynchronously so it may be safely called
+ * in the context of the arc_reclaim_thread(). A reference is taken here
* for each registered arc_prune_t and the arc_prune_task() is responsible
* for releasing it once the registered arc_prune_func_t has completed.
*/
refcount_add(&ap->p_refcnt, ap->p_pfunc);
ap->p_adjust = adjust;
- taskq_dispatch(arc_prune_taskq, arc_prune_task, ap, TQ_SLEEP);
+ if (taskq_dispatch(arc_prune_taskq, arc_prune_task,
+ ap, TQ_SLEEP) == TASKQID_INVALID) {
+ refcount_remove(&ap->p_refcnt, ap->p_pfunc);
+ continue;
+ }
ARCSTAT_BUMP(arcstat_prune);
}
mutex_exit(&arc_prune_mtx);
}
-static void
-arc_prune(int64_t adjust)
-{
- arc_prune_async(adjust);
- taskq_wait_outstanding(arc_prune_taskq, 0);
-}
-
/*
* Evict the specified number of bytes from the state specified,
* restricting eviction to the spa and type given. This function
{
int64_t delta;
- if (bytes > 0 && state->arcs_lsize[type] > 0) {
- delta = MIN(state->arcs_lsize[type], bytes);
+ if (bytes > 0 && refcount_count(&state->arcs_esize[type]) > 0) {
+ delta = MIN(refcount_count(&state->arcs_esize[type]), bytes);
return (arc_evict_state(state, spa, delta, type));
}
static uint64_t
arc_adjust_meta_balanced(void)
{
- int64_t adjustmnt, delta, prune = 0;
+ int64_t delta, prune = 0, adjustmnt;
uint64_t total_evicted = 0;
arc_buf_contents_t type = ARC_BUFC_DATA;
- unsigned long restarts = zfs_arc_meta_adjust_restarts;
+ int restarts = MAX(zfs_arc_meta_adjust_restarts, 0);
restart:
/*
*/
adjustmnt = arc_meta_used - arc_meta_limit;
- if (adjustmnt > 0 && arc_mru->arcs_lsize[type] > 0) {
- delta = MIN(arc_mru->arcs_lsize[type], adjustmnt);
+ if (adjustmnt > 0 && refcount_count(&arc_mru->arcs_esize[type]) > 0) {
+ delta = MIN(refcount_count(&arc_mru->arcs_esize[type]),
+ adjustmnt);
total_evicted += arc_adjust_impl(arc_mru, 0, delta, type);
adjustmnt -= delta;
}
* simply decrement the amount of data evicted from the MRU.
*/
- if (adjustmnt > 0 && arc_mfu->arcs_lsize[type] > 0) {
- delta = MIN(arc_mfu->arcs_lsize[type], adjustmnt);
+ if (adjustmnt > 0 && refcount_count(&arc_mfu->arcs_esize[type]) > 0) {
+ delta = MIN(refcount_count(&arc_mfu->arcs_esize[type]),
+ adjustmnt);
total_evicted += arc_adjust_impl(arc_mfu, 0, delta, type);
}
adjustmnt = arc_meta_used - arc_meta_limit;
- if (adjustmnt > 0 && arc_mru_ghost->arcs_lsize[type] > 0) {
+ if (adjustmnt > 0 &&
+ refcount_count(&arc_mru_ghost->arcs_esize[type]) > 0) {
delta = MIN(adjustmnt,
- arc_mru_ghost->arcs_lsize[type]);
+ refcount_count(&arc_mru_ghost->arcs_esize[type]));
total_evicted += arc_adjust_impl(arc_mru_ghost, 0, delta, type);
adjustmnt -= delta;
}
- if (adjustmnt > 0 && arc_mfu_ghost->arcs_lsize[type] > 0) {
+ if (adjustmnt > 0 &&
+ refcount_count(&arc_mfu_ghost->arcs_esize[type]) > 0) {
delta = MIN(adjustmnt,
- arc_mfu_ghost->arcs_lsize[type]);
+ refcount_count(&arc_mfu_ghost->arcs_esize[type]));
total_evicted += arc_adjust_impl(arc_mfu_ghost, 0, delta, type);
}
* evict some from the MRU here, and some from the MFU below.
*/
target = MIN((int64_t)(arc_meta_used - arc_meta_limit),
- (int64_t)(arc_anon->arcs_size + arc_mru->arcs_size - arc_p));
+ (int64_t)(refcount_count(&arc_anon->arcs_size) +
+ refcount_count(&arc_mru->arcs_size) - arc_p));
total_evicted += arc_adjust_impl(arc_mru, 0, target, ARC_BUFC_METADATA);
/*
* Similar to the above, we want to evict enough bytes to get us
* below the meta limit, but not so much as to drop us below the
- * space alloted to the MFU (which is defined as arc_c - arc_p).
+ * space allotted to the MFU (which is defined as arc_c - arc_p).
*/
target = MIN((int64_t)(arc_meta_used - arc_meta_limit),
- (int64_t)(arc_mfu->arcs_size - (arc_c - arc_p)));
+ (int64_t)(refcount_count(&arc_mfu->arcs_size) - (arc_c - arc_p)));
total_evicted += arc_adjust_impl(arc_mfu, 0, target, ARC_BUFC_METADATA);
static arc_buf_contents_t
arc_adjust_type(arc_state_t *state)
{
- multilist_t *data_ml = &state->arcs_list[ARC_BUFC_DATA];
- multilist_t *meta_ml = &state->arcs_list[ARC_BUFC_METADATA];
+ multilist_t *data_ml = state->arcs_list[ARC_BUFC_DATA];
+ multilist_t *meta_ml = state->arcs_list[ARC_BUFC_METADATA];
int data_idx = multilist_get_random_index(data_ml);
int meta_idx = multilist_get_random_index(meta_ml);
multilist_sublist_t *data_mls;
* arc_p here, and then evict more from the MFU below.
*/
target = MIN((int64_t)(arc_size - arc_c),
- (int64_t)(arc_anon->arcs_size + arc_mru->arcs_size + arc_meta_used -
- arc_p));
+ (int64_t)(refcount_count(&arc_anon->arcs_size) +
+ refcount_count(&arc_mru->arcs_size) + arc_meta_used - arc_p));
/*
* If we're below arc_meta_min, always prefer to evict data.
*/
target = arc_size - arc_c;
- if (arc_adjust_type(arc_mru) == ARC_BUFC_METADATA &&
+ if (arc_adjust_type(arc_mfu) == ARC_BUFC_METADATA &&
arc_meta_used > arc_meta_min) {
bytes = arc_adjust_impl(arc_mfu, 0, target, ARC_BUFC_METADATA);
total_evicted += bytes;
* cache. The following logic enforces these limits on the ghost
* caches, and evicts from them as needed.
*/
- target = arc_mru->arcs_size + arc_mru_ghost->arcs_size - arc_c;
+ target = refcount_count(&arc_mru->arcs_size) +
+ refcount_count(&arc_mru_ghost->arcs_size) - arc_c;
bytes = arc_adjust_impl(arc_mru_ghost, 0, target, ARC_BUFC_DATA);
total_evicted += bytes;
* mru + mfu + mru ghost + mfu ghost <= 2 * arc_c
* mru ghost + mfu ghost <= arc_c
*/
- target = arc_mru_ghost->arcs_size + arc_mfu_ghost->arcs_size - arc_c;
+ target = refcount_count(&arc_mru_ghost->arcs_size) +
+ refcount_count(&arc_mfu_ghost->arcs_size) - arc_c;
bytes = arc_adjust_impl(arc_mfu_ghost, 0, target, ARC_BUFC_DATA);
total_evicted += bytes;
return (total_evicted);
}
-static void
-arc_do_user_evicts(void)
-{
- mutex_enter(&arc_user_evicts_lock);
- while (arc_eviction_list != NULL) {
- arc_buf_t *buf = arc_eviction_list;
- arc_eviction_list = buf->b_next;
- mutex_enter(&buf->b_evict_lock);
- buf->b_hdr = NULL;
- mutex_exit(&buf->b_evict_lock);
- mutex_exit(&arc_user_evicts_lock);
-
- if (buf->b_efunc != NULL)
- VERIFY0(buf->b_efunc(buf->b_private));
-
- buf->b_efunc = NULL;
- buf->b_private = NULL;
- kmem_cache_free(buf_cache, buf);
- mutex_enter(&arc_user_evicts_lock);
- }
- mutex_exit(&arc_user_evicts_lock);
-}
-
void
arc_flush(spa_t *spa, boolean_t retry)
{
uint64_t guid = 0;
/*
- * If retry is TRUE, a spa must not be specified since we have
+ * If retry is B_TRUE, a spa must not be specified since we have
* no good way to determine if all of a spa's buffers have been
* evicted from an arc state.
*/
(void) arc_flush_state(arc_mfu_ghost, guid, ARC_BUFC_DATA, retry);
(void) arc_flush_state(arc_mfu_ghost, guid, ARC_BUFC_METADATA, retry);
-
- arc_do_user_evicts();
- ASSERT(spa || arc_eviction_list == NULL);
}
void
-arc_shrink(uint64_t bytes)
+arc_shrink(int64_t to_free)
{
- if (arc_c > arc_c_min) {
- uint64_t to_free;
+ uint64_t c = arc_c;
+
+ if (c > to_free && c - to_free > arc_c_min) {
+ arc_c = c - to_free;
+ atomic_add_64(&arc_p, -(arc_p >> arc_shrink_shift));
+ if (arc_c > arc_size)
+ arc_c = MAX(arc_size, arc_c_min);
+ if (arc_p > arc_c)
+ arc_p = (arc_c >> 1);
+ ASSERT(arc_c >= arc_c_min);
+ ASSERT((int64_t)arc_p >= 0);
+ } else {
+ arc_c = arc_c_min;
+ }
- to_free = bytes ? bytes : arc_c >> zfs_arc_shrink_shift;
+ if (arc_size > arc_c)
+ (void) arc_adjust();
+}
- if (arc_c > arc_c_min + to_free)
- atomic_add_64(&arc_c, -to_free);
- else
- arc_c = arc_c_min;
+/*
+ * Return maximum amount of memory that we could possibly use. Reduced
+ * to half of all memory in user space which is primarily used for testing.
+ */
+static uint64_t
+arc_all_memory(void)
+{
+#ifdef _KERNEL
+#ifdef CONFIG_HIGHMEM
+ return (ptob(totalram_pages - totalhigh_pages));
+#else
+ return (ptob(totalram_pages));
+#endif /* CONFIG_HIGHMEM */
+#else
+ return (ptob(physmem) / 2);
+#endif /* _KERNEL */
+}
+
+/*
+ * Return the amount of memory that is considered free. In user space
+ * which is primarily used for testing we pretend that free memory ranges
+ * from 0-20% of all memory.
+ */
+static uint64_t
+arc_free_memory(void)
+{
+#ifdef _KERNEL
+#ifdef CONFIG_HIGHMEM
+ struct sysinfo si;
+ si_meminfo(&si);
+ return (ptob(si.freeram - si.freehigh));
+#else
+#ifdef ZFS_GLOBAL_NODE_PAGE_STATE
+ return (ptob(nr_free_pages() +
+ global_node_page_state(NR_INACTIVE_FILE) +
+ global_node_page_state(NR_INACTIVE_ANON) +
+ global_node_page_state(NR_SLAB_RECLAIMABLE)));
+#else
+ return (ptob(nr_free_pages() +
+ global_page_state(NR_INACTIVE_FILE) +
+ global_page_state(NR_INACTIVE_ANON) +
+ global_page_state(NR_SLAB_RECLAIMABLE)));
+#endif /* ZFS_GLOBAL_NODE_PAGE_STATE */
+#endif /* CONFIG_HIGHMEM */
+#else
+ return (spa_get_random(arc_all_memory() * 20 / 100));
+#endif /* _KERNEL */
+}
+
+typedef enum free_memory_reason_t {
+ FMR_UNKNOWN,
+ FMR_NEEDFREE,
+ FMR_LOTSFREE,
+ FMR_SWAPFS_MINFREE,
+ FMR_PAGES_PP_MAXIMUM,
+ FMR_HEAP_ARENA,
+ FMR_ZIO_ARENA,
+} free_memory_reason_t;
+
+int64_t last_free_memory;
+free_memory_reason_t last_free_reason;
+
+#ifdef _KERNEL
+/*
+ * Additional reserve of pages for pp_reserve.
+ */
+int64_t arc_pages_pp_reserve = 64;
+
+/*
+ * Additional reserve of pages for swapfs.
+ */
+int64_t arc_swapfs_reserve = 64;
+#endif /* _KERNEL */
+
+/*
+ * Return the amount of memory that can be consumed before reclaim will be
+ * needed. Positive if there is sufficient free memory, negative indicates
+ * the amount of memory that needs to be freed up.
+ */
+static int64_t
+arc_available_memory(void)
+{
+ int64_t lowest = INT64_MAX;
+ free_memory_reason_t r = FMR_UNKNOWN;
+#ifdef _KERNEL
+ int64_t n;
+#ifdef __linux__
+#ifdef freemem
+#undef freemem
+#endif
+ pgcnt_t needfree = btop(arc_need_free);
+ pgcnt_t lotsfree = btop(arc_sys_free);
+ pgcnt_t desfree = 0;
+ pgcnt_t freemem = btop(arc_free_memory());
+#endif
+
+ if (needfree > 0) {
+ n = PAGESIZE * (-needfree);
+ if (n < lowest) {
+ lowest = n;
+ r = FMR_NEEDFREE;
+ }
+ }
+
+ /*
+ * check that we're out of range of the pageout scanner. It starts to
+ * schedule paging if freemem is less than lotsfree and needfree.
+ * lotsfree is the high-water mark for pageout, and needfree is the
+ * number of needed free pages. We add extra pages here to make sure
+ * the scanner doesn't start up while we're freeing memory.
+ */
+ n = PAGESIZE * (freemem - lotsfree - needfree - desfree);
+ if (n < lowest) {
+ lowest = n;
+ r = FMR_LOTSFREE;
+ }
+
+#ifndef __linux__
+ /*
+ * check to make sure that swapfs has enough space so that anon
+ * reservations can still succeed. anon_resvmem() checks that the
+ * availrmem is greater than swapfs_minfree, and the number of reserved
+ * swap pages. We also add a bit of extra here just to prevent
+ * circumstances from getting really dire.
+ */
+ n = PAGESIZE * (availrmem - swapfs_minfree - swapfs_reserve -
+ desfree - arc_swapfs_reserve);
+ if (n < lowest) {
+ lowest = n;
+ r = FMR_SWAPFS_MINFREE;
+ }
+
+ /*
+ * Check that we have enough availrmem that memory locking (e.g., via
+ * mlock(3C) or memcntl(2)) can still succeed. (pages_pp_maximum
+ * stores the number of pages that cannot be locked; when availrmem
+ * drops below pages_pp_maximum, page locking mechanisms such as
+ * page_pp_lock() will fail.)
+ */
+ n = PAGESIZE * (availrmem - pages_pp_maximum -
+ arc_pages_pp_reserve);
+ if (n < lowest) {
+ lowest = n;
+ r = FMR_PAGES_PP_MAXIMUM;
+ }
+#endif
+
+#if defined(_ILP32)
+ /*
+ * If we're on a 32-bit platform, it's possible that we'll exhaust the
+ * kernel heap space before we ever run out of available physical
+ * memory. Most checks of the size of the heap_area compare against
+ * tune.t_minarmem, which is the minimum available real memory that we
+ * can have in the system. However, this is generally fixed at 25 pages
+ * which is so low that it's useless. In this comparison, we seek to
+ * calculate the total heap-size, and reclaim if more than 3/4ths of the
+ * heap is allocated. (Or, in the calculation, if less than 1/4th is
+ * free)
+ */
+ n = vmem_size(heap_arena, VMEM_FREE) -
+ (vmem_size(heap_arena, VMEM_FREE | VMEM_ALLOC) >> 2);
+ if (n < lowest) {
+ lowest = n;
+ r = FMR_HEAP_ARENA;
+ }
+#endif
- to_free = bytes ? bytes : arc_p >> zfs_arc_shrink_shift;
+ /*
+ * If zio data pages are being allocated out of a separate heap segment,
+ * then enforce that the size of available vmem for this arena remains
+ * above about 1/4th (1/(2^arc_zio_arena_free_shift)) free.
+ *
+ * Note that reducing the arc_zio_arena_free_shift keeps more virtual
+ * memory (in the zio_arena) free, which can avoid memory
+ * fragmentation issues.
+ */
+ if (zio_arena != NULL) {
+ n = (int64_t)vmem_size(zio_arena, VMEM_FREE) -
+ (vmem_size(zio_arena, VMEM_ALLOC) >>
+ arc_zio_arena_free_shift);
+ if (n < lowest) {
+ lowest = n;
+ r = FMR_ZIO_ARENA;
+ }
+ }
+#else /* _KERNEL */
+ /* Every 100 calls, free a small amount */
+ if (spa_get_random(100) == 0)
+ lowest = -1024;
+#endif /* _KERNEL */
- if (arc_p > to_free)
- atomic_add_64(&arc_p, -to_free);
- else
- arc_p = 0;
+ last_free_memory = lowest;
+ last_free_reason = r;
- if (arc_c > arc_size)
- arc_c = MAX(arc_size, arc_c_min);
- if (arc_p > arc_c)
- arc_p = (arc_c >> 1);
- ASSERT(arc_c >= arc_c_min);
- ASSERT((int64_t)arc_p >= 0);
- }
+ return (lowest);
+}
- if (arc_size > arc_c)
- (void) arc_adjust();
+/*
+ * Determine if the system is under memory pressure and is asking
+ * to reclaim memory. A return value of B_TRUE indicates that the system
+ * is under memory pressure and that the arc should adjust accordingly.
+ */
+static boolean_t
+arc_reclaim_needed(void)
+{
+ return (arc_available_memory() < 0);
}
static void
-arc_kmem_reap_now(arc_reclaim_strategy_t strat, uint64_t bytes)
+arc_kmem_reap_now(void)
{
size_t i;
kmem_cache_t *prev_cache = NULL;
kmem_cache_t *prev_data_cache = NULL;
extern kmem_cache_t *zio_buf_cache[];
extern kmem_cache_t *zio_data_buf_cache[];
+ extern kmem_cache_t *range_seg_cache;
+#ifdef _KERNEL
if ((arc_meta_used >= arc_meta_limit) && zfs_arc_meta_prune) {
/*
* We are exceeding our meta-data cache limit.
* Prune some entries to release holds on meta-data.
*/
- arc_prune(zfs_arc_meta_prune);
+ arc_prune_async(zfs_arc_meta_prune);
}
-
+#if defined(_ILP32)
/*
- * An aggressive reclamation will shrink the cache size as well as
- * reap free buffers from the arc kmem caches.
+ * Reclaim unused memory from all kmem caches.
*/
- if (strat == ARC_RECLAIM_AGGR)
- arc_shrink(bytes);
+ kmem_reap();
+#endif
+#endif
for (i = 0; i < SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT; i++) {
+#if defined(_ILP32)
+ /* reach upper limit of cache size on 32-bit */
+ if (zio_buf_cache[i] == NULL)
+ break;
+#endif
if (zio_buf_cache[i] != prev_cache) {
prev_cache = zio_buf_cache[i];
kmem_cache_reap_now(zio_buf_cache[i]);
kmem_cache_reap_now(zio_data_buf_cache[i]);
}
}
-
kmem_cache_reap_now(buf_cache);
kmem_cache_reap_now(hdr_full_cache);
kmem_cache_reap_now(hdr_l2only_cache);
+ kmem_cache_reap_now(range_seg_cache);
+
+ if (zio_arena != NULL) {
+ /*
+ * Ask the vmem arena to reclaim unused memory from its
+ * quantum caches.
+ */
+ vmem_qcache_reap(zio_arena);
+ }
}
/*
- * Threads can block in arc_get_data_buf() waiting for this thread to evict
+ * Threads can block in arc_get_data_impl() waiting for this thread to evict
* enough data and signal them to proceed. When this happens, the threads in
- * arc_get_data_buf() are sleeping while holding the hash lock for their
+ * arc_get_data_impl() are sleeping while holding the hash lock for their
* particular arc header. Thus, we must be careful to never sleep on a
* hash lock in this thread. This is to prevent the following deadlock:
*
- * - Thread A sleeps on CV in arc_get_data_buf() holding hash lock "L",
+ * - Thread A sleeps on CV in arc_get_data_impl() holding hash lock "L",
* waiting for the reclaim thread to signal it.
*
* - arc_reclaim_thread() tries to acquire hash lock "L" using mutex_enter,
* using mutex_tryenter() from arc_reclaim_thread().
*/
static void
-arc_adapt_thread(void)
+arc_reclaim_thread(void *unused)
{
+ fstrans_cookie_t cookie = spl_fstrans_mark();
+ hrtime_t growtime = 0;
callb_cpr_t cpr;
- fstrans_cookie_t cookie;
- uint64_t arc_evicted;
CALLB_CPR_INIT(&cpr, &arc_reclaim_lock, callb_generic_cpr, FTAG);
- cookie = spl_fstrans_mark();
mutex_enter(&arc_reclaim_lock);
- while (arc_reclaim_thread_exit == 0) {
-#ifndef _KERNEL
- arc_reclaim_strategy_t last_reclaim = ARC_RECLAIM_CONS;
-
- mutex_exit(&arc_reclaim_lock);
- if (spa_get_random(100) == 0) {
-
- if (arc_no_grow) {
- if (last_reclaim == ARC_RECLAIM_CONS) {
- last_reclaim = ARC_RECLAIM_AGGR;
- } else {
- last_reclaim = ARC_RECLAIM_CONS;
- }
- } else {
- arc_no_grow = TRUE;
- last_reclaim = ARC_RECLAIM_AGGR;
- membar_producer();
- }
-
- /* reset the growth delay for every reclaim */
- arc_grow_time = ddi_get_lbolt() +
- (zfs_arc_grow_retry * hz);
-
- arc_kmem_reap_now(last_reclaim, 0);
- arc_warm = B_TRUE;
- }
-#else /* _KERNEL */
- mutex_exit(&arc_reclaim_lock);
-#endif /* !_KERNEL */
-
- /* No recent memory pressure allow the ARC to grow. */
- if (arc_no_grow &&
- ddi_time_after_eq(ddi_get_lbolt(), arc_grow_time))
- arc_no_grow = FALSE;
-
- arc_evicted = arc_adjust();
-
- /*
- * We're either no longer overflowing, or we
- * can't evict anything more, so we should wake
- * up any threads before we go to sleep.
