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| author | Joonsoo Kim <iamjoonsoo.kim@lge.com> | 2020-08-12 04:37:20 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-08-12 20:58:02 +0300 |
| commit | 9933a0c8a5396df6dbaef809a9ee4ad64ebc3abe (patch) | |
| tree | 9eeae019998d23d566f69af2f2cc8b52e22439a1 /mm/migrate.c | |
| parent | d92bbc2719bd2be237ee336113b63492a6baca3b (diff) | |
| download | linux-9933a0c8a5396df6dbaef809a9ee4ad64ebc3abe.tar.xz | |
mm/migrate: clear __GFP_RECLAIM to make the migration callback consistent with regular THP allocations
new_page_nodemask is a migration callback and it tries to use a common gfp
flags for the target page allocation whether it is a base page or a THP.
The later only adds GFP_TRANSHUGE to the given mask. This results in the
allocation being slightly more aggressive than necessary because the
resulting gfp mask will contain also __GFP_RECLAIM_KSWAPD. THP
allocations usually exclude this flag to reduce over eager background
reclaim during a high THP allocation load which has been seen during large
mmaps initialization. There is no indication that this is a problem for
migration as well but theoretically the same might happen when migrating
large mappings to a different node. Make the migration callback
consistent with regular THP allocations.
[akpm@linux-foundation.org: fix comment typo, per Vlastimil]
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Roman Gushchin <guro@fb.com>
Link: http://lkml.kernel.org/r/1594622517-20681-5-git-send-email-iamjoonsoo.kim@lge.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/migrate.c')
| -rw-r--r-- | mm/migrate.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/mm/migrate.c b/mm/migrate.c index 8d084e9bc13b..46cca5c2ebff 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -1554,6 +1554,11 @@ struct page *new_page_nodemask(struct page *page, } if (PageTransHuge(page)) { + /* + * clear __GFP_RECLAIM to make the migration callback + * consistent with regular THP allocations. + */ + gfp_mask &= ~__GFP_RECLAIM; gfp_mask |= GFP_TRANSHUGE; order = HPAGE_PMD_ORDER; } |