kernel_optimize_test/mm
Minchan Kim 52f37629fd THP: fix comment about memory barrier
Currently the memory barrier in __do_huge_pmd_anonymous_page doesn't
work.  Because lru_cache_add_lru uses pagevec so it could miss spinlock
easily so above rule was broken so user might see inconsistent data.

I was not first person who pointed out the problem.  Mel and Peter
pointed out a few months ago and Peter pointed out further that even
spin_lock/unlock can't make sure of it:

  http://marc.info/?t=134333512700004

	In particular:

        	*A = a;
        	LOCK
        	UNLOCK
        	*B = b;

	may occur as:

        	LOCK, STORE *B, STORE *A, UNLOCK

At last, Hugh pointed out that even we don't need memory barrier in
there because __SetPageUpdate already have done it from Nick's commit
0ed361dec3 ("mm: fix PageUptodate data race") explicitly.

So this patch fixes comment on THP and adds same comment for
do_anonymous_page, too because everybody except Hugh was missing that.
It means we need a comment about that.

Signed-off-by: Minchan Kim <minchan@kernel.org>
Acked-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 15:54:37 -07:00
..
backing-dev.c bdi: allow block devices to say that they require stable page writes 2013-02-21 17:22:19 -08:00
balloon_compaction.c mm: introduce a common interface for balloon pages mobility 2012-12-11 17:22:26 -08:00
bootmem.c mm: Add alloc_bootmem_low_pages_nopanic() 2013-01-29 19:32:59 -08:00
bounce.c mm: make snapshotting pages for stable writes a per-bio operation 2013-04-29 15:54:33 -07:00
cleancache.c fs: encode_fh: return FILEID_INVALID if invalid fid_type 2013-02-26 02:46:10 -05:00
compaction.c mm: add & use zone_end_pfn() and zone_spans_pfn() 2013-02-23 17:50:20 -08:00
debug-pagealloc.c
dmapool.c dmapool: make DMAPOOL_DEBUG detect corruption of free marker 2012-12-11 17:22:24 -08:00
fadvise.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-02-26 20:16:07 -08:00
failslab.c
filemap_xip.c mm: move all mmu notifier invocations to be done outside the PT lock 2012-10-09 16:22:58 +09:00
filemap.c mm: trace filemap add and del 2013-04-29 15:54:28 -07:00
fremap.c Revert "mm: introduce VM_POPULATE flag to better deal with racy userspace programs" 2013-03-28 17:45:51 -07:00
frontswap.c frontswap: support exclusive gets if tmem backend is capable 2012-09-21 10:38:12 -04:00
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 THP: fix comment about memory barrier 2013-04-29 15:54:37 -07:00
hugetlb_cgroup.c mm/hugetlb: create hugetlb cgroup file in hugetlb_init 2012-12-18 15:02:15 -08:00
hugetlb.c mm, hugetlb: include hugepages in meminfo 2013-04-29 15:54:35 -07:00
hwpoison-inject.c memcg: rename config variables 2012-07-31 18:42:43 -07:00
init-mm.c
internal.h mm: accelerate munlock() treatment of THP pages 2013-02-27 19:10:09 -08:00
interval_tree.c mm: add CONFIG_DEBUG_VM_RB build option 2012-10-09 16:22:42 +09:00
Kconfig Select VIRT_TO_BUS directly where needed 2013-03-12 11:16:40 -07:00
Kconfig.debug
kmemcheck.c
kmemleak-test.c
kmemleak.c hlist: drop the node parameter from iterators 2013-02-27 19:10:24 -08:00
ksm.c ksm: fix m68k build: only NUMA needs pfn_to_nid 2013-03-08 15:05:34 -08:00
maccess.c
madvise.c mm: make madvise(MADV_WILLNEED) support swap file prefetch 2013-02-23 17:50:10 -08:00
Makefile mm: introduce a common interface for balloon pages mobility 2012-12-11 17:22:26 -08:00
memblock.c memblock: add assertion for zero allocation alignment 2013-04-29 15:54:28 -07:00
memcontrol.c mm/memcontrol.c: remove unnecessary ; 2013-04-29 15:54:37 -07:00
memory_hotplug.c mm: walk_memory_range(): fix typo in comment 2013-04-29 15:54:28 -07:00
memory-failure.c HWPOISON: check dirty flag to match against clean page 2013-04-29 15:54:28 -07:00
memory.c THP: fix comment about memory barrier 2013-04-29 15:54:37 -07:00