- */
- if (arc_size <= arc_c || arc_evicted == 0)
- cv_broadcast(&arc_reclaim_waiters_cv);
-
- mutex_enter(&arc_reclaim_lock);
-
- /* block until needed, or one second, whichever is shorter */
- CALLB_CPR_SAFE_BEGIN(&cpr);
- (void) cv_timedwait_interruptible(&arc_reclaim_thread_cv,
- &arc_reclaim_lock, (ddi_get_lbolt() + hz));
- CALLB_CPR_SAFE_END(&cpr, &arc_reclaim_lock);
-
-
- /* Allow the module options to be changed */
- if (zfs_arc_max > 64 << 20 &&
- zfs_arc_max < physmem * PAGESIZE &&
- zfs_arc_max != arc_c_max)
- arc_c_max = zfs_arc_max;
-
- if (zfs_arc_min >= 2ULL << SPA_MAXBLOCKSHIFT &&
- zfs_arc_min <= arc_c_max &&
- zfs_arc_min != arc_c_min)
- arc_c_min = zfs_arc_min;
-
- if (zfs_arc_meta_limit > 0 &&
- zfs_arc_meta_limit <= arc_c_max &&
- zfs_arc_meta_limit != arc_meta_limit)
- arc_meta_limit = zfs_arc_meta_limit;
- }
-
- arc_reclaim_thread_exit = 0;
- cv_broadcast(&arc_reclaim_thread_cv);
- CALLB_CPR_EXIT(&cpr); /* drops arc_reclaim_lock */
- spl_fstrans_unmark(cookie);
- thread_exit();
-}
-
-static void
-arc_user_evicts_thread(void)
-{
- callb_cpr_t cpr;
- fstrans_cookie_t cookie;
-
- CALLB_CPR_INIT(&cpr, &arc_user_evicts_lock, callb_generic_cpr, FTAG);
-
- cookie = spl_fstrans_mark();
- mutex_enter(&arc_user_evicts_lock);
- while (!arc_user_evicts_thread_exit) {
- mutex_exit(&arc_user_evicts_lock);
-
- arc_do_user_evicts();
+ while (!arc_reclaim_thread_exit) {
+ int64_t to_free;
+ uint64_t evicted = 0;
+ uint64_t need_free = arc_need_free;
+ arc_tuning_update();
/*
* This is necessary in order for the mdb ::arc dcmd to
* structures can be queried directly if more accurate
* information is needed.
*/
+#ifndef __linux__
if (arc_ksp != NULL)
arc_ksp->ks_update(arc_ksp, KSTAT_READ);
+#endif
+ mutex_exit(&arc_reclaim_lock);
+
+ /*
+ * We call arc_adjust() before (possibly) calling
+ * arc_kmem_reap_now(), so that we can wake up
+ * arc_get_data_buf() sooner.
+ */
+ evicted = arc_adjust();
+
+ int64_t free_memory = arc_available_memory();
+ if (free_memory < 0) {
+
+ arc_no_grow = B_TRUE;
+ arc_warm = B_TRUE;
- mutex_enter(&arc_user_evicts_lock);
+ /*
+ * Wait at least zfs_grow_retry (default 5) seconds
+ * before considering growing.
+ */
+ growtime = gethrtime() + SEC2NSEC(arc_grow_retry);
+
+ arc_kmem_reap_now();
+
+ /*
+ * If we are still low on memory, shrink the ARC
+ * so that we have arc_shrink_min free space.
+ */
+ free_memory = arc_available_memory();
+
+ to_free = (arc_c >> arc_shrink_shift) - free_memory;
+ if (to_free > 0) {
+#ifdef _KERNEL
+ to_free = MAX(to_free, need_free);
+#endif
+ arc_shrink(to_free);
+ }
+ } else if (free_memory < arc_c >> arc_no_grow_shift) {
+ arc_no_grow = B_TRUE;
+ } else if (gethrtime() >= growtime) {
+ arc_no_grow = B_FALSE;
+ }
+
+ mutex_enter(&arc_reclaim_lock);
/*
- * Block until signaled, or after one second (we need to
- * call the arc's kstat update function regularly).
+ * If evicted is zero, we couldn't evict anything via
+ * arc_adjust(). This could be due to hash lock
+ * collisions, but more likely due to the majority of
+ * arc buffers being unevictable. Therefore, even if
+ * arc_size is above arc_c, another pass is unlikely to
+ * be helpful and could potentially cause us to enter an
+ * infinite loop.
*/
- CALLB_CPR_SAFE_BEGIN(&cpr);
- (void) cv_timedwait_interruptible(&arc_user_evicts_cv,
- &arc_user_evicts_lock, ddi_get_lbolt() + hz);
- CALLB_CPR_SAFE_END(&cpr, &arc_user_evicts_lock);
+ if (arc_size <= arc_c || evicted == 0) {
+ /*
+ * We're either no longer overflowing, or we
+ * can't evict anything more, so we should wake
+ * up any threads before we go to sleep and remove
+ * the bytes we were working on from arc_need_free
+ * since nothing more will be done here.
+ */
+ cv_broadcast(&arc_reclaim_waiters_cv);
+ ARCSTAT_INCR(arcstat_need_free, -need_free);
+
+ /*
+ * Block until signaled, or after one second (we
+ * might need to perform arc_kmem_reap_now()
+ * even if we aren't being signalled)
+ */
+ CALLB_CPR_SAFE_BEGIN(&cpr);
+ (void) cv_timedwait_sig_hires(&arc_reclaim_thread_cv,
+ &arc_reclaim_lock, SEC2NSEC(1), MSEC2NSEC(1), 0);
+ CALLB_CPR_SAFE_END(&cpr, &arc_reclaim_lock);
+ }
}
- arc_user_evicts_thread_exit = FALSE;
- cv_broadcast(&arc_user_evicts_cv);
- CALLB_CPR_EXIT(&cpr); /* drops arc_user_evicts_lock */
+ arc_reclaim_thread_exit = B_FALSE;
+ cv_broadcast(&arc_reclaim_thread_cv);
+ CALLB_CPR_EXIT(&cpr); /* drops arc_reclaim_lock */
spl_fstrans_unmark(cookie);
thread_exit();
}
* increase this negative difference.
*/
static uint64_t
-arc_evictable_memory(void) {
+arc_evictable_memory(void)
+{
uint64_t arc_clean =
- arc_mru->arcs_lsize[ARC_BUFC_DATA] +
- arc_mru->arcs_lsize[ARC_BUFC_METADATA] +
- arc_mfu->arcs_lsize[ARC_BUFC_DATA] +
- arc_mfu->arcs_lsize[ARC_BUFC_METADATA];
- uint64_t ghost_clean =
- arc_mru_ghost->arcs_lsize[ARC_BUFC_DATA] +
- arc_mru_ghost->arcs_lsize[ARC_BUFC_METADATA] +
- arc_mfu_ghost->arcs_lsize[ARC_BUFC_DATA] +
- arc_mfu_ghost->arcs_lsize[ARC_BUFC_METADATA];
+ refcount_count(&arc_mru->arcs_esize[ARC_BUFC_DATA]) +
+ refcount_count(&arc_mru->arcs_esize[ARC_BUFC_METADATA]) +
+ refcount_count(&arc_mfu->arcs_esize[ARC_BUFC_DATA]) +
+ refcount_count(&arc_mfu->arcs_esize[ARC_BUFC_METADATA]);
uint64_t arc_dirty = MAX((int64_t)arc_size - (int64_t)arc_clean, 0);
- if (arc_dirty >= arc_c_min)
- return (ghost_clean + arc_clean);
+ /*
+ * Scale reported evictable memory in proportion to page cache, cap
+ * at specified min/max.
+ */
+#ifdef ZFS_GLOBAL_NODE_PAGE_STATE
+ uint64_t min = (ptob(global_node_page_state(NR_FILE_PAGES)) / 100) *
+ zfs_arc_pc_percent;
+#else
+ uint64_t min = (ptob(global_page_state(NR_FILE_PAGES)) / 100) *
+ zfs_arc_pc_percent;
+#endif
+ min = MAX(arc_c_min, MIN(arc_c_max, min));
- return (ghost_clean + MAX((int64_t)arc_size - (int64_t)arc_c_min, 0));
+ if (arc_dirty >= min)
+ return (arc_clean);
+
+ return (MAX((int64_t)arc_size - (int64_t)min, 0));
}
/*
return (SHRINK_STOP);
/* Reclaim in progress */
- if (mutex_tryenter(&arc_reclaim_lock) == 0)
- return (SHRINK_STOP);
+ if (mutex_tryenter(&arc_reclaim_lock) == 0) {
+ ARCSTAT_INCR(arcstat_need_free, ptob(sc->nr_to_scan));
+ return (0);
+ }
mutex_exit(&arc_reclaim_lock);
/*
* Evict the requested number of pages by shrinking arc_c the
- * requested amount. If there is nothing left to evict just
- * reap whatever we can from the various arc slabs.
+ * requested amount.
*/
if (pages > 0) {
- arc_kmem_reap_now(ARC_RECLAIM_AGGR, ptob(sc->nr_to_scan));
-
+ arc_shrink(ptob(sc->nr_to_scan));
+ if (current_is_kswapd())
+ arc_kmem_reap_now();
#ifdef HAVE_SPLIT_SHRINKER_CALLBACK
- pages = MAX(pages - btop(arc_evictable_memory()), 0);
+ pages = MAX((int64_t)pages -
+ (int64_t)btop(arc_evictable_memory()), 0);
#else
pages = btop(arc_evictable_memory());
#endif
- } else {
- arc_kmem_reap_now(ARC_RECLAIM_CONS, ptob(sc->nr_to_scan));
+ /*
+ * We've shrunk what we can, wake up threads.
+ */
+ cv_broadcast(&arc_reclaim_waiters_cv);
+ } else
pages = SHRINK_STOP;
- }
-
- /*
- * We've reaped what we can, wake up threads.
- */
- cv_broadcast(&arc_reclaim_waiters_cv);
/*
* When direct reclaim is observed it usually indicates a rapid
ARCSTAT_BUMP(arcstat_memory_indirect_count);
} else {
arc_no_grow = B_TRUE;
- arc_grow_time = ddi_get_lbolt() + (zfs_arc_grow_retry * hz);
+ arc_kmem_reap_now();
ARCSTAT_BUMP(arcstat_memory_direct_count);
}
/*
* Adapt arc info given the number of bytes we are trying to add and
- * the state that we are comming from. This function is only called
+ * the state that we are coming from. This function is only called
* when we are adding new content to the cache.
*/
static void
arc_adapt(int bytes, arc_state_t *state)
{
int mult;
+ uint64_t arc_p_min = (arc_c >> arc_p_min_shift);
+ int64_t mrug_size = refcount_count(&arc_mru_ghost->arcs_size);
+ int64_t mfug_size = refcount_count(&arc_mfu_ghost->arcs_size);
if (state == arc_l2c_only)
return;
* target size of the MRU list.
*/
if (state == arc_mru_ghost) {
- mult = ((arc_mru_ghost->arcs_size >= arc_mfu_ghost->arcs_size) ?
- 1 : (arc_mfu_ghost->arcs_size/arc_mru_ghost->arcs_size));
-
+ mult = (mrug_size >= mfug_size) ? 1 : (mfug_size / mrug_size);
if (!zfs_arc_p_dampener_disable)
mult = MIN(mult, 10); /* avoid wild arc_p adjustment */
- arc_p = MIN(arc_c, arc_p + bytes * mult);
+ arc_p = MIN(arc_c - arc_p_min, arc_p + bytes * mult);
} else if (state == arc_mfu_ghost) {
uint64_t delta;
- mult = ((arc_mfu_ghost->arcs_size >= arc_mru_ghost->arcs_size) ?
- 1 : (arc_mru_ghost->arcs_size/arc_mfu_ghost->arcs_size));
-
+ mult = (mfug_size >= mrug_size) ? 1 : (mrug_size / mfug_size);
if (!zfs_arc_p_dampener_disable)
mult = MIN(mult, 10);
delta = MIN(bytes * mult, arc_p);
- arc_p = MAX(0, arc_p - delta);
+ arc_p = MAX(arc_p_min, arc_p - delta);
}
ASSERT((int64_t)arc_p >= 0);
+ if (arc_reclaim_needed()) {
+ cv_signal(&arc_reclaim_thread_cv);
+ return;
+ }
+
if (arc_no_grow)
return;
* If we're within (2 * maxblocksize) bytes of the target
* cache size, increment the target cache size
*/
- VERIFY3U(arc_c, >=, 2ULL << SPA_MAXBLOCKSHIFT);
+ ASSERT3U(arc_c, >=, 2ULL << SPA_MAXBLOCKSHIFT);
if (arc_size >= arc_c - (2ULL << SPA_MAXBLOCKSHIFT)) {
atomic_add_64(&arc_c, (int64_t)bytes);
if (arc_c > arc_c_max)
return (arc_size >= arc_c + overflow);
}
+static abd_t *
+arc_get_data_abd(arc_buf_hdr_t *hdr, uint64_t size, void *tag)
+{
+ arc_buf_contents_t type = arc_buf_type(hdr);
+
+ arc_get_data_impl(hdr, size, tag);
+ if (type == ARC_BUFC_METADATA) {
+ return (abd_alloc(size, B_TRUE));
+ } else {
+ ASSERT(type == ARC_BUFC_DATA);
+ return (abd_alloc(size, B_FALSE));
+ }
+}
+
+static void *
+arc_get_data_buf(arc_buf_hdr_t *hdr, uint64_t size, void *tag)
+{
+ arc_buf_contents_t type = arc_buf_type(hdr);
+
+ arc_get_data_impl(hdr, size, tag);
+ if (type == ARC_BUFC_METADATA) {
+ return (zio_buf_alloc(size));
+ } else {
+ ASSERT(type == ARC_BUFC_DATA);
+ return (zio_data_buf_alloc(size));
+ }
+}
+
/*
- * The buffer, supplied as the first argument, needs a data block. If we
- * are hitting the hard limit for the cache size, we must sleep, waiting
- * for the eviction thread to catch up. If we're past the target size
- * but below the hard limit, we'll only signal the reclaim thread and
- * continue on.
+ * Allocate a block and return it to the caller. If we are hitting the
+ * hard limit for the cache size, we must sleep, waiting for the eviction
+ * thread to catch up. If we're past the target size but below the hard
+ * limit, we'll only signal the reclaim thread and continue on.
*/
static void
-arc_get_data_buf(arc_buf_t *buf)
+arc_get_data_impl(arc_buf_hdr_t *hdr, uint64_t size, void *tag)
{
- arc_state_t *state = buf->b_hdr->b_l1hdr.b_state;
- uint64_t size = buf->b_hdr->b_size;
- arc_buf_contents_t type = arc_buf_type(buf->b_hdr);
+ arc_state_t *state = hdr->b_l1hdr.b_state;
+ arc_buf_contents_t type = arc_buf_type(hdr);
arc_adapt(size, state);
mutex_exit(&arc_reclaim_lock);
}
+ VERIFY3U(hdr->b_type, ==, type);
if (type == ARC_BUFC_METADATA) {
- buf->b_data = zio_buf_alloc(size);
arc_space_consume(size, ARC_SPACE_META);
} else {
- ASSERT(type == ARC_BUFC_DATA);
- buf->b_data = zio_data_buf_alloc(size);
arc_space_consume(size, ARC_SPACE_DATA);
}
* Update the state size. Note that ghost states have a
* "ghost size" and so don't need to be updated.
*/
- if (!GHOST_STATE(buf->b_hdr->b_l1hdr.b_state)) {
- arc_buf_hdr_t *hdr = buf->b_hdr;
+ if (!GHOST_STATE(state)) {
- atomic_add_64(&hdr->b_l1hdr.b_state->arcs_size, size);
+ (void) refcount_add_many(&state->arcs_size, size, tag);
/*
* If this is reached via arc_read, the link is
*/
if (multilist_link_active(&hdr->b_l1hdr.b_arc_node)) {
ASSERT(refcount_is_zero(&hdr->b_l1hdr.b_refcnt));
- atomic_add_64(&hdr->b_l1hdr.b_state->arcs_lsize[type],
- size);
+ (void) refcount_add_many(&state->arcs_esize[type],
+ size, tag);
}
+
/*
* If we are growing the cache, and we are adding anonymous
* data, and we have outgrown arc_p, update arc_p
*/
if (arc_size < arc_c && hdr->b_l1hdr.b_state == arc_anon &&
- arc_anon->arcs_size + arc_mru->arcs_size > arc_p)
+ (refcount_count(&arc_anon->arcs_size) +
+ refcount_count(&arc_mru->arcs_size) > arc_p))
arc_p = MIN(arc_c, arc_p + size);
}
}
+static void
+arc_free_data_abd(arc_buf_hdr_t *hdr, abd_t *abd, uint64_t size, void *tag)
+{
+ arc_free_data_impl(hdr, size, tag);
+ abd_free(abd);
+}
+
+static void
+arc_free_data_buf(arc_buf_hdr_t *hdr, void *buf, uint64_t size, void *tag)
+{
+ arc_buf_contents_t type = arc_buf_type(hdr);
+
+ arc_free_data_impl(hdr, size, tag);
+ if (type == ARC_BUFC_METADATA) {
+ zio_buf_free(buf, size);
+ } else {
+ ASSERT(type == ARC_BUFC_DATA);
+ zio_data_buf_free(buf, size);
+ }
+}
+
+/*
+ * Free the arc data buffer.
+ */
+static void
+arc_free_data_impl(arc_buf_hdr_t *hdr, uint64_t size, void *tag)
+{
+ arc_state_t *state = hdr->b_l1hdr.b_state;
+ arc_buf_contents_t type = arc_buf_type(hdr);
+
+ /* protected by hash lock, if in the hash table */
+ if (multilist_link_active(&hdr->b_l1hdr.b_arc_node)) {
+ ASSERT(refcount_is_zero(&hdr->b_l1hdr.b_refcnt));
+ ASSERT(state != arc_anon && state != arc_l2c_only);
+
+ (void) refcount_remove_many(&state->arcs_esize[type],
+ size, tag);
+ }
+ (void) refcount_remove_many(&state->arcs_size, size, tag);
+
+ VERIFY3U(hdr->b_type, ==, type);
+ if (type == ARC_BUFC_METADATA) {
+ arc_space_return(size, ARC_SPACE_META);
+ } else {
+ ASSERT(type == ARC_BUFC_DATA);
+ arc_space_return(size, ARC_SPACE_DATA);
+ }
+}
+
/*
* This routine is called whenever a buffer is accessed.
* NOTE: the hash lock is dropped in this function.
ASSERT(multilist_link_active(
&hdr->b_l1hdr.b_arc_node));
} else {
- hdr->b_flags &= ~ARC_FLAG_PREFETCH;
+ arc_hdr_clear_flags(hdr, ARC_FLAG_PREFETCH);
atomic_inc_32(&hdr->b_l1hdr.b_mru_hits);
ARCSTAT_BUMP(arcstat_mru_hits);
}
if (HDR_PREFETCH(hdr)) {
new_state = arc_mru;
if (refcount_count(&hdr->b_l1hdr.b_refcnt) > 0)
- hdr->b_flags &= ~ARC_FLAG_PREFETCH;
+ arc_hdr_clear_flags(hdr, ARC_FLAG_PREFETCH);
DTRACE_PROBE1(new_state__mru, arc_buf_hdr_t *, hdr);
} else {
new_state = arc_mfu;
}
}
-/* a generic arc_done_func_t which you can use */
+/* a generic arc_read_done_func_t which you can use */
/* ARGSUSED */
void
-arc_bcopy_func(zio_t *zio, arc_buf_t *buf, void *arg)
+arc_bcopy_func(zio_t *zio, int error, arc_buf_t *buf, void *arg)
{
- if (zio == NULL || zio->io_error == 0)
- bcopy(buf->b_data, arg, buf->b_hdr->b_size);
- VERIFY(arc_buf_remove_ref(buf, arg));
+ if (error == 0)
+ bcopy(buf->b_data, arg, arc_buf_size(buf));
+ arc_buf_destroy(buf, arg);
}
-/* a generic arc_done_func_t */
+/* a generic arc_read_done_func_t */
void
-arc_getbuf_func(zio_t *zio, arc_buf_t *buf, void *arg)
+arc_getbuf_func(zio_t *zio, int error, arc_buf_t *buf, void *arg)
{
arc_buf_t **bufp = arg;
- if (zio && zio->io_error) {
- VERIFY(arc_buf_remove_ref(buf, arg));
+ if (error != 0) {
+ arc_buf_destroy(buf, arg);
*bufp = NULL;
} else {
*bufp = buf;
}
}
+static void
+arc_hdr_verify(arc_buf_hdr_t *hdr, blkptr_t *bp)
+{
+ if (BP_IS_HOLE(bp) || BP_IS_EMBEDDED(bp)) {
+ ASSERT3U(HDR_GET_PSIZE(hdr), ==, 0);
+ ASSERT3U(arc_hdr_get_compress(hdr), ==, ZIO_COMPRESS_OFF);
+ } else {
+ if (HDR_COMPRESSION_ENABLED(hdr)) {
+ ASSERT3U(arc_hdr_get_compress(hdr), ==,
+ BP_GET_COMPRESS(bp));
+ }
+ ASSERT3U(HDR_GET_LSIZE(hdr), ==, BP_GET_LSIZE(bp));
+ ASSERT3U(HDR_GET_PSIZE(hdr), ==, BP_GET_PSIZE(bp));
+ ASSERT3U(!!HDR_PROTECTED(hdr), ==, BP_IS_PROTECTED(bp));
+ }
+}
+
static void
arc_read_done(zio_t *zio)
{
- arc_buf_hdr_t *hdr;
- arc_buf_t *buf;
- arc_buf_t *abuf; /* buffer we're assigning to callback */
+ blkptr_t *bp = zio->io_bp;
+ arc_buf_hdr_t *hdr = zio->io_private;
kmutex_t *hash_lock = NULL;
- arc_callback_t *callback_list, *acb;
- int freeable = FALSE;
-
- buf = zio->io_private;
- hdr = buf->b_hdr;
+ arc_callback_t *callback_list;
+ arc_callback_t *acb;
+ boolean_t freeable = B_FALSE;
+ boolean_t no_zio_error = (zio->io_error == 0);
/*
* The hdr was inserted into hash-table and removed from lists
ASSERT3U(hdr->b_dva.dva_word[1], ==,
BP_IDENTITY(zio->io_bp)->dva_word[1]);
- found = buf_hash_find(hdr->b_spa, zio->io_bp,
- &hash_lock);
+ found = buf_hash_find(hdr->b_spa, zio->io_bp, &hash_lock);
- ASSERT((found == NULL && HDR_FREED_IN_READ(hdr) &&
- hash_lock == NULL) ||
- (found == hdr &&
+ ASSERT((found == hdr &&
DVA_EQUAL(&hdr->b_dva, BP_IDENTITY(zio->io_bp))) ||
(found == hdr && HDR_L2_READING(hdr)));
+ ASSERT3P(hash_lock, !=, NULL);
}
- hdr->b_flags &= ~ARC_FLAG_L2_EVICTED;
- if (l2arc_noprefetch && HDR_PREFETCH(hdr))
- hdr->b_flags &= ~ARC_FLAG_L2CACHE;
+ if (BP_IS_PROTECTED(bp)) {
+ hdr->b_crypt_hdr.b_ot = BP_GET_TYPE(bp);
+ hdr->b_crypt_hdr.b_dsobj = zio->io_bookmark.zb_objset;
+ zio_crypt_decode_params_bp(bp, hdr->b_crypt_hdr.b_salt,
+ hdr->b_crypt_hdr.b_iv);
- /* byteswap if necessary */
- callback_list = hdr->b_l1hdr.b_acb;
- ASSERT(callback_list != NULL);
- if (BP_SHOULD_BYTESWAP(zio->io_bp) && zio->io_error == 0) {
- dmu_object_byteswap_t bswap =
- DMU_OT_BYTESWAP(BP_GET_TYPE(zio->io_bp));
- if (BP_GET_LEVEL(zio->io_bp) > 0)
- byteswap_uint64_array(buf->b_data, hdr->b_size);
- else
- dmu_ot_byteswap[bswap].ob_func(buf->b_data, hdr->b_size);
+ if (BP_GET_TYPE(bp) == DMU_OT_INTENT_LOG) {
+ void *tmpbuf;
+
+ tmpbuf = abd_borrow_buf_copy(zio->io_abd,
+ sizeof (zil_chain_t));
+ zio_crypt_decode_mac_zil(tmpbuf,
+ hdr->b_crypt_hdr.b_mac);
+ abd_return_buf(zio->io_abd, tmpbuf,
+ sizeof (zil_chain_t));
+ } else {
+ zio_crypt_decode_mac_bp(bp, hdr->b_crypt_hdr.b_mac);
+ }
}
- arc_cksum_compute(buf, B_FALSE);
- arc_buf_watch(buf);
+ if (no_zio_error) {
+ /* byteswap if necessary */
+ if (BP_SHOULD_BYTESWAP(zio->io_bp)) {
+ if (BP_GET_LEVEL(zio->io_bp) > 0) {
+ hdr->b_l1hdr.b_byteswap = DMU_BSWAP_UINT64;
+ } else {
+ hdr->b_l1hdr.b_byteswap =
+ DMU_OT_BYTESWAP(BP_GET_TYPE(zio->io_bp));
+ }
+ } else {
+ hdr->b_l1hdr.b_byteswap = DMU_BSWAP_NUMFUNCS;
+ }
+ }
+
+ arc_hdr_clear_flags(hdr, ARC_FLAG_L2_EVICTED);
+ if (l2arc_noprefetch && HDR_PREFETCH(hdr))
+ arc_hdr_clear_flags(hdr, ARC_FLAG_L2CACHE);
- if (hash_lock && zio->io_error == 0 &&
- hdr->b_l1hdr.b_state == arc_anon) {
+ callback_list = hdr->b_l1hdr.b_acb;
+ ASSERT3P(callback_list, !=, NULL);
+
+ if (hash_lock && no_zio_error && hdr->b_l1hdr.b_state == arc_anon) {
/*
* Only call arc_access on anonymous buffers. This is because
* if we've issued an I/O for an evicted buffer, we've already
arc_access(hdr, hash_lock);
}
- /* create copies of the data buffer for the callers */
- abuf = buf;
- for (acb = callback_list; acb; acb = acb->acb_next) {
- if (acb->acb_done) {
- if (abuf == NULL) {
- ARCSTAT_BUMP(arcstat_duplicate_reads);
- abuf = arc_buf_clone(buf);
+ /*
+ * If a read request has a callback (i.e. acb_done is not NULL), then we
+ * make a buf containing the data according to the parameters which were
+ * passed in. The implementation of arc_buf_alloc_impl() ensures that we
+ * aren't needlessly decompressing the data multiple times.
