ZAP: Some cleanups/micro-optimizations

- Remove custom zap_memset(), use regular memset().
- Use PANIC() instead of opaque cmn_err(CE_PANIC).
- Provide entry parameter to zap_leaf_rehash_entry().
- Reduce branching in zap_leaf_array_create() inner loop.
- Remove signedness where it should not be.

Should be no function changes.

Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #15976

diff --git a/include/sys/zap_leaf.h b/include/sys/zap_leaf.h
index ebc67c2bf465c1a4fbf122495ef8375ab91b290f..d563edd7ba59911b21351ff8b52b09f001bbb3e1 100644 (file)
--- a/include/sys/zap_leaf.h
+++ b/include/sys/zap_leaf.h
@@ -47,7 +47,7 @@ struct zap_stats;
  * entries - header space (2*chunksize)
  */
 #define        ZAP_LEAF_NUMCHUNKS_BS(bs) \
-       (((1<<(bs)) - 2*ZAP_LEAF_HASH_NUMENTRIES_BS(bs)) / \
+       (((1U << (bs)) - 2 * ZAP_LEAF_HASH_NUMENTRIES_BS(bs)) / \
        ZAP_LEAF_CHUNKSIZE - 2)
 
 #define        ZAP_LEAF_NUMCHUNKS(l) (ZAP_LEAF_NUMCHUNKS_BS(((l)->l_bs)))
@@ -80,7 +80,7 @@ struct zap_stats;
  * chunks per entry (3).
  */
 #define        ZAP_LEAF_HASH_SHIFT_BS(bs) ((bs) - 5)
-#define        ZAP_LEAF_HASH_NUMENTRIES_BS(bs) (1 << ZAP_LEAF_HASH_SHIFT_BS(bs))
+#define        ZAP_LEAF_HASH_NUMENTRIES_BS(bs) (1U << ZAP_LEAF_HASH_SHIFT_BS(bs))
 #define        ZAP_LEAF_HASH_SHIFT(l) (ZAP_LEAF_HASH_SHIFT_BS(((l)->l_bs)))
 #define        ZAP_LEAF_HASH_NUMENTRIES(l) (ZAP_LEAF_HASH_NUMENTRIES_BS(((l)->l_bs)))
 
@@ -163,7 +163,7 @@ typedef struct zap_leaf {
        dmu_buf_user_t l_dbu;
        krwlock_t l_rwlock;
        uint64_t l_blkid;               /* 1<<ZAP_BLOCK_SHIFT byte block off */
-       int l_bs;                       /* block size shift */
+       uint_t l_bs;                    /* block size shift */
        dmu_buf_t *l_dbuf;
 } zap_leaf_t;
 
@@ -243,7 +243,7 @@ extern boolean_t zap_entry_normalization_conflict(zap_entry_handle_t *zeh,
  */
 
 extern void zap_leaf_init(zap_leaf_t *l, boolean_t sort);
-extern void zap_leaf_byteswap(zap_leaf_phys_t *buf, int len);
+extern void zap_leaf_byteswap(zap_leaf_phys_t *buf, size_t len);
 extern void zap_leaf_split(zap_leaf_t *l, zap_leaf_t *nl, boolean_t sort);
 extern void zap_leaf_stats(struct zap *zap, zap_leaf_t *l,
     struct zap_stats *zs);

diff --git a/module/zfs/zap_leaf.c b/module/zfs/zap_leaf.c
index e6afb1c58c956a4ec020c1be3e961f52fbcf9aef..032aca92695e506d666d80040e624016ca91b8fe 100644 (file)
--- a/module/zfs/zap_leaf.c
+++ b/module/zfs/zap_leaf.c
@@ -41,7 +41,8 @@
 #include <sys/zap_leaf.h>
 #include <sys/arc.h>
 
-static uint16_t *zap_leaf_rehash_entry(zap_leaf_t *l, uint16_t entry);
+static uint16_t *zap_leaf_rehash_entry(zap_leaf_t *l, struct zap_leaf_entry *le,
+    uint16_t entry);
 
 #define        CHAIN_END 0xffff /* end of the chunk chain */
 
@@ -52,16 +53,6 @@ static uint16_t *zap_leaf_rehash_entry(zap_leaf_t *l, uint16_t entry);
 
 #define        LEAF_HASH_ENTPTR(l, h)  (&zap_leaf_phys(l)->l_hash[LEAF_HASH(l, h)])
 
