The patch titled
Subject: thp: allow a hwpoisoned head page to be put back to LRU
has been added to the -mm tree. Its filename is
thp-allow-a-hwpoisoned-head-page-to-be-put-back-to-lru.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/SubmitChecklist when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Dean Nelson <dnelson@xxxxxxxxxx>
Subject: thp: allow a hwpoisoned head page to be put back to LRU
Andrea Arcangeli pointed out to me that a check in __memory_failure()
which was intended to prevent THP tail pages from being checked for the
absence of the PG_lru flag (something that is always the case), was also
preventing THP head pages from being checked.
A THP head page could actually benefit from the call to shake_page() by
ending up being put back to a LRU, provided it had been waiting in a
pagevec array.
Andrea suggested that the "!PageTransCompound(p)" in the if-statement
should be replaced by a "!PageTransTail(p)", thus allowing THP head pages
to be checked and possibly shaken.
Signed-off-by: Dean Nelson <dnelson@xxxxxxxxxx>
Cc: Jin Dongming <jin.dongming@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Andrea Arcangeli <aarcange@xxxxxxxxxx>
Cc: Andi Kleen <andi@xxxxxxxxxxxxxx>
Cc: Hidetoshi Seto <seto.hidetoshi@xxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/page-flags.h | 20 ++++++++++++++++++++
mm/memory-failure.c | 2 +-
2 files changed, 21 insertions(+), 1 deletion(-)
diff -puN include/linux/page-flags.h~thp-allow-a-hwpoisoned-head-page-to-be-put-back-to-lru include/linux/page-flags.h
--- a/include/linux/page-flags.h~thp-allow-a-hwpoisoned-head-page-to-be-put-back-to-lru
+++ a/include/linux/page-flags.h
@@ -415,11 +415,26 @@ static inline int PageTransHuge(struct p
return PageHead(page);
}
+/*
+ * PageTransCompound returns true for both transparent huge pages
+ * and hugetlbfs pages, so it should only be called when it's known
+ * that hugetlbfs pages aren't involved.
+ */
static inline int PageTransCompound(struct page *page)
{
return PageCompound(page);
}
+/*
+ * PageTransTail returns true for both transparent huge pages
+ * and hugetlbfs pages, so it should only be called when it's known
+ * that hugetlbfs pages aren't involved.
+ */
+static inline int PageTransTail(struct page *page)
+{
+ return PageTail(page);
+}
+
#else
static inline int PageTransHuge(struct page *page)
@@ -431,6 +446,11 @@ static inline int PageTransCompound(stru
{
return 0;
}
+
+static inline int PageTransTail(struct page *page)
+{
+ return 0;
+}
#endif
#ifdef CONFIG_MMU
diff -puN mm/memory-failure.c~thp-allow-a-hwpoisoned-head-page-to-be-put-back-to-lru mm/memory-failure.c
--- a/mm/memory-failure.c~thp-allow-a-hwpoisoned-head-page-to-be-put-back-to-lru
+++ a/mm/memory-failure.c
@@ -1089,7 +1089,7 @@ int memory_failure(unsigned long pfn, in
* The check (unnecessarily) ignores LRU pages being isolated and
* walked by the page reclaim code, however that's not a big loss.
*/
- if (!PageHuge(p) && !PageTransCompound(p)) {
+ if (!PageHuge(p) && !PageTransTail(p)) {
if (!PageLRU(p))
shake_page(p, 0);
if (!PageLRU(p)) {
_
Subject: Subject: thp: allow a hwpoisoned head page to be put back to LRU
Patches currently in -mm which might be from dnelson@xxxxxxxxxx are
thp-allow-a-hwpoisoned-head-page-to-be-put-back-to-lru.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
