Merge branches 'topic/documentation', 'topic/slub/fixes' and 'topic/urgent' into for-linus
diff --git a/Documentation/ABI/testing/sysfs-kernel-slab b/Documentation/ABI/testing/sysfs-kernel-slab
new file mode 100644
index 0000000..6dcf75e
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-kernel-slab
@@ -0,0 +1,479 @@
+What: /sys/kernel/slab
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The /sys/kernel/slab directory contains a snapshot of the
+ internal state of the SLUB allocator for each cache. Certain
+ files may be modified to change the behavior of the cache (and
+ any cache it aliases, if any).
+Users: kernel memory tuning tools
+
+What: /sys/kernel/slab/cache/aliases
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The aliases file is read-only and specifies how many caches
+ have merged into this cache.
+
+What: /sys/kernel/slab/cache/align
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The align file is read-only and specifies the cache's object
+ alignment in bytes.
+
+What: /sys/kernel/slab/cache/alloc_calls
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The alloc_calls file is read-only and lists the kernel code
+ locations from which allocations for this cache were performed.
+ The alloc_calls file only contains information if debugging is
+ enabled for that cache (see Documentation/vm/slub.txt).
+
+What: /sys/kernel/slab/cache/alloc_fastpath
+Date: February 2008
+KernelVersion: 2.6.25
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The alloc_fastpath file is read-only and specifies how many
+ objects have been allocated using the fast path.
+ Available when CONFIG_SLUB_STATS is enabled.
+
+What: /sys/kernel/slab/cache/alloc_from_partial
+Date: February 2008
+KernelVersion: 2.6.25
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The alloc_from_partial file is read-only and specifies how
+ many times a cpu slab has been full and it has been refilled
+ by using a slab from the list of partially used slabs.
+ Available when CONFIG_SLUB_STATS is enabled.
+
+What: /sys/kernel/slab/cache/alloc_refill
+Date: February 2008
+KernelVersion: 2.6.25
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The alloc_refill file is read-only and specifies how many
+ times the per-cpu freelist was empty but there were objects
+ available as the result of remote cpu frees.
+ Available when CONFIG_SLUB_STATS is enabled.
+
+What: /sys/kernel/slab/cache/alloc_slab
+Date: February 2008
+KernelVersion: 2.6.25
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The alloc_slab file is read-only and specifies how many times
+ a new slab had to be allocated from the page allocator.
+ Available when CONFIG_SLUB_STATS is enabled.
+
+What: /sys/kernel/slab/cache/alloc_slowpath
+Date: February 2008
+KernelVersion: 2.6.25
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The alloc_slowpath file is read-only and specifies how many
+ objects have been allocated using the slow path because of a
+ refill or allocation from a partial or new slab.
+ Available when CONFIG_SLUB_STATS is enabled.
+
+What: /sys/kernel/slab/cache/cache_dma
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The cache_dma file is read-only and specifies whether objects
+ are from ZONE_DMA.
+ Available when CONFIG_ZONE_DMA is enabled.
+
+What: /sys/kernel/slab/cache/cpu_slabs
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The cpu_slabs file is read-only and displays how many cpu slabs
+ are active and their NUMA locality.
+
+What: /sys/kernel/slab/cache/cpuslab_flush
+Date: April 2009
+KernelVersion: 2.6.31
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The file cpuslab_flush is read-only and specifies how many
+ times a cache's cpu slabs have been flushed as the result of
+ destroying or shrinking a cache, a cpu going offline, or as
+ the result of forcing an allocation from a certain node.
+ Available when CONFIG_SLUB_STATS is enabled.
+
+What: /sys/kernel/slab/cache/ctor
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The ctor file is read-only and specifies the cache's object
+ constructor function, which is invoked for each object when a
+ new slab is allocated.
+
+What: /sys/kernel/slab/cache/deactivate_empty
+Date: February 2008
+KernelVersion: 2.6.25
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The file deactivate_empty is read-only and specifies how many
+ times an empty cpu slab was deactivated.
+ Available when CONFIG_SLUB_STATS is enabled.
+
+What: /sys/kernel/slab/cache/deactivate_full
+Date: February 2008
+KernelVersion: 2.6.25
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The file deactivate_full is read-only and specifies how many
+ times a full cpu slab was deactivated.