-static void
-zap_memset(void *a, int c, size_t n)
-{
-       char *cp = a;
-       char *cpend = cp + n;
-
-       while (cp < cpend)
-               *cp++ = c;
-}
-
 static void
 stv(int len, void *addr, uint64_t value)
 {
@@ -79,7 +70,7 @@ stv(int len, void *addr, uint64_t value)
                *(uint64_t *)addr = value;
                return;
        default:
-               cmn_err(CE_PANIC, "bad int len %d", len);
+               PANIC("bad int len %d", len);
        }
 }
 
@@ -96,13 +87,13 @@ ldv(int len, const void *addr)
        case 8:
                return (*(uint64_t *)addr);
        default:
-               cmn_err(CE_PANIC, "bad int len %d", len);
+               PANIC("bad int len %d", len);
        }
        return (0xFEEDFACEDEADBEEFULL);
 }
 
 void
-zap_leaf_byteswap(zap_leaf_phys_t *buf, int size)
+zap_leaf_byteswap(zap_leaf_phys_t *buf, size_t size)
 {
        zap_leaf_t l;
        dmu_buf_t l_dbuf;
@@ -119,10 +110,10 @@ zap_leaf_byteswap(zap_leaf_phys_t *buf, int size)
        buf->l_hdr.lh_prefix_len =      BSWAP_16(buf->l_hdr.lh_prefix_len);
        buf->l_hdr.lh_freelist =        BSWAP_16(buf->l_hdr.lh_freelist);
 
-       for (int i = 0; i < ZAP_LEAF_HASH_NUMENTRIES(&l); i++)
+       for (uint_t i = 0; i < ZAP_LEAF_HASH_NUMENTRIES(&l); i++)
                buf->l_hash[i] = BSWAP_16(buf->l_hash[i]);
 
-       for (int i = 0; i < ZAP_LEAF_NUMCHUNKS(&l); i++) {
+       for (uint_t i = 0; i < ZAP_LEAF_NUMCHUNKS(&l); i++) {
                zap_leaf_chunk_t *lc = &ZAP_LEAF_CHUNK(&l, i);
                struct zap_leaf_entry *le;
 
@@ -160,11 +151,11 @@ void
 zap_leaf_init(zap_leaf_t *l, boolean_t sort)
 {
        l->l_bs = highbit64(l->l_dbuf->db_size) - 1;
-       zap_memset(&zap_leaf_phys(l)->l_hdr, 0,
+       memset(&zap_leaf_phys(l)->l_hdr, 0,
            sizeof (struct zap_leaf_header));
-       zap_memset(zap_leaf_phys(l)->l_hash, CHAIN_END,
+       memset(zap_leaf_phys(l)->l_hash, CHAIN_END,
            2*ZAP_LEAF_HASH_NUMENTRIES(l));
-       for (int i = 0; i < ZAP_LEAF_NUMCHUNKS(l); i++) {
+       for (uint_t i = 0; i < ZAP_LEAF_NUMCHUNKS(l); i++) {
                ZAP_LEAF_CHUNK(l, i).l_free.lf_type = ZAP_CHUNK_FREE;
                ZAP_LEAF_CHUNK(l, i).l_free.lf_next = i+1;
        }
@@ -185,7 +176,7 @@ zap_leaf_chunk_alloc(zap_leaf_t *l)
 {
        ASSERT(zap_leaf_phys(l)->l_hdr.lh_nfree > 0);
 
-       int chunk = zap_leaf_phys(l)->l_hdr.lh_freelist;
+       uint_t chunk = zap_leaf_phys(l)->l_hdr.lh_freelist;
        ASSERT3U(chunk, <, ZAP_LEAF_NUMCHUNKS(l));
        ASSERT3U(ZAP_LEAF_CHUNK(l, chunk).l_free.lf_type, ==, ZAP_CHUNK_FREE);
 
@@ -223,28 +214,29 @@ zap_leaf_array_create(zap_leaf_t *l, const char *buf,
 {
        uint16_t chunk_head;
        uint16_t *chunkp = &chunk_head;
-       int byten = 0;
+       int byten = integer_size;
        uint64_t value = 0;
        int shift = (integer_size - 1) * 8;
        int len = num_integers;
 
        ASSERT3U(num_integers * integer_size, <=, ZAP_MAXVALUELEN);
 