mempolicy.c mm/mempolicy.c: fix sp_node_init() argument ordering 2013-03-08 15:05:34 -08:00
mempool.c mempool: add @gfp_mask to mempool_create_node() 2012-06-25 11:53:47 +02:00
migrate.c mm/migrate: fix comment typo syncronous->synchronous 2013-04-29 15:54:35 -07:00
mincore.c swap: make each swap partition have one address_space 2013-02-23 17:50:17 -08:00
mlock.c Revert "mm: introduce VM_POPULATE flag to better deal with racy userspace programs" 2013-03-28 17:45:51 -07:00
mm_init.c mm: init: report on last-nid information stored in page->flags 2013-02-23 17:50:18 -08:00
mmap.c mm: reinititalise user and admin reserves if memory is added or removed 2013-04-29 15:54:37 -07:00
mmu_context.c
mmu_notifier.c hlist: drop the node parameter from iterators 2013-02-27 19:10:24 -08:00
mmzone.c mm: rename page struct field helpers 2013-02-23 17:50:18 -08:00
mprotect.c mm/mprotect.c: coding-style cleanups 2012-12-18 15:02:15 -08:00
mremap.c mm/rmap: rename anon_vma_unlock() => anon_vma_unlock_write() 2013-02-23 17:50:17 -08:00
msync.c
nobootmem.c mm: Add alloc_bootmem_low_pages_nopanic() 2013-01-29 19:32:59 -08:00
nommu.c mm: replace hardcoded 3% with admin_reserve_pages knob 2013-04-29 15:54:36 -07:00
oom_kill.c memcg, oom: provide more precise dump info while memcg oom happening 2013-02-23 17:50:08 -08:00
page_alloc.c page_alloc: make setup_nr_node_ids() usable for arch init code 2013-04-29 15:54:36 -07:00
page_cgroup.c memcontrol: use N_MEMORY instead N_HIGH_MEMORY 2012-12-12 17:38:32 -08:00
page_io.c mm: add support for direct_IO to highmem pages 2012-07-31 18:42:47 -07:00
page_isolation.c mm: fix zone_watermark_ok_safe() accounting of isolated pages 2013-01-04 16:11:46 -08:00
page-writeback.c mm: make snapshotting pages for stable writes a per-bio operation 2013-04-29 15:54:33 -07:00
pagewalk.c thp: change split_huge_page_pmd() interface 2012-12-12 17:38:31 -08:00
percpu-km.c
percpu-vm.c mm: fix kernel-doc warnings 2012-06-20 14:39:36 -07:00
percpu.c mm, percpu: Make sure percpu_alloc early parameter has an argument 2012-12-02 06:23:04 -08:00
pgtable-generic.c mm: Only flush the TLB when clearing an accessible pte 2012-12-11 14:28:34 +00:00
process_vm_access.c Fix: compat_rw_copy_check_uvector() misuse in aio, readv, writev, and security keys 2013-03-12 11:05:45 -07:00
quicklist.c
readahead.c switch simple cases of fget_light to fdget 2012-09-26 22:20:08 -04:00
rmap.c rmap: recompute pgoff for unmapping huge page 2013-04-29 15:54:28 -07:00
shmem.c mm/shmem.c: remove an ifdef 2013-04-29 15:54:28 -07:00
slab_common.c slab: propagate tunable values 2012-12-18 15:02:14 -08:00
slab.c taint: add explicit flag to show whether lock dep is still OK. 2013-01-21 17:17:57 +10:30
slab.h slab: propagate tunable values 2012-12-18 15:02:14 -08:00
slob.c mm: rename page struct field helpers 2013-02-23 17:50:18 -08:00
slub.c mm/slub.c: use register_hotmemory_notifier() 2013-04-29 15:54:36 -07:00
sparse-vmemmap.c sparse-vmemmap: specify vmemmap population range in bytes 2013-04-29 15:54:35 -07:00
sparse.c sparse-vmemmap: specify vmemmap population range in bytes 2013-04-29 15:54:35 -07:00
swap_state.c swap: add per-partition lock for swapfile 2013-02-23 17:50:17 -08:00
swap.c swap: make each swap partition have one address_space 2013-02-23 17:50:17 -08:00
swapfile.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-02-26 20:16:07 -08:00
truncate.c mm: drop vmtruncate 2012-12-20 18:46:29 -05:00
util.c swap: make each swap partition have one address_space 2013-02-23 17:50:17 -08:00
vmalloc.c kexec, vmalloc: export additional vmalloc layer information 2013-04-29 15:54:34 -07:00
vmscan.c mm/vmscan.c: minor cleanup for kswapd 2013-04-29 15:54:29 -07:00
vmstat.c mm: remove CONFIG_HOTPLUG ifdefs 2013-04-29 15:54:37 -07:00