linux/mm
Vladimir Davydov a44cb94491 memcg, slab: never try to merge memcg caches
When a kmem cache is created (kmem_cache_create_memcg()), we first try to
find a compatible cache that already exists and can handle requests from
the new cache, i.e.  has the same object size, alignment, ctor, etc.  If
there is such a cache, we do not create any new caches, instead we simply
increment the refcount of the cache found and return it.

Currently we do this procedure not only when creating root caches, but
also for memcg caches.  However, there is no point in that, because, as
every memcg cache has exactly the same parameters as its parent and cache
merging cannot be turned off in runtime (only on boot by passing
"slub_nomerge"), the root caches of any two potentially mergeable memcg
caches should be merged already, i.e.  it must be the same root cache, and
therefore we couldn't even get to the memcg cache creation, because it
already exists.

The only exception is boot caches - they are explicitly forbidden to be
merged by setting their refcount to -1.  There are currently only two of
them - kmem_cache and kmem_cache_node, which are used in slab internals (I
do not count kmalloc caches as their refcount is set to 1 immediately
after creation).  Since they are prevented from merging preliminary I
guess we should avoid to merge their children too.

So let's remove the useless code responsible for merging memcg caches.

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Glauber Costa <glommer@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07 16:36:12 -07:00
..
backing-dev.c bdi: avoid oops on device removal 2014-04-03 16:20:49 -07:00
balloon_compaction.c mm: print more details for bad_page() 2014-01-23 16:36:50 -08:00
bootmem.c mm/bootmem.c: remove unused local `map' 2013-11-13 12:09:09 +09:00
bounce.c block: Convert bio_for_each_segment() to bvec_iter 2013-11-23 22:33:49 -08:00
cleancache.c mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE 2014-01-23 16:36:50 -08:00
compaction.c mm, compaction: determine isolation mode only once 2014-04-07 16:35:55 -07:00
debug-pagealloc.c mm, x86: Remove debug_pagealloc_enabled 2011-12-06 09:24:07 +01:00
dmapool.c dmapool: make DMAPOOL_DEBUG detect corruption of free marker 2012-12-11 17:22:24 -08:00
fadvise.c teach SYSCALL_DEFINE<n> how to deal with long long/unsigned long long 2013-03-03 22:46:22 -05:00
failslab.c switch debugfs to umode_t 2012-01-03 22:54:56 -05:00
filemap.c memcg: rename high level charging functions 2014-04-07 16:35:57 -07:00
filemap_xip.c seqcount: Add lockdep functionality to seqcount/seqlock structures 2013-11-06 12:40:26 +01:00
fremap.c mm: fix bad rss-counter if remap_file_pages raced migration 2014-03-19 16:21:49 -07:00
frontswap.c frontswap: fix incorrect zeroing and allocation size for frontswap_map 2013-06-12 16:29:46 -07:00
highmem.c Some nice cleanups, and even a patch my wife did as a "live" demo for 2012-12-20 08:37:05 -08:00
huge_memory.c memcg: rename high level charging functions 2014-04-07 16:35:57 -07:00
hugetlb.c mm: hugetlb: fix softlockup when a large number of hugepages are freed. 2014-04-07 16:35:58 -07:00
hugetlb_cgroup.c cgroup: drop const from @buffer of cftype->write_string() 2014-03-19 10:23:54 -04:00
hwpoison-inject.c mm/hwpoison: add '#' to hwpoison_inject 2014-01-21 16:19:48 -08:00
init-mm.c
internal.h mm/readahead.c: inline ra_submit 2014-04-07 16:35:58 -07:00
interval_tree.c mm: add CONFIG_DEBUG_VM_RB build option 2012-10-09 16:22:42 +09:00
Kconfig mm: disable split page table lock for !MMU 2014-04-07 16:35:52 -07:00
Kconfig.debug mm: more intensive memory corruption debugging 2012-01-10 16:30:42 -08:00
kmemcheck.c
kmemleak-test.c
kmemleak.c kmemleak: change some global variables to int 2014-04-03 16:20:50 -07:00
ksm.c mm: close PageTail race 2014-03-04 07:55:47 -08:00
list_lru.c mm: keep page cache radix tree nodes in check 2014-04-03 16:21:01 -07:00
maccess.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
madvise.c mm/hwpoison: fix traversal of hugetlbfs pages to avoid printk flood 2013-09-30 14:31:02 -07:00
Makefile mm: per-thread vma caching 2014-04-07 16:35:53 -07:00
memblock.c mm/memblock.c: use PFN_PHYS() 2014-04-07 16:35:58 -07:00
memcontrol.c memcg: rename high level charging functions 2014-04-07 16:35:57 -07:00
memory-failure.c Merge branch 'for-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup 2014-04-03 13:05:42 -07:00
memory.c mm: remove unused arg of set_page_dirty_balance() 2014-04-07 16:35:57 -07:00
