#include <linux/mempolicy.h>
#include <linux/ctype.h>
#include <linux/kallsyms.h>
+#include <linux/memory.h>
/*
* Lock order:
*
* Overloading of page flags that are otherwise used for LRU management.
*
- * PageActive The slab is used as a cpu cache. Allocations
- * may be performed from the slab. The slab is not
- * on any slab list and cannot be moved onto one.
+ * PageActive The slab is frozen and exempt from list processing.
+ * This means that the slab is dedicated to a purpose
+ * such as satisfying allocations for a specific
+ * processor. Objects may be freed in the slab while
+ * it is frozen but slab_free will then skip the usual
+ * list operations. It is up to the processor holding
+ * the slab to integrate the slab into the slab lists
+ * when the slab is no longer needed.
+ *
+ * One use of this flag is to mark slabs that are
+ * used for allocations. Then such a slab becomes a cpu
+ * slab. The cpu slab may be equipped with an additional
+ * freelist that allows lockless access to
+ * free objects in addition to the regular freelist
+ * that requires the slab lock.
*
* PageError Slab requires special handling due to debug
* options set. This moves slab handling out of
- * the fast path.
+ * the fast path and disables lockless freelists.
*/
+#define FROZEN (1 << PG_active)
+
+#ifdef CONFIG_SLUB_DEBUG
+#define SLABDEBUG (1 << PG_error)
+#else
+#define SLABDEBUG 0
+#endif
+
+static inline int SlabFrozen(struct page *page)
+{
+ return page->flags & FROZEN;
+}
+
+static inline void SetSlabFrozen(struct page *page)
+{
+ page->flags |= FROZEN;
+}
+
+static inline void ClearSlabFrozen(struct page *page)
+{
+ page->flags &= ~FROZEN;
+}
+
+static inline int SlabDebug(struct page *page)
+{
+ return page->flags & SLABDEBUG;
+}
+
+static inline void SetSlabDebug(struct page *page)
+{
+ page->flags |= SLABDEBUG;
+}
+
+static inline void ClearSlabDebug(struct page *page)
+{
+ page->flags &= ~SLABDEBUG;
+}
+
/*
* Issues still to be resolved:
*
- * - The per cpu array is updated for each new slab and and is a remote
- * cacheline for most nodes. This could become a bouncing cacheline given
- * enough frequent updates. There are 16 pointers in a cacheline, so at
- * max 16 cpus could compete for the cacheline which may be okay.
- *
* - Support PAGE_ALLOC_DEBUG. Should be easy to do.
*
* - Variable sizing of the per node arrays
* Mininum number of partial slabs. These will be left on the partial
* lists even if they are empty. kmem_cache_shrink may reclaim them.
*/
-#define MIN_PARTIAL 2
+#define MIN_PARTIAL 5
/*
* Maximum number of desirable partial slabs.
#endif
/* Internal SLUB flags */
-#define __OBJECT_POISON 0x80000000 /* Poison object */
+#define __OBJECT_POISON 0x80000000 /* Poison object */
+#define __SYSFS_ADD_DEFERRED 0x40000000 /* Not yet visible via sysfs */
/* Not all arches define cache_line_size */
#ifndef cache_line_size
/* A list of all slab caches on the system */
static DECLARE_RWSEM(slub_lock);
-LIST_HEAD(slab_caches);
+static LIST_HEAD(slab_caches);
+
+/*
+ * Tracking user of a slab.
+ */
+struct track {
+ void *addr; /* Called from address */
+ int cpu; /* Was running on cpu */
+ int pid; /* Pid context */
+ unsigned long when; /* When did the operation occur */
+};
+
+enum track_item { TRACK_ALLOC, TRACK_FREE };
-#ifdef CONFIG_SYSFS
+#if defined(CONFIG_SYSFS) && defined(CONFIG_SLUB_DEBUG)
static int sysfs_slab_add(struct kmem_cache *);
static int sysfs_slab_alias(struct kmem_cache *, const char *);
static void sysfs_slab_remove(struct kmem_cache *);
#else
-static int sysfs_slab_add(struct kmem_cache *s) { return 0; }
-static int sysfs_slab_alias(struct kmem_cache *s, const char *p) { return 0; }
-static void sysfs_slab_remove(struct kmem_cache *s) {}
+static inline int sysfs_slab_add(struct kmem_cache *s) { return 0; }
+static inline int sysfs_slab_alias(struct kmem_cache *s, const char *p)
+ { return 0; }
+static inline void sysfs_slab_remove(struct kmem_cache *s) {}
#endif
/********************************************************************
#endif
}
+static inline struct kmem_cache_cpu *get_cpu_slab(struct kmem_cache *s, int cpu)
+{
+#ifdef CONFIG_SMP
+ return s->cpu_slab[cpu];
+#else
+ return &s->cpu_slab;
+#endif
+}
+
+static inline int check_valid_pointer(struct kmem_cache *s,
+ struct page *page, const void *object)
+{
+ void *base;
+
+ if (!object)
+ return 1;
+
+ base = page_address(page);
+ if (object < base || object >= base + s->objects * s->size ||
+ (object - base) % s->size) {
+ return 0;
+ }
+
+ return 1;
+}
+
+/*
+ * Slow version of get and set free pointer.
+ *
+ * This version requires touching the cache lines of kmem_cache which
+ * we avoid to do in the fast alloc free paths. There we obtain the offset
+ * from the page struct.
+ */
+static inline void *get_freepointer(struct kmem_cache *s, void *object)
+{
+ return *(void **)(object + s->offset);
+}
+
+static inline void set_freepointer(struct kmem_cache *s, void *object, void *fp)
+{
+ *(void **)(object + s->offset) = fp;
+}
+
+/* Loop over all objects in a slab */
+#define for_each_object(__p, __s, __addr) \
+ for (__p = (__addr); __p < (__addr) + (__s)->objects * (__s)->size;\
+ __p += (__s)->size)
+
+/* Scan freelist */
+#define for_each_free_object(__p, __s, __free) \
+ for (__p = (__free); __p; __p = get_freepointer((__s), __p))
+
+/* Determine object index from a given position */
+static inline int slab_index(void *p, struct kmem_cache *s, void *addr)
+{
+ return (p - addr) / s->size;
+}
+
+#ifdef CONFIG_SLUB_DEBUG
+/*
+ * Debug settings:
+ */
+#ifdef CONFIG_SLUB_DEBUG_ON
+static int slub_debug = DEBUG_DEFAULT_FLAGS;
+#else
+static int slub_debug;
+#endif
+
+static char *slub_debug_slabs;
+
/*
* Object debugging
*/
for (i = 0; i < length; i++) {
if (newline) {
- printk(KERN_ERR "%10s 0x%p: ", text, addr + i);
+ printk(KERN_ERR "%8s 0x%p: ", text, addr + i);
newline = 0;
}
printk(" %02x", addr[i]);
}
}
-/*
- * Slow version of get and set free pointer.
- *
- * This version requires touching the cache lines of kmem_cache which
- * we avoid to do in the fast alloc free paths. There we obtain the offset
- * from the page struct.
- */
-static void *get_freepointer(struct kmem_cache *s, void *object)
-{
- return *(void **)(object + s->offset);
-}
-
-static void set_freepointer(struct kmem_cache *s, void *object, void *fp)
-{
- *(void **)(object + s->offset) = fp;
-}
-
-/*
- * Tracking user of a slab.
- */
-struct track {
- void *addr; /* Called from address */
- int cpu; /* Was running on cpu */
- int pid; /* Pid context */
- unsigned long when; /* When did the operation occur */
-};
-
-enum track_item { TRACK_ALLOC, TRACK_FREE };
-
static struct track *get_track(struct kmem_cache *s, void *object,
enum track_item alloc)
{
static void init_tracking(struct kmem_cache *s, void *object)
{
- if (s->flags & SLAB_STORE_USER) {
- set_track(s, object, TRACK_FREE, NULL);
- set_track(s, object, TRACK_ALLOC, NULL);
- }
+ if (!(s->flags & SLAB_STORE_USER))
+ return;
+
+ set_track(s, object, TRACK_FREE, NULL);
+ set_track(s, object, TRACK_ALLOC, NULL);
}
static void print_track(const char *s, struct track *t)
if (!t->addr)
return;
- printk(KERN_ERR "%s: ", s);
+ printk(KERN_ERR "INFO: %s in ", s);
__print_symbol("%s", (unsigned long)t->addr);
- printk(" jiffies_ago=%lu cpu=%u pid=%d\n", jiffies - t->when, t->cpu, t->pid);
+ printk(" age=%lu cpu=%u pid=%d\n", jiffies - t->when, t->cpu, t->pid);
+}
+
+static void print_tracking(struct kmem_cache *s, void *object)
+{
+ if (!(s->flags & SLAB_STORE_USER))
+ return;
+
+ print_track("Allocated", get_track(s, object, TRACK_ALLOC));
+ print_track("Freed", get_track(s, object, TRACK_FREE));
+}
+
+static void print_page_info(struct page *page)
+{
+ printk(KERN_ERR "INFO: Slab 0x%p used=%u fp=0x%p flags=0x%04lx\n",
+ page, page->inuse, page->freelist, page->flags);
+
+}
+
+static void slab_bug(struct kmem_cache *s, char *fmt, ...)
+{
+ va_list args;
+ char buf[100];
+
+ va_start(args, fmt);
+ vsnprintf(buf, sizeof(buf), fmt, args);
+ va_end(args);
+ printk(KERN_ERR "========================================"
+ "=====================================\n");
+ printk(KERN_ERR "BUG %s: %s\n", s->name, buf);
+ printk(KERN_ERR "----------------------------------------"
+ "-------------------------------------\n\n");
}
-static void print_trailer(struct kmem_cache *s, u8 *p)
+static void slab_fix(struct kmem_cache *s, char *fmt, ...)
+{
+ va_list args;
+ char buf[100];
+
+ va_start(args, fmt);
+ vsnprintf(buf, sizeof(buf), fmt, args);
+ va_end(args);
+ printk(KERN_ERR "FIX %s: %s\n", s->name, buf);
+}
+
+static void print_trailer(struct kmem_cache *s, struct page *page, u8 *p)
{
unsigned int off; /* Offset of last byte */
+ u8 *addr = page_address(page);
+
+ print_tracking(s, p);
+
+ print_page_info(page);
+
+ printk(KERN_ERR "INFO: Object 0x%p @offset=%tu fp=0x%p\n\n",
+ p, p - addr, get_freepointer(s, p));
+
+ if (p > addr + 16)
+ print_section("Bytes b4", p - 16, 16);
+
+ print_section("Object", p, min(s->objsize, 128));
if (s->flags & SLAB_RED_ZONE)
print_section("Redzone", p + s->objsize,
s->inuse - s->objsize);
- printk(KERN_ERR "FreePointer 0x%p -> 0x%p\n",
- p + s->offset,
- get_freepointer(s, p));
-
if (s->offset)
off = s->offset + sizeof(void *);
else
off = s->inuse;
- if (s->flags & SLAB_STORE_USER) {
- print_track("Last alloc", get_track(s, p, TRACK_ALLOC));
- print_track("Last free ", get_track(s, p, TRACK_FREE));
+ if (s->flags & SLAB_STORE_USER)
off += 2 * sizeof(struct track);
- }
if (off != s->size)
/* Beginning of the filler is the free pointer */
- print_section("Filler", p + off, s->size - off);
+ print_section("Padding", p + off, s->size - off);
+
+ dump_stack();
}
static void object_err(struct kmem_cache *s, struct page *page,
u8 *object, char *reason)
{
- u8 *addr = page_address(page);
-
- printk(KERN_ERR "*** SLUB %s: %s@0x%p slab 0x%p\n",
- s->name, reason, object, page);
- printk(KERN_ERR " offset=%tu flags=0x%04lx inuse=%u freelist=0x%p\n",
- object - addr, page->flags, page->inuse, page->freelist);
- if (object > addr + 16)
- print_section("Bytes b4", object - 16, 16);
- print_section("Object", object, min(s->objsize, 128));
- print_trailer(s, object);
- dump_stack();
+ slab_bug(s, reason);
+ print_trailer(s, page, object);
}
-static void slab_err(struct kmem_cache *s, struct page *page, char *reason, ...)
+static void slab_err(struct kmem_cache *s, struct page *page, char *fmt, ...)
{
va_list args;
char buf[100];
- va_start(args, reason);
- vsnprintf(buf, sizeof(buf), reason, args);
+ va_start(args, fmt);
+ vsnprintf(buf, sizeof(buf), fmt, args);
va_end(args);
- printk(KERN_ERR "*** SLUB %s: %s in slab @0x%p\n", s->name, buf,
- page);
+ slab_bug(s, fmt);
+ print_page_info(page);
dump_stack();
}
s->inuse - s->objsize);
}
-static int check_bytes(u8 *start, unsigned int value, unsigned int bytes)
+static u8 *check_bytes(u8 *start, unsigned int value, unsigned int bytes)
{
while (bytes) {
if (*start != (u8)value)
- return 0;
+ return start;
start++;
bytes--;
}
- return 1;
+ return NULL;
}
-static inline int check_valid_pointer(struct kmem_cache *s,
- struct page *page, const void *object)
+static void restore_bytes(struct kmem_cache *s, char *message, u8 data,
+ void *from, void *to)
{
- void *base;
+ slab_fix(s, "Restoring 0x%p-0x%p=0x%x\n", from, to - 1, data);
+ memset(from, data, to - from);
+}
- if (!object)
+static int check_bytes_and_report(struct kmem_cache *s, struct page *page,
+ u8 *object, char *what,
+ u8* start, unsigned int value, unsigned int bytes)
+{
+ u8 *fault;
+ u8 *end;
+
+ fault = check_bytes(start, value, bytes);
+ if (!fault)
return 1;
- base = page_address(page);
- if (object < base || object >= base + s->objects * s->size ||
- (object - base) % s->size) {
- return 0;
- }
+ end = start + bytes;
+ while (end > fault && end[-1] == value)
+ end--;
- return 1;
+ slab_bug(s, "%s overwritten", what);
+ printk(KERN_ERR "INFO: 0x%p-0x%p. First byte 0x%x instead of 0x%x\n",
+ fault, end - 1, fault[0], value);
+ print_trailer(s, page, object);
+
+ restore_bytes(s, what, value, fault, end);
+ return 0;
}
/*
* may be used with merged slabcaches.
