2 files changed, 49 insertions, 159 deletions

diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h
index 1e14beb23f9b..17ebe0f89bf3 100644
--- a/include/linux/slub_def.h
+++ b/include/linux/slub_def.h
@@ -69,6 +69,7 @@ struct kmem_cache_order_objects {
  * Slab cache management.
  */
 struct kmem_cache {
+        struct kmem_cache_cpu *cpu_slab;
         /* Used for retriving partial slabs etc */
         unsigned long flags;
         int size;               /* The size of an object including meta data */
@@ -104,11 +105,6 @@ struct kmem_cache {
         int remote_node_defrag_ratio;
         struct kmem_cache_node *node[MAX_NUMNODES];
 #endif
-#ifdef CONFIG_SMP
-        struct kmem_cache_cpu *cpu_slab[NR_CPUS];
-#else
-        struct kmem_cache_cpu cpu_slab;
-#endif
 };
 
 /*
diff --git a/mm/slub.c b/mm/slub.c
index 8d71aaf888d7..d6c9ecf629d5 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -242,15 +242,6 @@ static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node)
 #endif
 }
 
-static inline struct kmem_cache_cpu *get_cpu_slab(struct kmem_cache *s, int cpu)
-{
-#ifdef CONFIG_SMP
-        return s->cpu_slab[cpu];
-#else
-        return &s->cpu_slab;
-#endif
-}
-
 /* Verify that a pointer has an address that is valid within a slab page */
 static inline int check_valid_pointer(struct kmem_cache *s,
                                 struct page *page, const void *object)
@@ -1124,7 +1115,7 @@ static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node)
                 if (!page)
                         return NULL;
 
-                stat(get_cpu_slab(s, raw_smp_processor_id()), ORDER_FALLBACK);
+                stat(this_cpu_ptr(s->cpu_slab), ORDER_FALLBACK);
         }
 
         if (kmemcheck_enabled
@@ -1422,7 +1413,7 @@ static struct page *get_partial(struct kmem_cache *s, gfp_t flags, int node)
 static void unfreeze_slab(struct kmem_cache *s, struct page *page, int tail)
 {
         struct kmem_cache_node *n = get_node(s, page_to_nid(page));
-        struct kmem_cache_cpu *c = get_cpu_slab(s, smp_processor_id());
+        struct kmem_cache_cpu *c = this_cpu_ptr(s->cpu_slab);
 
         __ClearPageSlubFrozen(page);
         if (page->inuse) {
@@ -1454,7 +1445,7 @@ static void unfreeze_slab(struct kmem_cache *s, struct page *page, int tail)
                         slab_unlock(page);
                 } else {
                         slab_unlock(page);
-                        stat(get_cpu_slab(s, raw_smp_processor_id()), FREE_SLAB);
+                        stat(__this_cpu_ptr(s->cpu_slab), FREE_SLAB);
                         discard_slab(s, page);
                 }
         }
@@ -1507,7 +1498,7 @@ static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c)
  */
 static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu)
 {
-        struct kmem_cache_cpu *c = get_cpu_slab(s, cpu);
+        struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu);
 
         if (likely(c && c->page))
                 flush_slab(s, c);
@@ -1673,7 +1664,7 @@ new_slab:
                 local_irq_disable();
 
         if (new) {
-                c = get_cpu_slab(s, smp_processor_id());
+                c = __this_cpu_ptr(s->cpu_slab);
                 stat(c, ALLOC_SLAB);
                 if (c->page)
                         flush_slab(s, c);
@@ -1711,7 +1702,7 @@ static __always_inline void *slab_alloc(struct kmem_cache *s,
         void **object;
         struct kmem_cache_cpu *c;
         unsigned long flags;
-        unsigned int objsize;
+        unsigned long objsize;
 
         gfpflags &= gfp_allowed_mask;
 
@@ -1722,14 +1713,14 @@ static __always_inline void *slab_alloc(struct kmem_cache *s,
                 return NULL;
 
         local_irq_save(flags);
-        c = get_cpu_slab(s, smp_processor_id());
+        c = __this_cpu_ptr(s->cpu_slab);
+        object = c->freelist;
         objsize = c->objsize;
-        if (unlikely(!c->freelist || !node_match(c, node)))
+        if (unlikely(!object || !node_match(c, node)))
 
                 object = __slab_alloc(s, gfpflags, node, addr, c);
 
         else {
-                object = c->freelist;
                 c->freelist = object[c->offset];
                 stat(c, ALLOC_FASTPATH);
         }
@@ -1800,7 +1791,7 @@ static void __slab_free(struct kmem_cache *s, struct page *page,
         void **object = (void *)x;
         struct kmem_cache_cpu *c;
 
-        c = get_cpu_slab(s, raw_smp_processor_id());
+        c = __this_cpu_ptr(s->cpu_slab);
         stat(c, FREE_SLOWPATH);
         slab_lock(page);
 
@@ -1872,7 +1863,7 @@ static __always_inline void slab_free(struct kmem_cache *s,
 
         kmemleak_free_recursive(x, s->flags);
         local_irq_save(flags);
-        c = get_cpu_slab(s, smp_processor_id());
+        c = __this_cpu_ptr(s->cpu_slab);
         kmemcheck_slab_free(s, object, c->objsize);
         debug_check_no_locks_freed(object, c->objsize);
         if (!(s->flags & SLAB_DEBUG_OBJECTS))
@@ -2095,130 +2086,28 @@ init_kmem_cache_node(struct kmem_cache_node *n, struct kmem_cache *s)
 #endif
 }
 
-#ifdef CONFIG_SMP
-/*
- * Per cpu array for per cpu structures.
- *
- * The per cpu array places all kmem_cache_cpu structures from one processor
- * close together meaning that it becomes possible that multiple per cpu
- * structures are contained in one cacheline. This may be particularly
- * beneficial for the kmalloc caches.
- *
- * A desktop system typically has around 60-80 slabs. With 100 here we are
- * likely able to get per cpu structures for all caches from the array defined
- * here. We must be able to cover all kmalloc caches during bootstrap.
- *
- * If the per cpu array is exhausted then fall back to kmalloc
- * of individual cachelines. No sharing is possible then.
- */
-#define NR_KMEM_CACHE_CPU 100
-
-static DEFINE_PER_CPU(struct kmem_cache_cpu [NR_KMEM_CACHE_CPU],
-                      kmem_cache_cpu);
-
-static DEFINE_PER_CPU(struct kmem_cache_cpu *, kmem_cache_cpu_free);
-static DECLARE_BITMAP(kmem_cach_cpu_free_init_once, CONFIG_NR_CPUS);
-
-static struct kmem_cache_cpu *alloc_kmem_cache_cpu(struct kmem_cache *s,
-                                                        int cpu, gfp_t flags)
-{
-        struct kmem_cache_cpu *c = per_cpu(kmem_cache_cpu_free, cpu);
-
-        if (c)
-                per_cpu(kmem_cache_cpu_free, cpu) =
-                                (void *)c->freelist;
-        else {
-                /* Table overflow: So allocate ourselves */
-                c = kmalloc_node(
-                        ALIGN(sizeof(struct kmem_cache_cpu), cache_line_size()),
-                        flags, cpu_to_node(cpu));
-                if (!c)
-                        return NULL;
-        }
-
-        init_kmem_cache_cpu(s, c);
-        return c;
-}
-
-static void free_kmem_cache_cpu(struct kmem_cache_cpu *c, int cpu)
-{
-        if (c < per_cpu(kmem_cache_cpu, cpu) ||
-                        c >= per_cpu(kmem_cache_cpu, cpu) + NR_KMEM_CACHE_CPU) {
-                kfree(c);
-                return;
-        }
-        c->freelist = (void *)per_cpu(kmem_cache_cpu_free, cpu);
-        per_cpu(kmem_cache_cpu_free, cpu) = c;
-}
-
-static void free_kmem_cache_cpus(struct kmem_cache *s)
-{
-        int cpu;
-
-        for_each_online_cpu(cpu) {
-                struct kmem_cache_cpu *c = get_cpu_slab(s, cpu);
-
-                if (c) {
-                        s->cpu_slab[cpu] = NULL;
-                        free_kmem_cache_cpu(c, cpu);
-                }
-        }
-}
-
-static int alloc_kmem_cache_cpus(struct kmem_cache *s, gfp_t flags)
-{
-        int cpu;
-
-        for_each_online_cpu(cpu) {
-                struct kmem_cache_cpu *c = get_cpu_slab(s, cpu);
+static DEFINE_PER_CPU(struct kmem_cache_cpu, kmalloc_percpu[SLUB_PAGE_SHIFT]);
 
-                if (c)
-                        continue;
-
-                c = alloc_kmem_cache_cpu(s, cpu, flags);
-                if (!c) {
-                        free_kmem_cache_cpus(s);
-                        return 0;
-                }
-                s->cpu_slab[cpu] = c;
-        }
-        return 1;
-}
-
-/*
- * Initialize the per cpu array.
- */
-static void init_alloc_cpu_cpu(int cpu)
-{
-        int i;
-
-        if (cpumask_test_cpu(cpu, to_cpumask(kmem_cach_cpu_free_init_once)))
-                return;
-
-        for (i = NR_KMEM_CACHE_CPU - 1; i >= 0; i--)
-                free_kmem_cache_cpu(&per_cpu(kmem_cache_cpu, cpu)[i], cpu);
-
-        cpumask_set_cpu(cpu, to_cpumask(kmem_cach_cpu_free_init_once));
-}
-
-static void __init init_alloc_cpu(void)
+static inline int alloc_kmem_cache_cpus(struct kmem_cache *s, gfp_t flags)
 {
         int cpu;
 
-        for_each_online_cpu(cpu)
-                init_alloc_cpu_cpu(cpu);
-  }
+        if (s < kmalloc_caches + SLUB_PAGE_SHIFT && s >= kmalloc_caches)
+                /*
+                 * Boot time creation of the kmalloc array. Use static per cpu data
+                 * since the per cpu allocator is not available yet.
+                 */
+                s->cpu_slab = per_cpu_var(kmalloc_percpu) + (s - kmalloc_caches);
+        else
+                s->cpu_slab =  alloc_percpu(struct kmem_cache_cpu);
 
-#else
-static inline void free_kmem_cache_cpus(struct kmem_cache *s) {}
-static inline void init_alloc_cpu(void) {}
+        if (!s->cpu_slab)
+                return 0;
 
-static inline int alloc_kmem_cache_cpus(struct kmem_cache *s, gfp_t flags)
-{
-        init_kmem_cache_cpu(s, &s->cpu_slab);
+        for_each_possible_cpu(cpu)
+                init_kmem_cache_cpu(s, per_cpu_ptr(s->cpu_slab, cpu));
         return 1;
 }
-#endif
 
 #ifdef CONFIG_NUMA
 /*
@@ -2609,9 +2498,8 @@ static inline int kmem_cache_close(struct kmem_cache *s)
         int node;
 
         flush_all(s);
-
+        free_percpu(s->cpu_slab);
         /* Attempt to free all objects */
-        free_kmem_cache_cpus(s);
         for_each_node_state(node, N_NORMAL_MEMORY) {
                 struct kmem_cache_node *n = get_node(s, node);
 
@@ -2760,7 +2648,19 @@ static noinline struct kmem_cache *dma_kmalloc_cache(int index, gfp_t flags)
         realsize = kmalloc_caches[index].objsize;
         text = kasprintf(flags & ~SLUB_DMA, "kmalloc_dma-%d",
                          (unsigned int)realsize);
-        s = kmalloc(kmem_size, flags & ~SLUB_DMA);
+
+        if (flags & __GFP_WAIT)
+                s = kmalloc(kmem_size, flags & ~SLUB_DMA);
+        else {
+                int i;
+
+                s = NULL;
+                for (i = 0; i < SLUB_PAGE_SHIFT; i++)
+                        if (kmalloc_caches[i].size) {
+                                s = kmalloc_caches + i;
+                                break;
+                        }
+        }
 
         /*
          * Must defer sysfs creation to a workqueue because we don't know
@@ -3176,8 +3076,6 @@ void __init kmem_cache_init(void)
         int i;
         int caches = 0;
 
-        init_alloc_cpu();
-
 #ifdef CONFIG_NUMA
         /*
          * Must first have the slab cache available for the allocations of the
@@ -3261,8 +3159,10 @@ void __init kmem_cache_init(void)
 
 #ifdef CONFIG_SMP
         register_cpu_notifier(&slab_notifier);
-        kmem_size = offsetof(struct kmem_cache, cpu_slab) +
-                                nr_cpu_ids * sizeof(struct kmem_cache_cpu *);
+#endif
+#ifdef CONFIG_NUMA
+        kmem_size = offsetof(struct kmem_cache, node) +
+                                nr_node_ids * sizeof(struct kmem_cache_node *);
 #else
         kmem_size = sizeof(struct kmem_cache);
 #endif
@@ -3365,7 +3265,7 @@ struct kmem_cache *kmem_cache_create(const char *name, size_t size,
                  * per cpu structures
                  */
                 for_each_online_cpu(cpu)
-                        get_cpu_slab(s, cpu)->objsize = s->objsize;
+                        per_cpu_ptr(s->cpu_slab, cpu)->objsize = s->objsize;
 
                 s->inuse = max_t(int, s->inuse, ALIGN(size, sizeof(void *)));
                 up_write(&slub_lock);
@@ -3422,11 +3322,9 @@ static int __cpuinit slab_cpuup_callback(struct notifier_block *nfb,
         switch (action) {
         case CPU_UP_PREPARE:
         case CPU_UP_PREPARE_FROZEN:
-                init_alloc_cpu_cpu(cpu);
                 down_read(&slub_lock);
                 list_for_each_entry(s, &slab_caches, list)
-                        s->cpu_slab[cpu] = alloc_kmem_cache_cpu(s, cpu,
-                                                        GFP_KERNEL);
+                        init_kmem_cache_cpu(s, per_cpu_ptr(s->cpu_slab, cpu));
                 up_read(&slub_lock);
                 break;
 
@@ -3436,13 +3334,9 @@ static int __cpuinit slab_cpuup_callback(struct notifier_block *nfb,
         case CPU_DEAD_FROZEN:
                 down_read(&slub_lock);
                 list_for_each_entry(s, &slab_caches, list) {
-                        struct kmem_cache_cpu *c = get_cpu_slab(s, cpu);
-
                         local_irq_save(flags);
                         __flush_cpu_slab(s, cpu);
                         local_irq_restore(flags);
-                        free_kmem_cache_cpu(c, cpu);
-                        s->cpu_slab[cpu] = NULL;
                 }
                 up_read(&slub_lock);
                 break;
@@ -3928,7 +3822,7 @@ static ssize_t show_slab_objects(struct kmem_cache *s,
                 int cpu;
 
                 for_each_possible_cpu(cpu) {
-                        struct kmem_cache_cpu *c = get_cpu_slab(s, cpu);
+                        struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu);
 
                         if (!c || c->node < 0)
                                 continue;
@@ -4353,7 +4247,7 @@ static int show_stat(struct kmem_cache *s, char *buf, enum stat_item si)
                 return -ENOMEM;
 
         for_each_online_cpu(cpu) {
-                unsigned x = get_cpu_slab(s, cpu)->stat[si];
+                unsigned x = per_cpu_ptr(s->cpu_slab, cpu)->stat[si];
 
                 data[cpu] = x;
                 sum += x;
@@ -4376,7 +4270,7 @@ static void clear_stat(struct kmem_cache *s, enum stat_item si)
         int cpu;
 
         for_each_online_cpu(cpu)
-                get_cpu_slab(s, cpu)->stat[si] = 0;
+                per_cpu_ptr(s->cpu_slab, cpu)->stat[si] = 0;
 }
 
 #define STAT_ATTR(si, text)                                     \