Dave Hansen 5509a5d27b drop_caches: add some documentation and info message ... There is plenty of anecdotal evidence and a load of blog posts suggesting that using "drop_caches" periodically keeps your system running in "tip top shape". Perhaps adding some kernel documentation will increase the amount of accurate data on its use. If we are not shrinking caches effectively, then we have real bugs. Using drop_caches will simply mask the bugs and make them harder to find, but certainly does not fix them, nor is it an appropriate "workaround" to limit the size of the caches. On the contrary, there have been bug reports on issues that turned out to be misguided use of cache dropping. Dropping caches is a very drastic and disruptive operation that is good for debugging and running tests, but if it creates bug reports from production use, kernel developers should be aware of its use. Add a bit more documentation about it, a syslog message to track down abusers, and vmstat drop counters to help analyze problem reports. [akpm@linux-foundation.org: checkpatch fixes] [hannes@cmpxchg.org: add runtime suppression control] Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com> Signed-off-by: Michal Hocko <mhocko@suse.cz> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2014-04-03 16:21:04 -07:00
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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.c: mark function as static	2014-04-03 16:21:02 -07:00
debug-pagealloc.c
dmapool.c
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
filemap.c	mm: remove read_cache_page_async()	2014-04-03 16:21:04 -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
huge_memory.c	mm, thp: drop do_huge_pmd_wp_zero_page_fallback()	2014-04-03 16:21:04 -07:00
hugetlb.c	mm, hugetlb: mark some bootstrap functions as __init	2014-04-03 16:21:01 -07:00
hugetlb_cgroup.c	mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE	2014-01-23 16:36:50 -08:00
hwpoison-inject.c	mm/hwpoison: add '#' to hwpoison_inject	2014-01-21 16:19:48 -08:00
init-mm.c
internal.h	mm/page-writeback.c: do not count anon pages as dirtyable memory	2014-01-29 16:22:39 -08:00
interval_tree.c
Kconfig	mm/Kconfig: fix URL for zsmalloc benchmark	2014-03-10 17:26:20 -07:00
Kconfig.debug
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
madvise.c	mm/hwpoison: fix traversal of hugetlbfs pages to avoid printk flood	2013-09-30 14:31:02 -07:00
Makefile	mm: thrash detection-based file cache sizing	2014-04-03 16:21:01 -07:00
memblock.c	memblock: add limit checking to memblock_virt_alloc	2014-01-29 16:22:40 -08:00
memcontrol.c	memcg: reparent charges of children before processing parent	2014-03-04 07:55:48 -08:00
memory-failure.c	mm: close PageTail race	2014-03-04 07:55:47 -08:00
memory.c	mm: consolidate code to setup pte	2014-04-03 16:21:04 -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: optimize put_mems_allowed() usage	2014-04-03 16:20:58 -07:00
mempool.c	mm/mempool.c: convert kmalloc_node(...GFP_ZERO...) to kzalloc_node(...)	2013-09-11 15:58:14 -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: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE	2014-01-23 16:36:50 -08:00
mm_init.c	mm: bring back /sys/kernel/mm	2014-01-27 21:02:39 -08:00
mmap.c	mm/mmap.c: mark function as static	2014-04-03 16:21:02 -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: Use ptep/pmdp_set_numa() for updating _PAGE_NUMA bit	2014-02-17 11:19:36 +11:00
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: add overcommit_kbytes sysctl variable	2014-01-21 16:19:44 -08:00
oom_kill.c	mm, oom: base root bonus on current usage	2014-01-30 16:56:56 -08:00
page-writeback.c	mm: __set_page_dirty_nobuffers() uses spin_lock_irqsave() instead of spin_lock_irq()	2014-02-06 13:48:51 -08:00
page_alloc.c	mm: optimize put_mems_allowed() usage	2014-04-03 16:20:58 -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
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
readahead.c	mm + fs: prepare for non-page entries in page cache radix trees	2014-04-03 16:21:00 -07:00
rmap.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux	2014-03-31 14:35:30 -07:00
shmem.c	mm + fs: prepare for non-page entries in page cache radix trees	2014-04-03 16:21:00 -07:00
slab.c	mm: optimize put_mems_allowed() usage	2014-04-03 16:20:58 -07:00
slab.h	memcg, slab: RCU protect memcg_params for root caches	2014-01-23 16:36:51 -08:00
slab_common.c	slab: fix wrong retval on kmem_cache_create_memcg error path	2014-01-29 16:22:40 -08:00
slob.c	mm/sl[aou]b: Move kmallocXXX functions to common code	2013-09-04 20:51:33 +03:00
slub.c	mm: optimize put_mems_allowed() usage	2014-04-03 16:20:58 -07:00
sparse-vmemmap.c	mm/sparse: use memblock apis for early memory allocations	2014-01-21 16:19:47 -08:00
sparse.c	sparse: fix comment	2014-04-02 09:16:17 +02:00
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: add overcommit_kbytes sysctl variable	2014-01-21 16:19:44 -08:00
vmalloc.c	Revert "mm/vmalloc: interchage the implementation of vmalloc_to_{pfn,page}"	2014-01-27 21:02:39 -08:00
vmpressure.c	arm, pm, vmpressure: add missing slab.h includes	2014-02-03 13:24:01 -05:00
vmscan.c	mm: thrash detection-based file cache sizing	2014-04-03 16:21:01 -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: change params from hidden to ro	2014-01-23 16:36:50 -08:00