#define ARCH_SLAB_MINALIGN __alignof__(unsigned long long)
#endif
+/*
+ * The page->inuse field is 16 bit thus we have this limitation
+ */
+#define MAX_OBJECTS_PER_SLAB 65535
+
/* Internal SLUB flags */
#define __OBJECT_POISON 0x80000000 /* Poison object */
/*
* 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;
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]);
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_trailer(struct kmem_cache *s, u8 *p)
+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 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 void restore_bytes(struct kmem_cache *s, char *message, u8 data,
+ void *from, void *to)
+{
+ slab_fix(s, "Restoring 0x%p-0x%p=0x%x\n", from, to - 1, data);
+ memset(from, data, to - from);
+}
+
+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;
+
+ end = start + bytes;
+ while (end > fault && end[-1] == value)
+ end--;
+
+ 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));
+ slab_err(s, page, "Not a valid slab 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, "Corrupted offset %lu",
+ (unsigned long)(page->offset * sizeof(void *)));
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 */
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;
}
-static void trace(struct kmem_cache *s, struct page *page, void *object, int alloc)
+static int __init setup_slub_debug(char *str)
{
- 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);
+ slub_debug = DEBUG_DEFAULT_FLAGS;
+ if (*str++ != '=' || !*str)
+ /*
+ * No options specified. Switch on full debugging.
+ */
+ goto out;
- if (!alloc)
- print_section("Object", (void *)object, s->objsize);
+ if (*str == ',')
+ /*
+ * No options but restriction on slabs. This means full
+ * debugging for slabs matching a pattern.
+ */
+ goto check_slabs;
- dump_stack();
- }
-}
+ slub_debug = 0;
+ if (*str == '-')
+ /*
+ * Switch off all debugging measures.
+ */
+ goto out;
-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);
- }
+ /*
+ * 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;
}
* Debugging or ctor may create a need to move the free
* pointer. Fail if this happens.
*/
- if (s->size >= 65535 * sizeof(void *)) {
+ if (s->objsize >= 65535 * sizeof(void *)) {
BUG_ON(s->flags & (SLAB_RED_ZONE | SLAB_POISON |
SLAB_STORE_USER | SLAB_DESTROY_BY_RCU));
BUG_ON(s->ctor);
s->flags |= slub_debug;
}
#else
+static inline void setup_object_debug(struct kmem_cache *s,
+ struct page *page, void *object) {}
-static inline int alloc_object_checks(struct kmem_cache *s,
- struct page *page, void *object) { return 0; }
+static inline int alloc_debug_processing(struct kmem_cache *s,
+ struct page *page, void *object, void *addr) { return 0; }
-static inline int free_object_checks(struct kmem_cache *s,
- struct page *page, void *object) { return 0; }
+static inline int free_debug_processing(struct kmem_cache *s,
+ struct page *page, void *object, void *addr) { return 0; }
-static inline void add_full(struct kmem_cache_node *n, struct page *page) {}
-static inline void remove_full(struct kmem_cache *s, struct page *page) {}
-static inline void trace(struct kmem_cache *s, struct page *page,
- void *object, int alloc) {}
-static inline void init_object(struct kmem_cache *s,
- void *object, int active) {}
-static inline void init_tracking(struct kmem_cache *s, void *object) {}
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 set_track(struct kmem_cache *s, void *object,
- enum track_item alloc, void *addr) {}
+static inline void add_full(struct kmem_cache_node *n, struct page *page) {}
static inline void kmem_cache_open_debug_check(struct kmem_cache *s) {}
#define slub_debug 0
#endif
static void setup_object(struct kmem_cache *s, struct page *page,
void *object)
{
- if (SlabDebug(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(object, s, 0);
}
static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node)
return NULL;
debug:
object = page->freelist;
- if (!alloc_object_checks(s, page, object))
+ if (!alloc_debug_processing(s, page, object, addr))
goto another_slab;
- if (s->flags & SLAB_STORE_USER)
- set_track(s, object, TRACK_ALLOC, addr);
- trace(s, page, object, 1);
- init_object(s, object, 1);
page->inuse++;
page->freelist = object[page->offset];
return;
debug:
- if (!free_object_checks(s, page, x))
+ if (!free_debug_processing(s, page, x, addr))
goto out_unlock;
- if (!SlabFrozen(page) && !page->freelist)
- remove_full(s, page);
- if (s->flags & SLAB_STORE_USER)
- set_track(s, x, TRACK_FREE, addr);
- trace(s, page, object, 0);
- init_object(s, object, 0);
goto checks_ok;
}
{
int order;
int rem;
+ int min_order = slub_min_order;
- for (order = max(slub_min_order,
+ /*
+ * If we would create too many object per slab then reduce
+ * the slab order even if it goes below slub_min_order.
+ */
+ while (min_order > 0 &&
+ (PAGE_SIZE << min_order) >= MAX_OBJECTS_PER_SLAB * size)
+ min_order--;
+
+ for (order = max(min_order,
fls(min_objects * size - 1) - PAGE_SHIFT);
order <= max_order; order++) {
if (rem <= slab_size / fract_leftover)
break;
+ /* If the next size is too high then exit now */
+ if (slab_size * 2 >= MAX_OBJECTS_PER_SLAB * size)
+ break;
}
return order;
BUG_ON(kmalloc_caches->size < sizeof(struct kmem_cache_node));
page = new_slab(kmalloc_caches, gfpflags | GFP_THISNODE, node);
- /* new_slab() disables interupts */
- local_irq_enable();
BUG_ON(!page);
n = page->freelist;
page->inuse++;
kmalloc_caches->node[node] = n;
init_object(kmalloc_caches, n, 1);
+ init_tracking(kmalloc_caches, n);
init_kmem_cache_node(n);
atomic_long_inc(&n->nr_slabs);
add_partial(n, page);
+
+ /*
+ * new_slab() disables interupts. If we do not reenable interrupts here
+ * then bootup would continue with interrupts disabled.