+ Available when CONFIG_SLUB_STATS is enabled.
+
+What: /sys/kernel/slab/cache/deactivate_remote_frees
+Date: February 2008
+KernelVersion: 2.6.25
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The file deactivate_remote_frees is read-only and specifies how
+ many times a cpu slab has been deactivated and contained free
+ objects that were freed remotely.
+ Available when CONFIG_SLUB_STATS is enabled.
+
+What: /sys/kernel/slab/cache/deactivate_to_head
+Date: February 2008
+KernelVersion: 2.6.25
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The file deactivate_to_head is read-only and specifies how
+ many times a partial cpu slab was deactivated and added to the
+ head of its node's partial list.
+ Available when CONFIG_SLUB_STATS is enabled.
+
+What: /sys/kernel/slab/cache/deactivate_to_tail
+Date: February 2008
+KernelVersion: 2.6.25
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The file deactivate_to_tail is read-only and specifies how
+ many times a partial cpu slab was deactivated and added to the
+ tail of its node's partial list.
+ Available when CONFIG_SLUB_STATS is enabled.
+
+What: /sys/kernel/slab/cache/destroy_by_rcu
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The destroy_by_rcu file is read-only and specifies whether
+ slabs (not objects) are freed by rcu.
+
+What: /sys/kernel/slab/cache/free_add_partial
+Date: February 2008
+KernelVersion: 2.6.25
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The file free_add_partial is read-only and specifies how many
+ times an object has been freed in a full slab so that it had to
+ added to its node's partial list.
+ Available when CONFIG_SLUB_STATS is enabled.
+
+What: /sys/kernel/slab/cache/free_calls
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The free_calls file is read-only and lists the locations of
+ object frees if slab debugging is enabled (see
+ Documentation/vm/slub.txt).
+
+What: /sys/kernel/slab/cache/free_fastpath
+Date: February 2008
+KernelVersion: 2.6.25
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The free_fastpath file is read-only and specifies how many
+ objects have been freed using the fast path because it was an
+ object from the cpu slab.
+ Available when CONFIG_SLUB_STATS is enabled.
+
+What: /sys/kernel/slab/cache/free_frozen
+Date: February 2008
+KernelVersion: 2.6.25
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The free_frozen file is read-only and specifies how many
+ objects have been freed to a frozen slab (i.e. a remote cpu
+ slab).
+ Available when CONFIG_SLUB_STATS is enabled.
+
+What: /sys/kernel/slab/cache/free_remove_partial
+Date: February 2008
+KernelVersion: 2.6.25
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The file free_remove_partial is read-only and specifies how
+ many times an object has been freed to a now-empty slab so
+ that it had to be removed from its node's partial list.
+ Available when CONFIG_SLUB_STATS is enabled.
+
+What: /sys/kernel/slab/cache/free_slab
+Date: February 2008
+KernelVersion: 2.6.25
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The free_slab file is read-only and specifies how many times an
+ empty slab has been freed back to the page allocator.
+ Available when CONFIG_SLUB_STATS is enabled.
+
+What: /sys/kernel/slab/cache/free_slowpath
+Date: February 2008
+KernelVersion: 2.6.25
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The free_slowpath file is read-only and specifies how many
+ objects have been freed using the slow path (i.e. to a full or
+ partial slab).
+ Available when CONFIG_SLUB_STATS is enabled.
+
+What: /sys/kernel/slab/cache/hwcache_align
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The hwcache_align file is read-only and specifies whether
+ objects are aligned on cachelines.
+
+What: /sys/kernel/slab/cache/min_partial
+Date: February 2009
+KernelVersion: 2.6.30
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ David Rientjes <rientjes@google.com>
+Description:
+ The min_partial file specifies how many empty slabs shall
+ remain on a node's partial list to avoid the overhead of
+ allocating new slabs. Such slabs may be reclaimed by utilizing
+ the shrink file.
+
+What: /sys/kernel/slab/cache/object_size
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The object_size file is read-only and specifies the cache's
+ object size.
+
+What: /sys/kernel/slab/cache/objects
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The objects file is read-only and displays how many objects are
+ active and from which nodes they are from.
+
+What: /sys/kernel/slab/cache/objects_partial
+Date: April 2008
+KernelVersion: 2.6.26
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The objects_partial file is read-only and displays how many
+ objects are on partial slabs and from which nodes they are
+ from.
