Merge branch 'slab/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux

Pull slab update from Pekka Enberg:
 "Highlights:

  - Fix for boot-time problems on some architectures due to
    init_lock_keys() not respecting kmalloc_caches boundaries
    (Christoph Lameter)

  - CONFIG_SLUB_CPU_PARTIAL requested by RT folks (Joonsoo Kim)

  - Fix for excessive slab freelist draining (Wanpeng Li)

  - SLUB and SLOB cleanups and fixes (various people)"

I ended up editing the branch, and this avoids two commits at the end
that were immediately reverted, and I instead just applied the oneliner
fix in between myself.

* 'slab/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux
  slub: Check for page NULL before doing the node_match check
  mm/slab: Give s_next and s_stop slab-specific names
  slob: Check for NULL pointer before calling ctor()
  slub: Make cpu partial slab support configurable
  slab: add kmalloc() to kernel API documentation
  slab: fix init_lock_keys
  slob: use DIV_ROUND_UP where possible
  slub: do not put a slab to cpu partial list when cpu_partial is 0
  mm/slub: Use node_nr_slabs and node_nr_objs in get_slabinfo
  mm/slub: Drop unnecessary nr_partials
  mm/slab: Fix /proc/slabinfo unwriteable for slab
  mm/slab: Sharing s_next and s_stop between slab and slub
  mm/slab: Fix drain freelist excessively
  slob: Rework #ifdeffery in slab.h
  mm, slab: moved kmem_cache_alloc_node comment to correct place

1 files changed, 27 insertions, 11 deletions

diff --git a/mm/slub.c b/mm/slub.c
index 57707f01bcfb..3b482c863002 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -123,6 +123,15 @@ static inline int kmem_cache_debug(struct kmem_cache *s)
 #endif
 }
 
+static inline bool kmem_cache_has_cpu_partial(struct kmem_cache *s)
+{
+#ifdef CONFIG_SLUB_CPU_PARTIAL
+        return !kmem_cache_debug(s);
+#else
+        return false;
+#endif
+}
+
 /*
  * Issues still to be resolved:
  *
@@ -1573,7 +1582,8 @@ static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n,
                         put_cpu_partial(s, page, 0);
                         stat(s, CPU_PARTIAL_NODE);
                 }
-                if (kmem_cache_debug(s) || available > s->cpu_partial / 2)
+                if (!kmem_cache_has_cpu_partial(s)
+                        || available > s->cpu_partial / 2)
                         break;
 
         }
@@ -1884,6 +1894,7 @@ redo:
 static void unfreeze_partials(struct kmem_cache *s,
                 struct kmem_cache_cpu *c)
 {
+#ifdef CONFIG_SLUB_CPU_PARTIAL
         struct kmem_cache_node *n = NULL, *n2 = NULL;
         struct page *page, *discard_page = NULL;
 
@@ -1938,6 +1949,7 @@ static void unfreeze_partials(struct kmem_cache *s,
                 discard_slab(s, page);
                 stat(s, FREE_SLAB);
         }
+#endif
 }
 
 /*
@@ -1951,10 +1963,14 @@ static void unfreeze_partials(struct kmem_cache *s,
  */
 static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain)
 {
+#ifdef CONFIG_SLUB_CPU_PARTIAL
         struct page *oldpage;
         int pages;
         int pobjects;
 
+        if (!s->cpu_partial)
+                return;
+
         do {
                 pages = 0;
                 pobjects = 0;
@@ -1987,6 +2003,7 @@ static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain)
                 page->next = oldpage;
 
         } while (this_cpu_cmpxchg(s->cpu_slab->partial, oldpage, page) != oldpage);
+#endif
 }
 
 static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c)
@@ -2358,7 +2375,7 @@ redo:
 
         object = c->freelist;
         page = c->page;
-        if (unlikely(!object || !node_match(page, node)))
+        if (unlikely(!object || !page || !node_match(page, node)))
                 object = __slab_alloc(s, gfpflags, node, addr, c);
 
         else {
@@ -2495,7 +2512,7 @@ static void __slab_free(struct kmem_cache *s, struct page *page,
                 new.inuse--;
                 if ((!new.inuse || !prior) && !was_frozen) {
 
-                        if (!kmem_cache_debug(s) && !prior)
+                        if (kmem_cache_has_cpu_partial(s) && !prior)
 
                                 /*
                                  * Slab was on no list before and will be partially empty
@@ -2550,8 +2567,9 @@ static void __slab_free(struct kmem_cache *s, struct page *page,
          * Objects left in the slab. If it was not on the partial list before
          * then add it.
          */
-        if (kmem_cache_debug(s) && unlikely(!prior)) {
-                remove_full(s, page);
+        if (!kmem_cache_has_cpu_partial(s) && unlikely(!prior)) {
+                if (kmem_cache_debug(s))
+                        remove_full(s, page);
                 add_partial(n, page, DEACTIVATE_TO_TAIL);
                 stat(s, FREE_ADD_PARTIAL);
         }
@@ -3059,7 +3077,7 @@ static int kmem_cache_open(struct kmem_cache *s, unsigned long flags)
          *    per node list when we run out of per cpu objects. We only fetch 50%
          *    to keep some capacity around for frees.
          */
-        if (kmem_cache_debug(s))
+        if (!kmem_cache_has_cpu_partial(s))
                 s->cpu_partial = 0;
         else if (s->size >= PAGE_SIZE)
                 s->cpu_partial = 2;
@@ -4456,7 +4474,7 @@ static ssize_t cpu_partial_store(struct kmem_cache *s, const char *buf,
         err = strict_strtoul(buf, 10, &objects);
         if (err)
                 return err;
-        if (objects && kmem_cache_debug(s))
+        if (objects && !kmem_cache_has_cpu_partial(s))
                 return -EINVAL;
 
         s->cpu_partial = objects;
@@ -5269,7 +5287,6 @@ __initcall(slab_sysfs_init);
 #ifdef CONFIG_SLABINFO
 void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo)
 {
-        unsigned long nr_partials = 0;
         unsigned long nr_slabs = 0;
         unsigned long nr_objs = 0;
         unsigned long nr_free = 0;
@@ -5281,9 +5298,8 @@ void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo)
                 if (!n)
                         continue;
 
-                nr_partials += n->nr_partial;
-                nr_slabs += atomic_long_read(&n->nr_slabs);
-                nr_objs += atomic_long_read(&n->total_objects);
+                nr_slabs += node_nr_slabs(n);
+                nr_objs += node_nr_objs(n);
                 nr_free += count_partial(n, count_free);
         }