*/
-static void restore_bytes(struct kmem_cache *s, char *message, u8 data,
- void *from, void *to)
-{
- printk(KERN_ERR "@@@ SLUB %s: Restoring %s (0x%x) from 0x%p-0x%p\n",
- s->name, message, data, from, to - 1);
- memset(from, data, to - from);
-}
-
static int check_pad_bytes(struct kmem_cache *s, struct page *page, u8 *p)
{
unsigned long off = s->inuse; /* The end of info */
if (s->size == off)
return 1;
- if (check_bytes(p + off, POISON_INUSE, s->size - off))
- return 1;
-
- object_err(s, page, p, "Object padding check fails");
-
- /*
- * Restore padding
- */
- restore_bytes(s, "object padding", POISON_INUSE, p + off, p + s->size);
- return 0;
+ return check_bytes_and_report(s, page, p, "Object padding",
+ p + off, POISON_INUSE, s->size - off);
}
static int slab_pad_check(struct kmem_cache *s, struct page *page)
{
- u8 *p;
- int length, remainder;
+ u8 *start;
+ u8 *fault;
+ u8 *end;
+ int length;
+ int remainder;
if (!(s->flags & SLAB_POISON))
return 1;
- p = page_address(page);
+ start = page_address(page);
+ end = start + (PAGE_SIZE << s->order);
length = s->objects * s->size;
- remainder = (PAGE_SIZE << s->order) - length;
+ remainder = end - (start + length);
if (!remainder)
return 1;
- if (!check_bytes(p + length, POISON_INUSE, remainder)) {
- slab_err(s, page, "Padding check failed");
- restore_bytes(s, "slab padding", POISON_INUSE, p + length,
- p + length + remainder);
- return 0;
- }
- return 1;
+ fault = check_bytes(start + length, POISON_INUSE, remainder);
+ if (!fault)
+ return 1;
+ while (end > fault && end[-1] == POISON_INUSE)
+ end--;
+
+ slab_err(s, page, "Padding overwritten. 0x%p-0x%p", fault, end - 1);
+ print_section("Padding", start, length);
+
+ restore_bytes(s, "slab padding", POISON_INUSE, start, end);
+ return 0;
}
static int check_object(struct kmem_cache *s, struct page *page,
unsigned int red =
active ? SLUB_RED_ACTIVE : SLUB_RED_INACTIVE;
- if (!check_bytes(endobject, red, s->inuse - s->objsize)) {
- object_err(s, page, object,
- active ? "Redzone Active" : "Redzone Inactive");
- restore_bytes(s, "redzone", red,
- endobject, object + s->inuse);
+ if (!check_bytes_and_report(s, page, object, "Redzone",
+ endobject, red, s->inuse - s->objsize))
return 0;
- }
} else {
- if ((s->flags & SLAB_POISON) && s->objsize < s->inuse &&
- !check_bytes(endobject, POISON_INUSE,
- s->inuse - s->objsize)) {
- object_err(s, page, p, "Alignment padding check fails");
- /*
- * Fix it so that there will not be another report.
- *
- * Hmmm... We may be corrupting an object that now expects
- * to be longer than allowed.
- */
- restore_bytes(s, "alignment padding", POISON_INUSE,
- endobject, object + s->inuse);
- }
+ if ((s->flags & SLAB_POISON) && s->objsize < s->inuse)
+ check_bytes_and_report(s, page, p, "Alignment padding", endobject,
+ POISON_INUSE, s->inuse - s->objsize);
}
if (s->flags & SLAB_POISON) {
if (!active && (s->flags & __OBJECT_POISON) &&
- (!check_bytes(p, POISON_FREE, s->objsize - 1) ||
- p[s->objsize - 1] != POISON_END)) {
-
- object_err(s, page, p, "Poison check failed");
- restore_bytes(s, "Poison", POISON_FREE,
- p, p + s->objsize -1);
- restore_bytes(s, "Poison", POISON_END,
- p + s->objsize - 1, p + s->objsize);
+ (!check_bytes_and_report(s, page, p, "Poison", p,
+ POISON_FREE, s->objsize - 1) ||
+ !check_bytes_and_report(s, page, p, "Poison",
+ p + s->objsize -1, POISON_END, 1)))
return 0;
- }
/*
* check_pad_bytes cleans up on its own.
*/
VM_BUG_ON(!irqs_disabled());
if (!PageSlab(page)) {
- slab_err(s, page, "Not a valid slab page flags=%lx "
- "mapping=0x%p count=%d", page->flags, page->mapping,
- page_count(page));
- return 0;
- }
- if (page->offset * sizeof(void *) != s->offset) {
- slab_err(s, page, "Corrupted offset %lu flags=0x%lx "
- "mapping=0x%p count=%d",
- (unsigned long)(page->offset * sizeof(void *)),
- page->flags,
- page->mapping,
- page_count(page));
+ slab_err(s, page, "Not a valid slab page");
return 0;
}
if (page->inuse > s->objects) {
- slab_err(s, page, "inuse %u > max %u @0x%p flags=%lx "
- "mapping=0x%p count=%d",
- s->name, page->inuse, s->objects, page->flags,
- page->mapping, page_count(page));
+ slab_err(s, page, "inuse %u > max %u",
+ s->name, page->inuse, s->objects);
return 0;
}
/* Slab_pad_check fixes things up after itself */
set_freepointer(s, object, NULL);
break;
} else {
- slab_err(s, page, "Freepointer 0x%p corrupt",
- fp);
+ slab_err(s, page, "Freepointer corrupt");
page->freelist = NULL;
page->inuse = s->objects;
- printk(KERN_ERR "@@@ SLUB %s: Freelist "
- "cleared. Slab 0x%p\n",
- s->name, page);
+ slab_fix(s, "Freelist cleared");
return 0;
}
break;
if (page->inuse != s->objects - nr) {
slab_err(s, page, "Wrong object count. Counter is %d but "
- "counted were %d", s, page, page->inuse,
- s->objects - nr);
+ "counted were %d", page->inuse, s->objects - nr);
page->inuse = s->objects - nr;
- printk(KERN_ERR "@@@ SLUB %s: Object count adjusted. "
- "Slab @0x%p\n", s->name, page);
+ slab_fix(s, "Object count adjusted.");
}
return search == NULL;
}
+static void trace(struct kmem_cache *s, struct page *page, void *object, int alloc)
+{
+ if (s->flags & SLAB_TRACE) {
+ printk(KERN_INFO "TRACE %s %s 0x%p inuse=%d fp=0x%p\n",
+ s->name,
+ alloc ? "alloc" : "free",
+ object, page->inuse,
+ page->freelist);
+
+ if (!alloc)
+ print_section("Object", (void *)object, s->objsize);
+
+ dump_stack();
+ }
+}
+
/*
* Tracking of fully allocated slabs for debugging purposes.
*/
spin_unlock(&n->list_lock);
}
-static int alloc_object_checks(struct kmem_cache *s, struct page *page,
- void *object)
+static void setup_object_debug(struct kmem_cache *s, struct page *page,
+ void *object)
+{
+ if (!(s->flags & (SLAB_STORE_USER|SLAB_RED_ZONE|__OBJECT_POISON)))
+ return;
+
+ init_object(s, object, 0);
+ init_tracking(s, object);
+}
+
+static int alloc_debug_processing(struct kmem_cache *s, struct page *page,
+ void *object, void *addr)
{
if (!check_slab(s, page))
goto bad;
if (object && !on_freelist(s, page, object)) {
- slab_err(s, page, "Object 0x%p already allocated", object);
+ object_err(s, page, object, "Object already allocated");
goto bad;
}
goto bad;
}
- if (!object)
- return 1;
-
- if (!check_object(s, page, object, 0))
+ if (object && !check_object(s, page, object, 0))
goto bad;
+ /* Success perform special debug activities for allocs */
+ if (s->flags & SLAB_STORE_USER)
+ set_track(s, object, TRACK_ALLOC, addr);
+ trace(s, page, object, 1);
+ init_object(s, object, 1);
return 1;
+
bad:
if (PageSlab(page)) {
/*
* to avoid issues in the future. Marking all objects
* as used avoids touching the remaining objects.
*/
- printk(KERN_ERR "@@@ SLUB: %s slab 0x%p. Marking all objects used.\n",
- s->name, page);
+ slab_fix(s, "Marking all objects used");
page->inuse = s->objects;
page->freelist = NULL;
- /* Fix up fields that may be corrupted */
- page->offset = s->offset / sizeof(void *);
}
return 0;
}
-static int free_object_checks(struct kmem_cache *s, struct page *page,
- void *object)
+static int free_debug_processing(struct kmem_cache *s, struct page *page,
+ void *object, void *addr)
{
if (!check_slab(s, page))
goto fail;
}
if (on_freelist(s, page, object)) {
- slab_err(s, page, "Object 0x%p already free", object);
+ object_err(s, page, object, "Object already free");
goto fail;
}
dump_stack();
}
else
- slab_err(s, page, "object at 0x%p belongs "
- "to slab %s", object, page->slab->name);
+ object_err(s, page, object,
+ "page slab pointer corrupt.");
goto fail;
}
+
+ /* Special debug activities for freeing objects */
+ if (!SlabFrozen(page) && !page->freelist)
+ remove_full(s, page);
+ if (s->flags & SLAB_STORE_USER)
+ set_track(s, object, TRACK_FREE, addr);
+ trace(s, page, object, 0);
+ init_object(s, object, 0);
return 1;
+
fail:
- printk(KERN_ERR "@@@ SLUB: %s slab 0x%p object at 0x%p not freed.\n",
- s->name, page, object);
+ slab_fix(s, "Object at 0x%p not freed", object);
return 0;
}
-/*
- * Slab allocation and freeing
- */
-static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node)
+static int __init setup_slub_debug(char *str)
{
- struct page * page;
- int pages = 1 << s->order;
-
- if (s->order)
- flags |= __GFP_COMP;
+ slub_debug = DEBUG_DEFAULT_FLAGS;
+ if (*str++ != '=' || !*str)
+ /*
+ * No options specified. Switch on full debugging.
+ */
+ goto out;
- if (s->flags & SLAB_CACHE_DMA)
- flags |= SLUB_DMA;
+ if (*str == ',')
+ /*
+ * No options but restriction on slabs. This means full
+ * debugging for slabs matching a pattern.
+ */
+ goto check_slabs;
- if (node == -1)
+ slub_debug = 0;
+ if (*str == '-')
+ /*
+ * Switch off all debugging measures.
+ */
+ goto out;
+
+ /*
+ * Determine which debug features should be switched on
+ */
+ for ( ;*str && *str != ','; str++) {
+ switch (tolower(*str)) {
+ case 'f':
+ slub_debug |= SLAB_DEBUG_FREE;
+ break;
+ case 'z':
+ slub_debug |= SLAB_RED_ZONE;
+ break;
+ case 'p':
+ slub_debug |= SLAB_POISON;
+ break;
+ case 'u':
+ slub_debug |= SLAB_STORE_USER;
+ break;
+ case 't':
+ slub_debug |= SLAB_TRACE;
+ break;
+ default:
+ printk(KERN_ERR "slub_debug option '%c' "
+ "unknown. skipped\n",*str);
+ }
+ }
+
+check_slabs:
+ if (*str == ',')
+ slub_debug_slabs = str + 1;
+out:
+ return 1;
+}
+
+__setup("slub_debug", setup_slub_debug);
+
+static unsigned long kmem_cache_flags(unsigned long objsize,
+ unsigned long flags, const char *name,
+ void (*ctor)(struct kmem_cache *, void *))
+{
+ /*
+ * The page->offset field is only 16 bit wide. This is an offset
+ * in units of words from the beginning of an object. If the slab
+ * size is bigger then we cannot move the free pointer behind the
+ * object anymore.
+ *
+ * On 32 bit platforms the limit is 256k. On 64bit platforms
+ * the limit is 512k.
+ *
+ * Debugging or ctor may create a need to move the free
+ * pointer. Fail if this happens.
+ */
+ if (objsize >= 65535 * sizeof(void *)) {
+ BUG_ON(flags & (SLAB_RED_ZONE | SLAB_POISON |
+ SLAB_STORE_USER | SLAB_DESTROY_BY_RCU));
+ BUG_ON(ctor);
+ } else {
+ /*
+ * Enable debugging if selected on the kernel commandline.
+ */
+ if (slub_debug && (!slub_debug_slabs ||
+ strncmp(slub_debug_slabs, name,
+ strlen(slub_debug_slabs)) == 0))
+ flags |= slub_debug;
+ }
+
+ return flags;
+}
+#else
+static inline void setup_object_debug(struct kmem_cache *s,
+ struct page *page, void *object) {}
+
+static inline int alloc_debug_processing(struct kmem_cache *s,
+ struct page *page, void *object, void *addr) { return 0; }
+
+static inline int free_debug_processing(struct kmem_cache *s,
+ struct page *page, void *object, void *addr) { return 0; }
+
+static inline int slab_pad_check(struct kmem_cache *s, struct page *page)
+ { return 1; }
+static inline int check_object(struct kmem_cache *s, struct page *page,
+ void *object, int active) { return 1; }
+static inline void add_full(struct kmem_cache_node *n, struct page *page) {}
+static inline unsigned long kmem_cache_flags(unsigned long objsize,
+ unsigned long flags, const char *name,
+ void (*ctor)(struct kmem_cache *, void *))
+{
+ return flags;
+}
+#define slub_debug 0
+#endif
+/*
+ * Slab allocation and freeing
+ */
+static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node)
+{
+ struct page * page;
+ int pages = 1 << s->order;
+
+ if (s->order)
+ flags |= __GFP_COMP;
+
+ if (s->flags & SLAB_CACHE_DMA)
+ flags |= SLUB_DMA;
+
+ if (s->flags & SLAB_RECLAIM_ACCOUNT)
+ flags |= __GFP_RECLAIMABLE;
+
+ if (node == -1)
page = alloc_pages(flags, s->order);
else
page = alloc_pages_node(node, flags, s->order);
static void setup_object(struct kmem_cache *s, struct page *page,
void *object)
{
- if (PageError(page)) {
- init_object(s, object, 0);
- init_tracking(s, object);
- }
-
+ setup_object_debug(s, page, object);
if (unlikely(s->ctor))
- s->ctor(object, s, SLAB_CTOR_CONSTRUCTOR);
+ s->ctor(s, object);
}
static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node)
struct page *page;
struct kmem_cache_node *n;
void *start;
- void *end;
void *last;
void *p;
- BUG_ON(flags & ~(GFP_DMA | GFP_LEVEL_MASK));
+ BUG_ON(flags & GFP_SLAB_BUG_MASK);
- if (flags & __GFP_WAIT)
- local_irq_enable();
-
- page = allocate_slab(s, flags & GFP_LEVEL_MASK, node);
+ page = allocate_slab(s,
+ flags & (GFP_RECLAIM_MASK | GFP_CONSTRAINT_MASK), node);
if (!page)
goto out;
n = get_node(s, page_to_nid(page));
if (n)
atomic_long_inc(&n->nr_slabs);
- page->offset = s->offset / sizeof(void *);
page->slab = s;
page->flags |= 1 << PG_slab;
if (s->flags & (SLAB_DEBUG_FREE | SLAB_RED_ZONE | SLAB_POISON |
SLAB_STORE_USER | SLAB_TRACE))
- page->flags |= 1 << PG_error;
+ SetSlabDebug(page);
start = page_address(page);
- end = start + s->objects * s->size;
if (unlikely(s->flags & SLAB_POISON))
memset(start, POISON_INUSE, PAGE_SIZE << s->order);
last = start;
- for (p = start + s->size; p < end; p += s->size) {
+ for_each_object(p, s, start) {
setup_object(s, page, last);
set_freepointer(s, last, p);
last = p;
page->freelist = start;
page->inuse = 0;
out:
- if (flags & __GFP_WAIT)
- local_irq_disable();
return page;
}
{
int pages = 1 << s->order;
- if (unlikely(PageError(page) || s->dtor)) {
- void *start = page_address(page);
- void *end = start + (pages << PAGE_SHIFT);
+ if (unlikely(SlabDebug(page))) {
void *p;
slab_pad_check(s, page);
- for (p = start; p <= end - s->size; p += s->size) {
- if (s->dtor)
- s->dtor(p, s, 0);
+ for_each_object(p, s, page_address(page))
check_object(s, page, p, 0);
- }
+ ClearSlabDebug(page);
}
mod_zone_page_state(page_zone(page),
NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE,
- pages);
- page->mapping = NULL;
__free_pages(page, s->order);
}
atomic_long_dec(&n->nr_slabs);
reset_page_mapcount(page);
- page->flags &= ~(1 << PG_slab | 1 << PG_error);
+ __ClearPageSlab(page);
free_slab(s, page);
}
*
* Must hold list_lock.
*/
-static int lock_and_del_slab(struct kmem_cache_node *n, struct page *page)
+static inline int lock_and_freeze_slab(struct kmem_cache_node *n, struct page *page)
{
if (slab_trylock(page)) {
list_del(&page->lru);
n->nr_partial--;
+ SetSlabFrozen(page);
return 1;
}
return 0;
spin_lock(&n->list_lock);
list_for_each_entry(page, &n->partial, lru)
- if (lock_and_del_slab(n, page))
+ if (lock_and_freeze_slab(n, page))
goto out;
page = NULL;
out:
*
* On exit the slab lock will have been dropped.
*/
-static void putback_slab(struct kmem_cache *s, struct page *page)
+static void unfreeze_slab(struct kmem_cache *s, struct page *page)
{
struct kmem_cache_node *n = get_node(s, page_to_nid(page));
+ ClearSlabFrozen(page);
if (page->inuse) {
if (page->freelist)
add_partial(n, page);
- else if (PageError(page) && (s->flags & SLAB_STORE_USER))
+ else if (SlabDebug(page) && (s->flags & SLAB_STORE_USER))
add_full(n, page);
slab_unlock(page);
/*
* Remove the cpu slab
*/
-static void deactivate_slab(struct kmem_cache *s, struct page *page, int cpu)
+static void deactivate_slab(struct kmem_cache *s, struct kmem_cache_cpu *c)
{
- s->cpu_slab[cpu] = NULL;
- ClearPageActive(page);
+ struct page *page = c->page;
+ /*
+ * Merge cpu freelist into freelist. Typically we get here
+ * because both freelists are empty. So this is unlikely
+ * to occur.
+ */
+ while (unlikely(c->freelist)) {
+ void **object;
- putback_slab(s, page);
+ /* Retrieve object from cpu_freelist */
+ object = c->freelist;
+ c->freelist = c->freelist[c->offset];
+
+ /* And put onto the regular freelist */
+ object[c->offset] = page->freelist;
+ page->freelist = object;
+ page->inuse--;
+ }
+ c->page = NULL;
+ unfreeze_slab(s, page);
}
-static void flush_slab(struct kmem_cache *s, struct page *page, int cpu)
+static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c)
{
- slab_lock(page);
- deactivate_slab(s, page, cpu);
+ slab_lock(c->page);
+ deactivate_slab(s, c);
}
/*
* Flush cpu slab.
* Called from IPI handler with interrupts disabled.
*/
-static void __flush_cpu_slab(struct kmem_cache *s, int cpu)
+static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu)
{
- struct page *page = s->cpu_slab[cpu];
+ struct kmem_cache_cpu *c = get_cpu_slab(s, cpu);
- if (likely(page))
- flush_slab(s, page, cpu);
+ if (likely(c && c->page))
+ flush_slab(s, c);
}
static void flush_cpu_slab(void *d)
{
struct kmem_cache *s = d;
- int cpu = smp_processor_id();
- __flush_cpu_slab(s, cpu);
+ __flush_cpu_slab(s, smp_processor_id());
}
static void flush_all(struct kmem_cache *s)
}
/*
- * slab_alloc is optimized to only modify two cachelines on the fast path
- * (aside from the stack):
+ * Check if the objects in a per cpu structure fit numa
+ * locality expectations.
+ */
+static inline int node_match(struct kmem_cache_cpu *c, int node)
+{
+#ifdef CONFIG_NUMA
+ if (node != -1 && c->node != node)
+ return 0;
+#endif
+ return 1;
+}
+
+/*
+ * Slow path. The lockless freelist is empty or we need to perform
+ * debugging duties.
*
- * 1. The page struct
- * 2. The first cacheline of the object to be allocated.
+ * Interrupts are disabled.
*
- * The only other cache lines that are read (apart from code) is the
- * per cpu array in the kmem_cache struct.
+ * Processing is still very fast if new objects have been freed to the
+ * regular freelist. In that case we simply take over the regular freelist
+ * as the lockless freelist and zap the regular freelist.
*
- * Fastpath is not possible if we need to get a new slab or have
- * debugging enabled (which means all slabs are marked with PageError)
+ * If that is not working then we fall back to the partial lists. We take the
+ * first element of the freelist as the object to allocate now and move the
+ * rest of the freelist to the lockless freelist.
+ *
+ * And if we were unable to get a new slab from the partial slab lists then
+ * we need to allocate a new slab. This is slowest path since we may sleep.
*/
-static void *slab_alloc(struct kmem_cache *s,
- gfp_t gfpflags, int node, void *addr)
+static void *__slab_alloc(struct kmem_cache *s,
+ gfp_t gfpflags, int node, void *addr, struct kmem_cache_cpu *c)
{
- struct page *page;
void **object;
- unsigned long flags;
- int cpu;
+ struct page *new;
- local_irq_save(flags);
- cpu = smp_processor_id();
- page = s->cpu_slab[cpu];
- if (!page)
+ if (!c->page)
goto new_slab;
- slab_lock(page);
- if (unlikely(node != -1 && page_to_nid(page) != node))
+ slab_lock(c->page);
+ if (unlikely(!node_match(c, node)))
goto another_slab;
-redo:
- object = page->freelist;
+load_freelist:
+ object = c->page->freelist;
if (unlikely(!object))
goto another_slab;
- if (unlikely(PageError(page)))
+ if (unlikely(SlabDebug(c->page)))
goto debug;
-have_object:
- page->inuse++;
- page->freelist = object[page->offset];
- slab_unlock(page);
- local_irq_restore(flags);
+ object = c->page->freelist;
+ c->freelist = object[c->offset];
+ c->page->inuse = s->objects;
+ c->page->freelist = NULL;
+ c->node = page_to_nid(c->page);
+ slab_unlock(c->page);
return object;
another_slab:
- deactivate_slab(s, page, cpu);
+ deactivate_slab(s, c);
new_slab:
- page = get_partial(s, gfpflags, node);
- if (likely(page)) {
-have_slab:
- s->cpu_slab[cpu] = page;
- SetPageActive(page);
- goto redo;
- }
-
- page = new_slab(s, gfpflags, node);
- if (page) {
- cpu = smp_processor_id();
- if (s->cpu_slab[cpu]) {
- /*
- * Someone else populated the cpu_slab while we
- * enabled interrupts, or we have gotten scheduled
- * on another cpu. The page may not be on the
- * requested node even if __GFP_THISNODE was
- * specified. So we need to recheck.
- */
- if (node == -1 ||
- page_to_nid(s->cpu_slab[cpu]) == node) {
- /*
- * Current cpuslab is acceptable and we
- * want the current one since its cache hot
- */
- discard_slab(s, page);
- page = s->cpu_slab[cpu];
- slab_lock(page);
- goto redo;
- }
- /* New slab does not fit our expectations */
- flush_slab(s, s->cpu_slab[cpu], cpu);
- }
- slab_lock(page);
- goto have_slab;
+ new = get_partial(s, gfpflags, node);
+ if (new) {
+ c->page = new;
+ goto load_freelist;
+ }
+
+ if (gfpflags & __GFP_WAIT)
+ local_irq_enable();
+
+ new = new_slab(s, gfpflags, node);
+
+ if (gfpflags & __GFP_WAIT)
+ local_irq_disable();
+
+ if (new) {
+ c = get_cpu_slab(s, smp_processor_id());
+ if (c->page)
+ flush_slab(s, c);
+ slab_lock(new);
+ SetSlabFrozen(new);
+ c->page = new;
+ goto load_freelist;
}
- local_irq_restore(flags);
return NULL;
debug:
- if (!alloc_object_checks(s, page, object))
+ object = c->page->freelist;
+ if (!alloc_debug_processing(s, c->page, object, addr))
goto another_slab;
- if (s->flags & SLAB_STORE_USER)
- set_track(s, object, TRACK_ALLOC, addr);
- if (s->flags & SLAB_TRACE) {
- printk(KERN_INFO "TRACE %s alloc 0x%p inuse=%d fp=0x%p\n",
- s->name, object, page->inuse,
- page->freelist);
- dump_stack();
+
+ c->page->inuse++;
+ c->page->freelist = object[c->offset];
+ c->node = -1;
+ slab_unlock(c->page);
+ return object;
+}
+
+/*
+ * Inlined fastpath so that allocation functions (kmalloc, kmem_cache_alloc)
+ * have the fastpath folded into their functions. So no function call
+ * overhead for requests that can be satisfied on the fastpath.
+ *
+ * The fastpath works by first checking if the lockless freelist can be used.
+ * If not then __slab_alloc is called for slow processing.
+ *
+ * Otherwise we can simply pick the next object from the lockless free list.
+ */
+static void __always_inline *slab_alloc(struct kmem_cache *s,
+ gfp_t gfpflags, int node, void *addr)
+{
+ void **object;
+ unsigned long flags;
+ struct kmem_cache_cpu *c;
+
+ local_irq_save(flags);
+ c = get_cpu_slab(s, smp_processor_id());
+ if (unlikely(!c->freelist || !node_match(c, node)))
+
+ object = __slab_alloc(s, gfpflags, node, addr, c);
+
+ else {
+ object = c->freelist;
+ c->freelist = object[c->offset];
}
- init_object(s, object, 1);
- goto have_object;
+ local_irq_restore(flags);
+
+ if (unlikely((gfpflags & __GFP_ZERO) && object))
+ memset(object, 0, c->objsize);
+
+ return object;
}
void *kmem_cache_alloc(struct kmem_cache *s, gfp_t gfpflags)
#endif
/*
- * The fastpath only writes the cacheline of the page struct and the first
- * cacheline of the object.
+ * Slow patch handling. This may still be called frequently since objects
+ * have a longer lifetime than the cpu slabs in most processing loads.
*
- * We read the cpu_slab cacheline to check if the slab is the per cpu
- * slab for this processor.
+ * So we still attempt to reduce cache line usage. Just take the slab
+ * lock and free the item. If there is no additional partial page
+ * handling required then we can return immediately.
*/
-static void slab_free(struct kmem_cache *s, struct page *page,
- void *x, void *addr)
+static void __slab_free(struct kmem_cache *s, struct page *page,
+ void *x, void *addr, unsigned int offset)
{
void *prior;
void **object = (void *)x;
- unsigned long flags;
- local_irq_save(flags);
slab_lock(page);
- if (unlikely(PageError(page)))
+ if (unlikely(SlabDebug(page)))
goto debug;
checks_ok:
- prior = object[page->offset] = page->freelist;
+ prior = object[offset] = page->freelist;
page->freelist = object;
page->inuse--;
- if (unlikely(PageActive(page)))
- /*
- * Cpu slabs are never on partial lists and are
- * never freed.
- */
+ if (unlikely(SlabFrozen(page)))
goto out_unlock;
if (unlikely(!page->inuse))
* then add it.
