mm/hugetlb: improve locking in dissolve_free_huge_pages()

For every pfn aligned to minimum_order, dissolve_free_huge_pages() will
call dissolve_free_huge_page() which takes the hugetlb spinlock, even if
the page is not huge at all or a hugepage that is in-use.

Improve this by doing the PageHuge() and page_count() checks already in
dissolve_free_huge_pages() before calling dissolve_free_huge_page().  In
dissolve_free_huge_page(), when holding the spinlock, those checks need
to be revalidated.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Gerald Schaefer <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Acked-by: Naoya Horiguchi <[email protected]>
Cc: "Kirill A . Shutemov" <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Mike Kravetz <[email protected]>
Cc: "Aneesh Kumar K . V" <[email protected]>
Cc: Martin Schwidefsky <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Rui Teng <[email protected]>
Cc: Dave Hansen <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions