mm: thp: don't need to drain lru cache when splitting and mlocking THP
authorYang Shi <yang.shi@linux.alibaba.com>
Wed, 3 Jun 2020 23:03:37 +0000 (16:03 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 4 Jun 2020 03:09:49 +0000 (20:09 -0700)
commit67e4eb076840c7d199ebae0a8825c89a5b07d162
tree2cc80a3f7a0a59b7d27eb50a53d5139722077b46
parent885902531586d5a20a74099c1357bfdc982befe3
mm: thp: don't need to drain lru cache when splitting and mlocking THP

Since commit 8f182270dfec ("mm/swap.c: flush lru pvecs on compound page
arrival") THP would not stay in pagevec anymore.  So the optimization made
by commit d965432234db ("thp: increase split_huge_page() success rate")
doesn't make sense anymore, which tries to unpin munlocked THPs from
pagevec by draining pagevec.

Draining lru cache before isolating THP in mlock path is also unnecessary.
b676b293fb48 ("mm, thp: fix mapped pages avoiding unevictable list on
mlock") added it and 9a73f61bdb8a ("thp, mlock: do not mlock PTE-mapped
file huge pages") accidentally carried it over after the above
optimization went in.

Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Link: http://lkml.kernel.org/r/1585946493-7531-1-git-send-email-yang.shi@linux.alibaba.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/huge_memory.c