The patch titled
Subject: mm/thp: remove code path which never got into
has been added to the -mm tree. Its filename is
mm-thp-remove-code-path-which-never-got-into.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-thp-remove-code-path-which-never-got-into.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-thp-remove-code-path-which-never-got-into.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: Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx>
Subject: mm/thp: remove code path which never got into
split_huge_page() will never call on a page which isn't on lru list, so
this code never got a chance to run, and should not be run, to add tail
pages on a lru list which head page isn't there.
Although the bug was never triggered, it'better be removed for code
correctness, and add a warn for unexpected calling.
Link: http://lkml.kernel.org/r/1597144232-11370-5-git-send-email-alex.shi@xxxxxxxxxxxxxxxxx
Signed-off-by: Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx>
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: Roman Gushchin <guro@xxxxxx>
Cc: Vladimir Davydov <vdavydov.dev@xxxxxxxxx>
Cc: Wei Yang <richard.weiyang@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/huge_memory.c | 13 ++-----------
1 file changed, 2 insertions(+), 11 deletions(-)
--- a/mm/huge_memory.c~mm-thp-remove-code-path-which-never-got-into
+++ a/mm/huge_memory.c
@@ -2330,17 +2330,8 @@ static void lru_add_page_tail(struct pag
/* page reclaim is reclaiming a huge page */
get_page(page_tail);
list_add_tail(&page_tail->lru, list);
- } else {
- /*
- * Head page has not yet been counted, as an hpage,
- * so we must account for each subpage individually.
- *
- * Put page_tail on the list at the correct position
- * so they all end up in order.
- */
- add_page_to_lru_list_tail(page_tail, lruvec,
- page_lru(page_tail));
- }
+ } else
+ VM_WARN_ON(!PageLRU(head));
}
static void __split_huge_page_tail(struct page *head, int tail,
_
Patches currently in -mm which might be from alex.shi@xxxxxxxxxxxxxxxxx are
mm-memcg-warning-on-memcg-after-readahead-page-charged.patch
mm-memcg-remove-useless-check-on-page-mem_cgroup.patch
mm-thp-move-lru_add_page_tail-func-to-huge_memoryc.patch
mm-thp-clean-up-lru_add_page_tail.patch
mm-thp-remove-code-path-which-never-got-into.patch
mm-thp-narrow-lru-locking.patch