+ */
+ int callback_cnt = 0;
+ for (acb = callback_list; acb != NULL; acb = acb->acb_next) {
+ if (!acb->acb_done)
+ continue;
+
+ /* This is a demand read since prefetches don't use callbacks */
+ callback_cnt++;
+
+ int error = arc_buf_alloc_impl(hdr, zio->io_spa,
+ zio->io_bookmark.zb_objset, acb->acb_private,
+ acb->acb_encrypted, acb->acb_compressed, acb->acb_noauth,
+ no_zio_error, &acb->acb_buf);
+
+ /*
+ * assert non-speculative zios didn't fail because an
+ * encryption key wasn't loaded
+ */
+ ASSERT((zio->io_flags & ZIO_FLAG_SPECULATIVE) ||
+ error == 0 || error != ENOENT);
+
+ /*
+ * If we failed to decrypt, report an error now (as the zio
+ * layer would have done if it had done the transforms).
+ */
+ if (error == ECKSUM) {
+ ASSERT(BP_IS_PROTECTED(bp));
+ error = SET_ERROR(EIO);
+ spa_log_error(zio->io_spa, &zio->io_bookmark);
+ if ((zio->io_flags & ZIO_FLAG_SPECULATIVE) == 0) {
+ zfs_ereport_post(FM_EREPORT_ZFS_AUTHENTICATION,
+ zio->io_spa, NULL, &zio->io_bookmark, zio,
+ 0, 0);
}
- acb->acb_buf = abuf;
- abuf = NULL;
+ }
+
+ if (no_zio_error) {
+ zio->io_error = error;
}
}
hdr->b_l1hdr.b_acb = NULL;
- hdr->b_flags &= ~ARC_FLAG_IO_IN_PROGRESS;
- ASSERT(!HDR_BUF_AVAILABLE(hdr));
- if (abuf == buf) {
- ASSERT(buf->b_efunc == NULL);
- ASSERT(hdr->b_l1hdr.b_datacnt == 1);
- hdr->b_flags |= ARC_FLAG_BUF_AVAILABLE;
+ arc_hdr_clear_flags(hdr, ARC_FLAG_IO_IN_PROGRESS);
+ if (callback_cnt == 0) {
+ ASSERT(HDR_PREFETCH(hdr) || HDR_HAS_RABD(hdr));
+ ASSERT(hdr->b_l1hdr.b_pabd != NULL || HDR_HAS_RABD(hdr));
}
ASSERT(refcount_is_zero(&hdr->b_l1hdr.b_refcnt) ||
callback_list != NULL);
- if (zio->io_error != 0) {
- hdr->b_flags |= ARC_FLAG_IO_ERROR;
+ if (no_zio_error) {
+ arc_hdr_verify(hdr, zio->io_bp);
+ } else {
+ arc_hdr_set_flags(hdr, ARC_FLAG_IO_ERROR);
if (hdr->b_l1hdr.b_state != arc_anon)
arc_change_state(arc_anon, hdr, hash_lock);
if (HDR_IN_HASH_TABLE(hdr))
/* execute each callback and free its structure */
while ((acb = callback_list) != NULL) {
- if (acb->acb_done)
- acb->acb_done(zio, acb->acb_buf, acb->acb_private);
+ if (acb->acb_done) {
+ acb->acb_done(zio, zio->io_error, acb->acb_buf,
+ acb->acb_private);
+ }
if (acb->acb_zio_dummy != NULL) {
acb->acb_zio_dummy->io_error = zio->io_error;
* for readers of this block.
*/
int
-arc_read(zio_t *pio, spa_t *spa, const blkptr_t *bp, arc_done_func_t *done,
- void *private, zio_priority_t priority, int zio_flags,
- arc_flags_t *arc_flags, const zbookmark_phys_t *zb)
+arc_read(zio_t *pio, spa_t *spa, const blkptr_t *bp,
+ arc_read_done_func_t *done, void *private, zio_priority_t priority,
+ int zio_flags, arc_flags_t *arc_flags, const zbookmark_phys_t *zb)
{
arc_buf_hdr_t *hdr = NULL;
- arc_buf_t *buf = NULL;
kmutex_t *hash_lock = NULL;
zio_t *rzio;
uint64_t guid = spa_load_guid(spa);
+ boolean_t compressed_read = (zio_flags & ZIO_FLAG_RAW_COMPRESS) != 0;
+ boolean_t encrypted_read = BP_IS_ENCRYPTED(bp) &&
+ (zio_flags & ZIO_FLAG_RAW_ENCRYPT) != 0;
+ boolean_t noauth_read = BP_IS_AUTHENTICATED(bp) &&
+ (zio_flags & ZIO_FLAG_RAW_ENCRYPT) != 0;
int rc = 0;
ASSERT(!BP_IS_EMBEDDED(bp) ||
hdr = buf_hash_find(guid, bp, &hash_lock);
}
- if (hdr != NULL && HDR_HAS_L1HDR(hdr) && hdr->b_l1hdr.b_datacnt > 0) {
-
+ /*
+ * Determine if we have an L1 cache hit or a cache miss. For simplicity
+ * we maintain encrypted data seperately from compressed / uncompressed
+ * data. If the user is requesting raw encrypted data and we don't have
+ * that in the header we will read from disk to guarantee that we can
+ * get it even if the encryption keys aren't loaded.
+ */
+ if (hdr != NULL && HDR_HAS_L1HDR(hdr) && (HDR_HAS_RABD(hdr) ||
+ (hdr->b_l1hdr.b_pabd != NULL && !encrypted_read))) {
+ arc_buf_t *buf = NULL;
*arc_flags |= ARC_FLAG_CACHED;
if (HDR_IO_IN_PROGRESS(hdr)) {
+ if ((hdr->b_flags & ARC_FLAG_PRIO_ASYNC_READ) &&
+ priority == ZIO_PRIORITY_SYNC_READ) {
+ /*
+ * This sync read must wait for an
+ * in-progress async read (e.g. a predictive
+ * prefetch). Async reads are queued
+ * separately at the vdev_queue layer, so
+ * this is a form of priority inversion.
+ * Ideally, we would "inherit" the demand
+ * i/o's priority by moving the i/o from
+ * the async queue to the synchronous queue,
+ * but there is currently no mechanism to do
+ * so. Track this so that we can evaluate
+ * the magnitude of this potential performance
+ * problem.
+ *
+ * Note that if the prefetch i/o is already
+ * active (has been issued to the device),
+ * the prefetch improved performance, because
+ * we issued it sooner than we would have
+ * without the prefetch.
+ */
+ DTRACE_PROBE1(arc__sync__wait__for__async,
+ arc_buf_hdr_t *, hdr);
+ ARCSTAT_BUMP(arcstat_sync_wait_for_async);
+ }
+ if (hdr->b_flags & ARC_FLAG_PREDICTIVE_PREFETCH) {
+ arc_hdr_clear_flags(hdr,
+ ARC_FLAG_PREDICTIVE_PREFETCH);
+ }
+
if (*arc_flags & ARC_FLAG_WAIT) {
cv_wait(&hdr->b_l1hdr.b_cv, hash_lock);
mutex_exit(hash_lock);
ASSERT(*arc_flags & ARC_FLAG_NOWAIT);
if (done) {
- arc_callback_t *acb = NULL;
+ arc_callback_t *acb = NULL;
acb = kmem_zalloc(sizeof (arc_callback_t),
KM_SLEEP);
acb->acb_done = done;
acb->acb_private = private;
+ acb->acb_compressed = compressed_read;
if (pio != NULL)
acb->acb_zio_dummy = zio_null(pio,
spa, NULL, NULL, NULL, zio_flags);
- ASSERT(acb->acb_done != NULL);
+ ASSERT3P(acb->acb_done, !=, NULL);
acb->acb_next = hdr->b_l1hdr.b_acb;
hdr->b_l1hdr.b_acb = acb;
- add_reference(hdr, hash_lock, private);
mutex_exit(hash_lock);
goto out;
}
hdr->b_l1hdr.b_state == arc_mfu);
if (done) {
- add_reference(hdr, hash_lock, private);
- /*
- * If this block is already in use, create a new
- * copy of the data so that we will be guaranteed
- * that arc_release() will always succeed.
- */
- buf = hdr->b_l1hdr.b_buf;
- ASSERT(buf);
- ASSERT(buf->b_data);
- if (HDR_BUF_AVAILABLE(hdr)) {
- ASSERT(buf->b_efunc == NULL);
- hdr->b_flags &= ~ARC_FLAG_BUF_AVAILABLE;
- } else {
- buf = arc_buf_clone(buf);
+ if (hdr->b_flags & ARC_FLAG_PREDICTIVE_PREFETCH) {
+ /*
+ * This is a demand read which does not have to
+ * wait for i/o because we did a predictive
+ * prefetch i/o for it, which has completed.
+ */
+ DTRACE_PROBE1(
+ arc__demand__hit__predictive__prefetch,
+ arc_buf_hdr_t *, hdr);
+ ARCSTAT_BUMP(
+ arcstat_demand_hit_predictive_prefetch);
+ arc_hdr_clear_flags(hdr,
+ ARC_FLAG_PREDICTIVE_PREFETCH);
}
+ ASSERT(!BP_IS_EMBEDDED(bp) || !BP_IS_HOLE(bp));
+
+ /* Get a buf with the desired data in it. */
+ rc = arc_buf_alloc_impl(hdr, spa, zb->zb_objset,
+ private, encrypted_read, compressed_read,
+ noauth_read, B_TRUE, &buf);
+ ASSERT((zio_flags & ZIO_FLAG_SPECULATIVE) ||
+ rc == 0 || rc != ENOENT);
} else if (*arc_flags & ARC_FLAG_PREFETCH &&
refcount_count(&hdr->b_l1hdr.b_refcnt) == 0) {
- hdr->b_flags |= ARC_FLAG_PREFETCH;
+ arc_hdr_set_flags(hdr, ARC_FLAG_PREFETCH);
}
DTRACE_PROBE1(arc__hit, arc_buf_hdr_t *, hdr);
arc_access(hdr, hash_lock);
if (*arc_flags & ARC_FLAG_L2CACHE)
- hdr->b_flags |= ARC_FLAG_L2CACHE;
- if (*arc_flags & ARC_FLAG_L2COMPRESS)
- hdr->b_flags |= ARC_FLAG_L2COMPRESS;
+ arc_hdr_set_flags(hdr, ARC_FLAG_L2CACHE);
mutex_exit(hash_lock);
ARCSTAT_BUMP(arcstat_hits);
ARCSTAT_CONDSTAT(!HDR_PREFETCH(hdr),
data, metadata, hits);
if (done)
- done(NULL, buf, private);
+ done(NULL, rc, buf, private);
} else {
- uint64_t size = BP_GET_LSIZE(bp);
+ uint64_t lsize = BP_GET_LSIZE(bp);
+ uint64_t psize = BP_GET_PSIZE(bp);
arc_callback_t *acb;
vdev_t *vd = NULL;
uint64_t addr = 0;
boolean_t devw = B_FALSE;
- enum zio_compress b_compress = ZIO_COMPRESS_OFF;
- int32_t b_asize = 0;
+ uint64_t size;
+ void *hdr_abd;
/*
* Gracefully handle a damaged logical block size as a
- * checksum error by passing a dummy zio to the done callback.
+ * checksum error.
*/
- if (size > spa_maxblocksize(spa)) {
- if (done) {
- rzio = zio_null(pio, spa, NULL,
- NULL, NULL, zio_flags);
- rzio->io_error = ECKSUM;
- done(rzio, buf, private);
- zio_nowait(rzio);
- }
- rc = ECKSUM;
+ if (lsize > spa_maxblocksize(spa)) {
+ rc = SET_ERROR(ECKSUM);
goto out;
}
/* this block is not in the cache */
arc_buf_hdr_t *exists = NULL;
arc_buf_contents_t type = BP_GET_BUFC_TYPE(bp);
- buf = arc_buf_alloc(spa, size, private, type);
- hdr = buf->b_hdr;
+ hdr = arc_hdr_alloc(spa_load_guid(spa), psize, lsize,
+ BP_IS_PROTECTED(bp), BP_GET_COMPRESS(bp), type,
+ encrypted_read);
+
if (!BP_IS_EMBEDDED(bp)) {
hdr->b_dva = *BP_IDENTITY(bp);
hdr->b_birth = BP_PHYSICAL_BIRTH(bp);
/* somebody beat us to the hash insert */
mutex_exit(hash_lock);
buf_discard_identity(hdr);
- (void) arc_buf_remove_ref(buf, private);
+ arc_hdr_destroy(hdr);
goto top; /* restart the IO request */
}
-
- /* if this is a prefetch, we don't have a reference */
- if (*arc_flags & ARC_FLAG_PREFETCH) {
- (void) remove_reference(hdr, hash_lock,
- private);
- hdr->b_flags |= ARC_FLAG_PREFETCH;
- }
- if (*arc_flags & ARC_FLAG_L2CACHE)
- hdr->b_flags |= ARC_FLAG_L2CACHE;
- if (*arc_flags & ARC_FLAG_L2COMPRESS)
- hdr->b_flags |= ARC_FLAG_L2COMPRESS;
- if (BP_GET_LEVEL(bp) > 0)
- hdr->b_flags |= ARC_FLAG_INDIRECT;
} else {
/*
- * This block is in the ghost cache. If it was L2-only
- * (and thus didn't have an L1 hdr), we realloc the
- * header to add an L1 hdr.
+ * This block is in the ghost cache or encrypted data
+ * was requested and we didn't have it. If it was
+ * L2-only (and thus didn't have an L1 hdr),
+ * we realloc the header to add an L1 hdr.
*/
if (!HDR_HAS_L1HDR(hdr)) {
hdr = arc_hdr_realloc(hdr, hdr_l2only_cache,
hdr_full_cache);
}
- ASSERT(GHOST_STATE(hdr->b_l1hdr.b_state));
- ASSERT(!HDR_IO_IN_PROGRESS(hdr));
- ASSERT(refcount_is_zero(&hdr->b_l1hdr.b_refcnt));
- ASSERT3P(hdr->b_l1hdr.b_buf, ==, NULL);
+ if (GHOST_STATE(hdr->b_l1hdr.b_state)) {
+ ASSERT3P(hdr->b_l1hdr.b_pabd, ==, NULL);
+ ASSERT(!HDR_HAS_RABD(hdr));
+ ASSERT(!HDR_IO_IN_PROGRESS(hdr));
+ ASSERT0(refcount_count(&hdr->b_l1hdr.b_refcnt));
+ ASSERT3P(hdr->b_l1hdr.b_buf, ==, NULL);
+ ASSERT3P(hdr->b_l1hdr.b_freeze_cksum, ==, NULL);
+ } else if (HDR_IO_IN_PROGRESS(hdr)) {
+ /*
+ * If this header already had an IO in progress
+ * and we are performing another IO to fetch
+ * encrypted data we must wait until the first
+ * IO completes so as not to confuse
+ * arc_read_done(). This should be very rare
+ * and so the performance impact shouldn't
+ * matter.
+ */
+ cv_wait(&hdr->b_l1hdr.b_cv, hash_lock);
+ mutex_exit(hash_lock);
+ goto top;
+ }
- /* if this is a prefetch, we don't have a reference */
- if (*arc_flags & ARC_FLAG_PREFETCH)
- hdr->b_flags |= ARC_FLAG_PREFETCH;
- else
- add_reference(hdr, hash_lock, private);
- if (*arc_flags & ARC_FLAG_L2CACHE)
- hdr->b_flags |= ARC_FLAG_L2CACHE;
- if (*arc_flags & ARC_FLAG_L2COMPRESS)
- hdr->b_flags |= ARC_FLAG_L2COMPRESS;
- buf = kmem_cache_alloc(buf_cache, KM_PUSHPAGE);
- buf->b_hdr = hdr;
- buf->b_data = NULL;
- buf->b_efunc = NULL;
- buf->b_private = NULL;
- buf->b_next = NULL;
- hdr->b_l1hdr.b_buf = buf;
- ASSERT0(hdr->b_l1hdr.b_datacnt);
- hdr->b_l1hdr.b_datacnt = 1;
- arc_get_data_buf(buf);
+ /*
+ * This is a delicate dance that we play here.
+ * This hdr might be in the ghost list so we access
+ * it to move it out of the ghost list before we
+ * initiate the read. If it's a prefetch then
+ * it won't have a callback so we'll remove the
+ * reference that arc_buf_alloc_impl() created. We
+ * do this after we've called arc_access() to
+ * avoid hitting an assert in remove_reference().
+ */
arc_access(hdr, hash_lock);
+ arc_hdr_alloc_abd(hdr, encrypted_read);
+ }
+
+ if (encrypted_read) {
+ ASSERT(HDR_HAS_RABD(hdr));
+ size = HDR_GET_PSIZE(hdr);
+ hdr_abd = hdr->b_crypt_hdr.b_rabd;
+ zio_flags |= ZIO_FLAG_RAW;
+ } else {
+ ASSERT3P(hdr->b_l1hdr.b_pabd, !=, NULL);
+ size = arc_hdr_size(hdr);
+ hdr_abd = hdr->b_l1hdr.b_pabd;
+
+ if (arc_hdr_get_compress(hdr) != ZIO_COMPRESS_OFF) {
+ zio_flags |= ZIO_FLAG_RAW_COMPRESS;
+ }
+
+ /*
+ * For authenticated bp's, we do not ask the ZIO layer
+ * to authenticate them since this will cause the entire
+ * IO to fail if the key isn't loaded. Instead, we
+ * defer authentication until arc_buf_fill(), which will
+ * verify the data when the key is available.
+ */
+ if (BP_IS_AUTHENTICATED(bp))
+ zio_flags |= ZIO_FLAG_RAW_ENCRYPT;
}
+ if (*arc_flags & ARC_FLAG_PREFETCH &&
+ refcount_is_zero(&hdr->b_l1hdr.b_refcnt))
+ arc_hdr_set_flags(hdr, ARC_FLAG_PREFETCH);
+ if (*arc_flags & ARC_FLAG_L2CACHE)
+ arc_hdr_set_flags(hdr, ARC_FLAG_L2CACHE);
+ if (BP_IS_AUTHENTICATED(bp))
+ arc_hdr_set_flags(hdr, ARC_FLAG_NOAUTH);
+ if (BP_GET_LEVEL(bp) > 0)
+ arc_hdr_set_flags(hdr, ARC_FLAG_INDIRECT);
+ if (*arc_flags & ARC_FLAG_PREDICTIVE_PREFETCH)
+ arc_hdr_set_flags(hdr, ARC_FLAG_PREDICTIVE_PREFETCH);
ASSERT(!GHOST_STATE(hdr->b_l1hdr.b_state));
acb = kmem_zalloc(sizeof (arc_callback_t), KM_SLEEP);
acb->acb_done = done;
acb->acb_private = private;
+ acb->acb_compressed = compressed_read;
+ acb->acb_encrypted = encrypted_read;
+ acb->acb_noauth = noauth_read;
- ASSERT(hdr->b_l1hdr.b_acb == NULL);
+ ASSERT3P(hdr->b_l1hdr.b_acb, ==, NULL);
hdr->b_l1hdr.b_acb = acb;
- hdr->b_flags |= ARC_FLAG_IO_IN_PROGRESS;
+ arc_hdr_set_flags(hdr, ARC_FLAG_IO_IN_PROGRESS);
if (HDR_HAS_L2HDR(hdr) &&
(vd = hdr->b_l2hdr.b_dev->l2ad_vdev) != NULL) {
devw = hdr->b_l2hdr.b_dev->l2ad_writing;
addr = hdr->b_l2hdr.b_daddr;
- b_compress = HDR_GET_COMPRESS(hdr);
- b_asize = hdr->b_l2hdr.b_asize;
/*
* Lock out device removal.
*/
vd = NULL;
}
+ if (priority == ZIO_PRIORITY_ASYNC_READ)
+ arc_hdr_set_flags(hdr, ARC_FLAG_PRIO_ASYNC_READ);
+ else
+ arc_hdr_clear_flags(hdr, ARC_FLAG_PRIO_ASYNC_READ);
+
if (hash_lock != NULL)
mutex_exit(hash_lock);
* At this point, we have a level 1 cache miss. Try again in
* L2ARC if possible.
