The patch titled
Subject: mm/rmap: use page_not_mapped in try_to_unmap()
has been added to the -mm tree. Its filename is
mm-rmap-use-page_not_mapped-in-try_to_unmap.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-rmap-use-page_not_mapped-in-try_to_unmap.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-rmap-use-page_not_mapped-in-try_to_unmap.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Subject: mm/rmap: use page_not_mapped in try_to_unmap()
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@xxxxxxxxxx
Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/rmap.c | 11 +++--------
1 file changed, 3 insertions(+), 8 deletions(-)
--- a/mm/rmap.c~mm-rmap-use-page_not_mapped-in-try_to_unmap
+++ a/mm/rmap.c
@@ -1736,9 +1736,9 @@ static bool invalid_migration_vma(struct
return vma_is_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);
}
/**
@@ -1756,7 +1756,7 @@ bool try_to_unmap(struct page *page, enu
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,
};
@@ -1780,11 +1780,6 @@ bool try_to_unmap(struct page *page, enu
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
_
Patches currently in -mm which might be from linmiaohe@xxxxxxxxxx are
mm-rmap-fix-potential-pte_unmap-on-an-not-mapped-pte.patch
mm-page_owner-use-helper-function-zone_end_pfn-to-get-end_pfn.patch
mm-fix-potential-pte_unmap_unlock-pte-error.patch
mm-hugetlb-fix-potential-double-free-in-hugetlb_register_node-error-path.patch
mm-hugetlb-avoid-unnecessary-hugetlb_acct_memory-call.patch
mm-hugetlb-use-helper-huge_page_order-and-pages_per_huge_page.patch
mm-hugetlb-fix-use-after-free-when-subpool-max_hpages-accounting-is-not-enabled.patch
mm-hugetlb-fix-some-comment-typos.patch
mm-workingsetc-avoid-unnecessary-max_nodes-estimation-in-count_shadow_nodes.patch
z3fold-remove-unused-attribute-for-release_z3fold_page.patch
z3fold-simplify-the-zhdr-initialization-code-in-init_z3fold_page.patch
mm-compaction-remove-duplicated-vm_bug_on_page-pagelocked.patch
mm-mempolicy-use-helper-range_in_vma-in-queue_pages_test_walk.patch
hugetlbfs-remove-useless-bug_oninode-in-hugetlbfs_setattr.patch
hugetlbfs-use-helper-macro-default_hstate-in-init_hugetlbfs_fs.patch
hugetlbfs-correct-obsolete-function-name-in-hugetlbfs_read_iter.patch
hugetlbfs-remove-meaningless-variable-avoid_reserve.patch
hugetlbfs-make-hugepage-size-conversion-more-readable.patch
hugetlbfs-correct-some-obsolete-comments-about-inode-i_mutex.patch
hugetlbfs-fix-some-comment-typos.patch
mm-memory_hotplug-use-helper-function-zone_end_pfn-to-get-end_pfn.patch
mm-rmap-correct-some-obsolete-comments-of-anon_vma.patch
mm-rmap-remove-unneeded-semicolon-in-page_not_mapped.patch
mm-rmap-fix-obsolete-comment-in-__page_check_anon_rmap.patch
mm-rmap-use-page_not_mapped-in-try_to_unmap.patch
mm-zsmallocc-convert-to-use-kmem_cache_zalloc-in-cache_alloc_zspage.patch
