Commit 70d71228 authored by Christoph Lameter's avatar Christoph Lameter Committed by Linus Torvalds
Browse files

slub: remove object activities out of checking functions 



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: default avatarChristoph Lameter <clameter@sgi.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 2086d26a

mm/slub.c

+47 −61
Original line number Diff line number Diff line
@@ -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);

}
@@ -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;
@@ -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 */
@@ -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;
@@ -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,

		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;

}
@@ -702,15 +697,13 @@ 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)
@@ -718,17 +711,8 @@ static int alloc_object_checks(struct kmem_cache *s, struct page *page, 


	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)) {

		/*
@@ -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;

	}
@@ -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;
@@ -1294,6 +1265,13 @@ debug: 
		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;

}
@@ -1376,6 +1354,14 @@ debug: 
		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;

}

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