+       if (len > 0)
+               value = ldv(integer_size, buf);
        while (len > 0) {
                uint16_t chunk = zap_leaf_chunk_alloc(l);
                struct zap_leaf_array *la = &ZAP_LEAF_CHUNK(l, chunk).l_array;
 
                la->la_type = ZAP_CHUNK_ARRAY;
                for (int i = 0; i < ZAP_LEAF_ARRAY_BYTES; i++) {
-                       if (byten == 0)
-                               value = ldv(integer_size, buf);
                        la->la_array[i] = value >> shift;
                        value <<= 8;
-                       if (++byten == integer_size) {
-                               byten = 0;
-                               buf += integer_size;
+                       if (--byten == 0) {
                                if (--len == 0)
                                        break;
+                               byten = integer_size;
+                               buf += integer_size;
+                               value = ldv(integer_size, buf);
                        }
                }
 
@@ -264,7 +256,7 @@ zap_leaf_array_free(zap_leaf_t *l, uint16_t *chunkp)
        *chunkp = CHAIN_END;
 
        while (chunk != CHAIN_END) {
-               int nextchunk = ZAP_LEAF_CHUNK(l, chunk).l_array.la_next;
+               uint_t nextchunk = ZAP_LEAF_CHUNK(l, chunk).l_array.la_next;
                ASSERT3U(ZAP_LEAF_CHUNK(l, chunk).l_array.la_type, ==,
                    ZAP_CHUNK_ARRAY);
                zap_leaf_chunk_free(l, chunk);
@@ -333,7 +325,7 @@ zap_leaf_array_read(zap_leaf_t *l, uint16_t chunk,
 
 static boolean_t
 zap_leaf_array_match(zap_leaf_t *l, zap_name_t *zn,
-    int chunk, int array_numints)
+    uint_t chunk, int array_numints)
 {
        int bseen = 0;
 
@@ -562,7 +554,7 @@ zap_entry_create(zap_leaf_t *l, zap_name_t *zn, uint32_t cd,
 
        uint64_t valuelen = integer_size * num_integers;
 
-       int numchunks = 1 + ZAP_LEAF_ARRAY_NCHUNKS(zn->zn_key_orig_numints *
+       uint_t numchunks = 1 + ZAP_LEAF_ARRAY_NCHUNKS(zn->zn_key_orig_numints *
            zn->zn_key_intlen) + ZAP_LEAF_ARRAY_NCHUNKS(valuelen);
        if (numchunks > ZAP_LEAF_NUMCHUNKS(l))
                return (SET_ERROR(E2BIG));
@@ -624,7 +616,7 @@ zap_entry_create(zap_leaf_t *l, zap_name_t *zn, uint32_t cd,
 
        /* link it into the hash chain */
        /* XXX if we did the search above, we could just use that */
-       uint16_t *chunkp = zap_leaf_rehash_entry(l, chunk);
+       uint16_t *chunkp = zap_leaf_rehash_entry(l, le, chunk);
 
        zap_leaf_phys(l)->l_hdr.lh_nentries++;
 
@@ -687,9 +679,8 @@ zap_entry_normalization_conflict(zap_entry_handle_t *zeh, zap_name_t *zn,
  */
 
 static uint16_t *
-zap_leaf_rehash_entry(zap_leaf_t *l, uint16_t entry)
+zap_leaf_rehash_entry(zap_leaf_t *l, struct zap_leaf_entry *le, uint16_t entry)
 {
-       struct zap_leaf_entry *le = ZAP_LEAF_ENTRY(l, entry);
        struct zap_leaf_entry *le2;
        uint16_t *chunkp;
 
@@ -722,7 +713,7 @@ zap_leaf_transfer_array(zap_leaf_t *l, uint16_t chunk, zap_leaf_t *nl)
                    &ZAP_LEAF_CHUNK(nl, nchunk).l_array;
                struct zap_leaf_array *la =
                    &ZAP_LEAF_CHUNK(l, chunk).l_array;
-               int nextchunk = la->la_next;
+               uint_t nextchunk = la->la_next;
 
