+++ /dev/null
-/*
- * Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC.
- * Copyright (C) 2007 The Regents of the University of California.
- * Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
- * Written by Brian Behlendorf <behlendorf1@llnl.gov>.
- * UCRL-CODE-235197
- *
- * This file is part of the SPL, Solaris Porting Layer.
- * For details, see <http://zfsonlinux.org/>.
- *
- * The SPL is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the
- * Free Software Foundation; either version 2 of the License, or (at your
- * option) any later version.
- *
- * The SPL is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
- * for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with the SPL. If not, see <http://www.gnu.org/licenses/>.
- */
-
-#include <sys/debug.h>
-#include <sys/sysmacros.h>
-#include <sys/kmem.h>
-#include <sys/vmem.h>
-#include <linux/mm.h>
-#include <linux/ratelimit.h>
-
-/*
- * As a general rule kmem_alloc() allocations should be small, preferably
- * just a few pages since they must by physically contiguous. Therefore, a
- * rate limited warning will be printed to the console for any kmem_alloc()
- * which exceeds a reasonable threshold.
- *
- * The default warning threshold is set to sixteen pages but capped at 64K to
- * accommodate systems using large pages. This value was selected to be small
- * enough to ensure the largest allocations are quickly noticed and fixed.
- * But large enough to avoid logging any warnings when a allocation size is
- * larger than optimal but not a serious concern. Since this value is tunable,
- * developers are encouraged to set it lower when testing so any new largish
- * allocations are quickly caught. These warnings may be disabled by setting
- * the threshold to zero.
- */
-unsigned int spl_kmem_alloc_warn = MIN(16 * PAGE_SIZE, 64 * 1024);
-module_param(spl_kmem_alloc_warn, uint, 0644);
-MODULE_PARM_DESC(spl_kmem_alloc_warn,
- "Warning threshold in bytes for a kmem_alloc()");
-EXPORT_SYMBOL(spl_kmem_alloc_warn);
-
-/*
- * Large kmem_alloc() allocations will fail if they exceed KMALLOC_MAX_SIZE.
- * Allocations which are marginally smaller than this limit may succeed but
- * should still be avoided due to the expense of locating a contiguous range
- * of free pages. Therefore, a maximum kmem size with reasonable safely
- * margin of 4x is set. Kmem_alloc() allocations larger than this maximum
- * will quickly fail. Vmem_alloc() allocations less than or equal to this
- * value will use kmalloc(), but shift to vmalloc() when exceeding this value.
- */
-unsigned int spl_kmem_alloc_max = (KMALLOC_MAX_SIZE >> 2);
-module_param(spl_kmem_alloc_max, uint, 0644);
-MODULE_PARM_DESC(spl_kmem_alloc_max,
- "Maximum size in bytes for a kmem_alloc()");
-EXPORT_SYMBOL(spl_kmem_alloc_max);
-
-int
-kmem_debugging(void)
-{
- return (0);
-}
-EXPORT_SYMBOL(kmem_debugging);
-
-char *
-kmem_vasprintf(const char *fmt, va_list ap)
-{
- va_list aq;
- char *ptr;
-
- do {
- va_copy(aq, ap);
- ptr = kvasprintf(kmem_flags_convert(KM_SLEEP), fmt, aq);
- va_end(aq);
- } while (ptr == NULL);
-
- return (ptr);
-}
-EXPORT_SYMBOL(kmem_vasprintf);
-
-char *
-kmem_asprintf(const char *fmt, ...)
