diff options
| author | David Rientjes <rientjes@google.com> | 2012-05-29 15:06:26 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-05-29 16:22:20 -0700 |
| commit | 6f60b69d8cabbf7c0daf879cae4d09ac0776f4b4 (patch) | |
| tree | b9ee18ec2ca4be000197a8a3ebb1b8e9015dc599 /mm/huge_memory.c | |
| parent | 096a7cf44712ab531101bb4689f75f7fcd9b9f18 (diff) | |
| download | lwn-6f60b69d8cabbf7c0daf879cae4d09ac0776f4b4.tar.gz lwn-6f60b69d8cabbf7c0daf879cae4d09ac0776f4b4.zip | |
mm, thp: drop page_table_lock to uncharge memcg pages
mm->page_table_lock is hotly contested for page fault tests and isn't
necessary to do mem_cgroup_uncharge_page() in do_huge_pmd_wp_page().
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/huge_memory.c')
| -rw-r--r-- | mm/huge_memory.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index edfeb8cb23df..d0def42c121b 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -973,8 +973,10 @@ int do_huge_pmd_wp_page(struct mm_struct *mm, struct vm_area_struct *vma, spin_lock(&mm->page_table_lock); put_page(page); if (unlikely(!pmd_same(*pmd, orig_pmd))) { + spin_unlock(&mm->page_table_lock); mem_cgroup_uncharge_page(new_page); put_page(new_page); + goto out; } else { pmd_t entry; VM_BUG_ON(!PageHead(page)); |