*/
if (unlikely(!prior))
- add_partial(get_node(s, page_to_nid(page)), page);
+ add_partial_tail(get_node(s, page_to_nid(page)), page);
out_unlock:
slab_unlock(page);
- local_irq_restore(flags);
return;
slab_empty:
slab_unlock(page);
discard_slab(s, page);
- local_irq_restore(flags);
return;
debug:
- if (!free_object_checks(s, page, x))
+ if (!free_debug_processing(s, page, x, addr))
goto out_unlock;
- if (!PageActive(page) && !page->freelist)
- remove_full(s, page);
- if (s->flags & SLAB_STORE_USER)
- set_track(s, x, TRACK_FREE, addr);
- if (s->flags & SLAB_TRACE) {
- printk(KERN_INFO "TRACE %s free 0x%p inuse=%d fp=0x%p\n",
- s->name, object, page->inuse,
- page->freelist);
- print_section("Object", (void *)object, s->objsize);
- dump_stack();
- }
- init_object(s, object, 0);
goto checks_ok;
}
+/*
+ * Fastpath with forced inlining to produce a kfree and kmem_cache_free that
+ * can perform fastpath freeing without additional function calls.
+ *
+ * The fastpath is only possible if we are freeing to the current cpu slab
+ * of this processor. This typically the case if we have just allocated
+ * the item before.
+ *
+ * If fastpath is not possible then fall back to __slab_free where we deal
+ * with all sorts of special processing.
+ */
+static void __always_inline slab_free(struct kmem_cache *s,
+ struct page *page, void *x, void *addr)
+{
+ void **object = (void *)x;
+ unsigned long flags;
+ struct kmem_cache_cpu *c;
+
+ local_irq_save(flags);
+ debug_check_no_locks_freed(object, s->objsize);
+ c = get_cpu_slab(s, smp_processor_id());
+ if (likely(page == c->page && c->node >= 0)) {
+ object[c->offset] = c->freelist;
+ c->freelist = object;
+ } else
+ __slab_free(s, page, x, addr, c->offset);
+
+ local_irq_restore(flags);
+}
+
void kmem_cache_free(struct kmem_cache *s, void *x)
{
struct page *page;
static int slub_nomerge;
/*
- * Debug settings:
- */
-static int slub_debug;
-
-static char *slub_debug_slabs;
-
-/*
* Calculate the order of allocation given an slab object size.
*
* The order of allocation has significant impact on performance and other
* requested a higher mininum order then we start with that one instead of
* the smallest order which will fit the object.
*/
-static int calculate_order(int size)
+static inline int slab_order(int size, int min_objects,
+ int max_order, int fract_leftover)
{
int order;
int rem;
+ int min_order = slub_min_order;
- for (order = max(slub_min_order, fls(size - 1) - PAGE_SHIFT);
- order < MAX_ORDER; order++) {
- unsigned long slab_size = PAGE_SIZE << order;
+ for (order = max(min_order,
+ fls(min_objects * size - 1) - PAGE_SHIFT);
+ order <= max_order; order++) {
- if (slub_max_order > order &&
- slab_size < slub_min_objects * size)
- continue;
+ unsigned long slab_size = PAGE_SIZE << order;
- if (slab_size < size)
+ if (slab_size < min_objects * size)
continue;
rem = slab_size % size;
- if (rem <= slab_size / 8)
+ if (rem <= slab_size / fract_leftover)
break;
}
- if (order >= MAX_ORDER)
- return -E2BIG;
return order;
}
+static inline int calculate_order(int size)
+{
+ int order;
+ int min_objects;
+ int fraction;
+
+ /*
+ * Attempt to find best configuration for a slab. This
+ * works by first attempting to generate a layout with
+ * the best configuration and backing off gradually.
+ *
+ * First we reduce the acceptable waste in a slab. Then
+ * we reduce the minimum objects required in a slab.
+ */
+ min_objects = slub_min_objects;
+ while (min_objects > 1) {
+ fraction = 8;
+ while (fraction >= 4) {
+ order = slab_order(size, min_objects,
+ slub_max_order, fraction);
+ if (order <= slub_max_order)
+ return order;
+ fraction /= 2;
+ }
+ min_objects /= 2;
+ }
+
+ /*
+ * We were unable to place multiple objects in a slab. Now
+ * lets see if we can place a single object there.
+ */
+ order = slab_order(size, 1, slub_max_order, 1);
+ if (order <= slub_max_order)
+ return order;
+
+ /*
+ * Doh this slab cannot be placed using slub_max_order.
+ */
+ order = slab_order(size, 1, MAX_ORDER, 1);
+ if (order <= MAX_ORDER)
+ return order;
+ return -ENOSYS;
+}
+
/*
* Figure out what the alignment of the objects will be.
*/
return ALIGN(align, sizeof(void *));
}
+static void init_kmem_cache_cpu(struct kmem_cache *s,
+ struct kmem_cache_cpu *c)
+{
+ c->page = NULL;
+ c->freelist = NULL;
+ c->node = 0;
+ c->offset = s->offset / sizeof(void *);
+ c->objsize = s->objsize;
+}
+
static void init_kmem_cache_node(struct kmem_cache_node *n)
{
n->nr_partial = 0;
atomic_long_set(&n->nr_slabs, 0);
spin_lock_init(&n->list_lock);
INIT_LIST_HEAD(&n->partial);
+#ifdef CONFIG_SLUB_DEBUG
INIT_LIST_HEAD(&n->full);
+#endif
}
-#ifdef CONFIG_NUMA
+#ifdef CONFIG_SMP
/*
- * No kmalloc_node yet so do it by hand. We know that this is the first
- * slab on the node for this slabcache. There are no concurrent accesses
- * possible.
+ * Per cpu array for per cpu structures.
*
- * Note that this function only works on the kmalloc_node_cache
- * when allocating for the kmalloc_node_cache.
+ * The per cpu array places all kmem_cache_cpu structures from one processor
+ * close together meaning that it becomes possible that multiple per cpu
+ * structures are contained in one cacheline. This may be particularly
+ * beneficial for the kmalloc caches.
+ *
+ * A desktop system typically has around 60-80 slabs. With 100 here we are
+ * likely able to get per cpu structures for all caches from the array defined
+ * here. We must be able to cover all kmalloc caches during bootstrap.
+ *
+ * If the per cpu array is exhausted then fall back to kmalloc
+ * of individual cachelines. No sharing is possible then.
*/
-static struct kmem_cache_node * __init early_kmem_cache_node_alloc(gfp_t gfpflags,
- int node)
+#define NR_KMEM_CACHE_CPU 100
+
+static DEFINE_PER_CPU(struct kmem_cache_cpu,
+ kmem_cache_cpu)[NR_KMEM_CACHE_CPU];
+
+static DEFINE_PER_CPU(struct kmem_cache_cpu *, kmem_cache_cpu_free);
+static cpumask_t kmem_cach_cpu_free_init_once = CPU_MASK_NONE;
+
+static struct kmem_cache_cpu *alloc_kmem_cache_cpu(struct kmem_cache *s,
+ int cpu, gfp_t flags)
{
- struct page *page;
- struct kmem_cache_node *n;
+ struct kmem_cache_cpu *c = per_cpu(kmem_cache_cpu_free, cpu);
- BUG_ON(kmalloc_caches->size < sizeof(struct kmem_cache_node));
+ if (c)
+ per_cpu(kmem_cache_cpu_free, cpu) =
+ (void *)c->freelist;
+ else {
+ /* Table overflow: So allocate ourselves */
+ c = kmalloc_node(
+ ALIGN(sizeof(struct kmem_cache_cpu), cache_line_size()),
+ flags, cpu_to_node(cpu));
+ if (!c)
+ return NULL;
+ }
- page = new_slab(kmalloc_caches, gfpflags | GFP_THISNODE, node);
- /* new_slab() disables interupts */
- local_irq_enable();
+ init_kmem_cache_cpu(s, c);
+ return c;
+}
- BUG_ON(!page);
- n = page->freelist;
- BUG_ON(!n);
- page->freelist = get_freepointer(kmalloc_caches, n);
- page->inuse++;
- kmalloc_caches->node[node] = n;
- init_object(kmalloc_caches, n, 1);
- init_kmem_cache_node(n);
- atomic_long_inc(&n->nr_slabs);
- add_partial(n, page);
- return n;
+static void free_kmem_cache_cpu(struct kmem_cache_cpu *c, int cpu)
+{
+ if (c < per_cpu(kmem_cache_cpu, cpu) ||
+ c > per_cpu(kmem_cache_cpu, cpu) + NR_KMEM_CACHE_CPU) {
+ kfree(c);
+ return;
+ }
+ c->freelist = (void *)per_cpu(kmem_cache_cpu_free, cpu);
+ per_cpu(kmem_cache_cpu_free, cpu) = c;
}
-static void free_kmem_cache_nodes(struct kmem_cache *s)
+static void free_kmem_cache_cpus(struct kmem_cache *s)
{
- int node;
+ int cpu;
- for_each_online_node(node) {
- struct kmem_cache_node *n = s->node[node];
- if (n && n != &s->local_node)
- kmem_cache_free(kmalloc_caches, n);
- s->node[node] = NULL;
+ for_each_online_cpu(cpu) {
+ struct kmem_cache_cpu *c = get_cpu_slab(s, cpu);
+
+ if (c) {
+ s->cpu_slab[cpu] = NULL;
+ free_kmem_cache_cpu(c, cpu);
+ }
}
}
-static int init_kmem_cache_nodes(struct kmem_cache *s, gfp_t gfpflags)
+static int alloc_kmem_cache_cpus(struct kmem_cache *s, gfp_t flags)
{
- int node;
- int local_node;
+ int cpu;
- if (slab_state >= UP)
- local_node = page_to_nid(virt_to_page(s));
- else
- local_node = 0;
+ for_each_online_cpu(cpu) {
+ struct kmem_cache_cpu *c = get_cpu_slab(s, cpu);
- for_each_online_node(node) {
- struct kmem_cache_node *n;
+ if (c)
+ continue;
- if (local_node == node)
- n = &s->local_node;
- else {
- if (slab_state == DOWN) {
+ c = alloc_kmem_cache_cpu(s, cpu, flags);
+ if (!c) {
+ free_kmem_cache_cpus(s);
+ return 0;
+ }
+ s->cpu_slab[cpu] = c;
+ }
+ return 1;
+}
+
+/*
+ * Initialize the per cpu array.
+ */
+static void init_alloc_cpu_cpu(int cpu)
+{
+ int i;
+
+ if (cpu_isset(cpu, kmem_cach_cpu_free_init_once))
+ return;
+
+ for (i = NR_KMEM_CACHE_CPU - 1; i >= 0; i--)
+ free_kmem_cache_cpu(&per_cpu(kmem_cache_cpu, cpu)[i], cpu);
+
+ cpu_set(cpu, kmem_cach_cpu_free_init_once);
+}
+
+static void __init init_alloc_cpu(void)
+{
+ int cpu;
+
+ for_each_online_cpu(cpu)
+ init_alloc_cpu_cpu(cpu);
+ }
+
+#else
+static inline void free_kmem_cache_cpus(struct kmem_cache *s) {}
+static inline void init_alloc_cpu(void) {}
+
+static inline int alloc_kmem_cache_cpus(struct kmem_cache *s, gfp_t flags)
+{
+ init_kmem_cache_cpu(s, &s->cpu_slab);
+ return 1;
+}
+#endif
+
+#ifdef CONFIG_NUMA
+/*
+ * No kmalloc_node yet so do it by hand. We know that this is the first
+ * slab on the node for this slabcache. There are no concurrent accesses
+ * possible.
+ *
+ * Note that this function only works on the kmalloc_node_cache
+ * when allocating for the kmalloc_node_cache. This is used for bootstrapping
+ * memory on a fresh node that has no slab structures yet.
+ */
+static struct kmem_cache_node *early_kmem_cache_node_alloc(gfp_t gfpflags,
+ int node)
+{
+ struct page *page;
+ struct kmem_cache_node *n;
+
+ BUG_ON(kmalloc_caches->size < sizeof(struct kmem_cache_node));
+
+ page = new_slab(kmalloc_caches, gfpflags, node);
+
+ BUG_ON(!page);
+ if (page_to_nid(page) != node) {
+ printk(KERN_ERR "SLUB: Unable to allocate memory from "
+ "node %d\n", node);
+ printk(KERN_ERR "SLUB: Allocating a useless per node structure "
+ "in order to be able to continue\n");
+ }
+
+ n = page->freelist;
+ BUG_ON(!n);
+ page->freelist = get_freepointer(kmalloc_caches, n);
+ page->inuse++;
+ kmalloc_caches->node[node] = n;
+#ifdef CONFIG_SLUB_DEBUG
+ init_object(kmalloc_caches, n, 1);
+ init_tracking(kmalloc_caches, n);
+#endif
+ init_kmem_cache_node(n);
+ atomic_long_inc(&n->nr_slabs);
+ add_partial(n, page);
+ return n;
+}
+
+static void free_kmem_cache_nodes(struct kmem_cache *s)
+{
+ int node;
+
+ for_each_node_state(node, N_NORMAL_MEMORY) {
+ struct kmem_cache_node *n = s->node[node];
+ if (n && n != &s->local_node)
+ kmem_cache_free(kmalloc_caches, n);
+ s->node[node] = NULL;
+ }
+}
+
+static int init_kmem_cache_nodes(struct kmem_cache *s, gfp_t gfpflags)
+{
+ int node;
+ int local_node;
+
+ if (slab_state >= UP)
+ local_node = page_to_nid(virt_to_page(s));
+ else
+ local_node = 0;
+
+ for_each_node_state(node, N_NORMAL_MEMORY) {
+ struct kmem_cache_node *n;
+
+ if (local_node == node)
+ n = &s->local_node;
+ else {
+ if (slab_state == DOWN) {
n = early_kmem_cache_node_alloc(gfpflags,
node);
continue;
* then we should never poison the object itself.