                ASSERT3U(chunk, <, ZAP_LEAF_NUMCHUNKS(l));
                ASSERT3U(nchunk, <, ZAP_LEAF_NUMCHUNKS(l));
@@ -739,7 +730,7 @@ zap_leaf_transfer_array(zap_leaf_t *l, uint16_t chunk, zap_leaf_t *nl)
 }
 
 static void
-zap_leaf_transfer_entry(zap_leaf_t *l, int entry, zap_leaf_t *nl)
+zap_leaf_transfer_entry(zap_leaf_t *l, uint_t entry, zap_leaf_t *nl)
 {
        struct zap_leaf_entry *le = ZAP_LEAF_ENTRY(l, entry);
        ASSERT3U(le->le_type, ==, ZAP_CHUNK_ENTRY);
@@ -748,7 +739,7 @@ zap_leaf_transfer_entry(zap_leaf_t *l, int entry, zap_leaf_t *nl)
        struct zap_leaf_entry *nle = ZAP_LEAF_ENTRY(nl, chunk);
        *nle = *le; /* structure assignment */
 
-       (void) zap_leaf_rehash_entry(nl, chunk);
+       (void) zap_leaf_rehash_entry(nl, nle, chunk);
 
        nle->le_name_chunk = zap_leaf_transfer_array(l, le->le_name_chunk, nl);
        nle->le_value_chunk =
@@ -766,7 +757,7 @@ zap_leaf_transfer_entry(zap_leaf_t *l, int entry, zap_leaf_t *nl)
 void
 zap_leaf_split(zap_leaf_t *l, zap_leaf_t *nl, boolean_t sort)
 {
-       int bit = 64 - 1 - zap_leaf_phys(l)->l_hdr.lh_prefix_len;
+       uint_t bit = 64 - 1 - zap_leaf_phys(l)->l_hdr.lh_prefix_len;
 
        /* set new prefix and prefix_len */
        zap_leaf_phys(l)->l_hdr.lh_prefix <<= 1;
@@ -777,7 +768,7 @@ zap_leaf_split(zap_leaf_t *l, zap_leaf_t *nl, boolean_t sort)
            zap_leaf_phys(l)->l_hdr.lh_prefix_len;
 
        /* break existing hash chains */
-       zap_memset(zap_leaf_phys(l)->l_hash, CHAIN_END,
+       memset(zap_leaf_phys(l)->l_hash, CHAIN_END,
            2*ZAP_LEAF_HASH_NUMENTRIES(l));
 
        if (sort)
@@ -792,7 +783,7 @@ zap_leaf_split(zap_leaf_t *l, zap_leaf_t *nl, boolean_t sort)
         * but this accesses memory more sequentially, and when we're
         * called, the block is usually pretty full.
         */
-       for (int i = 0; i < ZAP_LEAF_NUMCHUNKS(l); i++) {
+       for (uint_t i = 0; i < ZAP_LEAF_NUMCHUNKS(l); i++) {
                struct zap_leaf_entry *le = ZAP_LEAF_ENTRY(l, i);
                if (le->le_type != ZAP_CHUNK_ENTRY)
                        continue;
@@ -800,14 +791,14 @@ zap_leaf_split(zap_leaf_t *l, zap_leaf_t *nl, boolean_t sort)
                if (le->le_hash & (1ULL << bit))
                        zap_leaf_transfer_entry(l, i, nl);
                else
-                       (void) zap_leaf_rehash_entry(l, i);
+                       (void) zap_leaf_rehash_entry(l, le, i);
        }
 }
 
 void
 zap_leaf_stats(zap_t *zap, zap_leaf_t *l, zap_stats_t *zs)
 {
-       int n = zap_f_phys(zap)->zap_ptrtbl.zt_shift -
+       uint_t n = zap_f_phys(zap)->zap_ptrtbl.zt_shift -
            zap_leaf_phys(l)->l_hdr.lh_prefix_len;
        n = MIN(n, ZAP_HISTOGRAM_SIZE-1);
        zs->zs_leafs_with_2n_pointers[n]++;
@@ -823,9 +814,9 @@ zap_leaf_stats(zap_t *zap, zap_leaf_t *l, zap_stats_t *zs)
        n = MIN(n, ZAP_HISTOGRAM_SIZE-1);
        zs->zs_blocks_n_tenths_full[n]++;
 
-       for (int i = 0; i < ZAP_LEAF_HASH_NUMENTRIES(l); i++) {
-               int nentries = 0;
-               int chunk = zap_leaf_phys(l)->l_hash[i];
+       for (uint_t i = 0; i < ZAP_LEAF_HASH_NUMENTRIES(l); i++) {
+               uint_t nentries = 0;
+               uint_t chunk = zap_leaf_phys(l)->l_hash[i];
 
                while (chunk != CHAIN_END) {
                        struct zap_leaf_entry *le =