*/
- ASSERT3U(hdr->b_size, ==, size);
+ ASSERT3U(HDR_GET_LSIZE(hdr), ==, lsize);
+
DTRACE_PROBE4(arc__miss, arc_buf_hdr_t *, hdr, blkptr_t *, bp,
- uint64_t, size, zbookmark_phys_t *, zb);
+ uint64_t, lsize, zbookmark_phys_t *, zb);
ARCSTAT_BUMP(arcstat_misses);
ARCSTAT_CONDSTAT(!HDR_PREFETCH(hdr),
demand, prefetch, !HDR_ISTYPE_METADATA(hdr),
!HDR_L2_WRITING(hdr) && !HDR_L2_EVICTED(hdr) &&
!(l2arc_noprefetch && HDR_PREFETCH(hdr))) {
l2arc_read_callback_t *cb;
+ abd_t *abd;
+ uint64_t asize;
DTRACE_PROBE1(l2arc__hit, arc_buf_hdr_t *, hdr);
ARCSTAT_BUMP(arcstat_l2_hits);
cb = kmem_zalloc(sizeof (l2arc_read_callback_t),
KM_SLEEP);
- cb->l2rcb_buf = buf;
- cb->l2rcb_spa = spa;
+ cb->l2rcb_hdr = hdr;
cb->l2rcb_bp = *bp;
cb->l2rcb_zb = *zb;
cb->l2rcb_flags = zio_flags;
- cb->l2rcb_compress = b_compress;
+
+ asize = vdev_psize_to_asize(vd, size);
+ if (asize != size) {
+ abd = abd_alloc_for_io(asize,
+ HDR_ISTYPE_METADATA(hdr));
+ cb->l2rcb_abd = abd;
+ } else {
+ abd = hdr_abd;
+ }
ASSERT(addr >= VDEV_LABEL_START_SIZE &&
- addr + size < vd->vdev_psize -
+ addr + asize <= vd->vdev_psize -
VDEV_LABEL_END_SIZE);
/*
* Issue a null zio if the underlying buffer
* was squashed to zero size by compression.
*/
- if (b_compress == ZIO_COMPRESS_EMPTY) {
- rzio = zio_null(pio, spa, vd,
- l2arc_read_done, cb,
- zio_flags | ZIO_FLAG_DONT_CACHE |
- ZIO_FLAG_CANFAIL |
- ZIO_FLAG_DONT_PROPAGATE |
- ZIO_FLAG_DONT_RETRY);
- } else {
- rzio = zio_read_phys(pio, vd, addr,
- b_asize, buf->b_data,
- ZIO_CHECKSUM_OFF,
- l2arc_read_done, cb, priority,
- zio_flags | ZIO_FLAG_DONT_CACHE |
- ZIO_FLAG_CANFAIL |
- ZIO_FLAG_DONT_PROPAGATE |
- ZIO_FLAG_DONT_RETRY, B_FALSE);
- }
+ ASSERT3U(arc_hdr_get_compress(hdr), !=,
+ ZIO_COMPRESS_EMPTY);
+ rzio = zio_read_phys(pio, vd, addr,
+ asize, abd,
+ ZIO_CHECKSUM_OFF,
+ l2arc_read_done, cb, priority,
+ zio_flags | ZIO_FLAG_DONT_CACHE |
+ ZIO_FLAG_CANFAIL |
+ ZIO_FLAG_DONT_PROPAGATE |
+ ZIO_FLAG_DONT_RETRY, B_FALSE);
+
DTRACE_PROBE2(l2arc__read, vdev_t *, vd,
zio_t *, rzio);
- ARCSTAT_INCR(arcstat_l2_read_bytes, b_asize);
+ ARCSTAT_INCR(arcstat_l2_read_bytes,
+ HDR_GET_PSIZE(hdr));
if (*arc_flags & ARC_FLAG_NOWAIT) {
zio_nowait(rzio);
}
}
- rzio = zio_read(pio, spa, bp, buf->b_data, size,
- arc_read_done, buf, priority, zio_flags, zb);
+ rzio = zio_read(pio, spa, bp, hdr_abd, size,
+ arc_read_done, hdr, priority, zio_flags, zb);
if (*arc_flags & ARC_FLAG_WAIT) {
rc = zio_wait(rzio);
void
arc_remove_prune_callback(arc_prune_t *p)
{
+ boolean_t wait = B_FALSE;
mutex_enter(&arc_prune_mtx);
list_remove(&arc_prune_list, p);
- if (refcount_remove(&p->p_refcnt, &arc_prune_list) == 0) {
- refcount_destroy(&p->p_refcnt);
- kmem_free(p, sizeof (*p));
- }
+ if (refcount_remove(&p->p_refcnt, &arc_prune_list) > 0)
+ wait = B_TRUE;
mutex_exit(&arc_prune_mtx);
-}
-
-void
-arc_set_callback(arc_buf_t *buf, arc_evict_func_t *func, void *private)
-{
- ASSERT(buf->b_hdr != NULL);
- ASSERT(buf->b_hdr->b_l1hdr.b_state != arc_anon);
- ASSERT(!refcount_is_zero(&buf->b_hdr->b_l1hdr.b_refcnt) ||
- func == NULL);
- ASSERT(buf->b_efunc == NULL);
- ASSERT(!HDR_BUF_AVAILABLE(buf->b_hdr));
- buf->b_efunc = func;
- buf->b_private = private;
+ /* wait for arc_prune_task to finish */
+ if (wait)
+ taskq_wait_outstanding(arc_prune_taskq, 0);
+ ASSERT0(refcount_count(&p->p_refcnt));
+ refcount_destroy(&p->p_refcnt);
+ kmem_free(p, sizeof (*p));
}
/*
hdr = buf_hash_find(guid, bp, &hash_lock);
if (hdr == NULL)
return;
- if (HDR_BUF_AVAILABLE(hdr)) {
- arc_buf_t *buf = hdr->b_l1hdr.b_buf;
- add_reference(hdr, hash_lock, FTAG);
- hdr->b_flags &= ~ARC_FLAG_BUF_AVAILABLE;
- mutex_exit(hash_lock);
- arc_release(buf, FTAG);
- (void) arc_buf_remove_ref(buf, FTAG);
- } else {
+ /*
+ * We might be trying to free a block that is still doing I/O
+ * (i.e. prefetch) or has a reference (i.e. a dedup-ed,
+ * dmu_sync-ed block). If this block is being prefetched, then it
+ * would still have the ARC_FLAG_IO_IN_PROGRESS flag set on the hdr
+ * until the I/O completes. A block may also have a reference if it is
+ * part of a dedup-ed, dmu_synced write. The dmu_sync() function would
+ * have written the new block to its final resting place on disk but
+ * without the dedup flag set. This would have left the hdr in the MRU
+ * state and discoverable. When the txg finally syncs it detects that
+ * the block was overridden in open context and issues an override I/O.
+ * Since this is a dedup block, the override I/O will determine if the
+ * block is already in the DDT. If so, then it will replace the io_bp
+ * with the bp from the DDT and allow the I/O to finish. When the I/O
+ * reaches the done callback, dbuf_write_override_done, it will
+ * check to see if the io_bp and io_bp_override are identical.
+ * If they are not, then it indicates that the bp was replaced with
+ * the bp in the DDT and the override bp is freed. This allows
+ * us to arrive here with a reference on a block that is being
+ * freed. So if we have an I/O in progress, or a reference to
+ * this hdr, then we don't destroy the hdr.
+ */
+ if (!HDR_HAS_L1HDR(hdr) || (!HDR_IO_IN_PROGRESS(hdr) &&
+ refcount_is_zero(&hdr->b_l1hdr.b_refcnt))) {
+ arc_change_state(arc_anon, hdr, hash_lock);
+ arc_hdr_destroy(hdr);
mutex_exit(hash_lock);
- }
-
-}
-
-/*
- * Clear the user eviction callback set by arc_set_callback(), first calling
- * it if it exists. Because the presence of a callback keeps an arc_buf cached
- * clearing the callback may result in the arc_buf being destroyed. However,
- * it will not result in the *last* arc_buf being destroyed, hence the data
- * will remain cached in the ARC. We make a copy of the arc buffer here so
- * that we can process the callback without holding any locks.
- *
- * It's possible that the callback is already in the process of being cleared
- * by another thread. In this case we can not clear the callback.
- *
- * Returns B_TRUE if the callback was successfully called and cleared.
- */
-boolean_t
-arc_clear_callback(arc_buf_t *buf)
-{
- arc_buf_hdr_t *hdr;
- kmutex_t *hash_lock;
- arc_evict_func_t *efunc = buf->b_efunc;
- void *private = buf->b_private;
-
- mutex_enter(&buf->b_evict_lock);
- hdr = buf->b_hdr;
- if (hdr == NULL) {
- /*
- * We are in arc_do_user_evicts().
- */
- ASSERT(buf->b_data == NULL);
- mutex_exit(&buf->b_evict_lock);
- return (B_FALSE);
- } else if (buf->b_data == NULL) {
- /*
- * We are on the eviction list; process this buffer now
- * but let arc_do_user_evicts() do the reaping.
- */
- buf->b_efunc = NULL;
- mutex_exit(&buf->b_evict_lock);
- VERIFY0(efunc(private));
- return (B_TRUE);
- }
- hash_lock = HDR_LOCK(hdr);
- mutex_enter(hash_lock);
- hdr = buf->b_hdr;
- ASSERT3P(hash_lock, ==, HDR_LOCK(hdr));
-
- ASSERT3U(refcount_count(&hdr->b_l1hdr.b_refcnt), <,
- hdr->b_l1hdr.b_datacnt);
- ASSERT(hdr->b_l1hdr.b_state == arc_mru ||
- hdr->b_l1hdr.b_state == arc_mfu);
-
- buf->b_efunc = NULL;
- buf->b_private = NULL;
-
- if (hdr->b_l1hdr.b_datacnt > 1) {
- mutex_exit(&buf->b_evict_lock);
- arc_buf_destroy(buf, TRUE);
} else {
- ASSERT(buf == hdr->b_l1hdr.b_buf);
- hdr->b_flags |= ARC_FLAG_BUF_AVAILABLE;
- mutex_exit(&buf->b_evict_lock);
+ mutex_exit(hash_lock);
}
- mutex_exit(hash_lock);
- VERIFY0(efunc(private));
- return (B_TRUE);
}
/*
ASSERT(!HDR_IO_IN_PROGRESS(hdr));
ASSERT(!HDR_IN_HASH_TABLE(hdr));
ASSERT(!HDR_HAS_L2HDR(hdr));
- ASSERT(BUF_EMPTY(hdr));
+ ASSERT(HDR_EMPTY(hdr));
- ASSERT3U(hdr->b_l1hdr.b_datacnt, ==, 1);
+ ASSERT3U(hdr->b_l1hdr.b_bufcnt, ==, 1);
ASSERT3S(refcount_count(&hdr->b_l1hdr.b_refcnt), ==, 1);
ASSERT(!list_link_active(&hdr->b_l1hdr.b_arc_node));
- ASSERT3P(buf->b_efunc, ==, NULL);
- ASSERT3P(buf->b_private, ==, NULL);
-
hdr->b_l1hdr.b_arc_access = 0;
+
+ /*
+ * If the buf is being overridden then it may already
+ * have a hdr that is not empty.
+ */
+ buf_discard_identity(hdr);
arc_buf_thaw(buf);
return;
ASSERT3P(state, !=, arc_anon);
/* this buffer is not on any list */
- ASSERT(refcount_count(&hdr->b_l1hdr.b_refcnt) > 0);
+ ASSERT3S(refcount_count(&hdr->b_l1hdr.b_refcnt), >, 0);
if (HDR_HAS_L2HDR(hdr)) {
- ARCSTAT_INCR(arcstat_l2_asize, -hdr->b_l2hdr.b_asize);
- ARCSTAT_INCR(arcstat_l2_size, -hdr->b_size);
-
mutex_enter(&hdr->b_l2hdr.b_dev->l2ad_mtx);
- list_remove(&hdr->b_l2hdr.b_dev->l2ad_buflist, hdr);
/*
- * We don't want to leak the b_tmp_cdata buffer that was
- * allocated in l2arc_write_buffers()
+ * We have to recheck this conditional again now that
+ * we're holding the l2ad_mtx to prevent a race with
+ * another thread which might be concurrently calling
+ * l2arc_evict(). In that case, l2arc_evict() might have
+ * destroyed the header's L2 portion as we were waiting
+ * to acquire the l2ad_mtx.
*/
- arc_buf_l2_cdata_free(hdr);
+ if (HDR_HAS_L2HDR(hdr))
+ arc_hdr_l2hdr_destroy(hdr);
mutex_exit(&hdr->b_l2hdr.b_dev->l2ad_mtx);
-
- hdr->b_flags &= ~ARC_FLAG_HAS_L2HDR;
}
/*
* Do we have more than one buf?
*/
- if (hdr->b_l1hdr.b_datacnt > 1) {
+ if (hdr->b_l1hdr.b_bufcnt > 1) {
arc_buf_hdr_t *nhdr;
- arc_buf_t **bufp;
- uint64_t blksz = hdr->b_size;
uint64_t spa = hdr->b_spa;
+ uint64_t psize = HDR_GET_PSIZE(hdr);
+ uint64_t lsize = HDR_GET_LSIZE(hdr);
+ boolean_t protected = HDR_PROTECTED(hdr);
+ enum zio_compress compress = arc_hdr_get_compress(hdr);
arc_buf_contents_t type = arc_buf_type(hdr);
- uint32_t flags = hdr->b_flags;
+ VERIFY3U(hdr->b_type, ==, type);
ASSERT(hdr->b_l1hdr.b_buf != buf || buf->b_next != NULL);
+ (void) remove_reference(hdr, hash_lock, tag);
+
+ if (arc_buf_is_shared(buf) && !ARC_BUF_COMPRESSED(buf)) {
+ ASSERT3P(hdr->b_l1hdr.b_buf, !=, buf);
+ ASSERT(ARC_BUF_LAST(buf));
+ }
+
/*
* Pull the data off of this hdr and attach it to
- * a new anonymous hdr.
+ * a new anonymous hdr. Also find the last buffer
+ * in the hdr's buffer list.
*/
- (void) remove_reference(hdr, hash_lock, tag);
- bufp = &hdr->b_l1hdr.b_buf;
- while (*bufp != buf)
- bufp = &(*bufp)->b_next;
- *bufp = buf->b_next;
- buf->b_next = NULL;
+ arc_buf_t *lastbuf = arc_buf_remove(hdr, buf);
+ ASSERT3P(lastbuf, !=, NULL);
+
+ /*
+ * If the current arc_buf_t and the hdr are sharing their data
+ * buffer, then we must stop sharing that block.
+ */
+ if (arc_buf_is_shared(buf)) {
+ ASSERT3P(hdr->b_l1hdr.b_buf, !=, buf);
+ VERIFY(!arc_buf_is_shared(lastbuf));
+
+ /*
+ * First, sever the block sharing relationship between
+ * buf and the arc_buf_hdr_t.
+ */
+ arc_unshare_buf(hdr, buf);
+
+ /*
+ * Now we need to recreate the hdr's b_pabd. Since we
+ * have lastbuf handy, we try to share with it, but if
+ * we can't then we allocate a new b_pabd and copy the
+ * data from buf into it.
+ */
+ if (arc_can_share(hdr, lastbuf)) {
+ arc_share_buf(hdr, lastbuf);
+ } else {
+ arc_hdr_alloc_abd(hdr, B_FALSE);
+ abd_copy_from_buf(hdr->b_l1hdr.b_pabd,
+ buf->b_data, psize);
+ }
+ VERIFY3P(lastbuf->b_data, !=, NULL);
+ } else if (HDR_SHARED_DATA(hdr)) {
+ /*
+ * Uncompressed shared buffers are always at the end
+ * of the list. Compressed buffers don't have the
+ * same requirements. This makes it hard to
+ * simply assert that the lastbuf is shared so
+ * we rely on the hdr's compression flags to determine
+ * if we have a compressed, shared buffer.
+ */
+ ASSERT(arc_buf_is_shared(lastbuf) ||
+ arc_hdr_get_compress(hdr) != ZIO_COMPRESS_OFF);
+ ASSERT(!ARC_BUF_SHARED(buf));
+ }
+ ASSERT(hdr->b_l1hdr.b_pabd != NULL || HDR_HAS_RABD(hdr));
ASSERT3P(state, !=, arc_l2c_only);
- ASSERT3U(state->arcs_size, >=, hdr->b_size);
- atomic_add_64(&state->arcs_size, -hdr->b_size);
- if (refcount_is_zero(&hdr->b_l1hdr.b_refcnt)) {
- uint64_t *size;
+ (void) refcount_remove_many(&state->arcs_size,
+ arc_buf_size(buf), buf);
+
+ if (refcount_is_zero(&hdr->b_l1hdr.b_refcnt)) {
ASSERT3P(state, !=, arc_l2c_only);
- size = &state->arcs_lsize[type];
- ASSERT3U(*size, >=, hdr->b_size);
- atomic_add_64(size, -hdr->b_size);
+ (void) refcount_remove_many(&state->arcs_esize[type],
+ arc_buf_size(buf), buf);
}
- /*
- * We're releasing a duplicate user data buffer, update
- * our statistics accordingly.
- */
- if (HDR_ISTYPE_DATA(hdr)) {
- ARCSTAT_BUMPDOWN(arcstat_duplicate_buffers);
- ARCSTAT_INCR(arcstat_duplicate_buffers_size,
- -hdr->b_size);
- }
- hdr->b_l1hdr.b_datacnt -= 1;
+ hdr->b_l1hdr.b_bufcnt -= 1;
+ if (ARC_BUF_ENCRYPTED(buf))
+ hdr->b_crypt_hdr.b_ebufcnt -= 1;
+
arc_cksum_verify(buf);
arc_buf_unwatch(buf);
+ /* if this is the last uncompressed buf free the checksum */
+ if (!arc_hdr_has_uncompressed_buf(hdr))
+ arc_cksum_free(hdr);
+
mutex_exit(hash_lock);
- nhdr = kmem_cache_alloc(hdr_full_cache, KM_PUSHPAGE);
- nhdr->b_size = blksz;
- nhdr->b_spa = spa;
+ /*
+ * Allocate a new hdr. The new hdr will contain a b_pabd
+ * buffer which will be freed in arc_write().
+ */
+ nhdr = arc_hdr_alloc(spa, psize, lsize, protected,
+ compress, type, HDR_HAS_RABD(hdr));
+ ASSERT3P(nhdr->b_l1hdr.b_buf, ==, NULL);
+ ASSERT0(nhdr->b_l1hdr.b_bufcnt);
+ ASSERT0(refcount_count(&nhdr->b_l1hdr.b_refcnt));
+ VERIFY3U(nhdr->b_type, ==, type);
+ ASSERT(!HDR_SHARED_DATA(nhdr));
+ nhdr->b_l1hdr.b_buf = buf;
+ nhdr->b_l1hdr.b_bufcnt = 1;
+ if (ARC_BUF_ENCRYPTED(buf))
+ nhdr->b_crypt_hdr.b_ebufcnt = 1;
nhdr->b_l1hdr.b_mru_hits = 0;
nhdr->b_l1hdr.b_mru_ghost_hits = 0;
nhdr->b_l1hdr.b_mfu_hits = 0;
nhdr->b_l1hdr.b_mfu_ghost_hits = 0;
nhdr->b_l1hdr.b_l2_hits = 0;
- nhdr->b_flags = flags & ARC_FLAG_L2_WRITING;
- nhdr->b_flags |= arc_bufc_to_flags(type);
- nhdr->b_flags |= ARC_FLAG_HAS_L1HDR;
-
- nhdr->b_l1hdr.b_buf = buf;
- nhdr->b_l1hdr.b_datacnt = 1;
- nhdr->b_l1hdr.b_state = arc_anon;
- nhdr->b_l1hdr.b_arc_access = 0;
- nhdr->b_l1hdr.b_tmp_cdata = NULL;
- nhdr->b_freeze_cksum = NULL;
-
(void) refcount_add(&nhdr->b_l1hdr.b_refcnt, tag);
buf->b_hdr = nhdr;
+
mutex_exit(&buf->b_evict_lock);
- atomic_add_64(&arc_anon->arcs_size, blksz);
+ (void) refcount_add_many(&arc_anon->arcs_size,
+ HDR_GET_LSIZE(nhdr), buf);
} else {
mutex_exit(&buf->b_evict_lock);
ASSERT(refcount_count(&hdr->b_l1hdr.b_refcnt) == 1);
hdr->b_l1hdr.b_l2_hits = 0;
arc_change_state(arc_anon, hdr, hash_lock);
hdr->b_l1hdr.b_arc_access = 0;
- mutex_exit(hash_lock);
+ mutex_exit(hash_lock);
buf_discard_identity(hdr);
arc_buf_thaw(buf);
}
- buf->b_efunc = NULL;
- buf->b_private = NULL;
}
int
arc_write_callback_t *callback = zio->io_private;
arc_buf_t *buf = callback->awcb_buf;
arc_buf_hdr_t *hdr = buf->b_hdr;
+ blkptr_t *bp = zio->io_bp;
+ uint64_t psize = BP_IS_HOLE(bp) ? 0 : BP_GET_PSIZE(bp);
+ enum zio_compress compress;
+ fstrans_cookie_t cookie = spl_fstrans_mark();
ASSERT(HDR_HAS_L1HDR(hdr));
ASSERT(!refcount_is_zero(&buf->b_hdr->b_l1hdr.b_refcnt));
- ASSERT(hdr->b_l1hdr.b_datacnt > 0);
+ ASSERT(hdr->b_l1hdr.b_bufcnt > 0);
+
+ /*
+ * If we're reexecuting this zio because the pool suspended, then
+ * cleanup any state that was previously set the first time the
+ * callback was invoked.
+ */
+ if (zio->io_flags & ZIO_FLAG_REEXECUTED) {
+ arc_cksum_free(hdr);
+ arc_buf_unwatch(buf);
+ if (hdr->b_l1hdr.b_pabd != NULL) {
+ if (arc_buf_is_shared(buf)) {
+ arc_unshare_buf(hdr, buf);
+ } else {
+ arc_hdr_free_abd(hdr, B_FALSE);
+ }
+ }
+
+ if (HDR_HAS_RABD(hdr))
+ arc_hdr_free_abd(hdr, B_TRUE);
+ }
+ ASSERT3P(hdr->b_l1hdr.b_pabd, ==, NULL);
+ ASSERT(!HDR_HAS_RABD(hdr));
+ ASSERT(!HDR_SHARED_DATA(hdr));
+ ASSERT(!arc_buf_is_shared(buf));
+
callback->awcb_ready(zio, buf, callback->awcb_private);
+ if (HDR_IO_IN_PROGRESS(hdr))
+ ASSERT(zio->io_flags & ZIO_FLAG_REEXECUTED);
+
+ arc_hdr_set_flags(hdr, ARC_FLAG_IO_IN_PROGRESS);
+
+ if (BP_IS_PROTECTED(bp) != !!HDR_PROTECTED(hdr))
+ hdr = arc_hdr_realloc_crypt(hdr, BP_IS_PROTECTED(bp));
+
+ if (BP_IS_PROTECTED(bp)) {
+ /* ZIL blocks are written through zio_rewrite */
+ ASSERT3U(BP_GET_TYPE(bp), !=, DMU_OT_INTENT_LOG);
+ ASSERT(HDR_PROTECTED(hdr));
+
+ hdr->b_crypt_hdr.b_ot = BP_GET_TYPE(bp);
+ hdr->b_crypt_hdr.b_dsobj = zio->io_bookmark.zb_objset;
+ zio_crypt_decode_params_bp(bp, hdr->b_crypt_hdr.b_salt,
+ hdr->b_crypt_hdr.b_iv);
+ zio_crypt_decode_mac_bp(bp, hdr->b_crypt_hdr.b_mac);
+ }
+
+ /*
+ * If this block was written for raw encryption but the zio layer
+ * ended up only authenticating it, adjust the buffer flags now.