*/
if ((flags & SLAB_POISON) && !(flags & SLAB_DESTROY_BY_RCU) &&
- !s->ctor && !s->dtor)
+ !s->ctor)
s->flags |= __OBJECT_POISON;
else
s->flags &= ~__OBJECT_POISON;
*/
size = ALIGN(size, sizeof(void *));
+#ifdef CONFIG_SLUB_DEBUG
/*
* If we are Redzoning then check if there is some space between the
* end of the object and the free pointer. If not then add an
*/
if ((flags & SLAB_RED_ZONE) && size == s->objsize)
size += sizeof(void *);
+#endif
/*
* With that we have determined the number of bytes in actual use
s->inuse = size;
if (((flags & (SLAB_DESTROY_BY_RCU | SLAB_POISON)) ||
- s->ctor || s->dtor)) {
+ s->ctor)) {
/*
* Relocate free pointer after the object if it is not
* permitted to overwrite the first word of the object on
size += sizeof(void *);
}
+#ifdef CONFIG_SLUB_DEBUG
if (flags & SLAB_STORE_USER)
/*
* Need to store information about allocs and frees after
* of the object.
*/
size += sizeof(void *);
+#endif
/*
* Determine the alignment based on various parameters that the
*/
s->objects = (PAGE_SIZE << s->order) / size;
- /*
- * Verify that the number of objects is within permitted limits.
- * The page->inuse field is only 16 bit wide! So we cannot have
- * more than 64k objects per slab.
- */
- if (!s->objects || s->objects > 65535)
- return 0;
- return 1;
+ return !!s->objects;
}
static int kmem_cache_open(struct kmem_cache *s, gfp_t gfpflags,
const char *name, size_t size,
size_t align, unsigned long flags,
- void (*ctor)(void *, struct kmem_cache *, unsigned long),
- void (*dtor)(void *, struct kmem_cache *, unsigned long))
+ void (*ctor)(struct kmem_cache *, void *))
{
memset(s, 0, kmem_size);
s->name = name;
s->ctor = ctor;
- s->dtor = dtor;
s->objsize = size;
- s->flags = flags;
s->align = align;
-
- /*
- * The page->offset field is only 16 bit wide. This is an offset
- * in units of words from the beginning of an object. If the slab
- * size is bigger then we cannot move the free pointer behind the
- * object anymore.
- *
- * On 32 bit platforms the limit is 256k. On 64bit platforms
- * the limit is 512k.
- *
- * Debugging or ctor/dtors may create a need to move the free
- * pointer. Fail if this happens.
- */
- if (s->size >= 65535 * sizeof(void *)) {
- BUG_ON(flags & (SLAB_RED_ZONE | SLAB_POISON |
- SLAB_STORE_USER | SLAB_DESTROY_BY_RCU));
- BUG_ON(ctor || dtor);
- }
- else
- /*
- * Enable debugging if selected on the kernel commandline.
- */
- if (slub_debug && (!slub_debug_slabs ||
- strncmp(slub_debug_slabs, name,
- strlen(slub_debug_slabs)) == 0))
- s->flags |= slub_debug;
+ s->flags = kmem_cache_flags(size, flags, name, ctor);
if (!calculate_sizes(s))
goto error;
#ifdef CONFIG_NUMA
s->defrag_ratio = 100;
#endif
+ if (!init_kmem_cache_nodes(s, gfpflags & ~SLUB_DMA))
+ goto error;
- if (init_kmem_cache_nodes(s, gfpflags & ~SLUB_DMA))
+ if (alloc_kmem_cache_cpus(s, gfpflags & ~SLUB_DMA))
return 1;
+ free_kmem_cache_nodes(s);
error:
if (flags & SLAB_PANIC)
panic("Cannot create slab %s size=%lu realsize=%u "
s->offset, flags);
return 0;
}
-EXPORT_SYMBOL(kmem_cache_open);
/*
* Check if a given pointer is valid
/*
* Release all resources used by a slab cache.
*/
-static int kmem_cache_close(struct kmem_cache *s)
+static inline int kmem_cache_close(struct kmem_cache *s)
{
int node;
flush_all(s);
/* Attempt to free all objects */
- for_each_online_node(node) {
+ free_kmem_cache_cpus(s);
+ for_each_node_state(node, N_NORMAL_MEMORY) {
struct kmem_cache_node *n = get_node(s, node);
n->nr_partial -= free_list(s, n, &n->partial);
s->refcount--;
if (!s->refcount) {
list_del(&s->list);
+ up_write(&slub_lock);
if (kmem_cache_close(s))
WARN_ON(1);
sysfs_slab_remove(s);
kfree(s);
- }
- up_write(&slub_lock);
+ } else
+ up_write(&slub_lock);
}
EXPORT_SYMBOL(kmem_cache_destroy);
* Kmalloc subsystem
*******************************************************************/
-struct kmem_cache kmalloc_caches[KMALLOC_SHIFT_HIGH + 1] __cacheline_aligned;
+struct kmem_cache kmalloc_caches[PAGE_SHIFT] __cacheline_aligned;
EXPORT_SYMBOL(kmalloc_caches);
#ifdef CONFIG_ZONE_DMA
-static struct kmem_cache *kmalloc_caches_dma[KMALLOC_SHIFT_HIGH + 1];
+static struct kmem_cache *kmalloc_caches_dma[PAGE_SHIFT];
#endif
static int __init setup_slub_min_order(char *str)
__setup("slub_nomerge", setup_slub_nomerge);
-static int __init setup_slub_debug(char *str)
-{
- if (!str || *str != '=')
- slub_debug = DEBUG_DEFAULT_FLAGS;
- else {
- str++;
- if (*str == 0 || *str == ',')
- slub_debug = DEBUG_DEFAULT_FLAGS;
- else
- for( ;*str && *str != ','; str++)
- switch (*str) {
- case 'f' : case 'F' :
- slub_debug |= SLAB_DEBUG_FREE;
- break;
- case 'z' : case 'Z' :
- slub_debug |= SLAB_RED_ZONE;
- break;
- case 'p' : case 'P' :
- slub_debug |= SLAB_POISON;
- break;
- case 'u' : case 'U' :
- slub_debug |= SLAB_STORE_USER;
- break;
- case 't' : case 'T' :
- slub_debug |= SLAB_TRACE;
- break;
- default:
- printk(KERN_ERR "slub_debug option '%c' "
- "unknown. skipped\n",*str);
- }
- }
-
- if (*str == ',')
- slub_debug_slabs = str + 1;
- return 1;
-}
-
-__setup("slub_debug", setup_slub_debug);
-
static struct kmem_cache *create_kmalloc_cache(struct kmem_cache *s,
const char *name, int size, gfp_t gfp_flags)
{
down_write(&slub_lock);
if (!kmem_cache_open(s, gfp_flags, name, size, ARCH_KMALLOC_MINALIGN,
- flags, NULL, NULL))
+ flags, NULL))
goto panic;
list_add(&s->list, &slab_caches);
panic("Creation of kmalloc slab %s size=%d failed.\n", name, size);
}
-static struct kmem_cache *get_slab(size_t size, gfp_t flags)
+#ifdef CONFIG_ZONE_DMA
+
+static void sysfs_add_func(struct work_struct *w)
{
- int index = kmalloc_index(size);
+ struct kmem_cache *s;
- if (!index)
- return NULL;
+ down_write(&slub_lock);
+ list_for_each_entry(s, &slab_caches, list) {
+ if (s->flags & __SYSFS_ADD_DEFERRED) {
+ s->flags &= ~__SYSFS_ADD_DEFERRED;
+ sysfs_slab_add(s);
+ }
+ }
+ up_write(&slub_lock);
+}
- /* Allocation too large? */
- BUG_ON(index < 0);
+static DECLARE_WORK(sysfs_add_work, sysfs_add_func);
-#ifdef CONFIG_ZONE_DMA
- if ((flags & SLUB_DMA)) {
- struct kmem_cache *s;
- struct kmem_cache *x;
- char *text;
- size_t realsize;
-
- s = kmalloc_caches_dma[index];
- if (s)
- return s;
+static noinline struct kmem_cache *dma_kmalloc_cache(int index, gfp_t flags)
+{
+ struct kmem_cache *s;
+ char *text;
+ size_t realsize;
- /* Dynamically create dma cache */
- x = kmalloc(kmem_size, flags & ~SLUB_DMA);
- if (!x)
- panic("Unable to allocate memory for dma cache\n");
+ s = kmalloc_caches_dma[index];
+ if (s)
+ return s;
- if (index <= KMALLOC_SHIFT_HIGH)
- realsize = 1 << index;
- else {
- if (index == 1)
- realsize = 96;
- else
- realsize = 192;
- }
+ /* Dynamically create dma cache */
+ if (flags & __GFP_WAIT)
+ down_write(&slub_lock);
+ else {
+ if (!down_write_trylock(&slub_lock))
+ goto out;
+ }
- text = kasprintf(flags & ~SLUB_DMA, "kmalloc_dma-%d",
- (unsigned int)realsize);
- s = create_kmalloc_cache(x, text, realsize, flags);
- kmalloc_caches_dma[index] = s;
- return s;
+ if (kmalloc_caches_dma[index])
+ goto unlock_out;
+
+ realsize = kmalloc_caches[index].objsize;
+ text = kasprintf(flags & ~SLUB_DMA, "kmalloc_dma-%d", (unsigned int)realsize),
+ s = kmalloc(kmem_size, flags & ~SLUB_DMA);
+
+ if (!s || !text || !kmem_cache_open(s, flags, text,
+ realsize, ARCH_KMALLOC_MINALIGN,
+ SLAB_CACHE_DMA|__SYSFS_ADD_DEFERRED, NULL)) {
+ kfree(s);
+ kfree(text);
+ goto unlock_out;
}
+
+ list_add(&s->list, &slab_caches);
+ kmalloc_caches_dma[index] = s;
+
+ schedule_work(&sysfs_add_work);
+
+unlock_out:
+ up_write(&slub_lock);
+out:
+ return kmalloc_caches_dma[index];
+}
+#endif
+
+/*
+ * Conversion table for small slabs sizes / 8 to the index in the
+ * kmalloc array. This is necessary for slabs < 192 since we have non power
+ * of two cache sizes there. The size of larger slabs can be determined using
+ * fls.
+ */
+static s8 size_index[24] = {
+ 3, /* 8 */
+ 4, /* 16 */
+ 5, /* 24 */
+ 5, /* 32 */
+ 6, /* 40 */
+ 6, /* 48 */
+ 6, /* 56 */
+ 6, /* 64 */
+ 1, /* 72 */
+ 1, /* 80 */
+ 1, /* 88 */
+ 1, /* 96 */
+ 7, /* 104 */
+ 7, /* 112 */
+ 7, /* 120 */
+ 7, /* 128 */
+ 2, /* 136 */
+ 2, /* 144 */
+ 2, /* 152 */
+ 2, /* 160 */
+ 2, /* 168 */
+ 2, /* 176 */
+ 2, /* 184 */
+ 2 /* 192 */
+};
+
+static struct kmem_cache *get_slab(size_t size, gfp_t flags)
+{
+ int index;
+
+ if (size <= 192) {
+ if (!size)
+ return ZERO_SIZE_PTR;
+
+ index = size_index[(size - 1) / 8];
+ } else
+ index = fls(size - 1);
+
+#ifdef CONFIG_ZONE_DMA
+ if (unlikely((flags & SLUB_DMA)))
+ return dma_kmalloc_cache(index, flags);
+
#endif
return &kmalloc_caches[index];
}
void *__kmalloc(size_t size, gfp_t flags)
{
- struct kmem_cache *s = get_slab(size, flags);
+ struct kmem_cache *s;
- if (s)
- return slab_alloc(s, flags, -1, __builtin_return_address(0));
- return NULL;
+ if (unlikely(size > PAGE_SIZE / 2))
+ return (void *)__get_free_pages(flags | __GFP_COMP,
+ get_order(size));
+
+ s = get_slab(size, flags);
+
+ if (unlikely(ZERO_OR_NULL_PTR(s)))
+ return s;
+
+ return slab_alloc(s, flags, -1, __builtin_return_address(0));
}
EXPORT_SYMBOL(__kmalloc);
#ifdef CONFIG_NUMA
void *__kmalloc_node(size_t size, gfp_t flags, int node)
{
- struct kmem_cache *s = get_slab(size, flags);
+ struct kmem_cache *s;
- if (s)
- return slab_alloc(s, flags, node, __builtin_return_address(0));
- return NULL;
+ if (unlikely(size > PAGE_SIZE / 2))
+ return (void *)__get_free_pages(flags | __GFP_COMP,
+ get_order(size));
+
+ s = get_slab(size, flags);
+
+ if (unlikely(ZERO_OR_NULL_PTR(s)))
+ return s;
+
+ return slab_alloc(s, flags, node, __builtin_return_address(0));
}
EXPORT_SYMBOL(__kmalloc_node);
#endif
size_t ksize(const void *object)
{
- struct page *page = get_object_page(object);
+ struct page *page;
struct kmem_cache *s;
+ BUG_ON(!object);
+ if (unlikely(object == ZERO_SIZE_PTR))
+ return 0;
+
+ page = virt_to_head_page(object);
BUG_ON(!page);
+
+ if (unlikely(!PageSlab(page)))
+ return PAGE_SIZE << compound_order(page);
+
s = page->slab;
BUG_ON(!s);
void kfree(const void *x)
{
- struct kmem_cache *s;
struct page *page;
- if (!x)
+ if (unlikely(ZERO_OR_NULL_PTR(x)))
return;
page = virt_to_head_page(x);
- s = page->slab;
-
- slab_free(s, page, (void *)x, __builtin_return_address(0));
+ if (unlikely(!PageSlab(page))) {
+ put_page(page);
+ return;
+ }
+ slab_free(page->slab, page, (void *)x, __builtin_return_address(0));
}
EXPORT_SYMBOL(kfree);
return -ENOMEM;
flush_all(s);
- for_each_online_node(node) {
+ for_each_node_state(node, N_NORMAL_MEMORY) {
n = get_node(s, node);
if (!n->nr_partial)
slab_unlock(page);
discard_slab(s, page);
} else {
- if (n->nr_partial > MAX_PARTIAL)
- list_move(&page->lru,
- slabs_by_inuse + page->inuse);
+ list_move(&page->lru,
+ slabs_by_inuse + page->inuse);
}
}
- if (n->nr_partial <= MAX_PARTIAL)
- goto out;
-
/*
* Rebuild the partial list with the slabs filled up most
* first and the least used slabs at the end.
for (i = s->objects - 1; i >= 0; i--)
list_splice(slabs_by_inuse + i, n->partial.prev);
- out:
spin_unlock_irqrestore(&n->list_lock, flags);
}
}
EXPORT_SYMBOL(kmem_cache_shrink);
-/**
- * krealloc - reallocate memory. The contents will remain unchanged.