-{
- va_list ap;
- char *ptr;
-
- do {
- va_start(ap, fmt);
- ptr = kvasprintf(kmem_flags_convert(KM_SLEEP), fmt, ap);
- va_end(ap);
- } while (ptr == NULL);
-
- return (ptr);
-}
-EXPORT_SYMBOL(kmem_asprintf);
-
-static char *
-__strdup(const char *str, int flags)
-{
- char *ptr;
- int n;
-
- n = strlen(str);
- ptr = kmalloc(n + 1, kmem_flags_convert(flags));
- if (ptr)
- memcpy(ptr, str, n + 1);
-
- return (ptr);
-}
-
-char *
-strdup(const char *str)
-{
- return (__strdup(str, KM_SLEEP));
-}
-EXPORT_SYMBOL(strdup);
-
-void
-strfree(char *str)
-{
- kfree(str);
-}
-EXPORT_SYMBOL(strfree);
-
-/*
- * Limit the number of large allocation stack traces dumped to not more than
- * 5 every 60 seconds to prevent denial-of-service attacks from debug code.
- */
-DEFINE_RATELIMIT_STATE(kmem_alloc_ratelimit_state, 60 * HZ, 5);
-
-/*
- * General purpose unified implementation of kmem_alloc(). It is an
- * amalgamation of Linux and Illumos allocator design. It should never be
- * exported to ensure that code using kmem_alloc()/kmem_zalloc() remains
- * relatively portable. Consumers may only access this function through
- * wrappers that enforce the common flags to ensure portability.
- */
-inline void *
-spl_kmem_alloc_impl(size_t size, int flags, int node)
-{
- gfp_t lflags = kmem_flags_convert(flags);
- int use_vmem = 0;
- void *ptr;
-
- /*
- * Log abnormally large allocations and rate limit the console output.
- * Allocations larger than spl_kmem_alloc_warn should be performed
- * through the vmem_alloc()/vmem_zalloc() interfaces.
- */
- if ((spl_kmem_alloc_warn > 0) && (size > spl_kmem_alloc_warn) &&
- !(flags & KM_VMEM) && __ratelimit(&kmem_alloc_ratelimit_state)) {
- printk(KERN_WARNING
- "Large kmem_alloc(%lu, 0x%x), please file an issue at:\n"
- "https://github.com/zfsonlinux/zfs/issues/new\n",
- (unsigned long)size, flags);
- dump_stack();
- }
-
- /*
- * Use a loop because kmalloc_node() can fail when GFP_KERNEL is used
- * unlike kmem_alloc() with KM_SLEEP on Illumos.
- */
- do {
- /*
- * Calling kmalloc_node() when the size >= spl_kmem_alloc_max
- * is unsafe. This must fail for all for kmem_alloc() and
- * kmem_zalloc() callers.
- *
- * For vmem_alloc() and vmem_zalloc() callers it is permissible
- * to use __vmalloc(). However, in general use of __vmalloc()
- * is strongly discouraged because a global lock must be
- * acquired. Contention on this lock can significantly
- * impact performance so frequently manipulating the virtual
- * address space is strongly discouraged.
- */
- if ((size > spl_kmem_alloc_max) || use_vmem) {
- if (flags & KM_VMEM) {
- ptr = __vmalloc(size, lflags, PAGE_KERNEL);
- } else {
- return (NULL);
- }
- } else {
- ptr = kmalloc_node(size, lflags, node);
- }
-
- if (likely(ptr) || (flags & KM_NOSLEEP))
- return (ptr);
-
- /*
- * For vmem_alloc() and vmem_zalloc() callers retry immediately
- * using __vmalloc() which is unlikely to fail.
- */
- if ((flags & KM_VMEM) && (use_vmem == 0)) {
- use_vmem = 1;
- continue;
- }
-
- if (unlikely(__ratelimit(&kmem_alloc_ratelimit_state))) {
- printk(KERN_WARNING
- "Possible memory allocation deadlock: "
- "size=%lu lflags=0x%x",
- (unsigned long)size, lflags);
- dump_stack();
- }
-
- /*
- * Use cond_resched() instead of congestion_wait() to avoid
- * deadlocking systems where there are no block devices.
