Slab allocators: Drop support for destructors

[linux-2.6-omap-h63xx.git] / mm / slub.c

diff --git a/mm/slub.c b/mm/slub.c
index 5e3e8bc9838f8f30eb7a383447356e436737623c..022c1b4d74d4dfbf23350eeedaeacdffe95d33bb 100644 (file)
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -891,13 +891,13 @@ static void kmem_cache_open_debug_check(struct kmem_cache *s)
         * 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
+        * Debugging or ctor may create a need to move the free
         * pointer. Fail if this happens.
         */
        if (s->size >= 65535 * sizeof(void *)) {
                BUG_ON(s->flags & (SLAB_RED_ZONE | SLAB_POISON |
                                SLAB_STORE_USER | SLAB_DESTROY_BY_RCU));
-               BUG_ON(s->ctor || s->dtor);
+               BUG_ON(s->ctor);
        }
        else
                /*
@@ -1030,15 +1030,12 @@ static void __free_slab(struct kmem_cache *s, struct page *page)
 {
        int pages = 1 << s->order;
 
-       if (unlikely(SlabDebug(page) || s->dtor)) {
+       if (unlikely(SlabDebug(page))) {
                void *p;
 
                slab_pad_check(s, page);
-               for_each_object(p, s, page_address(page)) {
-                       if (s->dtor)
-                               s->dtor(p, s, 0);
+               for_each_object(p, s, page_address(page))
                        check_object(s, page, p, 0);
-               }
        }
 
        mod_zone_page_state(page_zone(page),
@@ -1871,7 +1868,7 @@ static int calculate_sizes(struct kmem_cache *s)
         * 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;
@@ -1901,7 +1898,7 @@ static int calculate_sizes(struct kmem_cache *s)
 
 #ifdef CONFIG_SLUB_DEBUG
        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
@@ -1970,13 +1967,11 @@ static int calculate_sizes(struct kmem_cache *s)
 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)(void *, struct kmem_cache *, unsigned long))
 {
        memset(s, 0, kmem_size);
        s->name = name;
        s->ctor = ctor;
-       s->dtor = dtor;
        s->objsize = size;
        s->flags = flags;
        s->align = align;
@@ -2161,7 +2156,7 @@ static struct kmem_cache *create_kmalloc_cache(struct kmem_cache *s,
 
        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);
@@ -2463,7 +2458,7 @@ static int slab_unmergeable(struct kmem_cache *s)
        if (slub_nomerge || (s->flags & SLUB_NEVER_MERGE))
                return 1;
 
-       if (s->ctor || s->dtor)
+       if (s->ctor)
                return 1;
 
        return 0;
@@ -2471,15 +2466,14 @@ static int slab_unmergeable(struct kmem_cache *s)
 
 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))
+               void (*ctor)(void *, struct kmem_cache *, unsigned long))
 {
        struct list_head *h;
 
        if (slub_nomerge || (flags & SLUB_NEVER_MERGE))
                return NULL;
 
-       if (ctor || dtor)
+       if (ctor)
                return NULL;
 
        size = ALIGN(size, sizeof(void *));
@@ -2521,8 +2515,9 @@ struct kmem_cache *kmem_cache_create(const char *name, size_t size,
 {
        struct kmem_cache *s;
 
+       BUG_ON(dtor);
        down_write(&slub_lock);
-       s = find_mergeable(size, align, flags, ctor, dtor);
+       s = find_mergeable(size, align, flags, ctor);
        if (s) {
                s->refcount++;
                /*
@@ -2536,7 +2531,7 @@ struct kmem_cache *kmem_cache_create(const char *name, size_t size,
        } else {
                s = kmalloc(kmem_size, GFP_KERNEL);
                if (s && kmem_cache_open(s, GFP_KERNEL, name,
-                               size, align, flags, ctor, dtor)) {
+                               size, align, flags, ctor)) {
                        if (sysfs_slab_add(s)) {
                                kfree(s);
                                goto err;
@@ -3177,17 +3172,6 @@ static ssize_t ctor_show(struct kmem_cache *s, char *buf)
 }
 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);
@@ -3419,7 +3403,6 @@ static struct attribute * slab_attrs[] = {
        &partial_attr.attr,
        &cpu_slabs_attr.attr,
        &ctor_attr.attr,
-       &dtor_attr.attr,
        &aliases_attr.attr,
        &align_attr.attr,
        &sanity_checks_attr.attr,