- *
- * @p: object to reallocate memory for.
- * @new_size: how many bytes of memory are required.
- * @flags: the type of memory to allocate.
- *
- * The contents of the object pointed to are preserved up to the
- * lesser of the new and old sizes. If @p is %NULL, krealloc()
- * behaves exactly like kmalloc(). If @size is 0 and @p is not a
- * %NULL pointer, the object pointed to is freed.
- */
-void *krealloc(const void *p, size_t new_size, gfp_t flags)
+#if defined(CONFIG_NUMA) && defined(CONFIG_MEMORY_HOTPLUG)
+static int slab_mem_going_offline_callback(void *arg)
{
- void *ret;
- size_t ks;
+ struct kmem_cache *s;
- if (unlikely(!p))
- return kmalloc(new_size, flags);
+ down_read(&slub_lock);
+ list_for_each_entry(s, &slab_caches, list)
+ kmem_cache_shrink(s);
+ up_read(&slub_lock);
- if (unlikely(!new_size)) {
- kfree(p);
- return NULL;
+ return 0;
+}
+
+static void slab_mem_offline_callback(void *arg)
+{
+ struct kmem_cache_node *n;
+ struct kmem_cache *s;
+ struct memory_notify *marg = arg;
+ int offline_node;
+
+ offline_node = marg->status_change_nid;
+
+ /*
+ * If the node still has available memory. we need kmem_cache_node
+ * for it yet.
+ */
+ if (offline_node < 0)
+ return;
+
+ down_read(&slub_lock);
+ list_for_each_entry(s, &slab_caches, list) {
+ n = get_node(s, offline_node);
+ if (n) {
+ /*
+ * if n->nr_slabs > 0, slabs still exist on the node
+ * that is going down. We were unable to free them,
+ * and offline_pages() function shoudn't call this
+ * callback. So, we must fail.
+ */
+ BUG_ON(atomic_long_read(&n->nr_slabs));
+
+ s->node[offline_node] = NULL;
+ kmem_cache_free(kmalloc_caches, n);
+ }
+ }
+ up_read(&slub_lock);
+}
+
+static int slab_mem_going_online_callback(void *arg)
+{
+ struct kmem_cache_node *n;
+ struct kmem_cache *s;
+ struct memory_notify *marg = arg;
+ int nid = marg->status_change_nid;
+ int ret = 0;
+
+ /*
+ * If the node's memory is already available, then kmem_cache_node is
+ * already created. Nothing to do.
+ */
+ if (nid < 0)
+ return 0;
+
+ /*
+ * We are bringing a node online. No memory is availabe yet. We must
+ * allocate a kmem_cache_node structure in order to bring the node
+ * online.
+ */
+ down_read(&slub_lock);
+ list_for_each_entry(s, &slab_caches, list) {
+ /*
+ * XXX: kmem_cache_alloc_node will fallback to other nodes
+ * since memory is not yet available from the node that
+ * is brought up.
+ */
+ n = kmem_cache_alloc(kmalloc_caches, GFP_KERNEL);
+ if (!n) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ init_kmem_cache_node(n);
+ s->node[nid] = n;
}
+out:
+ up_read(&slub_lock);
+ return ret;
+}
- ks = ksize(p);
- if (ks >= new_size)
- return (void *)p;
+static int slab_memory_callback(struct notifier_block *self,
+ unsigned long action, void *arg)
+{
+ int ret = 0;
- ret = kmalloc(new_size, flags);
- if (ret) {
- memcpy(ret, p, min(new_size, ks));
- kfree(p);
+ switch (action) {
+ case MEM_GOING_ONLINE:
+ ret = slab_mem_going_online_callback(arg);
+ break;
+ case MEM_GOING_OFFLINE:
+ ret = slab_mem_going_offline_callback(arg);
+ break;
+ case MEM_OFFLINE:
+ case MEM_CANCEL_ONLINE:
+ slab_mem_offline_callback(arg);
+ break;
+ case MEM_ONLINE:
+ case MEM_CANCEL_OFFLINE:
+ break;
}
+
+ ret = notifier_from_errno(ret);
return ret;
}
-EXPORT_SYMBOL(krealloc);
+
+#endif /* CONFIG_MEMORY_HOTPLUG */
/********************************************************************
* Basic setup of slabs
void __init kmem_cache_init(void)
{
int i;
+ int caches = 0;
+
+ init_alloc_cpu();
#ifdef CONFIG_NUMA
/*
*/
create_kmalloc_cache(&kmalloc_caches[0], "kmem_cache_node",
sizeof(struct kmem_cache_node), GFP_KERNEL);
+ kmalloc_caches[0].refcount = -1;
+ caches++;
+
+ hotplug_memory_notifier(slab_memory_callback, 1);
#endif
/* Able to allocate the per node structures */
slab_state = PARTIAL;
/* Caches that are not of the two-to-the-power-of size */
- create_kmalloc_cache(&kmalloc_caches[1],
+ if (KMALLOC_MIN_SIZE <= 64) {
+ create_kmalloc_cache(&kmalloc_caches[1],
"kmalloc-96", 96, GFP_KERNEL);
- create_kmalloc_cache(&kmalloc_caches[2],
+ caches++;
+ }
+ if (KMALLOC_MIN_SIZE <= 128) {
+ create_kmalloc_cache(&kmalloc_caches[2],
"kmalloc-192", 192, GFP_KERNEL);
+ caches++;
+ }
- for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++)
+ for (i = KMALLOC_SHIFT_LOW; i < PAGE_SHIFT; i++) {
create_kmalloc_cache(&kmalloc_caches[i],
"kmalloc", 1 << i, GFP_KERNEL);
+ caches++;
+ }
+
+
+ /*
+ * Patch up the size_index table if we have strange large alignment
+ * requirements for the kmalloc array. This is only the case for
+ * mips it seems. The standard arches will not generate any code here.
+ *
+ * Largest permitted alignment is 256 bytes due to the way we
+ * handle the index determination for the smaller caches.
+ *
+ * Make sure that nothing crazy happens if someone starts tinkering
+ * around with ARCH_KMALLOC_MINALIGN
+ */
+ BUILD_BUG_ON(KMALLOC_MIN_SIZE > 256 ||
+ (KMALLOC_MIN_SIZE & (KMALLOC_MIN_SIZE - 1)));
+
+ for (i = 8; i < KMALLOC_MIN_SIZE; i += 8)
+ size_index[(i - 1) / 8] = KMALLOC_SHIFT_LOW;
slab_state = UP;
/* Provide the correct kmalloc names now that the caches are up */
- for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++)
+ for (i = KMALLOC_SHIFT_LOW; i < PAGE_SHIFT; i++)
kmalloc_caches[i]. name =
kasprintf(GFP_KERNEL, "kmalloc-%d", 1 << i);
#ifdef CONFIG_SMP
register_cpu_notifier(&slab_notifier);
+ kmem_size = offsetof(struct kmem_cache, cpu_slab) +
+ nr_cpu_ids * sizeof(struct kmem_cache_cpu *);
+#else
+ kmem_size = sizeof(struct kmem_cache);
#endif
- if (nr_cpu_ids) /* Remove when nr_cpu_ids is fixed upstream ! */
- kmem_size = offsetof(struct kmem_cache, cpu_slab)
- + nr_cpu_ids * sizeof(struct page *);
printk(KERN_INFO "SLUB: Genslabs=%d, HWalign=%d, Order=%d-%d, MinObjects=%d,"
- " Processors=%d, Nodes=%d\n",
- KMALLOC_SHIFT_HIGH, cache_line_size(),
+ " CPUs=%d, Nodes=%d\n",
+ caches, cache_line_size(),
slub_min_order, slub_max_order, slub_min_objects,
nr_cpu_ids, nr_node_ids);
}
if (slub_nomerge || (s->flags & SLUB_NEVER_MERGE))
return 1;
- if (s->ctor || s->dtor)
+ if (s->ctor)
+ return 1;
+
+ /*
+ * We may have set a slab to be unmergeable during bootstrap.
+ */
+ if (s->refcount < 0)
return 1;
return 0;
}
static struct kmem_cache *find_mergeable(size_t size,
- size_t align, unsigned long flags,
- void (*ctor)(void *, struct kmem_cache *, unsigned long),
- void (*dtor)(void *, struct kmem_cache *, unsigned long))
+ size_t align, unsigned long flags, const char *name,
+ void (*ctor)(struct kmem_cache *, void *))
{
- struct list_head *h;
+ struct kmem_cache *s;
if (slub_nomerge || (flags & SLUB_NEVER_MERGE))
return NULL;
- if (ctor || dtor)
+ if (ctor)
return NULL;
size = ALIGN(size, sizeof(void *));
align = calculate_alignment(flags, align, size);
size = ALIGN(size, align);
+ flags = kmem_cache_flags(size, flags, name, NULL);
- list_for_each(h, &slab_caches) {
- struct kmem_cache *s =
- container_of(h, struct kmem_cache, list);
-
+ list_for_each_entry(s, &slab_caches, list) {
if (slab_unmergeable(s))
continue;
if (size > s->size)
continue;
- if (((flags | slub_debug) & SLUB_MERGE_SAME) !=
- (s->flags & SLUB_MERGE_SAME))
+ if ((flags & SLUB_MERGE_SAME) != (s->flags & SLUB_MERGE_SAME))
continue;
/*
* Check if alignment is compatible.
struct kmem_cache *kmem_cache_create(const char *name, size_t size,
size_t align, unsigned long flags,
- void (*ctor)(void *, struct kmem_cache *, unsigned long),
- void (*dtor)(void *, struct kmem_cache *, unsigned long))
+ void (*ctor)(struct kmem_cache *, void *))
{
struct kmem_cache *s;
down_write(&slub_lock);
- s = find_mergeable(size, align, flags, dtor, ctor);
+ s = find_mergeable(size, align, flags, name, ctor);
if (s) {
+ int cpu;
+
s->refcount++;
/*
* Adjust the object sizes so that we clear
* the complete object on kzalloc.
*/
s->objsize = max(s->objsize, (int)size);
+
+ /*
+ * And then we need to update the object size in the
+ * per cpu structures
+ */
+ for_each_online_cpu(cpu)
+ get_cpu_slab(s, cpu)->objsize = s->objsize;
s->inuse = max_t(int, s->inuse, ALIGN(size, sizeof(void *)));
+ up_write(&slub_lock);
if (sysfs_slab_alias(s, name))
goto err;
- } else {
- s = kmalloc(kmem_size, GFP_KERNEL);
- if (s && kmem_cache_open(s, GFP_KERNEL, name,
- size, align, flags, ctor, dtor)) {
- if (sysfs_slab_add(s)) {
- kfree(s);
- goto err;
- }
+ return s;
+ }
+ s = kmalloc(kmem_size, GFP_KERNEL);
+ if (s) {
+ if (kmem_cache_open(s, GFP_KERNEL, name,
+ size, align, flags, ctor)) {
list_add(&s->list, &slab_caches);
- } else
- kfree(s);
+ up_write(&slub_lock);
+ if (sysfs_slab_add(s))
+ goto err;
+ return s;
+ }
+ kfree(s);
}
up_write(&slub_lock);
- return s;
err:
- up_write(&slub_lock);
if (flags & SLAB_PANIC)
panic("Cannot create slabcache %s\n", name);
else
s = NULL;
- return s;
-}
-EXPORT_SYMBOL(kmem_cache_create);
-
-void *kmem_cache_zalloc(struct kmem_cache *s, gfp_t flags)
-{
- void *x;
-
- x = slab_alloc(s, flags, -1, __builtin_return_address(0));
- if (x)
- memset(x, 0, s->objsize);
- return x;
-}
-EXPORT_SYMBOL(kmem_cache_zalloc);
-
-#ifdef CONFIG_SMP
-static void for_all_slabs(void (*func)(struct kmem_cache *, int), int cpu)
-{
- struct list_head *h;
-
- down_read(&slub_lock);
- list_for_each(h, &slab_caches) {
- struct kmem_cache *s =
- container_of(h, struct kmem_cache, list);
-
- func(s, cpu);
- }
- up_read(&slub_lock);
-}
-
-/*
- * Use the cpu notifier to insure that the cpu slabs are flushed when
- * necessary.
- */
-static int __cpuinit slab_cpuup_callback(struct notifier_block *nfb,
- unsigned long action, void *hcpu)
-{
- long cpu = (long)hcpu;
-
- switch (action) {
- case CPU_UP_CANCELED:
- case CPU_DEAD:
- for_all_slabs(__flush_cpu_slab, cpu);
- break;
- default:
- break;
- }
- return NOTIFY_OK;
-}
-
-static struct notifier_block __cpuinitdata slab_notifier =
- { &slab_cpuup_callback, NULL, 0 };
-
-#endif
-
-#ifdef CONFIG_NUMA
-
-/*****************************************************************
- * Generic reaper used to support the page allocator
- * (the cpu slabs are reaped by a per slab workqueue).
- *
- * Maybe move this to the page allocator?
- ****************************************************************/
-
-static DEFINE_PER_CPU(unsigned long, reap_node);
-
-static void init_reap_node(int cpu)
-{
- int node;
-
- node = next_node(cpu_to_node(cpu), node_online_map);
- if (node == MAX_NUMNODES)
- node = first_node(node_online_map);
-
- __get_cpu_var(reap_node) = node;
-}
-
-static void next_reap_node(void)
-{
- int node = __get_cpu_var(reap_node);
-
- /*
- * Also drain per cpu pages on remote zones
- */
- if (node != numa_node_id())
- drain_node_pages(node);
-
- node = next_node(node, node_online_map);
- if (unlikely(node >= MAX_NUMNODES))
- node = first_node(node_online_map);
- __get_cpu_var(reap_node) = node;
-}
-#else
-#define init_reap_node(cpu) do { } while (0)
-#define next_reap_node(void) do { } while (0)
-#endif
-
-#define REAPTIMEOUT_CPUC (2*HZ)
-
-#ifdef CONFIG_SMP
-static DEFINE_PER_CPU(struct delayed_work, reap_work);
-
-static void cache_reap(struct work_struct *unused)
-{
- next_reap_node();
- refresh_cpu_vm_stats(smp_processor_id());
- schedule_delayed_work(&__get_cpu_var(reap_work),
- REAPTIMEOUT_CPUC);
-}
-
-static void __devinit start_cpu_timer(int cpu)
-{
- struct delayed_work *reap_work = &per_cpu(reap_work, cpu);
-
- /*
- * When this gets called from do_initcalls via cpucache_init(),
- * init_workqueues() has already run, so keventd will be setup
- * at that time.
- */
- if (keventd_up() && reap_work->work.func == NULL) {
- init_reap_node(cpu);
- INIT_DELAYED_WORK(reap_work, cache_reap);
- schedule_delayed_work_on(cpu, reap_work, HZ + 3 * cpu);
- }
-}
-
-static int __init cpucache_init(void)
-{
- int cpu;
-
- /*
- * Register the timers that drain pcp pages and update vm statistics
- */
- for_each_online_cpu(cpu)
- start_cpu_timer(cpu);
- return 0;
+ return s;
}
-__initcall(cpucache_init);
-#endif
-
-#ifdef SLUB_RESILIENCY_TEST
-static unsigned long validate_slab_cache(struct kmem_cache *s);
+EXPORT_SYMBOL(kmem_cache_create);
-static void resiliency_test(void)
+#ifdef CONFIG_SMP
+/*
+ * Use the cpu notifier to insure that the cpu slabs are flushed when
+ * necessary.
+ */
+static int __cpuinit slab_cpuup_callback(struct notifier_block *nfb,
+ unsigned long action, void *hcpu)
{
- u8 *p;
-
- printk(KERN_ERR "SLUB resiliency testing\n");
- printk(KERN_ERR "-----------------------\n");
- printk(KERN_ERR "A. Corruption after allocation\n");
-
- p = kzalloc(16, GFP_KERNEL);
- p[16] = 0x12;
- printk(KERN_ERR "\n1. kmalloc-16: Clobber Redzone/next pointer"
- " 0x12->0x%p\n\n", p + 16);
-
- validate_slab_cache(kmalloc_caches + 4);
-
- /* Hmmm... The next two are dangerous */
- p = kzalloc(32, GFP_KERNEL);
- p[32 + sizeof(void *)] = 0x34;
- printk(KERN_ERR "\n2. kmalloc-32: Clobber next pointer/next slab"
- " 0x34 -> -0x%p\n", p);
- printk(KERN_ERR "If allocated object is overwritten then not detectable\n\n");
+ long cpu = (long)hcpu;
+ struct kmem_cache *s;
+ unsigned long flags;
- validate_slab_cache(kmalloc_caches + 5);
- p = kzalloc(64, GFP_KERNEL);
- p += 64 + (get_cycles() & 0xff) * sizeof(void *);
- *p = 0x56;
- printk(KERN_ERR "\n3. kmalloc-64: corrupting random byte 0x56->0x%p\n",
- p);
- printk(KERN_ERR "If allocated object is overwritten then not detectable\n\n");
- validate_slab_cache(kmalloc_caches + 6);
+ switch (action) {
+ case CPU_UP_PREPARE:
+ case CPU_UP_PREPARE_FROZEN:
+ init_alloc_cpu_cpu(cpu);
+ down_read(&slub_lock);
+ list_for_each_entry(s, &slab_caches, list)
+ s->cpu_slab[cpu] = alloc_kmem_cache_cpu(s, cpu,
+ GFP_KERNEL);
+ up_read(&slub_lock);
+ break;
- printk(KERN_ERR "\nB. Corruption after free\n");
- p = kzalloc(128, GFP_KERNEL);
- kfree(p);
- *p = 0x78;
- printk(KERN_ERR "1. kmalloc-128: Clobber first word 0x78->0x%p\n\n", p);
- validate_slab_cache(kmalloc_caches + 7);
+ case CPU_UP_CANCELED:
+ case CPU_UP_CANCELED_FROZEN:
+ case CPU_DEAD:
+ case CPU_DEAD_FROZEN:
+ down_read(&slub_lock);
+ list_for_each_entry(s, &slab_caches, list) {
+ struct kmem_cache_cpu *c = get_cpu_slab(s, cpu);
+
+ local_irq_save(flags);
+ __flush_cpu_slab(s, cpu);
+ local_irq_restore(flags);
+ free_kmem_cache_cpu(c, cpu);
+ s->cpu_slab[cpu] = NULL;
+ }
+ up_read(&slub_lock);
+ break;
+ default:
+ break;
+ }
+ return NOTIFY_OK;
+}
- p = kzalloc(256, GFP_KERNEL);
- kfree(p);
- p[50] = 0x9a;
- printk(KERN_ERR "\n2. kmalloc-256: Clobber 50th byte 0x9a->0x%p\n\n", p);
- validate_slab_cache(kmalloc_caches + 8);
+static struct notifier_block __cpuinitdata slab_notifier =
+ { &slab_cpuup_callback, NULL, 0 };
- p = kzalloc(512, GFP_KERNEL);
- kfree(p);
- p[512] = 0xab;
- printk(KERN_ERR "\n3. kmalloc-512: Clobber redzone 0xab->0x%p\n\n", p);
- validate_slab_cache(kmalloc_caches + 9);
-}
-#else
-static void resiliency_test(void) {};
#endif
void *__kmalloc_track_caller(size_t size, gfp_t gfpflags, void *caller)
{
- struct kmem_cache *s = get_slab(size, gfpflags);
+ struct kmem_cache *s;
- if (!s)
- return NULL;
+ if (unlikely(size > PAGE_SIZE / 2))
+ return (void *)__get_free_pages(gfpflags | __GFP_COMP,
+ get_order(size));
+ s = get_slab(size, gfpflags);
+
+ if (unlikely(ZERO_OR_NULL_PTR(s)))
+ return s;
return slab_alloc(s, gfpflags, -1, caller);
}
void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags,
int node, void *caller)
{
- struct kmem_cache *s = get_slab(size, gfpflags);
+ struct kmem_cache *s;
- if (!s)
- return NULL;
+ if (unlikely(size > PAGE_SIZE / 2))
+ return (void *)__get_free_pages(gfpflags | __GFP_COMP,
+ get_order(size));
+ s = get_slab(size, gfpflags);
+
+ if (unlikely(ZERO_OR_NULL_PTR(s)))
+ return s;
return slab_alloc(s, gfpflags, node, caller);
}
-#ifdef CONFIG_SYSFS
+static unsigned long count_partial(struct kmem_cache_node *n)
+{
+ unsigned long flags;
+ unsigned long x = 0;
+ struct page *page;
+
+ spin_lock_irqsave(&n->list_lock, flags);
+ list_for_each_entry(page, &n->partial, lru)
+ x += page->inuse;
+ spin_unlock_irqrestore(&n->list_lock, flags);
+ return x;
+}
-static int validate_slab(struct kmem_cache *s, struct page *page)
+#if defined(CONFIG_SYSFS) && defined(CONFIG_SLUB_DEBUG)
+static int validate_slab(struct kmem_cache *s, struct page *page,
+ unsigned long *map)
{
void *p;
void *addr = page_address(page);
- unsigned long map[BITS_TO_LONGS(s->objects)];
if (!check_slab(s, page) ||
!on_freelist(s, page, NULL))
/* Now we know that a valid freelist exists */
bitmap_zero(map, s->objects);
- for(p = page->freelist; p; p = get_freepointer(s, p)) {
- set_bit((p - addr) / s->size, map);
+ for_each_free_object(p, s, page->freelist) {
+ set_bit(slab_index(p, s, addr), map);
if (!check_object(s, page, p, 0))
return 0;
}
- for(p = addr; p < addr + s->objects * s->size; p += s->size)
- if (!test_bit((p - addr) / s->size, map))
+ for_each_object(p, s, addr)
+ if (!test_bit(slab_index(p, s, addr), map))
if (!check_object(s, page, p, 1))
return 0;
return 1;
}
-static void validate_slab_slab(struct kmem_cache *s, struct page *page)
+static void validate_slab_slab(struct kmem_cache *s, struct page *page,
+ unsigned long *map)
{
if (slab_trylock(page)) {
- validate_slab(s, page);
+ validate_slab(s, page, map);
slab_unlock(page);
} else
printk(KERN_INFO "SLUB %s: Skipped busy slab 0x%p\n",
s->name, page);
if (s->flags & DEBUG_DEFAULT_FLAGS) {
- if (!PageError(page))
- printk(KERN_ERR "SLUB %s: PageError not set "
+ if (!SlabDebug(page))
+ printk(KERN_ERR "SLUB %s: SlabDebug not set "
"on slab 0x%p\n", s->name, page);
} else {
- if (PageError(page))
- printk(KERN_ERR "SLUB %s: PageError set on "
+ if (SlabDebug(page))
+ printk(KERN_ERR "SLUB %s: SlabDebug set on "
"slab 0x%p\n", s->name, page);
}
}
-static int validate_slab_node(struct kmem_cache *s, struct kmem_cache_node *n)
+static int validate_slab_node(struct kmem_cache *s,
+ struct kmem_cache_node *n, unsigned long *map)
{
unsigned long count = 0;
struct page *page;
spin_lock_irqsave(&n->list_lock, flags);
list_for_each_entry(page, &n->partial, lru) {
- validate_slab_slab(s, page);
+ validate_slab_slab(s, page, map);
count++;
}
if (count != n->nr_partial)
goto out;
list_for_each_entry(page, &n->full, lru) {
- validate_slab_slab(s, page);
+ validate_slab_slab(s, page, map);
count++;
}
if (count != atomic_long_read(&n->nr_slabs))
return count;
}
-static unsigned long validate_slab_cache(struct kmem_cache *s)
+static long validate_slab_cache(struct kmem_cache *s)
{
int node;
unsigned long count = 0;
+ unsigned long *map = kmalloc(BITS_TO_LONGS(s->objects) *
+ sizeof(unsigned long), GFP_KERNEL);
+
+ if (!map)
+ return -ENOMEM;
flush_all(s);
- for_each_online_node(node) {
+ for_each_node_state(node, N_NORMAL_MEMORY) {
struct kmem_cache_node *n = get_node(s, node);
- count += validate_slab_node(s, n);
+ count += validate_slab_node(s, n, map);
}
+ kfree(map);
return count;
}
+#ifdef SLUB_RESILIENCY_TEST
+static void resiliency_test(void)
+{
+ u8 *p;
+
+ printk(KERN_ERR "SLUB resiliency testing\n");
+ printk(KERN_ERR "-----------------------\n");
+ printk(KERN_ERR "A. Corruption after allocation\n");
+
+ p = kzalloc(16, GFP_KERNEL);
+ p[16] = 0x12;
+ printk(KERN_ERR "\n1. kmalloc-16: Clobber Redzone/next pointer"
+ " 0x12->0x%p\n\n", p + 16);
+
+ validate_slab_cache(kmalloc_caches + 4);
+
+ /* Hmmm... The next two are dangerous */
+ p = kzalloc(32, GFP_KERNEL);
+ p[32 + sizeof(void *)] = 0x34;
+ printk(KERN_ERR "\n2. kmalloc-32: Clobber next pointer/next slab"
+ " 0x34 -> -0x%p\n", p);
+ printk(KERN_ERR "If allocated object is overwritten then not detectable\n\n");
+
+ validate_slab_cache(kmalloc_caches + 5);
+ p = kzalloc(64, GFP_KERNEL);
+ p += 64 + (get_cycles() & 0xff) * sizeof(void *);
+ *p = 0x56;
+ printk(KERN_ERR "\n3. kmalloc-64: corrupting random byte 0x56->0x%p\n",
+ p);
+ printk(KERN_ERR "If allocated object is overwritten then not detectable\n\n");
+ validate_slab_cache(kmalloc_caches + 6);
+
+ printk(KERN_ERR "\nB. Corruption after free\n");
+ p = kzalloc(128, GFP_KERNEL);
+ kfree(p);
+ *p = 0x78;
+ printk(KERN_ERR "1. kmalloc-128: Clobber first word 0x78->0x%p\n\n", p);
+ validate_slab_cache(kmalloc_caches + 7);
+
+ p = kzalloc(256, GFP_KERNEL);
+ kfree(p);
+ p[50] = 0x9a;
+ printk(KERN_ERR "\n2. kmalloc-256: Clobber 50th byte 0x9a->0x%p\n\n", p);
+ validate_slab_cache(kmalloc_caches + 8);
+
+ p = kzalloc(512, GFP_KERNEL);
+ kfree(p);
+ p[512] = 0xab;
+ printk(KERN_ERR "\n3. kmalloc-512: Clobber redzone 0xab->0x%p\n\n", p);
+ validate_slab_cache(kmalloc_caches + 9);
+}
+#else
+static void resiliency_test(void) {};
+#endif
+
/*
* Generate lists of code addresses where slabcache objects are allocated
* and freed.
struct location {
unsigned long count;
void *addr;
+ long long sum_time;
+ long min_time;
+ long max_time;
+ long min_pid;
+ long max_pid;
+ cpumask_t cpus;
+ nodemask_t nodes;
};
struct loc_track {
get_order(sizeof(struct location) * t->max));
}
-static int alloc_loc_track(struct loc_track *t, unsigned long max)
+static int alloc_loc_track(struct loc_track *t, unsigned long max, gfp_t flags)
{
struct location *l;
int order;
- if (!max)
- max = PAGE_SIZE / sizeof(struct location);
-
order = get_order(sizeof(struct location) * max);
- l = (void *)__get_free_pages(GFP_KERNEL, order);
-
+ l = (void *)__get_free_pages(flags, order);
if (!l)
return 0;
}
static int add_location(struct loc_track *t, struct kmem_cache *s,
- void *addr)
+ const struct track *track)
{
long start, end, pos;
struct location *l;
void *caddr;
+ unsigned long age = jiffies - track->when;
start = -1;
end = t->count;
break;
caddr = t->loc[pos].addr;
- if (addr == caddr) {
- t->loc[pos].count++;
+ if (track->addr == caddr) {
+
+ l = &t->loc[pos];
+ l->count++;
+ if (track->when) {
+ l->sum_time += age;
+ if (age < l->min_time)
+ l->min_time = age;
+ if (age > l->max_time)
+ l->max_time = age;
+
+ if (track->pid < l->min_pid)
+ l->min_pid = track->pid;
+ if (track->pid > l->max_pid)
+ l->max_pid = track->pid;
+
+ cpu_set(track->cpu, l->cpus);
+ }
+ node_set(page_to_nid(virt_to_page(track)), l->nodes);
return 1;
}
- if (addr < caddr)
+ if (track->addr < caddr)
end = pos;
else
start = pos;
/*
* Not found. Insert new tracking element.
