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author | James Morse <james.morse@arm.com> | 2016-10-08 02:00:12 +0200 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-10-08 03:46:28 +0200 |
commit | 0247f3f4d78a475cd3181dc9fc162fdef773aaaa (patch) | |
tree | 2e7c179bbed1aa445b8305071dcbf44ce7d299a3 | |
parent | thp: reduce usage of huge zero page's atomic counter (diff) | |
download | linux-0247f3f4d78a475cd3181dc9fc162fdef773aaaa.tar.xz linux-0247f3f4d78a475cd3181dc9fc162fdef773aaaa.zip |
mm/memcontrol.c: make the walk_page_range() limit obvious
mem_cgroup_count_precharge() and mem_cgroup_move_charge() both call
walk_page_range() on the range 0 to ~0UL, neither provide a pte_hole
callback, which causes the current implementation to skip non-vma
regions. This is all fine but follow up changes would like to make
walk_page_range more generic so it is better to be explicit about which
range to traverse so let's use highest_vm_end to explicitly traverse
only user mmaped memory.
[mhocko@kernel.org: rewrote changelog]
Link: http://lkml.kernel.org/r/1472655897-22532-1-git-send-email-james.morse@arm.com
Signed-off-by: James Morse <james.morse@arm.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r-- | mm/memcontrol.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 5579e762b1ce..0739d4129a93 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -4681,7 +4681,8 @@ static unsigned long mem_cgroup_count_precharge(struct mm_struct *mm) .mm = mm, }; down_read(&mm->mmap_sem); - walk_page_range(0, ~0UL, &mem_cgroup_count_precharge_walk); + walk_page_range(0, mm->highest_vm_end, + &mem_cgroup_count_precharge_walk); up_read(&mm->mmap_sem); precharge = mc.precharge; @@ -4969,7 +4970,8 @@ retry: * When we have consumed all precharges and failed in doing * additional charge, the page walk just aborts. */ - walk_page_range(0, ~0UL, &mem_cgroup_move_charge_walk); + walk_page_range(0, mc.mm->highest_vm_end, &mem_cgroup_move_charge_walk); + up_read(&mc.mm->mmap_sem); atomic_dec(&mc.from->moving_account); } |