- */
- cond_resched();
- } while (1);
-
- return (NULL);
-}
-
-inline void
-spl_kmem_free_impl(const void *buf, size_t size)
-{
- if (is_vmalloc_addr(buf))
- vfree(buf);
- else
- kfree(buf);
-}
-
-/*
- * Memory allocation and accounting for kmem_* * style allocations. When
- * DEBUG_KMEM is enabled the total memory allocated will be tracked and
- * any memory leaked will be reported during module unload.
- *
- * ./configure --enable-debug-kmem
- */
-#ifdef DEBUG_KMEM
-
-/* Shim layer memory accounting */
-#ifdef HAVE_ATOMIC64_T
-atomic64_t kmem_alloc_used = ATOMIC64_INIT(0);
-unsigned long long kmem_alloc_max = 0;
-#else /* HAVE_ATOMIC64_T */
-atomic_t kmem_alloc_used = ATOMIC_INIT(0);
-unsigned long long kmem_alloc_max = 0;
-#endif /* HAVE_ATOMIC64_T */
-
-EXPORT_SYMBOL(kmem_alloc_used);
-EXPORT_SYMBOL(kmem_alloc_max);
-
-inline void *
-spl_kmem_alloc_debug(size_t size, int flags, int node)
-{
- void *ptr;
-
- ptr = spl_kmem_alloc_impl(size, flags, node);
- if (ptr) {
- kmem_alloc_used_add(size);
- if (unlikely(kmem_alloc_used_read() > kmem_alloc_max))
- kmem_alloc_max = kmem_alloc_used_read();
- }
-
- return (ptr);
-}
-
-inline void
-spl_kmem_free_debug(const void *ptr, size_t size)
-{
- kmem_alloc_used_sub(size);
- spl_kmem_free_impl(ptr, size);
-}
-
-/*
- * When DEBUG_KMEM_TRACKING is enabled not only will total bytes be tracked
- * but also the location of every alloc and free. When the SPL module is
- * unloaded a list of all leaked addresses and where they were allocated
- * will be dumped to the console. Enabling this feature has a significant
- * impact on performance but it makes finding memory leaks straight forward.
- *
- * Not surprisingly with debugging enabled the xmem_locks are very highly
- * contended particularly on xfree(). If we want to run with this detailed
- * debugging enabled for anything other than debugging we need to minimize
- * the contention by moving to a lock per xmem_table entry model.
- *
- * ./configure --enable-debug-kmem-tracking
- */
-#ifdef DEBUG_KMEM_TRACKING
-
-#include <linux/hash.h>
-#include <linux/ctype.h>
-
-#define KMEM_HASH_BITS 10
-#define KMEM_TABLE_SIZE (1 << KMEM_HASH_BITS)
-
-typedef struct kmem_debug {
- struct hlist_node kd_hlist; /* Hash node linkage */
- struct list_head kd_list; /* List of all allocations */
- void *kd_addr; /* Allocation pointer */
- size_t kd_size; /* Allocation size */
- const char *kd_func; /* Allocation function */
- int kd_line; /* Allocation line */
-} kmem_debug_t;
-
-static spinlock_t kmem_lock;
-static struct hlist_head kmem_table[KMEM_TABLE_SIZE];
-static struct list_head kmem_list;
-
-static kmem_debug_t *
-kmem_del_init(spinlock_t *lock, struct hlist_head *table,
- int bits, const void *addr)
-{
- struct hlist_head *head;
- struct hlist_node *node;
- struct kmem_debug *p;
- unsigned long flags;
-
- spin_lock_irqsave(lock, flags);
-
- head = &table[hash_ptr((void *)addr, bits)];
- hlist_for_each(node, head) {
- p = list_entry(node, struct kmem_debug, kd_hlist);
- if (p->kd_addr == addr) {
- hlist_del_init(&p->kd_hlist);
- list_del_init(&p->kd_list);
- spin_unlock_irqrestore(lock, flags);
- return (p);