*/
- if (t->count >= t->max && !alloc_loc_track(t, 2 * t->max))
+ if (t->count >= t->max && !alloc_loc_track(t, 2 * t->max, GFP_ATOMIC))
return 0;
l = t->loc + pos;
(t->count - pos) * sizeof(struct location));
t->count++;
l->count = 1;
- l->addr = addr;
+ l->addr = track->addr;
+ l->sum_time = age;
+ l->min_time = age;
+ l->max_time = age;
+ l->min_pid = track->pid;
+ l->max_pid = track->pid;
+ cpus_clear(l->cpus);
+ cpu_set(track->cpu, l->cpus);
+ nodes_clear(l->nodes);
+ node_set(page_to_nid(virt_to_page(track)), l->nodes);
return 1;
}
struct page *page, enum track_item alloc)
{
void *addr = page_address(page);
- unsigned long map[BITS_TO_LONGS(s->objects)];
+ DECLARE_BITMAP(map, s->objects);
void *p;
bitmap_zero(map, s->objects);
- for (p = page->freelist; p; p = get_freepointer(s, p))
- set_bit((p - addr) / s->size, map);
+ for_each_free_object(p, s, page->freelist)
+ set_bit(slab_index(p, s, addr), map);
- for (p = addr; p < addr + s->objects * s->size; p += s->size)
- if (!test_bit((p - addr) / s->size, map)) {
- void *addr = get_track(s, p, alloc)->addr;
-
- add_location(t, s, addr);
- }
+ for_each_object(p, s, addr)
+ if (!test_bit(slab_index(p, s, addr), map))
+ add_location(t, s, get_track(s, p, alloc));
}
static int list_locations(struct kmem_cache *s, char *buf,
{
int n = 0;
unsigned long i;
- struct loc_track t;
+ struct loc_track t = { 0, 0, NULL };
int node;
- t.count = 0;
- t.max = 0;
+ if (!alloc_loc_track(&t, PAGE_SIZE / sizeof(struct location),
+ GFP_TEMPORARY))
+ return sprintf(buf, "Out of memory\n");
/* Push back cpu slabs */
flush_all(s);
- for_each_online_node(node) {
+ for_each_node_state(node, N_NORMAL_MEMORY) {
struct kmem_cache_node *n = get_node(s, node);
unsigned long flags;
struct page *page;
- if (!atomic_read(&n->nr_slabs))
+ if (!atomic_long_read(&n->nr_slabs))
continue;
spin_lock_irqsave(&n->list_lock, flags);
}
for (i = 0; i < t.count; i++) {
- void *addr = t.loc[i].addr;
+ struct location *l = &t.loc[i];
if (n > PAGE_SIZE - 100)
break;
- n += sprintf(buf + n, "%7ld ", t.loc[i].count);
- if (addr)
- n += sprint_symbol(buf + n, (unsigned long)t.loc[i].addr);
+ n += sprintf(buf + n, "%7ld ", l->count);
+
+ if (l->addr)
+ n += sprint_symbol(buf + n, (unsigned long)l->addr);
else
n += sprintf(buf + n, "<not-available>");
+
+ if (l->sum_time != l->min_time) {
+ unsigned long remainder;
+
+ n += sprintf(buf + n, " age=%ld/%ld/%ld",
+ l->min_time,
+ div_long_long_rem(l->sum_time, l->count, &remainder),
+ l->max_time);
+ } else
+ n += sprintf(buf + n, " age=%ld",
+ l->min_time);
+
+ if (l->min_pid != l->max_pid)
+ n += sprintf(buf + n, " pid=%ld-%ld",
+ l->min_pid, l->max_pid);
+ else
+ n += sprintf(buf + n, " pid=%ld",
+ l->min_pid);
+
+ if (num_online_cpus() > 1 && !cpus_empty(l->cpus) &&
+ n < PAGE_SIZE - 60) {
+ n += sprintf(buf + n, " cpus=");
+ n += cpulist_scnprintf(buf + n, PAGE_SIZE - n - 50,
+ l->cpus);
+ }
+
+ if (num_online_nodes() > 1 && !nodes_empty(l->nodes) &&
+ n < PAGE_SIZE - 60) {
+ n += sprintf(buf + n, " nodes=");
+ n += nodelist_scnprintf(buf + n, PAGE_SIZE - n - 50,
+ l->nodes);
+ }
+
n += sprintf(buf + n, "\n");
}
return n;
}
-static unsigned long count_partial(struct kmem_cache_node *n)
-{
- unsigned long flags;
- unsigned long x = 0;
- struct page *page;
-
- spin_lock_irqsave(&n->list_lock, flags);
- list_for_each_entry(page, &n->partial, lru)
- x += page->inuse;
- spin_unlock_irqrestore(&n->list_lock, flags);
- return x;
-}
-
enum slab_stat_type {
SL_FULL,
SL_PARTIAL,
per_cpu = nodes + nr_node_ids;
for_each_possible_cpu(cpu) {
- struct page *page = s->cpu_slab[cpu];
+ struct page *page;
int node;
+ struct kmem_cache_cpu *c = get_cpu_slab(s, cpu);
+
+ if (!c)
+ continue;
+ page = c->page;
+ node = c->node;
+ if (node < 0)
+ continue;
if (page) {
- node = page_to_nid(page);
if (flags & SO_CPU) {
int x = 0;
}
}
- for_each_online_node(node) {
+ for_each_node_state(node, N_NORMAL_MEMORY) {
struct kmem_cache_node *n = get_node(s, node);
if (flags & SO_PARTIAL) {
}
if (flags & SO_FULL) {
- int full_slabs = atomic_read(&n->nr_slabs)
+ int full_slabs = atomic_long_read(&n->nr_slabs)
- per_cpu[node]
- n->nr_partial;
x = sprintf(buf, "%lu", total);
#ifdef CONFIG_NUMA
- for_each_online_node(node)
+ for_each_node_state(node, N_NORMAL_MEMORY)
if (nodes[node])
x += sprintf(buf + x, " N%d=%lu",
node, nodes[node]);
int node;
int cpu;
- for_each_possible_cpu(cpu)
- if (s->cpu_slab[cpu])
+ for_each_possible_cpu(cpu) {
+ struct kmem_cache_cpu *c = get_cpu_slab(s, cpu);
+
+ if (c && c->page)
return 1;
+ }
- for_each_node(node) {
+ for_each_online_node(node) {
struct kmem_cache_node *n = get_node(s, node);
- if (n->nr_partial || atomic_read(&n->nr_slabs))
+ if (!n)
+ continue;
+
+ if (n->nr_partial || atomic_long_read(&n->nr_slabs))
return 1;
}
return 0;
}
SLAB_ATTR_RO(ctor);
-static ssize_t dtor_show(struct kmem_cache *s, char *buf)
-{
- if (s->dtor) {
- int n = sprint_symbol(buf, (unsigned long)s->dtor);
-
- return n + sprintf(buf + n, "\n");
- }
- return 0;
-}
-SLAB_ATTR_RO(dtor);
-
static ssize_t aliases_show(struct kmem_cache *s, char *buf)
{
return sprintf(buf, "%d\n", s->refcount - 1);
static ssize_t validate_store(struct kmem_cache *s,
const char *buf, size_t length)
{
- if (buf[0] == '1')
- validate_slab_cache(s);
- else
- return -EINVAL;
- return length;
+ int ret = -EINVAL;
+
+ if (buf[0] == '1') {
+ ret = validate_slab_cache(s);
+ if (ret >= 0)
+ ret = length;
+ }
+ return ret;
}
SLAB_ATTR(validate);
&partial_attr.attr,
&cpu_slabs_attr.attr,
&ctor_attr.attr,
- &dtor_attr.attr,
&aliases_attr.attr,
&align_attr.attr,
&sanity_checks_attr.attr,
.filter = uevent_filter,
};
-decl_subsys(slab, &slab_ktype, &slab_uevent_ops);
+static struct kset *slab_kset;
#define ID_STR_LENGTH 64
* This is typically the case for debug situations. In that
* case we can catch duplicate names easily.
*/
- sysfs_remove_link(&slab_subsys.kobj, s->name);
+ sysfs_remove_link(&slab_kset->kobj, s->name);
name = s->name;
} else {
/*
name = create_unique_id(s);
}
- kobj_set_kset_s(s, slab_subsys);
- kobject_set_name(&s->kobj, name);
- kobject_init(&s->kobj);
- err = kobject_add(&s->kobj);
- if (err)
+ s->kobj.kset = slab_kset;
+ err = kobject_init_and_add(&s->kobj, &slab_ktype, NULL, name);
+ if (err) {
+ kobject_put(&s->kobj);
return err;
+ }
err = sysfs_create_group(&s->kobj, &slab_attr_group);
if (err)
struct saved_alias *next;
};
-struct saved_alias *alias_list;
+static struct saved_alias *alias_list;
static int sysfs_slab_alias(struct kmem_cache *s, const char *name)
{
/*
* If we have a leftover link then remove it.
*/
- sysfs_remove_link(&slab_subsys.kobj, name);
- return sysfs_create_link(&slab_subsys.kobj,
- &s->kobj, name);
+ sysfs_remove_link(&slab_kset->kobj, name);
+ return sysfs_create_link(&slab_kset->kobj, &s->kobj, name);
}
al = kmalloc(sizeof(struct saved_alias), GFP_KERNEL);
static int __init slab_sysfs_init(void)
{
- struct list_head *h;
+ struct kmem_cache *s;
int err;
- err = subsystem_register(&slab_subsys);
- if (err) {
+ slab_kset = kset_create_and_add("slab", &slab_uevent_ops, kernel_kobj);
+ if (!slab_kset) {
printk(KERN_ERR "Cannot register slab subsystem.\n");
return -ENOSYS;
}
slab_state = SYSFS;
- list_for_each(h, &slab_caches) {
- struct kmem_cache *s =
- container_of(h, struct kmem_cache, list);
-
+ list_for_each_entry(s, &slab_caches, list) {
err = sysfs_slab_add(s);
- BUG_ON(err);
+ if (err)
+ printk(KERN_ERR "SLUB: Unable to add boot slab %s"
+ " to sysfs\n", s->name);
}
while (alias_list) {
alias_list = alias_list->next;
err = sysfs_slab_alias(al->s, al->name);
- BUG_ON(err);
+ if (err)
+ printk(KERN_ERR "SLUB: Unable to add boot slab alias"
+ " %s to sysfs\n", s->name);
kfree(al);
}
__initcall(slab_sysfs_init);
#endif
+
+/*
+ * The /proc/slabinfo ABI
+ */
+#ifdef CONFIG_SLABINFO
+
+ssize_t slabinfo_write(struct file *file, const char __user * buffer,
+ size_t count, loff_t *ppos)
+{
+ return -EINVAL;
+}
+
+
+static void print_slabinfo_header(struct seq_file *m)
+{
+ seq_puts(m, "slabinfo - version: 2.1\n");
+ seq_puts(m, "# name <active_objs> <num_objs> <objsize> "
+ "<objperslab> <pagesperslab>");
+ seq_puts(m, " : tunables <limit> <batchcount> <sharedfactor>");
+ seq_puts(m, " : slabdata <active_slabs> <num_slabs> <sharedavail>");
+ seq_putc(m, '\n');
+}
+
+static void *s_start(struct seq_file *m, loff_t *pos)
+{
+ loff_t n = *pos;
+
+ down_read(&slub_lock);
+ if (!n)
+ print_slabinfo_header(m);
+
+ return seq_list_start(&slab_caches, *pos);
+}
+
+static void *s_next(struct seq_file *m, void *p, loff_t *pos)
+{
+ return seq_list_next(p, &slab_caches, pos);
+}
+
+static void s_stop(struct seq_file *m, void *p)
+{
+ up_read(&slub_lock);
+}
+
+static int s_show(struct seq_file *m, void *p)
+{
+ unsigned long nr_partials = 0;
+ unsigned long nr_slabs = 0;
+ unsigned long nr_inuse = 0;
+ unsigned long nr_objs;
+ struct kmem_cache *s;
+ int node;
+
+ s = list_entry(p, struct kmem_cache, list);
+
+ for_each_online_node(node) {
+ struct kmem_cache_node *n = get_node(s, node);
+
+ if (!n)
+ continue;
+
+ nr_partials += n->nr_partial;
+ nr_slabs += atomic_long_read(&n->nr_slabs);
+ nr_inuse += count_partial(n);
+ }
+
+ nr_objs = nr_slabs * s->objects;
+ nr_inuse += (nr_slabs - nr_partials) * s->objects;
+
+ seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d", s->name, nr_inuse,
+ nr_objs, s->size, s->objects, (1 << s->order));
+ seq_printf(m, " : tunables %4u %4u %4u", 0, 0, 0);
+ seq_printf(m, " : slabdata %6lu %6lu %6lu", nr_slabs, nr_slabs,
+ 0UL);
+ seq_putc(m, '\n');
+ return 0;
+}
+
+const struct seq_operations slabinfo_op = {
+ .start = s_start,
+ .next = s_next,
+ .stop = s_stop,
+ .show = s_show,
+};
+
+#endif /* CONFIG_SLABINFO */
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff