The patch titled
Subject: mm, hugetlb, hwpoison: separate branch for free and in-use hugepage
has been added to the -mm tree. Its filename is
mm-hugetlb-hwpoison-separate-branch-for-free-and-in-use-hugepage.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-hugetlb-hwpoison-separate-branch-for-free-and-in-use-hugepage.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-hugetlb-hwpoison-separate-branch-for-free-and-in-use-hugepage.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: Naoya Horiguchi <naoya.horiguchi@xxxxxxx>
Subject: mm, hugetlb, hwpoison: separate branch for free and in-use hugepage
We know that HPageFreed pages should have page refcount 0, so
get_page_unless_zero() always fails and returns 0. So explicitly separate
the branch based on page state for minor optimization and better
readability.
Link: https://lkml.kernel.org/r/20220415041848.GA3034499@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@xxxxxxx>
Suggested-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
Suggested-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Reviewed-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
Reviewed-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/hugetlb.c | 4 +++-
mm/memory-failure.c | 4 +++-
2 files changed, 6 insertions(+), 2 deletions(-)
--- a/mm/hugetlb.c~mm-hugetlb-hwpoison-separate-branch-for-free-and-in-use-hugepage
+++ a/mm/hugetlb.c
@@ -6831,7 +6831,9 @@ int get_hwpoison_huge_page(struct page *
spin_lock_irq(&hugetlb_lock);
if (PageHeadHuge(page)) {
*hugetlb = true;
- if (HPageFreed(page) || HPageMigratable(page))
+ if (HPageFreed(page))
+ ret = 0;
+ else if (HPageMigratable(page))
ret = get_page_unless_zero(page);
else
ret = -EBUSY;
--- a/mm/memory-failure.c~mm-hugetlb-hwpoison-separate-branch-for-free-and-in-use-hugepage
+++ a/mm/memory-failure.c
@@ -1518,7 +1518,9 @@ int __get_huge_page_for_hwpoison(unsigne
if (flags & MF_COUNT_INCREASED) {
ret = 1;
count_increased = true;
- } else if (HPageFreed(head) || HPageMigratable(head)) {
+ } else if (HPageFreed(head)) {
+ ret = 0;
+ } else if (HPageMigratable(head)) {
ret = get_page_unless_zero(head);
if (ret)
count_increased = true;
_
Patches currently in -mm which might be from naoya.horiguchi@xxxxxxx are
mm-hwpoison-fix-race-between-hugetlb-free-demotion-and-memory_failure_hugetlb.patch
mm-hwpoison-put-page-in-already-hwpoisoned-case-with-mf_count_increased.patch
revert-mm-memory-failurec-fix-race-with-changing-page-compound-again.patch
mm-hugetlb-hwpoison-separate-branch-for-free-and-in-use-hugepage.patch