+ */
+ if (BP_IS_AUTHENTICATED(bp) && ARC_BUF_ENCRYPTED(buf)) {
+ arc_hdr_set_flags(hdr, ARC_FLAG_NOAUTH);
+ buf->b_flags &= ~ARC_BUF_FLAG_ENCRYPTED;
+ if (BP_GET_COMPRESS(bp) == ZIO_COMPRESS_OFF)
+ buf->b_flags &= ~ARC_BUF_FLAG_COMPRESSED;
+ }
+
+ /* this must be done after the buffer flags are adjusted */
+ arc_cksum_compute(buf);
+
+ if (BP_IS_HOLE(bp) || BP_IS_EMBEDDED(bp)) {
+ compress = ZIO_COMPRESS_OFF;
+ } else {
+ ASSERT3U(HDR_GET_LSIZE(hdr), ==, BP_GET_LSIZE(bp));
+ compress = BP_GET_COMPRESS(bp);
+ }
+ HDR_SET_PSIZE(hdr, psize);
+ arc_hdr_set_compress(hdr, compress);
+
+ if (zio->io_error != 0 || psize == 0)
+ goto out;
+
/*
- * If the IO is already in progress, then this is a re-write
- * attempt, so we need to thaw and re-compute the cksum.
- * It is the responsibility of the callback to handle the
- * accounting for any re-write attempt.
+ * Fill the hdr with data. If the buffer is encrypted we have no choice
+ * but to copy the data into b_radb. If the hdr is compressed, the data
+ * we want is available from the zio, otherwise we can take it from
+ * the buf.
+ *
+ * We might be able to share the buf's data with the hdr here. However,
+ * doing so would cause the ARC to be full of linear ABDs if we write a
+ * lot of shareable data. As a compromise, we check whether scattered
+ * ABDs are allowed, and assume that if they are then the user wants
+ * the ARC to be primarily filled with them regardless of the data being
+ * written. Therefore, if they're allowed then we allocate one and copy
+ * the data into it; otherwise, we share the data directly if we can.
*/
- if (HDR_IO_IN_PROGRESS(hdr)) {
- mutex_enter(&hdr->b_l1hdr.b_freeze_lock);
- if (hdr->b_freeze_cksum != NULL) {
- kmem_free(hdr->b_freeze_cksum, sizeof (zio_cksum_t));
- hdr->b_freeze_cksum = NULL;
+ if (ARC_BUF_ENCRYPTED(buf)) {
+ ASSERT3U(psize, >, 0);
+ ASSERT(ARC_BUF_COMPRESSED(buf));
+ arc_hdr_alloc_abd(hdr, B_TRUE);
+ abd_copy(hdr->b_crypt_hdr.b_rabd, zio->io_abd, psize);
+ } else if (zfs_abd_scatter_enabled || !arc_can_share(hdr, buf)) {
+ /*
+ * Ideally, we would always copy the io_abd into b_pabd, but the
+ * user may have disabled compressed ARC, thus we must check the
+ * hdr's compression setting rather than the io_bp's.
+ */
+ if (BP_IS_ENCRYPTED(bp)) {
+ ASSERT3U(psize, >, 0);
+ arc_hdr_alloc_abd(hdr, B_TRUE);
+ abd_copy(hdr->b_crypt_hdr.b_rabd, zio->io_abd, psize);
+ } else if (arc_hdr_get_compress(hdr) != ZIO_COMPRESS_OFF &&
+ !ARC_BUF_COMPRESSED(buf)) {
+ ASSERT3U(psize, >, 0);
+ arc_hdr_alloc_abd(hdr, B_FALSE);
+ abd_copy(hdr->b_l1hdr.b_pabd, zio->io_abd, psize);
+ } else {
+ ASSERT3U(zio->io_orig_size, ==, arc_hdr_size(hdr));
+ arc_hdr_alloc_abd(hdr, B_FALSE);
+ abd_copy_from_buf(hdr->b_l1hdr.b_pabd, buf->b_data,
+ arc_buf_size(buf));
}
- mutex_exit(&hdr->b_l1hdr.b_freeze_lock);
+ } else {
+ ASSERT3P(buf->b_data, ==, abd_to_buf(zio->io_orig_abd));
+ ASSERT3U(zio->io_orig_size, ==, arc_buf_size(buf));
+ ASSERT3U(hdr->b_l1hdr.b_bufcnt, ==, 1);
+
+ arc_share_buf(hdr, buf);
}
- arc_cksum_compute(buf, B_FALSE);
- hdr->b_flags |= ARC_FLAG_IO_IN_PROGRESS;
+
+out:
+ arc_hdr_verify(hdr, bp);
+ spl_fstrans_unmark(cookie);
+}
+
+static void
+arc_write_children_ready(zio_t *zio)
+{
+ arc_write_callback_t *callback = zio->io_private;
+ arc_buf_t *buf = callback->awcb_buf;
+
+ callback->awcb_children_ready(zio, buf, callback->awcb_private);
}
/*
arc_buf_t *buf = callback->awcb_buf;
arc_buf_hdr_t *hdr = buf->b_hdr;
- ASSERT(hdr->b_l1hdr.b_acb == NULL);
+ ASSERT3P(hdr->b_l1hdr.b_acb, ==, NULL);
if (zio->io_error == 0) {
+ arc_hdr_verify(hdr, zio->io_bp);
+
if (BP_IS_HOLE(zio->io_bp) || BP_IS_EMBEDDED(zio->io_bp)) {
buf_discard_identity(hdr);
} else {
hdr->b_birth = BP_PHYSICAL_BIRTH(zio->io_bp);
}
} else {
- ASSERT(BUF_EMPTY(hdr));
+ ASSERT(HDR_EMPTY(hdr));
}
/*
* dva/birth/checksum. The buffer must therefore remain anonymous
* (and uncached).
*/
- if (!BUF_EMPTY(hdr)) {
+ if (!HDR_EMPTY(hdr)) {
arc_buf_hdr_t *exists;
kmutex_t *hash_lock;
- ASSERT(zio->io_error == 0);
+ ASSERT3U(zio->io_error, ==, 0);
arc_cksum_verify(buf);
(void *)hdr, (void *)exists);
} else {
/* Dedup */
- ASSERT(hdr->b_l1hdr.b_datacnt == 1);
+ ASSERT(hdr->b_l1hdr.b_bufcnt == 1);
ASSERT(hdr->b_l1hdr.b_state == arc_anon);
ASSERT(BP_GET_DEDUP(zio->io_bp));
ASSERT(BP_GET_LEVEL(zio->io_bp) == 0);
}
}
- hdr->b_flags &= ~ARC_FLAG_IO_IN_PROGRESS;
+ arc_hdr_clear_flags(hdr, ARC_FLAG_IO_IN_PROGRESS);
/* if it's not anon, we are doing a scrub */
if (exists == NULL && hdr->b_l1hdr.b_state == arc_anon)
arc_access(hdr, hash_lock);
mutex_exit(hash_lock);
} else {
- hdr->b_flags &= ~ARC_FLAG_IO_IN_PROGRESS;
+ arc_hdr_clear_flags(hdr, ARC_FLAG_IO_IN_PROGRESS);
}
ASSERT(!refcount_is_zero(&hdr->b_l1hdr.b_refcnt));
callback->awcb_done(zio, buf, callback->awcb_private);
+ abd_put(zio->io_abd);
kmem_free(callback, sizeof (arc_write_callback_t));
}
zio_t *
arc_write(zio_t *pio, spa_t *spa, uint64_t txg,
- blkptr_t *bp, arc_buf_t *buf, boolean_t l2arc, boolean_t l2arc_compress,
- const zio_prop_t *zp, arc_done_func_t *ready, arc_done_func_t *physdone,
- arc_done_func_t *done, void *private, zio_priority_t priority,
+ blkptr_t *bp, arc_buf_t *buf, boolean_t l2arc,
+ const zio_prop_t *zp, arc_write_done_func_t *ready,
+ arc_write_done_func_t *children_ready, arc_write_done_func_t *physdone,
+ arc_write_done_func_t *done, void *private, zio_priority_t priority,
int zio_flags, const zbookmark_phys_t *zb)
{
arc_buf_hdr_t *hdr = buf->b_hdr;
arc_write_callback_t *callback;
zio_t *zio;
+ zio_prop_t localprop = *zp;
- ASSERT(ready != NULL);
- ASSERT(done != NULL);
+ ASSERT3P(ready, !=, NULL);
+ ASSERT3P(done, !=, NULL);
ASSERT(!HDR_IO_ERROR(hdr));
ASSERT(!HDR_IO_IN_PROGRESS(hdr));
- ASSERT(hdr->b_l1hdr.b_acb == NULL);
- ASSERT(hdr->b_l1hdr.b_datacnt > 0);
+ ASSERT3P(hdr->b_l1hdr.b_acb, ==, NULL);
+ ASSERT3U(hdr->b_l1hdr.b_bufcnt, >, 0);
if (l2arc)
- hdr->b_flags |= ARC_FLAG_L2CACHE;
- if (l2arc_compress)
- hdr->b_flags |= ARC_FLAG_L2COMPRESS;
+ arc_hdr_set_flags(hdr, ARC_FLAG_L2CACHE);
+
+ if (ARC_BUF_ENCRYPTED(buf)) {
+ ASSERT(ARC_BUF_COMPRESSED(buf));
+ localprop.zp_encrypt = B_TRUE;
+ localprop.zp_compress = HDR_GET_COMPRESS(hdr);
+ localprop.zp_byteorder =
+ (hdr->b_l1hdr.b_byteswap == DMU_BSWAP_NUMFUNCS) ?
+ ZFS_HOST_BYTEORDER : !ZFS_HOST_BYTEORDER;
+ bcopy(hdr->b_crypt_hdr.b_salt, localprop.zp_salt,
+ ZIO_DATA_SALT_LEN);
+ bcopy(hdr->b_crypt_hdr.b_iv, localprop.zp_iv,
+ ZIO_DATA_IV_LEN);
+ bcopy(hdr->b_crypt_hdr.b_mac, localprop.zp_mac,
+ ZIO_DATA_MAC_LEN);
+ if (DMU_OT_IS_ENCRYPTED(localprop.zp_type)) {
+ localprop.zp_nopwrite = B_FALSE;
+ localprop.zp_copies =
+ MIN(localprop.zp_copies, SPA_DVAS_PER_BP - 1);
+ }
+ zio_flags |= ZIO_FLAG_RAW;
+ } else if (ARC_BUF_COMPRESSED(buf)) {
+ ASSERT3U(HDR_GET_LSIZE(hdr), !=, arc_buf_size(buf));
+ localprop.zp_compress = HDR_GET_COMPRESS(hdr);
+ zio_flags |= ZIO_FLAG_RAW_COMPRESS;
+ }
callback = kmem_zalloc(sizeof (arc_write_callback_t), KM_SLEEP);
callback->awcb_ready = ready;
+ callback->awcb_children_ready = children_ready;
callback->awcb_physdone = physdone;
callback->awcb_done = done;
callback->awcb_private = private;
callback->awcb_buf = buf;
- zio = zio_write(pio, spa, txg, bp, buf->b_data, hdr->b_size, zp,
- arc_write_ready, arc_write_physdone, arc_write_done, callback,
+ /*
+ * The hdr's b_pabd is now stale, free it now. A new data block
+ * will be allocated when the zio pipeline calls arc_write_ready().
+ */
+ if (hdr->b_l1hdr.b_pabd != NULL) {
+ /*
+ * If the buf is currently sharing the data block with
+ * the hdr then we need to break that relationship here.
+ * The hdr will remain with a NULL data pointer and the
+ * buf will take sole ownership of the block.
+ */
+ if (arc_buf_is_shared(buf)) {
+ arc_unshare_buf(hdr, buf);
+ } else {
+ arc_hdr_free_abd(hdr, B_FALSE);
+ }
+ VERIFY3P(buf->b_data, !=, NULL);
+ }
+
+ if (HDR_HAS_RABD(hdr))
+ arc_hdr_free_abd(hdr, B_TRUE);
+
+ arc_hdr_set_compress(hdr, ZIO_COMPRESS_OFF);
+
+ ASSERT(!arc_buf_is_shared(buf));
+ ASSERT3P(hdr->b_l1hdr.b_pabd, ==, NULL);
+
+ zio = zio_write(pio, spa, txg, bp,
+ abd_get_from_buf(buf->b_data, HDR_GET_LSIZE(hdr)),
+ HDR_GET_LSIZE(hdr), arc_buf_size(buf), &localprop, arc_write_ready,
+ (children_ready != NULL) ? arc_write_children_ready : NULL,
+ arc_write_physdone, arc_write_done, callback,
priority, zio_flags, zb);
return (zio);
arc_memory_throttle(uint64_t reserve, uint64_t txg)
{
#ifdef _KERNEL
- if (zfs_arc_memory_throttle_disable)
+ uint64_t available_memory = arc_free_memory();
+ static uint64_t page_load = 0;
+ static uint64_t last_txg = 0;
+
+#if defined(_ILP32)
+ available_memory =
+ MIN(available_memory, vmem_size(heap_arena, VMEM_FREE));
+#endif
+
+ if (available_memory > arc_all_memory() * arc_lotsfree_percent / 100)
return (0);
- if (freemem <= physmem * arc_lotsfree_percent / 100) {
+ if (txg > last_txg) {
+ last_txg = txg;
+ page_load = 0;
+ }
+ /*
+ * If we are in pageout, we know that memory is already tight,
+ * the arc is already going to be evicting, so we just want to
+ * continue to let page writes occur as quickly as possible.
+ */
+ if (current_is_kswapd()) {
+ if (page_load > MAX(arc_sys_free / 4, available_memory) / 4) {
+ DMU_TX_STAT_BUMP(dmu_tx_memory_reclaim);
+ return (SET_ERROR(ERESTART));
+ }
+ /* Note: reserve is inflated, so we deflate */
+ page_load += reserve / 8;
+ return (0);
+ } else if (page_load > 0 && arc_reclaim_needed()) {
+ /* memory is low, delay before restarting */
ARCSTAT_INCR(arcstat_memory_throttle_count, 1);
DMU_TX_STAT_BUMP(dmu_tx_memory_reclaim);
return (SET_ERROR(EAGAIN));
}
+ page_load = 0;
#endif
return (0);
}
int error;
uint64_t anon_size;
- if (reserve > arc_c/4 && !arc_no_grow)
+ if (!arc_no_grow &&
+ reserve > arc_c/4 &&
+ reserve * 4 > (2ULL << SPA_MAXBLOCKSHIFT))
arc_c = MIN(arc_c_max, reserve * 4);
/*
* network delays from blocking transactions that are ready to be
* assigned to a txg.
*/
- anon_size = MAX((int64_t)(arc_anon->arcs_size - arc_loaned_bytes), 0);
+
+ /* assert that it has not wrapped around */
+ ASSERT3S(atomic_add_64_nv(&arc_loaned_bytes, 0), >=, 0);
+
+ anon_size = MAX((int64_t)(refcount_count(&arc_anon->arcs_size) -
+ arc_loaned_bytes), 0);
/*
* Writes will, almost always, require additional memory allocations
if (reserve + arc_tempreserve + anon_size > arc_c / 2 &&
anon_size > arc_c / 4) {
+ uint64_t meta_esize =
+ refcount_count(&arc_anon->arcs_esize[ARC_BUFC_METADATA]);
+ uint64_t data_esize =
+ refcount_count(&arc_anon->arcs_esize[ARC_BUFC_DATA]);
dprintf("failing, arc_tempreserve=%lluK anon_meta=%lluK "
"anon_data=%lluK tempreserve=%lluK arc_c=%lluK\n",
- arc_tempreserve>>10,
- arc_anon->arcs_lsize[ARC_BUFC_METADATA]>>10,
- arc_anon->arcs_lsize[ARC_BUFC_DATA]>>10,
- reserve>>10, arc_c>>10);
+ arc_tempreserve >> 10, meta_esize >> 10,
+ data_esize >> 10, reserve >> 10, arc_c >> 10);
DMU_TX_STAT_BUMP(dmu_tx_dirty_throttle);
return (SET_ERROR(ERESTART));
}
arc_kstat_update_state(arc_state_t *state, kstat_named_t *size,
kstat_named_t *evict_data, kstat_named_t *evict_metadata)
{
- size->value.ui64 = state->arcs_size;
- evict_data->value.ui64 = state->arcs_lsize[ARC_BUFC_DATA];
- evict_metadata->value.ui64 = state->arcs_lsize[ARC_BUFC_METADATA];
+ size->value.ui64 = refcount_count(&state->arcs_size);
+ evict_data->value.ui64 =
+ refcount_count(&state->arcs_esize[ARC_BUFC_DATA]);
+ evict_metadata->value.ui64 =
+ refcount_count(&state->arcs_esize[ARC_BUFC_METADATA]);
}
static int
} else {
arc_kstat_update_state(arc_anon,
&as->arcstat_anon_size,
- &as->arcstat_anon_evict_data,
- &as->arcstat_anon_evict_metadata);
+ &as->arcstat_anon_evictable_data,
+ &as->arcstat_anon_evictable_metadata);
arc_kstat_update_state(arc_mru,
&as->arcstat_mru_size,
- &as->arcstat_mru_evict_data,
- &as->arcstat_mru_evict_metadata);
+ &as->arcstat_mru_evictable_data,
+ &as->arcstat_mru_evictable_metadata);
arc_kstat_update_state(arc_mru_ghost,
&as->arcstat_mru_ghost_size,
- &as->arcstat_mru_ghost_evict_data,
- &as->arcstat_mru_ghost_evict_metadata);
+ &as->arcstat_mru_ghost_evictable_data,
+ &as->arcstat_mru_ghost_evictable_metadata);
arc_kstat_update_state(arc_mfu,
&as->arcstat_mfu_size,
- &as->arcstat_mfu_evict_data,
- &as->arcstat_mfu_evict_metadata);
+ &as->arcstat_mfu_evictable_data,
+ &as->arcstat_mfu_evictable_metadata);
arc_kstat_update_state(arc_mfu_ghost,
&as->arcstat_mfu_ghost_size,
- &as->arcstat_mfu_ghost_evict_data,
- &as->arcstat_mfu_ghost_evict_metadata);
+ &as->arcstat_mfu_ghost_evictable_data,
+ &as->arcstat_mfu_ghost_evictable_metadata);
+
+ as->arcstat_memory_all_bytes.value.ui64 =
+ arc_all_memory();
+ as->arcstat_memory_free_bytes.value.ui64 =
+ arc_free_memory();
+ as->arcstat_memory_available_bytes.value.i64 =
+ arc_available_memory();
}
return (0);
* numbers using buf_hash below. So, as an added precaution,
* let's make sure we never add empty buffers to the arc lists.
*/
- ASSERT(!BUF_EMPTY(hdr));
+ ASSERT(!HDR_EMPTY(hdr));
/*
* The assumption here, is the hash value for a given
multilist_get_num_sublists(ml));
}
+/*
+ * Called during module initialization and periodically thereafter to
+ * apply reasonable changes to the exposed performance tunings. Non-zero
+ * zfs_* values which differ from the currently set values will be applied.
