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| author | Miaohe Lin <linmiaohe@huawei.com> | 2021-02-25 17:18:03 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-07-11 12:49:27 +0200 |
| commit | 420afb489a1f6981cbe2fb9ee10007dba878e223 (patch) | |
| tree | 90c9066afc25ffe57dc72e47b0f06de738f69bef /mm/rmap.c | |
| parent | 784445344c9e7cdef2a2a724fab34243933a91dc (diff) | |
| download | linux-stable-420afb489a1f6981cbe2fb9ee10007dba878e223.tar.gz linux-stable-420afb489a1f6981cbe2fb9ee10007dba878e223.tar.bz2 linux-stable-420afb489a1f6981cbe2fb9ee10007dba878e223.zip | |
mm/rmap: use page_not_mapped in try_to_unmap()
[ Upstream commit b7e188ec98b1644ff70a6d3624ea16aadc39f5e0 ]
page_mapcount_is_zero() calculates accurately how many mappings a hugepage
has in order to check against 0 only. This is a waste of cpu time. We
can do this via page_not_mapped() to save some possible atomic_read
cycles. Remove the function page_mapcount_is_zero() as it's not used
anymore and move page_not_mapped() above try_to_unmap() to avoid
identifier undeclared compilation error.
Link: https://lkml.kernel.org/r/20210130084904.35307-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'mm/rmap.c')
| -rw-r--r-- | mm/rmap.c | 11 |
1 files changed, 3 insertions, 8 deletions
diff --git a/mm/rmap.c b/mm/rmap.c index 69ce68616cbf..70872d5b203c 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1682,9 +1682,9 @@ static bool invalid_migration_vma(struct vm_area_struct *vma, void *arg) return is_vma_temporary_stack(vma); } -static int page_mapcount_is_zero(struct page *page) +static int page_not_mapped(struct page *page) { - return !total_mapcount(page); + return !page_mapped(page); } /** @@ -1702,7 +1702,7 @@ bool try_to_unmap(struct page *page, enum ttu_flags flags) struct rmap_walk_control rwc = { .rmap_one = try_to_unmap_one, .arg = (void *)flags, - .done = page_mapcount_is_zero, + .done = page_not_mapped, .anon_lock = page_lock_anon_vma_read, }; @@ -1726,11 +1726,6 @@ bool try_to_unmap(struct page *page, enum ttu_flags flags) return !page_mapcount(page) ? true : false; } -static int page_not_mapped(struct page *page) -{ - return !page_mapped(page); -} - /** * try_to_munlock - try to munlock a page * @page: the page to be munlocked |