libata: implement drain buffers

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

diff --git a/mm/slub.c b/mm/slub.c
index e2989ae243b53571bb8ee5695771adbd90185f3d..4b3895cb90ee15b23ff7588e4b3079e405d8d8e1 100644 (file)
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -211,6 +211,8 @@ static inline void ClearSlabDebug(struct page *page)
 /* Internal SLUB flags */
 #define __OBJECT_POISON                0x80000000 /* Poison object */
 #define __SYSFS_ADD_DEFERRED   0x40000000 /* Not yet visible via sysfs */
+#define __KMALLOC_CACHE                0x20000000 /* objects freed using kfree */
+#define __PAGE_ALLOC_FALLBACK  0x10000000 /* Allow fallback to page alloc */
 
 /* Not all arches define cache_line_size */
 #ifndef cache_line_size
@@ -308,7 +310,7 @@ static inline int is_end(void *addr)
        return (unsigned long)addr & PAGE_MAPPING_ANON;
 }
 
-void *slab_address(struct page *page)
+static void *slab_address(struct page *page)
 {
        return page->end - PAGE_MAPPING_ANON;
 }
@@ -1078,14 +1080,7 @@ 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;
+       flags |= s->allocflags;
 
        if (node == -1)
                page = alloc_pages(flags, s->order);
@@ -1546,7 +1541,6 @@ load_freelist:
 unlock_out:
        slab_unlock(c->page);
        stat(c, ALLOC_SLOWPATH);
-out:
 #ifdef SLUB_FASTPATH
        local_irq_restore(flags);
 #endif
@@ -1581,8 +1575,24 @@ new_slab:
                c->page = new;
                goto load_freelist;
        }
-       object = NULL;
-       goto out;
+#ifdef SLUB_FASTPATH
+       local_irq_restore(flags);
+#endif
+       /*
+        * No memory available.
+        *
+        * If the slab uses higher order allocs but the object is
+        * smaller than a page size then we can fallback in emergencies
+        * to the page allocator via kmalloc_large. The page allocator may
+        * have failed to obtain a higher order page and we can try to
+        * allocate a single page if the object fits into a single page.
+        * That is only possible if certain conditions are met that are being
+        * checked when a slab is created.
+        */
+       if (!(gfpflags & __GFP_NORETRY) && (s->flags & __PAGE_ALLOC_FALLBACK))
+               return kmalloc_large(s->objsize, gfpflags);
+
+       return NULL;
 debug:
        object = c->page->freelist;
        if (!alloc_debug_processing(s, c->page, object, addr))
@@ -2329,10 +2339,33 @@ static int calculate_sizes(struct kmem_cache *s)
        size = ALIGN(size, align);
        s->size = size;
 
-       s->order = calculate_order(size);
+       if ((flags & __KMALLOC_CACHE) &&
+                       PAGE_SIZE / size < slub_min_objects) {
+               /*
+                * Kmalloc cache that would not have enough objects in
+                * an order 0 page. Kmalloc slabs can fallback to
+                * page allocator order 0 allocs so take a reasonably large
+                * order that will allows us a good number of objects.
+                */
+               s->order = max(slub_max_order, PAGE_ALLOC_COSTLY_ORDER);
+               s->flags |= __PAGE_ALLOC_FALLBACK;
+               s->allocflags |= __GFP_NOWARN;
+       } else
+               s->order = calculate_order(size);
+
        if (s->order < 0)
                return 0;
 
+       s->allocflags = 0;
+       if (s->order)
+               s->allocflags |= __GFP_COMP;
+
+       if (s->flags & SLAB_CACHE_DMA)
+               s->allocflags |= SLUB_DMA;
+
+       if (s->flags & SLAB_RECLAIM_ACCOUNT)
+               s->allocflags |= __GFP_RECLAIMABLE;
+
        /*
         * Determine the number of objects per slab
         */
@@ -2484,11 +2517,11 @@ EXPORT_SYMBOL(kmem_cache_destroy);
  *             Kmalloc subsystem
  *******************************************************************/
 