+ */
+static void
+arc_tuning_update(void)
+{
+ uint64_t allmem = arc_all_memory();
+ unsigned long limit;
+
+ /* Valid range: 64M - <all physical memory> */
+ if ((zfs_arc_max) && (zfs_arc_max != arc_c_max) &&
+ (zfs_arc_max > 64 << 20) && (zfs_arc_max < allmem) &&
+ (zfs_arc_max > arc_c_min)) {
+ arc_c_max = zfs_arc_max;
+ arc_c = arc_c_max;
+ arc_p = (arc_c >> 1);
+ if (arc_meta_limit > arc_c_max)
+ arc_meta_limit = arc_c_max;
+ if (arc_dnode_limit > arc_meta_limit)
+ arc_dnode_limit = arc_meta_limit;
+ }
+
+ /* Valid range: 32M - <arc_c_max> */
+ if ((zfs_arc_min) && (zfs_arc_min != arc_c_min) &&
+ (zfs_arc_min >= 2ULL << SPA_MAXBLOCKSHIFT) &&
+ (zfs_arc_min <= arc_c_max)) {
+ arc_c_min = zfs_arc_min;
+ arc_c = MAX(arc_c, arc_c_min);
+ }
+
+ /* Valid range: 16M - <arc_c_max> */
+ if ((zfs_arc_meta_min) && (zfs_arc_meta_min != arc_meta_min) &&
+ (zfs_arc_meta_min >= 1ULL << SPA_MAXBLOCKSHIFT) &&
+ (zfs_arc_meta_min <= arc_c_max)) {
+ arc_meta_min = zfs_arc_meta_min;
+ if (arc_meta_limit < arc_meta_min)
+ arc_meta_limit = arc_meta_min;
+ if (arc_dnode_limit < arc_meta_min)
+ arc_dnode_limit = arc_meta_min;
+ }
+
+ /* Valid range: <arc_meta_min> - <arc_c_max> */
+ limit = zfs_arc_meta_limit ? zfs_arc_meta_limit :
+ MIN(zfs_arc_meta_limit_percent, 100) * arc_c_max / 100;
+ if ((limit != arc_meta_limit) &&
+ (limit >= arc_meta_min) &&
+ (limit <= arc_c_max))
+ arc_meta_limit = limit;
+
+ /* Valid range: <arc_meta_min> - <arc_meta_limit> */
+ limit = zfs_arc_dnode_limit ? zfs_arc_dnode_limit :
+ MIN(zfs_arc_dnode_limit_percent, 100) * arc_meta_limit / 100;
+ if ((limit != arc_dnode_limit) &&
+ (limit >= arc_meta_min) &&
+ (limit <= arc_meta_limit))
+ arc_dnode_limit = limit;
+
+ /* Valid range: 1 - N */
+ if (zfs_arc_grow_retry)
+ arc_grow_retry = zfs_arc_grow_retry;
+
+ /* Valid range: 1 - N */
+ if (zfs_arc_shrink_shift) {
+ arc_shrink_shift = zfs_arc_shrink_shift;
+ arc_no_grow_shift = MIN(arc_no_grow_shift, arc_shrink_shift -1);
+ }
+
+ /* Valid range: 1 - N */
+ if (zfs_arc_p_min_shift)
+ arc_p_min_shift = zfs_arc_p_min_shift;
+
+ /* Valid range: 1 - N ticks */
+ if (zfs_arc_min_prefetch_lifespan)
+ arc_min_prefetch_lifespan = zfs_arc_min_prefetch_lifespan;
+
+ /* Valid range: 0 - 100 */
+ if ((zfs_arc_lotsfree_percent >= 0) &&
+ (zfs_arc_lotsfree_percent <= 100))
+ arc_lotsfree_percent = zfs_arc_lotsfree_percent;
+
+ /* Valid range: 0 - <all physical memory> */
+ if ((zfs_arc_sys_free) && (zfs_arc_sys_free != arc_sys_free))
+ arc_sys_free = MIN(MAX(zfs_arc_sys_free, 0), allmem);
+
+}
+
+static void
+arc_state_init(void)
+{
+ arc_anon = &ARC_anon;
+ arc_mru = &ARC_mru;
+ arc_mru_ghost = &ARC_mru_ghost;
+ arc_mfu = &ARC_mfu;
+ arc_mfu_ghost = &ARC_mfu_ghost;
+ arc_l2c_only = &ARC_l2c_only;
+
+ arc_mru->arcs_list[ARC_BUFC_METADATA] =
+ multilist_create(sizeof (arc_buf_hdr_t),
+ offsetof(arc_buf_hdr_t, b_l1hdr.b_arc_node),
+ arc_state_multilist_index_func);
+ arc_mru->arcs_list[ARC_BUFC_DATA] =
+ multilist_create(sizeof (arc_buf_hdr_t),
+ offsetof(arc_buf_hdr_t, b_l1hdr.b_arc_node),
+ arc_state_multilist_index_func);
+ arc_mru_ghost->arcs_list[ARC_BUFC_METADATA] =
+ multilist_create(sizeof (arc_buf_hdr_t),
+ offsetof(arc_buf_hdr_t, b_l1hdr.b_arc_node),
+ arc_state_multilist_index_func);
+ arc_mru_ghost->arcs_list[ARC_BUFC_DATA] =
+ multilist_create(sizeof (arc_buf_hdr_t),
+ offsetof(arc_buf_hdr_t, b_l1hdr.b_arc_node),
+ arc_state_multilist_index_func);
+ arc_mfu->arcs_list[ARC_BUFC_METADATA] =
+ multilist_create(sizeof (arc_buf_hdr_t),
+ offsetof(arc_buf_hdr_t, b_l1hdr.b_arc_node),
+ arc_state_multilist_index_func);
+ arc_mfu->arcs_list[ARC_BUFC_DATA] =
+ multilist_create(sizeof (arc_buf_hdr_t),
+ offsetof(arc_buf_hdr_t, b_l1hdr.b_arc_node),
+ arc_state_multilist_index_func);
+ arc_mfu_ghost->arcs_list[ARC_BUFC_METADATA] =
+ multilist_create(sizeof (arc_buf_hdr_t),
+ offsetof(arc_buf_hdr_t, b_l1hdr.b_arc_node),
+ arc_state_multilist_index_func);
+ arc_mfu_ghost->arcs_list[ARC_BUFC_DATA] =
+ multilist_create(sizeof (arc_buf_hdr_t),
+ offsetof(arc_buf_hdr_t, b_l1hdr.b_arc_node),
+ arc_state_multilist_index_func);
+ arc_l2c_only->arcs_list[ARC_BUFC_METADATA] =
+ multilist_create(sizeof (arc_buf_hdr_t),
+ offsetof(arc_buf_hdr_t, b_l1hdr.b_arc_node),
+ arc_state_multilist_index_func);
+ arc_l2c_only->arcs_list[ARC_BUFC_DATA] =
+ multilist_create(sizeof (arc_buf_hdr_t),
+ offsetof(arc_buf_hdr_t, b_l1hdr.b_arc_node),
+ arc_state_multilist_index_func);
+
+ refcount_create(&arc_anon->arcs_esize[ARC_BUFC_METADATA]);
+ refcount_create(&arc_anon->arcs_esize[ARC_BUFC_DATA]);
+ refcount_create(&arc_mru->arcs_esize[ARC_BUFC_METADATA]);
+ refcount_create(&arc_mru->arcs_esize[ARC_BUFC_DATA]);
+ refcount_create(&arc_mru_ghost->arcs_esize[ARC_BUFC_METADATA]);
+ refcount_create(&arc_mru_ghost->arcs_esize[ARC_BUFC_DATA]);
+ refcount_create(&arc_mfu->arcs_esize[ARC_BUFC_METADATA]);
+ refcount_create(&arc_mfu->arcs_esize[ARC_BUFC_DATA]);
+ refcount_create(&arc_mfu_ghost->arcs_esize[ARC_BUFC_METADATA]);
+ refcount_create(&arc_mfu_ghost->arcs_esize[ARC_BUFC_DATA]);
+ refcount_create(&arc_l2c_only->arcs_esize[ARC_BUFC_METADATA]);
+ refcount_create(&arc_l2c_only->arcs_esize[ARC_BUFC_DATA]);
+
+ refcount_create(&arc_anon->arcs_size);
+ refcount_create(&arc_mru->arcs_size);
+ refcount_create(&arc_mru_ghost->arcs_size);
+ refcount_create(&arc_mfu->arcs_size);
+ refcount_create(&arc_mfu_ghost->arcs_size);
+ refcount_create(&arc_l2c_only->arcs_size);
+
+ arc_anon->arcs_state = ARC_STATE_ANON;
+ arc_mru->arcs_state = ARC_STATE_MRU;
+ arc_mru_ghost->arcs_state = ARC_STATE_MRU_GHOST;
+ arc_mfu->arcs_state = ARC_STATE_MFU;
+ arc_mfu_ghost->arcs_state = ARC_STATE_MFU_GHOST;
+ arc_l2c_only->arcs_state = ARC_STATE_L2C_ONLY;
+}
+
+static void
+arc_state_fini(void)
+{
+ refcount_destroy(&arc_anon->arcs_esize[ARC_BUFC_METADATA]);
+ refcount_destroy(&arc_anon->arcs_esize[ARC_BUFC_DATA]);
+ refcount_destroy(&arc_mru->arcs_esize[ARC_BUFC_METADATA]);
+ refcount_destroy(&arc_mru->arcs_esize[ARC_BUFC_DATA]);
+ refcount_destroy(&arc_mru_ghost->arcs_esize[ARC_BUFC_METADATA]);
+ refcount_destroy(&arc_mru_ghost->arcs_esize[ARC_BUFC_DATA]);
+ refcount_destroy(&arc_mfu->arcs_esize[ARC_BUFC_METADATA]);
+ refcount_destroy(&arc_mfu->arcs_esize[ARC_BUFC_DATA]);
+ refcount_destroy(&arc_mfu_ghost->arcs_esize[ARC_BUFC_METADATA]);
+ refcount_destroy(&arc_mfu_ghost->arcs_esize[ARC_BUFC_DATA]);
+ refcount_destroy(&arc_l2c_only->arcs_esize[ARC_BUFC_METADATA]);
+ refcount_destroy(&arc_l2c_only->arcs_esize[ARC_BUFC_DATA]);
+
+ refcount_destroy(&arc_anon->arcs_size);
+ refcount_destroy(&arc_mru->arcs_size);
+ refcount_destroy(&arc_mru_ghost->arcs_size);
+ refcount_destroy(&arc_mfu->arcs_size);
+ refcount_destroy(&arc_mfu_ghost->arcs_size);
+ refcount_destroy(&arc_l2c_only->arcs_size);
+
+ multilist_destroy(arc_mru->arcs_list[ARC_BUFC_METADATA]);
+ multilist_destroy(arc_mru_ghost->arcs_list[ARC_BUFC_METADATA]);
+ multilist_destroy(arc_mfu->arcs_list[ARC_BUFC_METADATA]);
+ multilist_destroy(arc_mfu_ghost->arcs_list[ARC_BUFC_METADATA]);
+ multilist_destroy(arc_mru->arcs_list[ARC_BUFC_DATA]);
+ multilist_destroy(arc_mru_ghost->arcs_list[ARC_BUFC_DATA]);
+ multilist_destroy(arc_mfu->arcs_list[ARC_BUFC_DATA]);
+ multilist_destroy(arc_mfu_ghost->arcs_list[ARC_BUFC_DATA]);
+ multilist_destroy(arc_l2c_only->arcs_list[ARC_BUFC_METADATA]);
+ multilist_destroy(arc_l2c_only->arcs_list[ARC_BUFC_DATA]);
+}
+
+uint64_t
+arc_target_bytes(void)
+{
+ return (arc_c);
+}
+
void
arc_init(void)
{
+ uint64_t percent, allmem = arc_all_memory();
+
mutex_init(&arc_reclaim_lock, NULL, MUTEX_DEFAULT, NULL);
cv_init(&arc_reclaim_thread_cv, NULL, CV_DEFAULT, NULL);
cv_init(&arc_reclaim_waiters_cv, NULL, CV_DEFAULT, NULL);
- mutex_init(&arc_user_evicts_lock, NULL, MUTEX_DEFAULT, NULL);
- cv_init(&arc_user_evicts_cv, NULL, CV_DEFAULT, NULL);
-
/* Convert seconds to clock ticks */
- zfs_arc_min_prefetch_lifespan = 1 * hz;
-
- /* Start out with 1/8 of all memory */
- arc_c = physmem * PAGESIZE / 8;
+ arc_min_prefetch_lifespan = 1 * hz;
#ifdef _KERNEL
- /*
- * On architectures where the physical memory can be larger
- * than the addressable space (intel in 32-bit mode), we may
- * need to limit the cache to 1/8 of VM size.
- */
- arc_c = MIN(arc_c, vmem_size(heap_arena, VMEM_ALLOC | VMEM_FREE) / 8);
/*
* Register a shrinker to support synchronous (direct) memory
* reclaim from the arc. This is done to prevent kswapd from
* swapping out pages when it is preferable to shrink the arc.
*/
spl_register_shrinker(&arc_shrinker);
+
+ /* Set to 1/64 of all memory or a minimum of 512K */
+ arc_sys_free = MAX(allmem / 64, (512 * 1024));
+ arc_need_free = 0;
#endif
- /* set min cache to allow safe operation of arc_adapt() */
- arc_c_min = 2ULL << SPA_MAXBLOCKSHIFT;
- /* set max to 1/2 of all memory */
- arc_c_max = arc_c * 4;
+ /* Set max to 1/2 of all memory */
+ arc_c_max = allmem / 2;
+#ifdef _KERNEL
+ /* Set min cache to 1/32 of all memory, or 32MB, whichever is more */
+ arc_c_min = MAX(allmem / 32, 2ULL << SPA_MAXBLOCKSHIFT);
+#else
/*
- * Allow the tunables to override our calculations if they are
- * reasonable (ie. over 64MB)
+ * In userland, there's only the memory pressure that we artificially
+ * create (see arc_available_memory()). Don't let arc_c get too
+ * small, because it can cause transactions to be larger than
+ * arc_c, causing arc_tempreserve_space() to fail.
*/
- if (zfs_arc_max > 64<<20 && zfs_arc_max < physmem * PAGESIZE)
- arc_c_max = zfs_arc_max;
- if (zfs_arc_min >= 2ULL << SPA_MAXBLOCKSHIFT &&
- zfs_arc_min <= arc_c_max)
- arc_c_min = zfs_arc_min;
+ arc_c_min = MAX(arc_c_max / 2, 2ULL << SPA_MAXBLOCKSHIFT);
+#endif
arc_c = arc_c_max;
arc_p = (arc_c >> 1);
-
- /* limit meta-data to 3/4 of the arc capacity */
- arc_meta_limit = (3 * arc_c_max) / 4;
- arc_meta_max = 0;
-
- /* Allow the tunable to override if it is reasonable */
- if (zfs_arc_meta_limit > 0 && zfs_arc_meta_limit <= arc_c_max)
- arc_meta_limit = zfs_arc_meta_limit;
-
- if (zfs_arc_num_sublists_per_state < 1)
- zfs_arc_num_sublists_per_state = num_online_cpus();
-
- /* if kmem_flags are set, lets try to use less memory */
- if (kmem_debugging())
- arc_c = arc_c / 2;
- if (arc_c < arc_c_min)
- arc_c = arc_c_min;
-
- arc_anon = &ARC_anon;
- arc_mru = &ARC_mru;
- arc_mru_ghost = &ARC_mru_ghost;
- arc_mfu = &ARC_mfu;
- arc_mfu_ghost = &ARC_mfu_ghost;
- arc_l2c_only = &ARC_l2c_only;
arc_size = 0;
- multilist_create(&arc_mru->arcs_list[ARC_BUFC_METADATA],
- sizeof (arc_buf_hdr_t),
- offsetof(arc_buf_hdr_t, b_l1hdr.b_arc_node),
- zfs_arc_num_sublists_per_state, arc_state_multilist_index_func);
- multilist_create(&arc_mru->arcs_list[ARC_BUFC_DATA],
- sizeof (arc_buf_hdr_t),
- offsetof(arc_buf_hdr_t, b_l1hdr.b_arc_node),
- zfs_arc_num_sublists_per_state, arc_state_multilist_index_func);
- multilist_create(&arc_mru_ghost->arcs_list[ARC_BUFC_METADATA],
- sizeof (arc_buf_hdr_t),
- offsetof(arc_buf_hdr_t, b_l1hdr.b_arc_node),
- zfs_arc_num_sublists_per_state, arc_state_multilist_index_func);
- multilist_create(&arc_mru_ghost->arcs_list[ARC_BUFC_DATA],
- sizeof (arc_buf_hdr_t),
- offsetof(arc_buf_hdr_t, b_l1hdr.b_arc_node),
- zfs_arc_num_sublists_per_state, arc_state_multilist_index_func);
- multilist_create(&arc_mfu->arcs_list[ARC_BUFC_METADATA],
- sizeof (arc_buf_hdr_t),
- offsetof(arc_buf_hdr_t, b_l1hdr.b_arc_node),
- zfs_arc_num_sublists_per_state, arc_state_multilist_index_func);
- multilist_create(&arc_mfu->arcs_list[ARC_BUFC_DATA],
- sizeof (arc_buf_hdr_t),
- offsetof(arc_buf_hdr_t, b_l1hdr.b_arc_node),
- zfs_arc_num_sublists_per_state, arc_state_multilist_index_func);
- multilist_create(&arc_mfu_ghost->arcs_list[ARC_BUFC_METADATA],
- sizeof (arc_buf_hdr_t),
- offsetof(arc_buf_hdr_t, b_l1hdr.b_arc_node),
- zfs_arc_num_sublists_per_state, arc_state_multilist_index_func);
- multilist_create(&arc_mfu_ghost->arcs_list[ARC_BUFC_DATA],
- sizeof (arc_buf_hdr_t),
- offsetof(arc_buf_hdr_t, b_l1hdr.b_arc_node),
- zfs_arc_num_sublists_per_state, arc_state_multilist_index_func);
- multilist_create(&arc_l2c_only->arcs_list[ARC_BUFC_METADATA],
- sizeof (arc_buf_hdr_t),
- offsetof(arc_buf_hdr_t, b_l1hdr.b_arc_node),
- zfs_arc_num_sublists_per_state, arc_state_multilist_index_func);
- multilist_create(&arc_l2c_only->arcs_list[ARC_BUFC_DATA],
- sizeof (arc_buf_hdr_t),
- offsetof(arc_buf_hdr_t, b_l1hdr.b_arc_node),
- zfs_arc_num_sublists_per_state, arc_state_multilist_index_func);
+ /* Set min to 1/2 of arc_c_min */
+ arc_meta_min = 1ULL << SPA_MAXBLOCKSHIFT;
+ /* Initialize maximum observed usage to zero */
+ arc_meta_max = 0;
+ /*
+ * Set arc_meta_limit to a percent of arc_c_max with a floor of
+ * arc_meta_min, and a ceiling of arc_c_max.
+ */
+ percent = MIN(zfs_arc_meta_limit_percent, 100);
+ arc_meta_limit = MAX(arc_meta_min, (percent * arc_c_max) / 100);
+ percent = MIN(zfs_arc_dnode_limit_percent, 100);
+ arc_dnode_limit = (percent * arc_meta_limit) / 100;
- arc_anon->arcs_state = ARC_STATE_ANON;
- arc_mru->arcs_state = ARC_STATE_MRU;
- arc_mru_ghost->arcs_state = ARC_STATE_MRU_GHOST;
- arc_mfu->arcs_state = ARC_STATE_MFU;
- arc_mfu_ghost->arcs_state = ARC_STATE_MFU_GHOST;
- arc_l2c_only->arcs_state = ARC_STATE_L2C_ONLY;
+ /* Apply user specified tunings */
+ arc_tuning_update();
+
+ /* if kmem_flags are set, lets try to use less memory */
+ if (kmem_debugging())
+ arc_c = arc_c / 2;
+ if (arc_c < arc_c_min)
+ arc_c = arc_c_min;
+ arc_state_init();
buf_init();
- arc_reclaim_thread_exit = FALSE;
- arc_user_evicts_thread_exit = FALSE;
list_create(&arc_prune_list, sizeof (arc_prune_t),
offsetof(arc_prune_t, p_node));
- arc_eviction_list = NULL;
mutex_init(&arc_prune_mtx, NULL, MUTEX_DEFAULT, NULL);
- bzero(&arc_eviction_hdr, sizeof (arc_buf_hdr_t));
- arc_prune_taskq = taskq_create("arc_prune", max_ncpus, minclsyspri,
- max_ncpus, INT_MAX, TASKQ_PREPOPULATE);
+ arc_prune_taskq = taskq_create("arc_prune", max_ncpus, defclsyspri,
+ max_ncpus, INT_MAX, TASKQ_PREPOPULATE | TASKQ_DYNAMIC);
+
+ arc_reclaim_thread_exit = B_FALSE;
arc_ksp = kstat_create("zfs", 0, "arcstats", "misc", KSTAT_TYPE_NAMED,
sizeof (arc_stats) / sizeof (kstat_named_t), KSTAT_FLAG_VIRTUAL);
kstat_install(arc_ksp);
}
- (void) thread_create(NULL, 0, arc_adapt_thread, NULL, 0, &p0,
- TS_RUN, minclsyspri);
+ (void) thread_create(NULL, 0, arc_reclaim_thread, NULL, 0, &p0,
+ TS_RUN, defclsyspri);
- (void) thread_create(NULL, 0, arc_user_evicts_thread, NULL, 0, &p0,
- TS_RUN, minclsyspri);
-
- arc_dead = FALSE;
+ arc_dead = B_FALSE;
arc_warm = B_FALSE;
/*
* If it has been set by a module parameter, take that.
* Otherwise, use a percentage of physical memory defined by
* zfs_dirty_data_max_percent (default 10%) with a cap at
- * zfs_dirty_data_max_max (default 25% of physical memory).
+ * zfs_dirty_data_max_max (default 4G or 25% of physical memory).
*/
if (zfs_dirty_data_max_max == 0)
- zfs_dirty_data_max_max = physmem * PAGESIZE *
- zfs_dirty_data_max_max_percent / 100;
+ zfs_dirty_data_max_max = MIN(4ULL * 1024 * 1024 * 1024,
+ allmem * zfs_dirty_data_max_max_percent / 100);
if (zfs_dirty_data_max == 0) {
- zfs_dirty_data_max = physmem * PAGESIZE *
+ zfs_dirty_data_max = allmem *
zfs_dirty_data_max_percent / 100;
zfs_dirty_data_max = MIN(zfs_dirty_data_max,
zfs_dirty_data_max_max);
#endif /* _KERNEL */
mutex_enter(&arc_reclaim_lock);
- arc_reclaim_thread_exit = TRUE;
+ arc_reclaim_thread_exit = B_TRUE;
/*
* The reclaim thread will set arc_reclaim_thread_exit back to
- * FALSE when it is finished exiting; we're waiting for that.
+ * B_FALSE when it is finished exiting; we're waiting for that.
*/
while (arc_reclaim_thread_exit) {
cv_signal(&arc_reclaim_thread_cv);
}
mutex_exit(&arc_reclaim_lock);
- mutex_enter(&arc_user_evicts_lock);
- arc_user_evicts_thread_exit = TRUE;
- /*
- * The user evicts thread will set arc_user_evicts_thread_exit
- * to FALSE when it is finished exiting; we're waiting for that.
- */
- while (arc_user_evicts_thread_exit) {
- cv_signal(&arc_user_evicts_cv);
- cv_wait(&arc_user_evicts_cv, &arc_user_evicts_lock);
- }
- mutex_exit(&arc_user_evicts_lock);
-
- /* Use TRUE to ensure *all* buffers are evicted */
- arc_flush(NULL, TRUE);
+ /* Use B_TRUE to ensure *all* buffers are evicted */
+ arc_flush(NULL, B_TRUE);
- arc_dead = TRUE;
+ arc_dead = B_TRUE;
if (arc_ksp != NULL) {
kstat_delete(arc_ksp);
cv_destroy(&arc_reclaim_thread_cv);
cv_destroy(&arc_reclaim_waiters_cv);
- mutex_destroy(&arc_user_evicts_lock);
- cv_destroy(&arc_user_evicts_cv);
-
- multilist_destroy(&arc_mru->arcs_list[ARC_BUFC_METADATA]);
- multilist_destroy(&arc_mru_ghost->arcs_list[ARC_BUFC_METADATA]);
- multilist_destroy(&arc_mfu->arcs_list[ARC_BUFC_METADATA]);
- multilist_destroy(&arc_mfu_ghost->arcs_list[ARC_BUFC_METADATA]);
- multilist_destroy(&arc_mru->arcs_list[ARC_BUFC_DATA]);
- multilist_destroy(&arc_mru_ghost->arcs_list[ARC_BUFC_DATA]);
- multilist_destroy(&arc_mfu->arcs_list[ARC_BUFC_DATA]);
- multilist_destroy(&arc_mfu_ghost->arcs_list[ARC_BUFC_DATA]);
- multilist_destroy(&arc_l2c_only->arcs_list[ARC_BUFC_METADATA]);
- multilist_destroy(&arc_l2c_only->arcs_list[ARC_BUFC_DATA]);
-
+ arc_state_fini();
buf_fini();
ASSERT0(arc_loaned_bytes);
* l2arc_write_max max write bytes per interval
* l2arc_write_boost extra write bytes during device warmup
* l2arc_noprefetch skip caching prefetched buffers
- * l2arc_nocompress skip compressing buffers
* l2arc_headroom number of max device writes to precache
* l2arc_headroom_boost when we find compressed buffers during ARC
* scanning, we multiply headroom by this
for (df = list_tail(buflist); df; df = df_prev) {
df_prev = list_prev(buflist, df);
- ASSERT(df->l2df_data != NULL);
- ASSERT(df->l2df_func != NULL);
- df->l2df_func(df->l2df_data, df->l2df_size);
+ ASSERT3P(df->l2df_abd, !=, NULL);
+ abd_free(df->l2df_abd);
list_remove(buflist, df);
kmem_free(df, sizeof (l2arc_data_free_t));
}
int64_t bytes_dropped = 0;
cb = zio->io_private;
- ASSERT(cb != NULL);
+ ASSERT3P(cb, !=, NULL);
dev = cb->l2wcb_dev;
- ASSERT(dev != NULL);
+ ASSERT3P(dev, !=, NULL);
head = cb->l2wcb_head;
- ASSERT(head != NULL);
+ ASSERT3P(head, !=, NULL);
buflist = &dev->l2ad_buflist;
- ASSERT(buflist != NULL);
+ ASSERT3P(buflist, !=, NULL);
DTRACE_PROBE2(l2arc__iodone, zio_t *, zio,
l2arc_write_callback_t *, cb);
ASSERT(HDR_HAS_L1HDR(hdr));
/*
- * We may have allocated a buffer for L2ARC compression,
- * we must release it to avoid leaking this data.
+ * Skipped - drop L2ARC entry and mark the header as no
+ * longer L2 eligibile.
*/
- l2arc_release_cdata_buf(hdr);
-
if (zio->io_error != 0) {
/*
* Error - drop L2ARC entry.
*/
list_remove(buflist, hdr);
- hdr->b_flags &= ~ARC_FLAG_HAS_L2HDR;
+ arc_hdr_clear_flags(hdr, ARC_FLAG_HAS_L2HDR);
- ARCSTAT_INCR(arcstat_l2_asize, -hdr->b_l2hdr.b_asize);
- ARCSTAT_INCR(arcstat_l2_size, -hdr->b_size);
+ ARCSTAT_INCR(arcstat_l2_psize, -arc_hdr_size(hdr));
+ ARCSTAT_INCR(arcstat_l2_lsize, -HDR_GET_LSIZE(hdr));
+
+ bytes_dropped += arc_hdr_size(hdr);
+ (void) refcount_remove_many(&dev->l2ad_alloc,
+ arc_hdr_size(hdr), hdr);
}
/*
* Allow ARC to begin reads and ghost list evictions to
* this L2ARC entry.