- }
- }
-
- spin_unlock_irqrestore(lock, flags);
-
- return (NULL);
-}
-
-inline void *
-spl_kmem_alloc_track(size_t size, int flags,
- const char *func, int line, int node)
-{
- void *ptr = NULL;
- kmem_debug_t *dptr;
- unsigned long irq_flags;
-
- dptr = kmalloc(sizeof (kmem_debug_t), kmem_flags_convert(flags));
- if (dptr == NULL)
- return (NULL);
-
- dptr->kd_func = __strdup(func, flags);
- if (dptr->kd_func == NULL) {
- kfree(dptr);
- return (NULL);
- }
-
- ptr = spl_kmem_alloc_debug(size, flags, node);
- if (ptr == NULL) {
- kfree(dptr->kd_func);
- kfree(dptr);
- return (NULL);
- }
-
- INIT_HLIST_NODE(&dptr->kd_hlist);
- INIT_LIST_HEAD(&dptr->kd_list);
-
- dptr->kd_addr = ptr;
- dptr->kd_size = size;
- dptr->kd_line = line;
-
- spin_lock_irqsave(&kmem_lock, irq_flags);
- hlist_add_head(&dptr->kd_hlist,
- &kmem_table[hash_ptr(ptr, KMEM_HASH_BITS)]);
- list_add_tail(&dptr->kd_list, &kmem_list);
- spin_unlock_irqrestore(&kmem_lock, irq_flags);
-
- return (ptr);
-}
-
-inline void
-spl_kmem_free_track(const void *ptr, size_t size)
-{
- kmem_debug_t *dptr;
-
- /* Ignore NULL pointer since we haven't tracked it at all*/
- if (ptr == NULL)
- return;
-
- /* Must exist in hash due to kmem_alloc() */
- dptr = kmem_del_init(&kmem_lock, kmem_table, KMEM_HASH_BITS, ptr);
- ASSERT3P(dptr, !=, NULL);
- ASSERT3S(dptr->kd_size, ==, size);
-
- kfree(dptr->kd_func);
- kfree(dptr);
-
- spl_kmem_free_debug(ptr, size);
-}
-#endif /* DEBUG_KMEM_TRACKING */
-#endif /* DEBUG_KMEM */
-
-/*
- * Public kmem_alloc(), kmem_zalloc() and kmem_free() interfaces.
- */
-void *
-spl_kmem_alloc(size_t size, int flags, const char *func, int line)
-{
- ASSERT0(flags & ~KM_PUBLIC_MASK);
-
-#if !defined(DEBUG_KMEM)
- return (spl_kmem_alloc_impl(size, flags, NUMA_NO_NODE));
-#elif !defined(DEBUG_KMEM_TRACKING)
- return (spl_kmem_alloc_debug(size, flags, NUMA_NO_NODE));
-#else
- return (spl_kmem_alloc_track(size, flags, func, line, NUMA_NO_NODE));
-#endif
-}
-EXPORT_SYMBOL(spl_kmem_alloc);
-
-void *
-spl_kmem_zalloc(size_t size, int flags, const char *func, int line)
-{
- ASSERT0(flags & ~KM_PUBLIC_MASK);
-
- flags |= KM_ZERO;
-
-#if !defined(DEBUG_KMEM)
- return (spl_kmem_alloc_impl(size, flags, NUMA_NO_NODE));
-#elif !defined(DEBUG_KMEM_TRACKING)
- return (spl_kmem_alloc_debug(size, flags, NUMA_NO_NODE));
-#else
- return (spl_kmem_alloc_track(size, flags, func, line, NUMA_NO_NODE));
-#endif
-}
-EXPORT_SYMBOL(spl_kmem_zalloc);
-
-void
-spl_kmem_free(const void *buf, size_t size)
-{
-#if !defined(DEBUG_KMEM)
- return (spl_kmem_free_impl(buf, size));
-#elif !defined(DEBUG_KMEM_TRACKING)
- return (spl_kmem_free_debug(buf, size));
-#else
- return (spl_kmem_free_track(buf, size));
-#endif
-}
-EXPORT_SYMBOL(spl_kmem_free);
-
-#if defined(DEBUG_KMEM) && defined(DEBUG_KMEM_TRACKING)
-static char *
-spl_sprintf_addr(kmem_debug_t *kd, char *str, int len, int min)
-{
- int size = ((len - 1) < kd->kd_size) ? (len - 1) : kd->kd_size;
- int i, flag = 1;
-
- ASSERT(str != NULL && len >= 17);
- memset(str, 0, len);
-
- /*
- * Check for a fully printable string, and while we are at
- * it place the printable characters in the passed buffer.