-struct kmem_cache kmalloc_caches[PAGE_SHIFT] __cacheline_aligned;
+struct kmem_cache kmalloc_caches[PAGE_SHIFT + 1] __cacheline_aligned;
 EXPORT_SYMBOL(kmalloc_caches);
 
 #ifdef CONFIG_ZONE_DMA
-static struct kmem_cache *kmalloc_caches_dma[PAGE_SHIFT];
+static struct kmem_cache *kmalloc_caches_dma[PAGE_SHIFT + 1];
 #endif
 
 static int __init setup_slub_min_order(char *str)
@@ -2536,7 +2569,7 @@ 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))
+                       flags | __KMALLOC_CACHE, NULL))
                goto panic;
 
        list_add(&s->list, &slab_caches);
@@ -2670,9 +2703,8 @@ void *__kmalloc(size_t size, gfp_t flags)
 {
        struct kmem_cache *s;
 
-       if (unlikely(size > PAGE_SIZE / 2))
-               return (void *)__get_free_pages(flags | __GFP_COMP,
-                                                       get_order(size));
+       if (unlikely(size > PAGE_SIZE))
+               return kmalloc_large(size, flags);
 
        s = get_slab(size, flags);
 
@@ -2688,9 +2720,8 @@ void *__kmalloc_node(size_t size, gfp_t flags, int node)
 {
        struct kmem_cache *s;
 
-       if (unlikely(size > PAGE_SIZE / 2))
-               return (void *)__get_free_pages(flags | __GFP_COMP,
-                                                       get_order(size));
+       if (unlikely(size > PAGE_SIZE))
+               return kmalloc_large(size, flags);
 
        s = get_slab(size, flags);
 
@@ -3001,7 +3032,7 @@ void __init kmem_cache_init(void)
                caches++;
        }
 
-       for (i = KMALLOC_SHIFT_LOW; i < PAGE_SHIFT; i++) {
+       for (i = KMALLOC_SHIFT_LOW; i <= PAGE_SHIFT; i++) {
                create_kmalloc_cache(&kmalloc_caches[i],
                        "kmalloc", 1 << i, GFP_KERNEL);
                caches++;
@@ -3028,7 +3059,7 @@ void __init kmem_cache_init(void)
        slab_state = UP;
 
        /* Provide the correct kmalloc names now that the caches are up */
-       for (i = KMALLOC_SHIFT_LOW; i < PAGE_SHIFT; i++)
+       for (i = KMALLOC_SHIFT_LOW; i <= PAGE_SHIFT; i++)
                kmalloc_caches[i]. name =
                        kasprintf(GFP_KERNEL, "kmalloc-%d", 1 << i);
 
@@ -3057,6 +3088,9 @@ static int slab_unmergeable(struct kmem_cache *s)
        if (slub_nomerge || (s->flags & SLUB_NEVER_MERGE))
                return 1;
 
+       if ((s->flags & __PAGE_ALLOC_FALLBACK))
+               return 1;
+
        if (s->ctor)
                return 1;
 
@@ -3218,9 +3252,9 @@ void *__kmalloc_track_caller(size_t size, gfp_t gfpflags, void *caller)
 {
        struct kmem_cache *s;
 
-       if (unlikely(size > PAGE_SIZE / 2))
-               return (void *)__get_free_pages(gfpflags | __GFP_COMP,
-                                                       get_order(size));
+       if (unlikely(size > PAGE_SIZE))
+               return kmalloc_large(size, gfpflags);
+
        s = get_slab(size, gfpflags);
 
        if (unlikely(ZERO_OR_NULL_PTR(s)))
@@ -3234,9 +3268,9 @@ void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags,
 {
        struct kmem_cache *s;
 
-       if (unlikely(size > PAGE_SIZE / 2))
-               return (void *)__get_free_pages(gfpflags | __GFP_COMP,
-                                                       get_order(size));
+       if (unlikely(size > PAGE_SIZE))
+               return kmalloc_large(size, gfpflags);
+
        s = get_slab(size, gfpflags);
 
        if (unlikely(ZERO_OR_NULL_PTR(s)))