*/
- hdr->b_flags &= ~ARC_FLAG_L2_WRITING;
+ arc_hdr_clear_flags(hdr, ARC_FLAG_L2_WRITING);
mutex_exit(hash_lock);
}
kmem_free(cb, sizeof (l2arc_write_callback_t));
}
+static int
+l2arc_untransform(zio_t *zio, l2arc_read_callback_t *cb)
+{
+ int ret;
+ spa_t *spa = zio->io_spa;
+ arc_buf_hdr_t *hdr = cb->l2rcb_hdr;
+ blkptr_t *bp = zio->io_bp;
+ dsl_crypto_key_t *dck = NULL;
+ uint8_t salt[ZIO_DATA_SALT_LEN];
+ uint8_t iv[ZIO_DATA_IV_LEN];
+ uint8_t mac[ZIO_DATA_MAC_LEN];
+ boolean_t no_crypt = B_FALSE;
+
+ /*
+ * ZIL data is never be written to the L2ARC, so we don't need
+ * special handling for its unique MAC storage.
+ */
+ ASSERT3U(BP_GET_TYPE(bp), !=, DMU_OT_INTENT_LOG);
+ ASSERT(MUTEX_HELD(HDR_LOCK(hdr)));
+
+ /* If the data was encrypted, decrypt it now */
+ if (HDR_ENCRYPTED(hdr)) {
+ abd_t *eabd = arc_get_data_abd(hdr,
+ arc_hdr_size(hdr), hdr);
+
+ zio_crypt_decode_params_bp(bp, salt, iv);
+ zio_crypt_decode_mac_bp(bp, mac);
+
+ ret = spa_keystore_lookup_key(spa,
+ cb->l2rcb_zb.zb_objset, FTAG, &dck);
+ if (ret != 0) {
+ arc_free_data_abd(hdr, eabd, arc_hdr_size(hdr), hdr);
+ goto error;
+ }
+
+ ret = zio_do_crypt_abd(B_FALSE, &dck->dck_key,
+ salt, BP_GET_TYPE(bp), iv, mac, HDR_GET_PSIZE(hdr),
+ BP_SHOULD_BYTESWAP(bp), eabd, hdr->b_l1hdr.b_pabd,
+ &no_crypt);
+ if (ret != 0) {
+ arc_free_data_abd(hdr, eabd, arc_hdr_size(hdr), hdr);
+ spa_keystore_dsl_key_rele(spa, dck, FTAG);
+ goto error;
+ }
+
+ spa_keystore_dsl_key_rele(spa, dck, FTAG);
+
+ /*
+ * If we actually performed decryption, replace b_pabd
+ * with the decrypted data. Otherwise we can just throw
+ * our decryption buffer away.
+ */
+ if (!no_crypt) {
+ arc_free_data_abd(hdr, hdr->b_l1hdr.b_pabd,
+ arc_hdr_size(hdr), hdr);
+ hdr->b_l1hdr.b_pabd = eabd;
+ zio->io_abd = eabd;
+ } else {
+ arc_free_data_abd(hdr, eabd, arc_hdr_size(hdr), hdr);
+ }
+ }
+
+ /*
+ * If the L2ARC block was compressed, but ARC compression
+ * is disabled we decompress the data into a new buffer and
+ * replace the existing data.
+ */
+ if (HDR_GET_COMPRESS(hdr) != ZIO_COMPRESS_OFF &&
+ !HDR_COMPRESSION_ENABLED(hdr)) {
+ abd_t *cabd = arc_get_data_abd(hdr, arc_hdr_size(hdr), hdr);
+ void *tmp = abd_borrow_buf(cabd, arc_hdr_size(hdr));
+
+ ret = zio_decompress_data(HDR_GET_COMPRESS(hdr),
+ hdr->b_l1hdr.b_pabd, tmp, HDR_GET_PSIZE(hdr),
+ HDR_GET_LSIZE(hdr));
+ if (ret != 0) {
+ abd_return_buf_copy(cabd, tmp, arc_hdr_size(hdr));
+ arc_free_data_abd(hdr, cabd, arc_hdr_size(hdr), hdr);
+ goto error;
+ }
+
+ abd_return_buf_copy(cabd, tmp, arc_hdr_size(hdr));
+ arc_free_data_abd(hdr, hdr->b_l1hdr.b_pabd,
+ arc_hdr_size(hdr), hdr);
+ hdr->b_l1hdr.b_pabd = cabd;
+ zio->io_abd = cabd;
+ zio->io_size = HDR_GET_LSIZE(hdr);
+ }
+
+ return (0);
+
+error:
+ return (ret);
+}
+
+
/*
* A read to a cache device completed. Validate buffer contents before
* handing over to the regular ARC routines.
static void
l2arc_read_done(zio_t *zio)
{
+ int tfm_error = 0;
l2arc_read_callback_t *cb;
arc_buf_hdr_t *hdr;
- arc_buf_t *buf;
kmutex_t *hash_lock;
- int equal;
+ boolean_t valid_cksum, using_rdata;
- ASSERT(zio->io_vd != NULL);
+ ASSERT3P(zio->io_vd, !=, NULL);
ASSERT(zio->io_flags & ZIO_FLAG_DONT_PROPAGATE);
spa_config_exit(zio->io_spa, SCL_L2ARC, zio->io_vd);
cb = zio->io_private;
- ASSERT(cb != NULL);
- buf = cb->l2rcb_buf;
- ASSERT(buf != NULL);
+ ASSERT3P(cb, !=, NULL);
+ hdr = cb->l2rcb_hdr;
+ ASSERT3P(hdr, !=, NULL);
- hash_lock = HDR_LOCK(buf->b_hdr);
+ hash_lock = HDR_LOCK(hdr);
mutex_enter(hash_lock);
- hdr = buf->b_hdr;
ASSERT3P(hash_lock, ==, HDR_LOCK(hdr));
/*
- * If the buffer was compressed, decompress it first.
+ * If the data was read into a temporary buffer,
+ * move it and free the buffer.
*/
- if (cb->l2rcb_compress != ZIO_COMPRESS_OFF)
- l2arc_decompress_zio(zio, hdr, cb->l2rcb_compress);
- ASSERT(zio->io_data != NULL);
+ if (cb->l2rcb_abd != NULL) {
+ ASSERT3U(arc_hdr_size(hdr), <, zio->io_size);
+ if (zio->io_error == 0) {
+ abd_copy(hdr->b_l1hdr.b_pabd, cb->l2rcb_abd,
+ arc_hdr_size(hdr));
+ }
+
+ /*
+ * The following must be done regardless of whether
+ * there was an error:
+ * - free the temporary buffer
+ * - point zio to the real ARC buffer
+ * - set zio size accordingly
+ * These are required because zio is either re-used for
+ * an I/O of the block in the case of the error
+ * or the zio is passed to arc_read_done() and it
+ * needs real data.
+ */
+ abd_free(cb->l2rcb_abd);
+ zio->io_size = zio->io_orig_size = arc_hdr_size(hdr);
+ zio->io_abd = zio->io_orig_abd = hdr->b_l1hdr.b_pabd;
+ }
+
+ ASSERT3P(zio->io_abd, !=, NULL);
/*
* Check this survived the L2ARC journey.
*/
- equal = arc_cksum_equal(buf);
- if (equal && zio->io_error == 0 && !HDR_L2_EVICTED(hdr)) {
+ ASSERT(zio->io_abd == hdr->b_l1hdr.b_pabd ||
+ (HDR_HAS_RABD(hdr) && zio->io_abd == hdr->b_crypt_hdr.b_rabd));
+ zio->io_bp_copy = cb->l2rcb_bp; /* XXX fix in L2ARC 2.0 */
+ zio->io_bp = &zio->io_bp_copy; /* XXX fix in L2ARC 2.0 */
+
+ valid_cksum = arc_cksum_is_equal(hdr, zio);
+ using_rdata = (HDR_HAS_RABD(hdr) &&
+ zio->io_abd == hdr->b_crypt_hdr.b_rabd);
+
+ /*
+ * b_rabd will always match the data as it exists on disk if it is
+ * being used. Therefore if we are reading into b_rabd we do not
+ * attempt to untransform the data.
+ */
+ if (valid_cksum && !using_rdata)
+ tfm_error = l2arc_untransform(zio, cb);
+
+ if (valid_cksum && tfm_error == 0 && zio->io_error == 0 &&
+ !HDR_L2_EVICTED(hdr)) {
mutex_exit(hash_lock);
- zio->io_private = buf;
- zio->io_bp_copy = cb->l2rcb_bp; /* XXX fix in L2ARC 2.0 */
- zio->io_bp = &zio->io_bp_copy; /* XXX fix in L2ARC 2.0 */
+ zio->io_private = hdr;
arc_read_done(zio);
} else {
mutex_exit(hash_lock);
} else {
zio->io_error = SET_ERROR(EIO);
}
- if (!equal)
+ if (!valid_cksum || tfm_error != 0)
ARCSTAT_BUMP(arcstat_l2_cksum_bad);
/*
*/
if (zio->io_waiter == NULL) {
zio_t *pio = zio_unique_parent(zio);
+ void *abd = (using_rdata) ?
+ hdr->b_crypt_hdr.b_rabd : hdr->b_l1hdr.b_pabd;
ASSERT(!pio || pio->io_child_type == ZIO_CHILD_LOGICAL);
- zio_nowait(zio_read(pio, cb->l2rcb_spa, &cb->l2rcb_bp,
- buf->b_data, zio->io_size, arc_read_done, buf,
- zio->io_priority, cb->l2rcb_flags, &cb->l2rcb_zb));
+ zio_nowait(zio_read(pio, zio->io_spa, zio->io_bp,
+ abd, zio->io_size, arc_read_done,
+ hdr, zio->io_priority, cb->l2rcb_flags,
+ &cb->l2rcb_zb));
}
}
multilist_t *ml = NULL;
unsigned int idx;
- ASSERT(list_num >= 0 && list_num <= 3);
+ ASSERT(list_num >= 0 && list_num < L2ARC_FEED_TYPES);
switch (list_num) {
case 0:
- ml = &arc_mfu->arcs_list[ARC_BUFC_METADATA];
+ ml = arc_mfu->arcs_list[ARC_BUFC_METADATA];
break;
case 1:
- ml = &arc_mru->arcs_list[ARC_BUFC_METADATA];
+ ml = arc_mru->arcs_list[ARC_BUFC_METADATA];
break;
case 2:
- ml = &arc_mfu->arcs_list[ARC_BUFC_DATA];
+ ml = arc_mfu->arcs_list[ARC_BUFC_DATA];
break;
case 3:
- ml = &arc_mru->arcs_list[ARC_BUFC_DATA];
+ ml = arc_mru->arcs_list[ARC_BUFC_DATA];
break;
+ default:
+ return (NULL);
}
/*
arc_buf_hdr_t *hdr, *hdr_prev;
kmutex_t *hash_lock;
uint64_t taddr;
- int64_t bytes_evicted = 0;
buflist = &dev->l2ad_buflist;
goto top;
}
- if (HDR_L2_WRITE_HEAD(hdr)) {
- /*
- * We hit a write head node. Leave it for
- * l2arc_write_done().
- */
- list_remove(buflist, hdr);
- mutex_exit(hash_lock);
- continue;
- }
+ /*
+ * A header can't be on this list if it doesn't have L2 header.
+ */
+ ASSERT(HDR_HAS_L2HDR(hdr));
- if (!all && HDR_HAS_L2HDR(hdr) &&
- (hdr->b_l2hdr.b_daddr > taddr ||
+ /* Ensure this header has finished being written. */
+ ASSERT(!HDR_L2_WRITING(hdr));
+ ASSERT(!HDR_L2_WRITE_HEAD(hdr));
+
+ if (!all && (hdr->b_l2hdr.b_daddr >= taddr ||
hdr->b_l2hdr.b_daddr < dev->l2ad_hand)) {
/*
* We've evicted to the target address,
break;
}
- ASSERT(HDR_HAS_L2HDR(hdr));
if (!HDR_HAS_L1HDR(hdr)) {
ASSERT(!HDR_L2_READING(hdr));
/*
* This doesn't exist in the ARC. Destroy.
* arc_hdr_destroy() will call list_remove()
- * and decrement arcstat_l2_size.
+ * and decrement arcstat_l2_lsize.
*/
arc_change_state(arc_anon, hdr, hash_lock);
arc_hdr_destroy(hdr);
*/
if (HDR_L2_READING(hdr)) {
ARCSTAT_BUMP(arcstat_l2_evict_reading);
- hdr->b_flags |= ARC_FLAG_L2_EVICTED;
+ arc_hdr_set_flags(hdr, ARC_FLAG_L2_EVICTED);
}
- /*
- * Tell ARC this no longer exists in L2ARC.
- */
- /* Tell ARC this no longer exists in L2ARC. */
- ARCSTAT_INCR(arcstat_l2_asize, -hdr->b_l2hdr.b_asize);
- ARCSTAT_INCR(arcstat_l2_size, -hdr->b_size);
- hdr->b_flags &= ~ARC_FLAG_HAS_L2HDR;
- list_remove(buflist, hdr);
-
- /* Ensure this header has finished being written */
- ASSERT(!HDR_L2_WRITING(hdr));
- ASSERT3P(hdr->b_l1hdr.b_tmp_cdata, ==, NULL);
+ arc_hdr_l2hdr_destroy(hdr);
}
mutex_exit(hash_lock);
}
mutex_exit(&dev->l2ad_mtx);
+}
+
+/*
+ * Handle any abd transforms that might be required for writing to the L2ARC.
+ * If successful, this function will always return an abd with the data
+ * transformed as it is on disk in a new abd of asize bytes.
+ */
+static int
+l2arc_apply_transforms(spa_t *spa, arc_buf_hdr_t *hdr, uint64_t asize,
+ abd_t **abd_out)
+{
+ int ret;
+ void *tmp = NULL;
+ abd_t *cabd = NULL, *eabd = NULL, *to_write = hdr->b_l1hdr.b_pabd;
+ enum zio_compress compress = HDR_GET_COMPRESS(hdr);
+ uint64_t psize = HDR_GET_PSIZE(hdr);
+ uint64_t size = arc_hdr_size(hdr);
+ boolean_t ismd = HDR_ISTYPE_METADATA(hdr);
+ boolean_t bswap = (hdr->b_l1hdr.b_byteswap != DMU_BSWAP_NUMFUNCS);
+ dsl_crypto_key_t *dck = NULL;
+ uint8_t mac[ZIO_DATA_MAC_LEN] = { 0 };
+ boolean_t no_crypt = B_FALSE;
+
+ ASSERT((HDR_GET_COMPRESS(hdr) != ZIO_COMPRESS_OFF &&
+ !HDR_COMPRESSION_ENABLED(hdr)) ||
+ HDR_ENCRYPTED(hdr) || HDR_SHARED_DATA(hdr) || psize != asize);
+ ASSERT3U(psize, <=, asize);
+
+ /*
+ * If this data simply needs its own buffer, we simply allocate it
+ * and copy the data. This may be done to elimiate a depedency on a
+ * shared buffer or to reallocate the buffer to match asize.
+ */
+ if (HDR_HAS_RABD(hdr) && asize != psize) {
+ ASSERT3U(size, ==, psize);
+ to_write = abd_alloc_for_io(asize, ismd);
+ abd_copy(to_write, hdr->b_crypt_hdr.b_rabd, size);
+ if (size != asize)
+ abd_zero_off(to_write, size, asize - size);
+ goto out;
+ }
+
+ if ((compress == ZIO_COMPRESS_OFF || HDR_COMPRESSION_ENABLED(hdr)) &&
+ !HDR_ENCRYPTED(hdr)) {
+ ASSERT3U(size, ==, psize);
+ to_write = abd_alloc_for_io(asize, ismd);
+ abd_copy(to_write, hdr->b_l1hdr.b_pabd, size);
+ if (size != asize)
+ abd_zero_off(to_write, size, asize - size);
+ goto out;
+ }
+
+ if (compress != ZIO_COMPRESS_OFF && !HDR_COMPRESSION_ENABLED(hdr)) {
+ cabd = abd_alloc_for_io(asize, ismd);
+ tmp = abd_borrow_buf(cabd, asize);
+
+ psize = zio_compress_data(compress, to_write, tmp, size);
+ ASSERT3U(psize, <=, HDR_GET_PSIZE(hdr));
+ if (psize < asize)
+ bzero((char *)tmp + psize, asize - psize);
+ psize = HDR_GET_PSIZE(hdr);
+ abd_return_buf_copy(cabd, tmp, asize);
+ to_write = cabd;
+ }
+
+ if (HDR_ENCRYPTED(hdr)) {
+ eabd = abd_alloc_for_io(asize, ismd);
+
+ /*
+ * If the dataset was disowned before the buffer
+ * made it to this point, the key to re-encrypt
+ * it won't be available. In this case we simply
+ * won't write the buffer to the L2ARC.
+ */
+ ret = spa_keystore_lookup_key(spa, hdr->b_crypt_hdr.b_dsobj,
+ FTAG, &dck);
+ if (ret != 0)
+ goto error;
+
+ ret = zio_do_crypt_abd(B_TRUE, &dck->dck_key,
+ hdr->b_crypt_hdr.b_salt, hdr->b_crypt_hdr.b_ot,
+ hdr->b_crypt_hdr.b_iv, mac, psize, bswap, to_write,
+ eabd, &no_crypt);
+ if (ret != 0)
+ goto error;
+
+ if (no_crypt)
+ abd_copy(eabd, to_write, psize);
+
+ if (psize != asize)
+ abd_zero_off(eabd, psize, asize - psize);
+
+ /* assert that the MAC we got here matches the one we saved */
+ ASSERT0(bcmp(mac, hdr->b_crypt_hdr.b_mac, ZIO_DATA_MAC_LEN));
+ spa_keystore_dsl_key_rele(spa, dck, FTAG);
+
+ if (to_write == cabd)
+ abd_free(cabd);
+
+ to_write = eabd;
+ }
- vdev_space_update(dev->l2ad_vdev, -bytes_evicted, 0, 0);
- dev->l2ad_evict = taddr;
+out:
+ ASSERT3P(to_write, !=, hdr->b_l1hdr.b_pabd);
+ *abd_out = to_write;
+ return (0);
+
+error:
+ if (dck != NULL)
+ spa_keystore_dsl_key_rele(spa, dck, FTAG);
+ if (cabd != NULL)
+ abd_free(cabd);
+ if (eabd != NULL)
+ abd_free(eabd);
+
+ *abd_out = NULL;
+ return (ret);
}
/*
* the delta by which the device hand has changed due to alignment).
*/
static uint64_t
-l2arc_write_buffers(spa_t *spa, l2arc_dev_t *dev, uint64_t target_sz,
- boolean_t *headroom_boost)
+l2arc_write_buffers(spa_t *spa, l2arc_dev_t *dev, uint64_t target_sz)
{
arc_buf_hdr_t *hdr, *hdr_prev, *head;
- uint64_t write_asize, write_psize, write_sz, headroom,
- buf_compress_minsz;
- void *buf_data;
+ uint64_t write_asize, write_psize, write_lsize, headroom;
boolean_t full;
l2arc_write_callback_t *cb;
zio_t *pio, *wzio;
uint64_t guid = spa_load_guid(spa);
int try;
- const boolean_t do_headroom_boost = *headroom_boost;
- ASSERT(dev->l2ad_vdev != NULL);
-
- /* Lower the flag now, we might want to raise it again later. */
- *headroom_boost = B_FALSE;
+ ASSERT3P(dev->l2ad_vdev, !=, NULL);
pio = NULL;
- write_sz = write_asize = write_psize = 0;
+ write_lsize = write_asize = write_psize = 0;
full = B_FALSE;
head = kmem_cache_alloc(hdr_l2only_cache, KM_PUSHPAGE);
- head->b_flags |= ARC_FLAG_L2_WRITE_HEAD;
- head->b_flags |= ARC_FLAG_HAS_L2HDR;
-
- /*
- * We will want to try to compress buffers that are at least 2x the
- * device sector size.
- */
- buf_compress_minsz = 2 << dev->l2ad_vdev->vdev_ashift;
+ arc_hdr_set_flags(head, ARC_FLAG_L2_WRITE_HEAD | ARC_FLAG_HAS_L2HDR);
/*
* Copy buffers for L2ARC writing.
*/
- for (try = 0; try <= 3; try++) {
+ for (try = 0; try < L2ARC_FEED_TYPES; try++) {
multilist_sublist_t *mls = l2arc_sublist_lock(try);
uint64_t passed_sz = 0;
+ VERIFY3P(mls, !=, NULL);
+
/*
* L2ARC fast warmup.
*
hdr = multilist_sublist_tail(mls);
headroom = target_sz * l2arc_headroom;
- if (do_headroom_boost)
+ if (zfs_compressed_arc_enabled)
headroom = (headroom * l2arc_headroom_boost) / 100;
for (; hdr; hdr = hdr_prev) {
kmutex_t *hash_lock;
- uint64_t buf_sz;
+ abd_t *to_write = NULL;
if (arc_warm == B_FALSE)
hdr_prev = multilist_sublist_next(mls, hdr);
continue;
}
- passed_sz += hdr->b_size;
+ passed_sz += HDR_GET_LSIZE(hdr);
if (passed_sz > headroom) {
/*
* Searched too far.
continue;
}
- if ((write_sz + hdr->b_size) > target_sz) {
+ /*
+ * We rely on the L1 portion of the header below, so
+ * it's invalid for this header to have been evicted out
+ * of the ghost cache, prior to being written out. The
+ * ARC_FLAG_L2_WRITING bit ensures this won't happen.
+ */
+ ASSERT(HDR_HAS_L1HDR(hdr));
+
+ ASSERT3U(HDR_GET_PSIZE(hdr), >, 0);
+ ASSERT3U(arc_hdr_size(hdr), >, 0);
+ ASSERT(hdr->b_l1hdr.b_pabd != NULL ||
+ HDR_HAS_RABD(hdr));
+ uint64_t psize = HDR_GET_PSIZE(hdr);
+ uint64_t asize = vdev_psize_to_asize(dev->l2ad_vdev,
+ psize);
+
+ if ((write_asize + asize) > target_sz) {
full = B_TRUE;
mutex_exit(hash_lock);
break;
}
+ /*
+ * We rely on the L1 portion of the header below, so
+ * it's invalid for this header to have been evicted out
+ * of the ghost cache, prior to being written out. The
+ * ARC_FLAG_L2_WRITING bit ensures this won't happen.
+ */
+ arc_hdr_set_flags(hdr, ARC_FLAG_L2_WRITING);
+ ASSERT(HDR_HAS_L1HDR(hdr));
+
+ ASSERT3U(HDR_GET_PSIZE(hdr), >, 0);
+ ASSERT(hdr->b_l1hdr.b_pabd != NULL ||
+ HDR_HAS_RABD(hdr));
+ ASSERT3U(arc_hdr_size(hdr), >, 0);
+
+ /*
+ * If this header has b_rabd, we can use this since it
+ * must always match the data exactly as it exists on
+ * disk. Otherwise, the L2ARC can normally use the
+ * hdr's data, but if we're sharing data between the
+ * hdr and one of its bufs, L2ARC needs its own copy of
+ * the data so that the ZIO below can't race with the
+ * buf consumer. To ensure that this copy will be
+ * available for the lifetime of the ZIO and be cleaned
+ * up afterwards, we add it to the l2arc_free_on_write
+ * queue. If we need to apply any transforms to the
+ * data (compression, encryption) we will also need the
+ * extra buffer.