- */
- for (i = 0; i < size; i++) {
- str[i] = ((char *)(kd->kd_addr))[i];
- if (isprint(str[i])) {
- continue;
- } else {
- /*
- * Minimum number of printable characters found
- * to make it worthwhile to print this as ascii.
- */
- if (i > min)
- break;
-
- flag = 0;
- break;
- }
- }
-
- if (!flag) {
- sprintf(str, "%02x%02x%02x%02x%02x%02x%02x%02x",
- *((uint8_t *)kd->kd_addr),
- *((uint8_t *)kd->kd_addr + 2),
- *((uint8_t *)kd->kd_addr + 4),
- *((uint8_t *)kd->kd_addr + 6),
- *((uint8_t *)kd->kd_addr + 8),
- *((uint8_t *)kd->kd_addr + 10),
- *((uint8_t *)kd->kd_addr + 12),
- *((uint8_t *)kd->kd_addr + 14));
- }
-
- return (str);
-}
-
-static int
-spl_kmem_init_tracking(struct list_head *list, spinlock_t *lock, int size)
-{
- int i;
-
- spin_lock_init(lock);
- INIT_LIST_HEAD(list);
-
- for (i = 0; i < size; i++)
- INIT_HLIST_HEAD(&kmem_table[i]);
-
- return (0);
-}
-
-static void
-spl_kmem_fini_tracking(struct list_head *list, spinlock_t *lock)
-{
- unsigned long flags;
- kmem_debug_t *kd;
- char str[17];
-
- spin_lock_irqsave(lock, flags);
- if (!list_empty(list))
- printk(KERN_WARNING "%-16s %-5s %-16s %s:%s\n", "address",
- "size", "data", "func", "line");
-
- list_for_each_entry(kd, list, kd_list)
- printk(KERN_WARNING "%p %-5d %-16s %s:%d\n", kd->kd_addr,
- (int)kd->kd_size, spl_sprintf_addr(kd, str, 17, 8),
- kd->kd_func, kd->kd_line);
-
- spin_unlock_irqrestore(lock, flags);
-}
-#endif /* DEBUG_KMEM && DEBUG_KMEM_TRACKING */
-
-int
-spl_kmem_init(void)
-{
-#ifdef DEBUG_KMEM
- kmem_alloc_used_set(0);
-
-#ifdef DEBUG_KMEM_TRACKING
- spl_kmem_init_tracking(&kmem_list, &kmem_lock, KMEM_TABLE_SIZE);
-#endif /* DEBUG_KMEM_TRACKING */
-#endif /* DEBUG_KMEM */
-
- return (0);
-}
-
-void
-spl_kmem_fini(void)
-{
-#ifdef DEBUG_KMEM
- /*
- * Display all unreclaimed memory addresses, including the
- * allocation size and the first few bytes of what's located
- * at that address to aid in debugging. Performance is not
- * a serious concern here since it is module unload time.
- */
- if (kmem_alloc_used_read() != 0)
- printk(KERN_WARNING "kmem leaked %ld/%llu bytes\n",
- (unsigned long)kmem_alloc_used_read(), kmem_alloc_max);
-
-#ifdef DEBUG_KMEM_TRACKING
- spl_kmem_fini_tracking(&kmem_list, &kmem_lock);
-#endif /* DEBUG_KMEM_TRACKING */
-#endif /* DEBUG_KMEM */
-}
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