diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-kernel-slab | 479 | ||||
| -rw-r--r-- | mm/slub.c | 3 |
2 files changed, 481 insertions, 1 deletions
diff --git a/Documentation/ABI/testing/sysfs-kernel-slab b/Documentation/ABI/testing/sysfs-kernel-slab new file mode 100644 index 00000000000..6dcf75e594f --- /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 aa34913a41e..65ffda5934b 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -1912,7 +1912,7 @@ static inline int calculate_order(int size) * 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 @@ __setup("slub_min_order=", setup_slub_min_order); 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; } |