+ */
+ if (HDR_HAS_RABD(hdr) && psize == asize) {
+ to_write = hdr->b_crypt_hdr.b_rabd;
+ } else if ((HDR_COMPRESSION_ENABLED(hdr) ||
+ HDR_GET_COMPRESS(hdr) == ZIO_COMPRESS_OFF) &&
+ !HDR_ENCRYPTED(hdr) && !HDR_SHARED_DATA(hdr) &&
+ psize == asize) {
+ to_write = hdr->b_l1hdr.b_pabd;
+ } else {
+ int ret;
+ arc_buf_contents_t type = arc_buf_type(hdr);
+
+ ret = l2arc_apply_transforms(spa, hdr, asize,
+ &to_write);
+ if (ret != 0) {
+ arc_hdr_clear_flags(hdr,
+ ARC_FLAG_L2_WRITING);
+ mutex_exit(hash_lock);
+ continue;
+ }
+
+ l2arc_free_abd_on_write(to_write, asize, type);
+ }
+
if (pio == NULL) {
/*
* Insert a dummy header on the buflist so
list_insert_head(&dev->l2ad_buflist, head);
mutex_exit(&dev->l2ad_mtx);
- cb = kmem_alloc(sizeof (l2arc_write_callback_t),
- KM_SLEEP);
+ cb = kmem_alloc(
+ sizeof (l2arc_write_callback_t), KM_SLEEP);
cb->l2wcb_dev = dev;
cb->l2wcb_head = head;
pio = zio_root(spa, l2arc_write_done, cb,
ZIO_FLAG_CANFAIL);
}
- /*
- * Create and add a new L2ARC header.
- */
hdr->b_l2hdr.b_dev = dev;
- arc_space_consume(HDR_L2ONLY_SIZE, ARC_SPACE_L2HDRS);
- hdr->b_flags |= ARC_FLAG_L2_WRITING;
- /*
- * Temporarily stash the data buffer in b_tmp_cdata.
- * The subsequent write step will pick it up from
- * there. This is because can't access b_l1hdr.b_buf
- * without holding the hash_lock, which we in turn
- * can't access without holding the ARC list locks
- * (which we want to avoid during compression/writing)
- */
- HDR_SET_COMPRESS(hdr, ZIO_COMPRESS_OFF);
- hdr->b_l2hdr.b_asize = hdr->b_size;
hdr->b_l2hdr.b_hits = 0;
- hdr->b_l1hdr.b_tmp_cdata = hdr->b_l1hdr.b_buf->b_data;
- buf_sz = hdr->b_size;
- hdr->b_flags |= ARC_FLAG_HAS_L2HDR;
+ hdr->b_l2hdr.b_daddr = dev->l2ad_hand;
+ arc_hdr_set_flags(hdr, ARC_FLAG_HAS_L2HDR);
mutex_enter(&dev->l2ad_mtx);
list_insert_head(&dev->l2ad_buflist, hdr);
mutex_exit(&dev->l2ad_mtx);
- /*
- * Compute and store the buffer cksum before
- * writing. On debug the cksum is verified first.
- */
- arc_cksum_verify(hdr->b_l1hdr.b_buf);
- arc_cksum_compute(hdr->b_l1hdr.b_buf, B_TRUE);
+ (void) refcount_add_many(&dev->l2ad_alloc,
+ arc_hdr_size(hdr), hdr);
+
+ wzio = zio_write_phys(pio, dev->l2ad_vdev,
+ hdr->b_l2hdr.b_daddr, asize, to_write,
+ ZIO_CHECKSUM_OFF, NULL, hdr,
+ ZIO_PRIORITY_ASYNC_WRITE,
+ ZIO_FLAG_CANFAIL, B_FALSE);
+
+ write_lsize += HDR_GET_LSIZE(hdr);
+ DTRACE_PROBE2(l2arc__write, vdev_t *, dev->l2ad_vdev,
+ zio_t *, wzio);
+
+ write_psize += psize;
+ write_asize += asize;
+ dev->l2ad_hand += asize;
mutex_exit(hash_lock);
- write_sz += buf_sz;
+ (void) zio_nowait(wzio);
}
multilist_sublist_unlock(mls);
/* No buffers selected for writing? */
if (pio == NULL) {
- ASSERT0(write_sz);
+ ASSERT0(write_lsize);
ASSERT(!HDR_HAS_L1HDR(head));
kmem_cache_free(hdr_l2only_cache, head);
return (0);
}
- mutex_enter(&dev->l2ad_mtx);
-
- /*
- * Now start writing the buffers. We're starting at the write head
- * and work backwards, retracing the course of the buffer selector
- * loop above.
- */
- for (hdr = list_prev(&dev->l2ad_buflist, head); hdr;
- hdr = list_prev(&dev->l2ad_buflist, hdr)) {
- uint64_t buf_sz;
-
- /*
- * We rely on the L1 portion of the header below, so
- * it's invalid for this header to have been evicted out
- * of the ghost cache, prior to being written out. The
- * ARC_FLAG_L2_WRITING bit ensures this won't happen.
- */
- ASSERT(HDR_HAS_L1HDR(hdr));
-
- /*
- * We shouldn't need to lock the buffer here, since we flagged
- * it as ARC_FLAG_L2_WRITING in the previous step, but we must
- * take care to only access its L2 cache parameters. In
- * particular, hdr->l1hdr.b_buf may be invalid by now due to
- * ARC eviction.
- */
- hdr->b_l2hdr.b_daddr = dev->l2ad_hand;
-
- if ((!l2arc_nocompress && HDR_L2COMPRESS(hdr)) &&
- hdr->b_l2hdr.b_asize >= buf_compress_minsz) {
- if (l2arc_compress_buf(hdr)) {
- /*
- * If compression succeeded, enable headroom
- * boost on the next scan cycle.
- */
- *headroom_boost = B_TRUE;
- }
- }
-
- /*
- * Pick up the buffer data we had previously stashed away
- * (and now potentially also compressed).
- */
- buf_data = hdr->b_l1hdr.b_tmp_cdata;
- buf_sz = hdr->b_l2hdr.b_asize;
-
- /* Compression may have squashed the buffer to zero length. */
- if (buf_sz != 0) {
- uint64_t buf_p_sz;
-
- wzio = zio_write_phys(pio, dev->l2ad_vdev,
- dev->l2ad_hand, buf_sz, buf_data, ZIO_CHECKSUM_OFF,
- NULL, NULL, ZIO_PRIORITY_ASYNC_WRITE,
- ZIO_FLAG_CANFAIL, B_FALSE);
-
- DTRACE_PROBE2(l2arc__write, vdev_t *, dev->l2ad_vdev,
- zio_t *, wzio);
- (void) zio_nowait(wzio);
-
- write_asize += buf_sz;
- /*
- * Keep the clock hand suitably device-aligned.
- */
- buf_p_sz = vdev_psize_to_asize(dev->l2ad_vdev, buf_sz);
- write_psize += buf_p_sz;
- dev->l2ad_hand += buf_p_sz;
- }
- }
-
- mutex_exit(&dev->l2ad_mtx);
-
ASSERT3U(write_asize, <=, target_sz);
ARCSTAT_BUMP(arcstat_l2_writes_sent);
- ARCSTAT_INCR(arcstat_l2_write_bytes, write_asize);
- ARCSTAT_INCR(arcstat_l2_size, write_sz);
- ARCSTAT_INCR(arcstat_l2_asize, write_asize);
- vdev_space_update(dev->l2ad_vdev, write_asize, 0, 0);
+ ARCSTAT_INCR(arcstat_l2_write_bytes, write_psize);
+ ARCSTAT_INCR(arcstat_l2_lsize, write_lsize);
+ ARCSTAT_INCR(arcstat_l2_psize, write_psize);
+ vdev_space_update(dev->l2ad_vdev, write_psize, 0, 0);
/*
* Bump device hand to the device start if it is approaching the end.
*/
if (dev->l2ad_hand >= (dev->l2ad_end - target_sz)) {
dev->l2ad_hand = dev->l2ad_start;
- dev->l2ad_evict = dev->l2ad_start;
dev->l2ad_first = B_FALSE;
}
return (write_asize);
}
-/*
- * Compresses an L2ARC buffer.
- * The data to be compressed must be prefilled in l1hdr.b_tmp_cdata and its
- * size in l2hdr->b_asize. This routine tries to compress the data and
- * depending on the compression result there are three possible outcomes:
- * *) The buffer was incompressible. The original l2hdr contents were left
- * untouched and are ready for writing to an L2 device.
- * *) The buffer was all-zeros, so there is no need to write it to an L2
- * device. To indicate this situation b_tmp_cdata is NULL'ed, b_asize is
- * set to zero and b_compress is set to ZIO_COMPRESS_EMPTY.
- * *) Compression succeeded and b_tmp_cdata was replaced with a temporary
- * data buffer which holds the compressed data to be written, and b_asize
- * tells us how much data there is. b_compress is set to the appropriate
- * compression algorithm. Once writing is done, invoke
- * l2arc_release_cdata_buf on this l2hdr to free this temporary buffer.
- *
- * Returns B_TRUE if compression succeeded, or B_FALSE if it didn't (the
- * buffer was incompressible).
- */
-static boolean_t
-l2arc_compress_buf(arc_buf_hdr_t *hdr)
-{
- void *cdata;
- size_t csize, len, rounded;
- l2arc_buf_hdr_t *l2hdr;
-
- ASSERT(HDR_HAS_L2HDR(hdr));
-
- l2hdr = &hdr->b_l2hdr;
-
- ASSERT(HDR_HAS_L1HDR(hdr));
- ASSERT(HDR_GET_COMPRESS(hdr) == ZIO_COMPRESS_OFF);
- ASSERT(hdr->b_l1hdr.b_tmp_cdata != NULL);
-
- len = l2hdr->b_asize;
- cdata = zio_data_buf_alloc(len);
- ASSERT3P(cdata, !=, NULL);
- csize = zio_compress_data(ZIO_COMPRESS_LZ4, hdr->b_l1hdr.b_tmp_cdata,
- cdata, l2hdr->b_asize);
-
- rounded = P2ROUNDUP(csize, (size_t)SPA_MINBLOCKSIZE);
- if (rounded > csize) {
- bzero((char *)cdata + csize, rounded - csize);
- csize = rounded;
- }
-
- if (csize == 0) {
- /* zero block, indicate that there's nothing to write */
- zio_data_buf_free(cdata, len);
- HDR_SET_COMPRESS(hdr, ZIO_COMPRESS_EMPTY);
- l2hdr->b_asize = 0;
- hdr->b_l1hdr.b_tmp_cdata = NULL;
- ARCSTAT_BUMP(arcstat_l2_compress_zeros);
- return (B_TRUE);
- } else if (csize > 0 && csize < len) {
- /*
- * Compression succeeded, we'll keep the cdata around for
- * writing and release it afterwards.
- */
- HDR_SET_COMPRESS(hdr, ZIO_COMPRESS_LZ4);
- l2hdr->b_asize = csize;
- hdr->b_l1hdr.b_tmp_cdata = cdata;
- ARCSTAT_BUMP(arcstat_l2_compress_successes);
- return (B_TRUE);
- } else {
- /*
- * Compression failed, release the compressed buffer.
- * l2hdr will be left unmodified.
- */
- zio_data_buf_free(cdata, len);
- ARCSTAT_BUMP(arcstat_l2_compress_failures);
- return (B_FALSE);
- }
-}
-
-/*
- * Decompresses a zio read back from an l2arc device. On success, the
- * underlying zio's io_data buffer is overwritten by the uncompressed
- * version. On decompression error (corrupt compressed stream), the
- * zio->io_error value is set to signal an I/O error.
- *
- * Please note that the compressed data stream is not checksummed, so
- * if the underlying device is experiencing data corruption, we may feed
- * corrupt data to the decompressor, so the decompressor needs to be
- * able to handle this situation (LZ4 does).
- */
-static void
-l2arc_decompress_zio(zio_t *zio, arc_buf_hdr_t *hdr, enum zio_compress c)
-{
- uint64_t csize;
- void *cdata;
-
- ASSERT(L2ARC_IS_VALID_COMPRESS(c));
-
- if (zio->io_error != 0) {
- /*
- * An io error has occured, just restore the original io
- * size in preparation for a main pool read.
- */
- zio->io_orig_size = zio->io_size = hdr->b_size;
- return;
- }
-
- if (c == ZIO_COMPRESS_EMPTY) {
- /*
- * An empty buffer results in a null zio, which means we
- * need to fill its io_data after we're done restoring the
- * buffer's contents.
- */
- ASSERT(hdr->b_l1hdr.b_buf != NULL);
- bzero(hdr->b_l1hdr.b_buf->b_data, hdr->b_size);
- zio->io_data = zio->io_orig_data = hdr->b_l1hdr.b_buf->b_data;
- } else {
- ASSERT(zio->io_data != NULL);
- /*
- * We copy the compressed data from the start of the arc buffer
- * (the zio_read will have pulled in only what we need, the
- * rest is garbage which we will overwrite at decompression)
- * and then decompress back to the ARC data buffer. This way we
- * can minimize copying by simply decompressing back over the
- * original compressed data (rather than decompressing to an
- * aux buffer and then copying back the uncompressed buffer,
- * which is likely to be much larger).
- */
- csize = zio->io_size;
- cdata = zio_data_buf_alloc(csize);
- bcopy(zio->io_data, cdata, csize);
- if (zio_decompress_data(c, cdata, zio->io_data, csize,
- hdr->b_size) != 0)
- zio->io_error = SET_ERROR(EIO);
- zio_data_buf_free(cdata, csize);
- }
-
- /* Restore the expected uncompressed IO size. */
- zio->io_orig_size = zio->io_size = hdr->b_size;
-}
-
-/*
- * Releases the temporary b_tmp_cdata buffer in an l2arc header structure.
- * This buffer serves as a temporary holder of compressed data while
- * the buffer entry is being written to an l2arc device. Once that is
- * done, we can dispose of it.
- */
-static void
-l2arc_release_cdata_buf(arc_buf_hdr_t *hdr)
-{
- enum zio_compress comp = HDR_GET_COMPRESS(hdr);
-
- ASSERT(HDR_HAS_L1HDR(hdr));
- ASSERT(comp == ZIO_COMPRESS_OFF || L2ARC_IS_VALID_COMPRESS(comp));
-
- if (comp == ZIO_COMPRESS_OFF) {
- /*
- * In this case, b_tmp_cdata points to the same buffer
- * as the arc_buf_t's b_data field. We don't want to
- * free it, since the arc_buf_t will handle that.
- */
- hdr->b_l1hdr.b_tmp_cdata = NULL;
- } else if (comp == ZIO_COMPRESS_EMPTY) {
- /*
- * In this case, b_tmp_cdata was compressed to an empty
- * buffer, thus there's nothing to free and b_tmp_cdata
- * should have been set to NULL in l2arc_write_buffers().
- */
- ASSERT3P(hdr->b_l1hdr.b_tmp_cdata, ==, NULL);
- } else {
- /*
- * If the data was compressed, then we've allocated a
- * temporary buffer for it, so now we need to release it.
- */
- ASSERT(hdr->b_l1hdr.b_tmp_cdata != NULL);
- zio_data_buf_free(hdr->b_l1hdr.b_tmp_cdata,
- hdr->b_size);
- hdr->b_l1hdr.b_tmp_cdata = NULL;
- }
-
-}
-
/*
* This thread feeds the L2ARC at regular intervals. This is the beating
* heart of the L2ARC.
*/
static void
-l2arc_feed_thread(void)
+l2arc_feed_thread(void *unused)
{
callb_cpr_t cpr;
l2arc_dev_t *dev;
spa_t *spa;
uint64_t size, wrote;
clock_t begin, next = ddi_get_lbolt();
- boolean_t headroom_boost = B_FALSE;
fstrans_cookie_t cookie;
CALLB_CPR_INIT(&cpr, &l2arc_feed_thr_lock, callb_generic_cpr, FTAG);
cookie = spl_fstrans_mark();
while (l2arc_thread_exit == 0) {
CALLB_CPR_SAFE_BEGIN(&cpr);
- (void) cv_timedwait_interruptible(&l2arc_feed_thr_cv,
+ (void) cv_timedwait_sig(&l2arc_feed_thr_cv,
&l2arc_feed_thr_lock, next);
CALLB_CPR_SAFE_END(&cpr, &l2arc_feed_thr_lock);
next = ddi_get_lbolt() + hz;
continue;
spa = dev->l2ad_spa;
- ASSERT(spa != NULL);
+ ASSERT3P(spa, !=, NULL);
/*
* If the pool is read-only then force the feed thread to
/*
* Avoid contributing to memory pressure.
*/
- if (arc_no_grow) {
+ if (arc_reclaim_needed()) {
ARCSTAT_BUMP(arcstat_l2_abort_lowmem);
spa_config_exit(spa, SCL_L2ARC, dev);
continue;
/*
* Write ARC buffers.
*/
- wrote = l2arc_write_buffers(spa, dev, size, &headroom_boost);
+ wrote = l2arc_write_buffers(spa, dev, size);
/*
* Calculate interval between writes.
adddev->l2ad_start = VDEV_LABEL_START_SIZE;
adddev->l2ad_end = VDEV_LABEL_START_SIZE + vdev_get_min_asize(vd);
adddev->l2ad_hand = adddev->l2ad_start;
- adddev->l2ad_evict = adddev->l2ad_start;
adddev->l2ad_first = B_TRUE;
adddev->l2ad_writing = B_FALSE;
list_link_init(&adddev->l2ad_node);
offsetof(arc_buf_hdr_t, b_l2hdr.b_l2node));
vdev_space_update(vd, 0, 0, adddev->l2ad_end - adddev->l2ad_hand);
+ refcount_create(&adddev->l2ad_alloc);
/*
* Add device to global list
break;
}
}
- ASSERT(remdev != NULL);
+ ASSERT3P(remdev, !=, NULL);
/*
* Remove device from global list
l2arc_evict(remdev, 0, B_TRUE);
list_destroy(&remdev->l2ad_buflist);
mutex_destroy(&remdev->l2ad_mtx);
+ refcount_destroy(&remdev->l2ad_alloc);
kmem_free(remdev, sizeof (l2arc_dev_t));
}
return;
(void) thread_create(NULL, 0, l2arc_feed_thread, NULL, 0, &p0,
- TS_RUN, minclsyspri);
+ TS_RUN, defclsyspri);
}
void
EXPORT_SYMBOL(arc_buf_size);
EXPORT_SYMBOL(arc_write);
EXPORT_SYMBOL(arc_read);
-EXPORT_SYMBOL(arc_buf_remove_ref);
EXPORT_SYMBOL(arc_buf_info);
EXPORT_SYMBOL(arc_getbuf_func);
EXPORT_SYMBOL(arc_add_prune_callback);
EXPORT_SYMBOL(arc_remove_prune_callback);
+/* BEGIN CSTYLED */
module_param(zfs_arc_min, ulong, 0644);
MODULE_PARM_DESC(zfs_arc_min, "Min arc size");
module_param(zfs_arc_meta_limit, ulong, 0644);
MODULE_PARM_DESC(zfs_arc_meta_limit, "Meta limit for arc size");
+module_param(zfs_arc_meta_limit_percent, ulong, 0644);
+MODULE_PARM_DESC(zfs_arc_meta_limit_percent,
+ "Percent of arc size for arc meta limit");
+
module_param(zfs_arc_meta_min, ulong, 0644);
MODULE_PARM_DESC(zfs_arc_meta_min, "Min arc metadata");
module_param(zfs_arc_meta_prune, int, 0644);
MODULE_PARM_DESC(zfs_arc_meta_prune, "Meta objects to scan for prune");
-module_param(zfs_arc_meta_adjust_restarts, ulong, 0644);
+module_param(zfs_arc_meta_adjust_restarts, int, 0644);
MODULE_PARM_DESC(zfs_arc_meta_adjust_restarts,
"Limit number of restarts in arc_adjust_meta");
module_param(zfs_arc_shrink_shift, int, 0644);
MODULE_PARM_DESC(zfs_arc_shrink_shift, "log2(fraction of arc to reclaim)");
-module_param(zfs_disable_dup_eviction, int, 0644);
-MODULE_PARM_DESC(zfs_disable_dup_eviction, "disable duplicate buffer eviction");
+module_param(zfs_arc_pc_percent, uint, 0644);
+MODULE_PARM_DESC(zfs_arc_pc_percent,
+ "Percent of pagecache to reclaim arc to");
+
+module_param(zfs_arc_p_min_shift, int, 0644);
+MODULE_PARM_DESC(zfs_arc_p_min_shift, "arc_c shift to calc min/max arc_p");
module_param(zfs_arc_average_blocksize, int, 0444);
MODULE_PARM_DESC(zfs_arc_average_blocksize, "Target average block size");
-module_param(zfs_arc_memory_throttle_disable, int, 0644);
-MODULE_PARM_DESC(zfs_arc_memory_throttle_disable, "disable memory throttle");
+module_param(zfs_compressed_arc_enabled, int, 0644);
+MODULE_PARM_DESC(zfs_compressed_arc_enabled, "Disable compressed arc buffers");
module_param(zfs_arc_min_prefetch_lifespan, int, 0644);
MODULE_PARM_DESC(zfs_arc_min_prefetch_lifespan, "Min life of prefetch block");
-module_param(zfs_arc_num_sublists_per_state, int, 0644);
-MODULE_PARM_DESC(zfs_arc_num_sublists_per_state,
- "Number of sublists used in each of the ARC state lists");
-
module_param(l2arc_write_max, ulong, 0644);
MODULE_PARM_DESC(l2arc_write_max, "Max write bytes per interval");
module_param(l2arc_noprefetch, int, 0644);
MODULE_PARM_DESC(l2arc_noprefetch, "Skip caching prefetched buffers");
-module_param(l2arc_nocompress, int, 0644);
-MODULE_PARM_DESC(l2arc_nocompress, "Skip compressing L2ARC buffers");
-
module_param(l2arc_feed_again, int, 0644);
MODULE_PARM_DESC(l2arc_feed_again, "Turbo L2ARC warmup");
module_param(l2arc_norw, int, 0644);
MODULE_PARM_DESC(l2arc_norw, "No reads during writes");
+module_param(zfs_arc_lotsfree_percent, int, 0644);
+MODULE_PARM_DESC(zfs_arc_lotsfree_percent,
+ "System free memory I/O throttle in bytes");
+
+module_param(zfs_arc_sys_free, ulong, 0644);
+MODULE_PARM_DESC(zfs_arc_sys_free, "System free memory target size in bytes");
+
+module_param(zfs_arc_dnode_limit, ulong, 0644);
+MODULE_PARM_DESC(zfs_arc_dnode_limit, "Minimum bytes of dnodes in arc");
+
+module_param(zfs_arc_dnode_limit_percent, ulong, 0644);
+MODULE_PARM_DESC(zfs_arc_dnode_limit_percent,
+ "Percent of ARC meta buffers for dnodes");
+
+module_param(zfs_arc_dnode_reduce_percent, ulong, 0644);
+MODULE_PARM_DESC(zfs_arc_dnode_reduce_percent,
+ "Percentage of excess dnodes to try to unpin");
+/* END CSTYLED */
#endif
projects / mirror_zfs.git / blobdiff