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| author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2016-01-15 16:53:07 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-01-15 17:56:32 -0800 |
| commit | 3ac808fdd2b835547af81de75c813cf7ba2ab58f (patch) | |
| tree | 0c3becb6bc03ab26490c937fe8031419dad91b1e /mm/memcontrol.c | |
| parent | f765f540598a129dc4bb6f698fd4acc92f296c14 (diff) | |
| download | lwn-3ac808fdd2b835547af81de75c813cf7ba2ab58f.tar.gz lwn-3ac808fdd2b835547af81de75c813cf7ba2ab58f.zip | |
mm, thp: remove compound_lock()
We are going to use migration entries to stabilize page counts. It
means we don't need compound_lock() for that.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Jerome Marchand <jmarchan@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/memcontrol.c')
| -rw-r--r-- | mm/memcontrol.c | 11 |
1 files changed, 3 insertions, 8 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 311fd2b71bae..db2a5d9ad886 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2433,9 +2433,7 @@ void __memcg_kmem_uncharge(struct page *page, int order) /* * Because tail pages are not marked as "used", set it. We're under - * zone->lru_lock, 'splitting on pmd' and compound_lock. - * charge/uncharge will be never happen and move_account() is done under - * compound_lock(), so we don't have to take care of races. + * zone->lru_lock and migration entries setup in all page mappings. */ void mem_cgroup_split_huge_fixup(struct page *head) { @@ -4507,9 +4505,7 @@ static struct page *mc_handle_file_pte(struct vm_area_struct *vma, * @from: mem_cgroup which the page is moved from. * @to: mem_cgroup which the page is moved to. @from != @to. * - * The caller must confirm following. - * - page is not on LRU (isolate_page() is useful.) - * - compound_lock is held when nr_pages > 1 + * The caller must make sure the page is not on LRU (isolate_page() is useful.) * * This function doesn't do "charge" to new cgroup and doesn't do "uncharge" * from old cgroup. @@ -4868,8 +4864,7 @@ static int mem_cgroup_move_charge_pte_range(pmd_t *pmd, struct page *page; /* - * We don't take compound_lock() here but no race with splitting thp - * happens because: + * No race with splitting thp happens because: * - if pmd_trans_huge_lock() returns 1, the relevant thp is not * under splitting, which means there's no concurrent thp split, * - if another thread runs into split_huge_page() just after we |