+
+What: /sys/kernel/slab/cache/objs_per_slab
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The file objs_per_slab is read-only and specifies how many
+ objects may be allocated from a single slab of the order
+ specified in /sys/kernel/slab/cache/order.
+
+What: /sys/kernel/slab/cache/order
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The order file specifies the page order at which new slabs are
+ allocated. It is writable and can be changed to increase the
+ number of objects per slab. If a slab cannot be allocated
+ because of fragmentation, SLUB will retry with the minimum order
+ possible depending on its characteristics.
+
+What: /sys/kernel/slab/cache/order_fallback
+Date: April 2008
+KernelVersion: 2.6.26
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The file order_fallback is read-only and specifies how many
+ times an allocation of a new slab has not been possible at the
+ cache's order and instead fallen back to its minimum possible
+ order.
+ Available when CONFIG_SLUB_STATS is enabled.
+
+What: /sys/kernel/slab/cache/partial
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The partial file is read-only and displays how long many
+ partial slabs there are and how long each node's list is.
+
+What: /sys/kernel/slab/cache/poison
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The poison file specifies whether objects should be poisoned
+ when a new slab is allocated.
+
+What: /sys/kernel/slab/cache/reclaim_account
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The reclaim_account file specifies whether the cache's objects
+ are reclaimable (and grouped by their mobility).
+
+What: /sys/kernel/slab/cache/red_zone
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The red_zone file specifies whether the cache's objects are red
+ zoned.
+
+What: /sys/kernel/slab/cache/remote_node_defrag_ratio
+Date: January 2008
+KernelVersion: 2.6.25
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The file remote_node_defrag_ratio specifies the percentage of
+ times SLUB will attempt to refill the cpu slab with a partial
+ slab from a remote node as opposed to allocating a new slab on
+ the local node. This reduces the amount of wasted memory over
+ the entire system but can be expensive.
+ Available when CONFIG_NUMA is enabled.
+
+What: /sys/kernel/slab/cache/sanity_checks
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The sanity_checks file specifies whether expensive checks
+ should be performed on free and, at minimum, enables double free
+ checks. Caches that enable sanity_checks cannot be merged with
+ caches that do not.
+
+What: /sys/kernel/slab/cache/shrink
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The shrink file is written when memory should be reclaimed from
+ a cache. Empty partial slabs are freed and the partial list is
+ sorted so the slabs with the fewest available objects are used
+ first.
+
+What: /sys/kernel/slab/cache/slab_size
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The slab_size file is read-only and specifies the object size
+ with metadata (debugging information and alignment) in bytes.
+
+What: /sys/kernel/slab/cache/slabs
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The slabs file is read-only and displays how long many slabs
+ there are (both cpu and partial) and from which nodes they are
+ from.
+
+What: /sys/kernel/slab/cache/store_user
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The store_user file specifies whether the location of
+ allocation or free should be tracked for a cache.
+
+What: /sys/kernel/slab/cache/total_objects
+Date: April 2008
+KernelVersion: 2.6.26
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The total_objects file is read-only and displays how many total
+ objects a cache has and from which nodes they are from.
+
+What: /sys/kernel/slab/cache/trace
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ The trace file specifies whether object allocations and frees
+ should be traced.
+
+What: /sys/kernel/slab/cache/validate
+Date: May 2007
+KernelVersion: 2.6.22
+Contact: Pekka Enberg <penberg@cs.helsinki.fi>,
+ Christoph Lameter <cl@linux-foundation.org>
+Description:
+ Writing to the validate file causes SLUB to traverse all of its
+ cache's objects and check the validity of metadata.
diff --git a/mm/slub.c b/mm/slub.c
index aa34913..65ffda5 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1912,7 +1912,7 @@
* Doh this slab cannot be placed using slub_max_order.
*/
order = slab_order(size, 1, MAX_ORDER, 1);
- if (order <= MAX_ORDER)
+ if (order < MAX_ORDER)
return order;
return -ENOSYS;
}
@@ -2525,6 +2525,7 @@
static int __init setup_slub_max_order(char *str)
{
get_option(&str, &slub_max_order);
+ slub_max_order = min(slub_max_order, MAX_ORDER - 1);
return 1;
}