memory_hotplug.c mm/memory_hotplug.c: move register_memory_resource out of the lock_memory_hotplug 2014-01-23 16:36:52 -08:00
mempolicy.c mm, mempolicy: remove per-process flag 2014-04-07 16:35:54 -07:00
mempool.c mempool: add unlikely and likely hints 2014-04-07 16:35:55 -07:00
migrate.c mm: fix swapops.h:131 bug if remap_file_pages raced migration 2014-03-20 22:09:09 -07:00
mincore.c mm + fs: prepare for non-page entries in page cache radix trees 2014-04-03 16:21:00 -07:00
mlock.c mm: try_to_unmap_cluster() should lock_page() before mlocking 2014-04-07 16:35:57 -07:00
mm_init.c mm: bring back /sys/kernel/mm 2014-01-27 21:02:39 -08:00
mmap.c mm: per-thread vma caching 2014-04-07 16:35:53 -07:00
mmu_context.c sched/mm: call finish_arch_post_lock_switch in idle_task_exit and use_mm 2014-02-21 08:50:17 +01:00
mmu_notifier.c mm: audit/fix non-modular users of module_init in core code 2014-01-23 16:36:52 -08:00
mmzone.c mm: numa: Change page last {nid,pid} into {cpu,pid} 2013-10-09 14:47:45 +02:00
mprotect.c mm: move mmu notifier call from change_protection to change_pmd_range 2014-04-07 16:35:50 -07:00
mremap.c mm: revert mremap pud_free anti-fix 2013-10-16 21:35:53 -07:00
msync.c
nobootmem.c mm/nobootmem.c: mark function as static 2014-04-03 16:21:02 -07:00
nommu.c mm: fix 'ERROR: do not initialise globals to 0 or NULL' and coding style 2014-04-07 16:35:55 -07:00
oom_kill.c mm, oom: base root bonus on current usage 2014-01-30 16:56:56 -08:00
page-writeback.c mm: remove unused arg of set_page_dirty_balance() 2014-04-07 16:35:57 -07:00
page_alloc.c mm/page_alloc.c: change mm debug routines back to EXPORT_SYMBOL 2014-04-07 16:35:59 -07:00
page_cgroup.c mm/page_cgroup.c: mark functions as static 2014-04-03 16:21:02 -07:00
page_io.c Merge branch 'for-3.14/core' of git://git.kernel.dk/linux-block 2014-01-30 11:19:05 -08:00
page_isolation.c mm: memory-hotplug: enable memory hotplug to handle hugepage 2013-09-11 15:57:48 -07:00
pagewalk.c mm/pagewalk.c: fix walk_page_range() access of wrong PTEs 2013-10-30 14:27:03 -07:00
percpu-km.c
percpu-vm.c mm: fix kernel-doc warnings 2012-06-20 14:39:36 -07:00
percpu.c percpu: renew the max_contig if we merge the head and previous block 2014-03-29 09:29:42 -04:00
pgtable-generic.c mm: fix TLB flush race between migration, and change_protection_range 2013-12-18 19:04:51 -08:00
process_vm_access.c mm/process_vm_access.c: mark function as static 2014-04-03 16:21:02 -07:00
quicklist.c mm: delete various needless include <linux/module.h> 2011-10-31 09:20:11 -04:00
readahead.c mm/readahead.c: inline ra_submit 2014-04-07 16:35:58 -07:00
rmap.c mm: try_to_unmap_cluster() should lock_page() before mlocking 2014-04-07 16:35:57 -07:00
shmem.c memcg: rename high level charging functions 2014-04-07 16:35:57 -07:00
slab.c mm, mempolicy: remove per-process flag 2014-04-07 16:35:54 -07:00
slab.h memcg, slab: never try to merge memcg caches 2014-04-07 16:36:12 -07:00
slab_common.c memcg, slab: never try to merge memcg caches 2014-04-07 16:36:12 -07:00
slob.c mm/sl[aou]b: Move kmallocXXX functions to common code 2013-09-04 20:51:33 +03:00
slub.c memcg, slab: never try to merge memcg caches 2014-04-07 16:36:12 -07:00
sparse-vmemmap.c mm/sparse: use memblock apis for early memory allocations 2014-01-21 16:19:47 -08:00
sparse.c mm: use macros from compiler.h instead of __attribute__((...)) 2014-04-07 16:35:54 -07:00
swap.c mm: thrash detection-based file cache sizing 2014-04-03 16:21:01 -07:00
swap_state.c swap: add a simple detector for inappropriate swapin readahead 2014-02-06 13:48:51 -08:00
swapfile.c mm/swap: fix race on swap_info reuse between swapoff and swapon 2014-02-06 13:48:51 -08:00
truncate.c mm: keep page cache radix tree nodes in check 2014-04-03 16:21:01 -07:00
util.c mm: use macros from compiler.h instead of __attribute__((...)) 2014-04-07 16:35:54 -07:00
vmacache.c mm: per-thread vma caching 2014-04-07 16:35:53 -07:00
vmalloc.c mm/vmalloc.c: enhance vm_map_ram() comment 2014-04-07 16:35:55 -07:00
vmpressure.c arm, pm, vmpressure: add missing slab.h includes 2014-02-03 13:24:01 -05:00
vmscan.c mm/vmscan: do not check compaction_ready on promoted zones 2014-04-07 16:35:50 -07:00
vmstat.c drop_caches: add some documentation and info message 2014-04-03 16:21:04 -07:00
workingset.c mm: keep page cache radix tree nodes in check 2014-04-03 16:21:01 -07:00
zbud.c mm/zbud: fix some trivial typos in comments 2013-09-11 15:57:35 -07:00
zsmalloc.c zsmalloc: add copyright 2014-01-30 16:56:55 -08:00
zswap.c mm/zswap.c: remove unnecessary parentheses 2014-04-07 16:36:03 -07:00