+ */
+ local_irq_enable();
return n;
}
*/
s->inuse = size;
-#ifdef CONFIG_SLUB_DEBUG
if (((flags & (SLAB_DESTROY_BY_RCU | SLAB_POISON)) ||
s->ctor)) {
/*
size += sizeof(void *);
}
+#ifdef CONFIG_SLUB_DEBUG
if (flags & SLAB_STORE_USER)
/*
* Need to store information about allocs and frees after
* 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)
+ if (!s->objects || s->objects > MAX_OBJECTS_PER_SLAB)
return 0;
return 1;
s->offset, flags);
return 0;
}
-EXPORT_SYMBOL(kmem_cache_open);
/*
* Check if a given pointer is valid
if (s)
return slab_alloc(s, flags, -1, __builtin_return_address(0));
- return NULL;
+ return ZERO_SIZE_PTR;
}
EXPORT_SYMBOL(__kmalloc);
if (s)
return slab_alloc(s, flags, node, __builtin_return_address(0));
- return NULL;
+ return ZERO_SIZE_PTR;
}
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;
+ if (object == ZERO_SIZE_PTR)
+ return 0;
+
+ page = get_object_page(object);
BUG_ON(!page);
s = page->slab;
BUG_ON(!s);
struct kmem_cache *s;
struct page *page;
- if (!x)
+ /*
+ * This has to be an unsigned comparison. According to Linus
+ * some gcc version treat a pointer as a signed entity. Then
+ * this comparison would be true for all "negative" pointers
+ * (which would cover the whole upper half of the address space).
+ */
+ if ((unsigned long)x <= (unsigned long)ZERO_SIZE_PTR)
return;
page = virt_to_head_page(x);
}
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)
-{
- void *ret;
- size_t ks;
-
- if (unlikely(!p))
- return kmalloc(new_size, flags);
-
- if (unlikely(!new_size)) {
- kfree(p);
- return NULL;
- }
-
- ks = ksize(p);
- if (ks >= new_size)
- return (void *)p;
-
- ret = kmalloc(new_size, flags);
- if (ret) {
- memcpy(ret, p, min(new_size, ks));
- kfree(p);
- }
- return ret;
-}
-EXPORT_SYMBOL(krealloc);
-
/********************************************************************
* Basic setup of slabs
*******************************************************************/
void __init kmem_cache_init(void)
{
int i;
+ int caches = 0;
#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++;
#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 <= KMALLOC_SHIFT_HIGH; i++) {
create_kmalloc_cache(&kmalloc_caches[i],
"kmalloc", 1 << i, GFP_KERNEL);
+ caches++;
+ }
slab_state = UP;
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 (s->ctor)
return 1;
+ /*
+ * We may have set a slab to be unmergeable during bootstrap.
+ */
+ if (s->refcount < 0)
+ return 1;
+
return 0;
}
size_t align, unsigned long flags,
void (*ctor)(void *, struct kmem_cache *, unsigned long))
{
- struct list_head *h;
+ struct kmem_cache *s;
if (slub_nomerge || (flags & SLUB_NEVER_MERGE))
return NULL;
align = calculate_alignment(flags, align, size);
size = ALIGN(size, align);
- 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;
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.
unsigned long action, void *hcpu)
{
long cpu = (long)hcpu;
+ struct kmem_cache *s;
+ unsigned long flags;
switch (action) {
case CPU_UP_CANCELED:
case CPU_UP_CANCELED_FROZEN:
case CPU_DEAD:
case CPU_DEAD_FROZEN:
- for_all_slabs(__flush_cpu_slab, cpu);
+ down_read(&slub_lock);
+ list_for_each_entry(s, &slab_caches, list) {
+ local_irq_save(flags);
+ __flush_cpu_slab(s, cpu);
+ local_irq_restore(flags);
+ }
+ up_read(&slub_lock);
break;
default:
break;
struct kmem_cache *s = get_slab(size, gfpflags);
if (!s)
- return NULL;
+ return ZERO_SIZE_PTR;
return slab_alloc(s, gfpflags, -1, caller);
}
struct kmem_cache *s = get_slab(size, gfpflags);
if (!s)
- return NULL;
+ return ZERO_SIZE_PTR;
return slab_alloc(s, gfpflags, node, caller);
}
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;
/*
* 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;
{
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_KERNEL))
+ return sprintf(buf, "Out of memory\n");
/* Push back cpu slabs */
flush_all(s);
n += sprintf(buf + n, " pid=%ld",
l->min_pid);
- if (num_online_cpus() > 1 && !cpus_empty(l->cpus)) {
+ 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)) {
+ 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);
static int __init slab_sysfs_init(void)
{
- struct list_head *h;
+ struct kmem_cache *s;
int err;
err = subsystem_register(&slab_subsys);
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);
}
Code Review / linux-2.6.git / blobdiff