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

2 files changed, 42 insertions, 23 deletions

diff --git a/include/linux/slab.h b/include/linux/slab.h
index 0c621752caa6..6c5cc0ea8713 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -169,11 +169,7 @@ struct kmem_cache {
         struct list_head list;  /* List of all slab caches on the system */
 };
 
-#define KMALLOC_MAX_SIZE (1UL << 30)
-
-#include <linux/slob_def.h>
-
-#else /* CONFIG_SLOB */
+#endif /* CONFIG_SLOB */
 
 /*
  * Kmalloc array related definitions
@@ -195,7 +191,9 @@ struct kmem_cache {
 #ifndef KMALLOC_SHIFT_LOW
 #define KMALLOC_SHIFT_LOW       5
 #endif
-#else
+#endif
+
+#ifdef CONFIG_SLUB
 /*
  * SLUB allocates up to order 2 pages directly and otherwise
  * passes the request to the page allocator.
@@ -207,6 +205,19 @@ struct kmem_cache {
 #endif
 #endif
 
+#ifdef CONFIG_SLOB
+/*
+ * SLOB passes all page size and larger requests to the page allocator.
+ * No kmalloc array is necessary since objects of different sizes can
+ * be allocated from the same page.
+ */
+#define KMALLOC_SHIFT_MAX       30
+#define KMALLOC_SHIFT_HIGH      PAGE_SHIFT
+#ifndef KMALLOC_SHIFT_LOW
+#define KMALLOC_SHIFT_LOW       3
+#endif
+#endif
+
 /* Maximum allocatable size */
 #define KMALLOC_MAX_SIZE        (1UL << KMALLOC_SHIFT_MAX)
 /* Maximum size for which we actually use a slab cache */
@@ -221,6 +232,7 @@ struct kmem_cache {
 #define KMALLOC_MIN_SIZE (1 << KMALLOC_SHIFT_LOW)
 #endif
 
+#ifndef CONFIG_SLOB
 extern struct kmem_cache *kmalloc_caches[KMALLOC_SHIFT_HIGH + 1];
 #ifdef CONFIG_ZONE_DMA
 extern struct kmem_cache *kmalloc_dma_caches[KMALLOC_SHIFT_HIGH + 1];
@@ -275,13 +287,18 @@ static __always_inline int kmalloc_index(size_t size)
         /* Will never be reached. Needed because the compiler may complain */
         return -1;
 }
+#endif /* !CONFIG_SLOB */
 
 #ifdef CONFIG_SLAB
 #include <linux/slab_def.h>
-#elif defined(CONFIG_SLUB)
+#endif
+
+#ifdef CONFIG_SLUB
 #include <linux/slub_def.h>
-#else
-#error "Unknown slab allocator"
+#endif
+
+#ifdef CONFIG_SLOB
+#include <linux/slob_def.h>
 #endif
 
 /*
@@ -291,6 +308,7 @@ static __always_inline int kmalloc_index(size_t size)
  */
 static __always_inline int kmalloc_size(int n)
 {
+#ifndef CONFIG_SLOB
         if (n > 2)
                 return 1 << n;
 
@@ -299,10 +317,9 @@ static __always_inline int kmalloc_size(int n)
 
         if (n == 2 && KMALLOC_MIN_SIZE <= 64)
                 return 192;
-
+#endif
         return 0;
 }
-#endif /* !CONFIG_SLOB */
 
 /*
  * Setting ARCH_SLAB_MINALIGN in arch headers allows a different alignment.
@@ -356,9 +373,8 @@ int cache_show(struct kmem_cache *s, struct seq_file *m);
 void print_slabinfo_header(struct seq_file *m);
 
 /**
- * kmalloc_array - allocate memory for an array.
- * @n: number of elements.
- * @size: element size.
+ * kmalloc - allocate memory
+ * @size: how many bytes of memory are required.
  * @flags: the type of memory to allocate.
  *
  * The @flags argument may be one of:
@@ -405,6 +421,17 @@ void print_slabinfo_header(struct seq_file *m);
  * There are other flags available as well, but these are not intended
  * for general use, and so are not documented here. For a full list of
  * potential flags, always refer to linux/gfp.h.
+ *
+ * kmalloc is the normal method of allocating memory
+ * in the kernel.
+ */
+static __always_inline void *kmalloc(size_t size, gfp_t flags);
+
+/**
+ * kmalloc_array - allocate memory for an array.
+ * @n: number of elements.
+ * @size: element size.
+ * @flags: the type of memory to allocate (see kmalloc).
  */
 static inline void *kmalloc_array(size_t n, size_t size, gfp_t flags)
 {
@@ -428,7 +455,7 @@ static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
 /**
  * kmalloc_node - allocate memory from a specific node
  * @size: how many bytes of memory are required.
- * @flags: the type of memory to allocate (see kcalloc).
+ * @flags: the type of memory to allocate (see kmalloc).
  * @node: node to allocate from.
  *
  * kmalloc() for non-local nodes, used to allocate from a specific node
diff --git a/include/linux/slob_def.h b/include/linux/slob_def.h
index f28e14a12e3f..095a5a4a8516 100644
--- a/include/linux/slob_def.h
+++ b/include/linux/slob_def.h
@@ -18,14 +18,6 @@ static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
         return __kmalloc_node(size, flags, node);
 }
 
-/**
- * kmalloc - allocate memory
- * @size: how many bytes of memory are required.
- * @flags: the type of memory to allocate (see kcalloc).
- *
- * kmalloc is the normal method of allocating memory
- * in the kernel.
- */
 static __always_inline void *kmalloc(size_t size, gfp_t flags)
 {
         return __kmalloc_node(size, flags, NUMA_NO_NODE);