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slub: remove object activities out of checking functions
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Make sure that the check function really only check things and do not perform
activities.  Extract the tracing and object seeding out of the two check
functions and place them into slab_alloc and slab_free

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Christoph Lameter authored and Linus Torvalds committed May 7, 2007
1 parent 2086d26 commit 70d7122
Showing 1 changed file with 47 additions and 61 deletions.
108 changes: 47 additions & 61 deletions mm/slub.c
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Original file line number Diff line number Diff line change
Expand Up @@ -459,7 +459,7 @@ static int check_valid_pointer(struct kmem_cache *s, struct page *page,
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",
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);
}
Expand Down Expand Up @@ -506,9 +506,7 @@ static int slab_pad_check(struct kmem_cache *s, struct page *page)
return 1;

if (!check_bytes(p + length, POISON_INUSE, remainder)) {
printk(KERN_ERR "SLUB: %s slab 0x%p: Padding fails check\n",
s->name, p);
dump_stack();
slab_err(s, page, "Padding check failed");
restore_bytes(s, "slab padding", POISON_INUSE, p + length,
p + length + remainder);
return 0;
Expand Down Expand Up @@ -594,30 +592,25 @@ static int check_slab(struct kmem_cache *s, struct page *page)
VM_BUG_ON(!irqs_disabled());

if (!PageSlab(page)) {
printk(KERN_ERR "SLUB: %s Not a valid slab page @0x%p "
"flags=%lx mapping=0x%p count=%d \n",
s->name, page, page->flags, page->mapping,
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) {
printk(KERN_ERR "SLUB: %s Corrupted offset %lu in slab @0x%p"
" flags=0x%lx mapping=0x%p count=%d\n",
s->name,
slab_err(s, page, "Corrupted offset %lu flags=0x%lx "
"mapping=0x%p count=%d",
(unsigned long)(page->offset * sizeof(void *)),
page,
page->flags,
page->mapping,
page_count(page));
dump_stack();
return 0;
}
if (page->inuse > s->objects) {
printk(KERN_ERR "SLUB: %s Inuse %u > max %u in slab "
"page @0x%p flags=%lx mapping=0x%p count=%d\n",
s->name, page->inuse, s->objects, page, page->flags,
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));
dump_stack();
return 0;
}
/* Slab_pad_check fixes things up after itself */
Expand Down Expand Up @@ -646,12 +639,13 @@ static int on_freelist(struct kmem_cache *s, struct page *page, void *search)
set_freepointer(s, object, NULL);
break;
} else {
printk(KERN_ERR "SLUB: %s slab 0x%p "
"freepointer 0x%p corrupted.\n",
s->name, page, fp);
dump_stack();
slab_err(s, page, "Freepointer 0x%p corrupt",
fp);
page->freelist = NULL;
page->inuse = s->objects;
printk(KERN_ERR "@@@ SLUB %s: Freelist "
"cleared. Slab 0x%p\n",
s->name, page);
return 0;
}
break;
Expand All @@ -662,11 +656,12 @@ static int on_freelist(struct kmem_cache *s, struct page *page, void *search)
}

if (page->inuse != s->objects - nr) {
printk(KERN_ERR "slab %s: page 0x%p wrong object count."
" counter is %d but counted were %d\n",
s->name, page, 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);
page->inuse = s->objects - nr;
printk(KERN_ERR "@@@ SLUB %s: Object count adjusted. "
"Slab @0x%p\n", s->name, page);
}
return search == NULL;
}
Expand Down Expand Up @@ -702,33 +697,22 @@ static int alloc_object_checks(struct kmem_cache *s, struct page *page,
goto bad;

if (object && !on_freelist(s, page, object)) {
printk(KERN_ERR "SLUB: %s Object 0x%p@0x%p "
"already allocated.\n",
s->name, object, page);
goto dump;
slab_err(s, page, "Object 0x%p already allocated", object);
goto bad;
}

if (!check_valid_pointer(s, page, object)) {
object_err(s, page, object, "Freelist Pointer check fails");
goto dump;
goto bad;
}

if (!object)
return 1;

if (!check_object(s, page, object, 0))
goto bad;
init_object(s, object, 1);

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();
}
return 1;
dump:
dump_stack();
bad:
if (PageSlab(page)) {
/*
Expand All @@ -753,15 +737,12 @@ static int free_object_checks(struct kmem_cache *s, struct page *page,
goto fail;

if (!check_valid_pointer(s, page, object)) {
printk(KERN_ERR "SLUB: %s slab 0x%p invalid "
"object pointer 0x%p\n",
s->name, page, object);
slab_err(s, page, "Invalid object pointer 0x%p", object);
goto fail;
}

if (on_freelist(s, page, object)) {
printk(KERN_ERR "SLUB: %s slab 0x%p object "
"0x%p already free.\n", s->name, page, object);
slab_err(s, page, "Object 0x%p already free", object);
goto fail;
}

Expand All @@ -770,32 +751,22 @@ static int free_object_checks(struct kmem_cache *s, struct page *page,

if (unlikely(s != page->slab)) {
if (!PageSlab(page))
printk(KERN_ERR "slab_free %s size %d: attempt to"
"free object(0x%p) outside of slab.\n",
s->name, s->size, object);
slab_err(s, page, "Attempt to free object(0x%p) "
"outside of slab", object);
else
if (!page->slab)
if (!page->slab) {
printk(KERN_ERR
"slab_free : no slab(NULL) for object 0x%p.\n",
"SLUB <none>: no slab for object 0x%p.\n",
object);
dump_stack();
}
else
printk(KERN_ERR "slab_free %s(%d): object at 0x%p"
" belongs to slab %s(%d)\n",
s->name, s->size, object,
page->slab->name, page->slab->size);
slab_err(s, page, "object at 0x%p belongs "
"to slab %s", object, page->slab->name);
goto fail;
}
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", object, s->objsize);
dump_stack();
}
init_object(s, object, 0);
return 1;
fail:
dump_stack();
printk(KERN_ERR "@@@ SLUB: %s slab 0x%p object at 0x%p not freed.\n",
s->name, page, object);
return 0;
Expand Down Expand Up @@ -1294,6 +1265,13 @@ static void *slab_alloc(struct kmem_cache *s,
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();
}
init_object(s, object, 1);
goto have_object;
}

Expand Down Expand Up @@ -1376,6 +1354,14 @@ static void slab_free(struct kmem_cache *s, struct page *page,
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;
}

Expand Down

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