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| author | Johannes Weiner <hannes@cmpxchg.org> | 2014-08-06 16:05:49 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-08-06 18:01:17 -0700 |
| commit | d51d885bbb137cc8e1704e76be1846c5e0d5e8b4 (patch) | |
| tree | fd79f2485ac47325386873cbe0cd7666f0339725 | |
| parent | 28c34c291e746aab1c2bfd6d6609b2e47fa0978b (diff) | |
| download | linux-d51d885bbb137cc8e1704e76be1846c5e0d5e8b4.tar.gz | |
mm: huge_memory: use GFP_TRANSHUGE when charging huge pages
Transparent huge page charges prefer falling back to regular pages
rather than spending a lot of time in direct reclaim.
Desired reclaim behavior is usually declared in the gfp mask, but THP
charges use GFP_KERNEL and then rely on the fact that OOM is disabled
for THP charges, and that OOM-disabled charges don't retry reclaim.
Needless to say, this is anything but obvious and quite error prone.
Convert THP charges to use GFP_TRANSHUGE instead, which implies
__GFP_NORETRY, to indicate the low-latency requirement.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vladimir Davydov <vdavydov@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | mm/huge_memory.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 4b95ff4120f5a..24e354c2b59e5 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -827,7 +827,7 @@ int do_huge_pmd_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma, count_vm_event(THP_FAULT_FALLBACK); return VM_FAULT_FALLBACK; } - if (unlikely(mem_cgroup_charge_anon(page, mm, GFP_KERNEL))) { + if (unlikely(mem_cgroup_charge_anon(page, mm, GFP_TRANSHUGE))) { put_page(page); count_vm_event(THP_FAULT_FALLBACK); return VM_FAULT_FALLBACK; @@ -1132,7 +1132,7 @@ alloc: goto out; } - if (unlikely(mem_cgroup_charge_anon(new_page, mm, GFP_KERNEL))) { + if (unlikely(mem_cgroup_charge_anon(new_page, mm, GFP_TRANSHUGE))) { put_page(new_page); if (page) { split_huge_page(page); @@ -2399,7 +2399,7 @@ static void collapse_huge_page(struct mm_struct *mm, if (!new_page) return; - if (unlikely(mem_cgroup_charge_anon(new_page, mm, GFP_KERNEL))) + if (unlikely(mem_cgroup_charge_anon(new_page, mm, GFP_TRANSHUGE))) return; /* |