[PATCH v3 15/15] mm,hwpoison: introduce MF_MSG_UNSPLIT_THP

From: nao . horiguchi
Date: Wed Jun 24 2020 - 11:02:42 EST


From: Naoya Horiguchi <naoya.horiguchi@xxxxxxx>

memory_failure() is supposed to call action_result() when it handles
a memory error event, but there's one missing case. So let's add it.

I find that include/ras/ras_event.h has some other MF_MSG_* undefined,
so this patch also adds them.

Signed-off-by: Naoya Horiguchi <naoya.horiguchi@xxxxxxx>
---
include/linux/mm.h | 1 +
include/ras/ras_event.h | 3 +++
mm/memory-failure.c | 5 ++++-
3 files changed, 8 insertions(+), 1 deletion(-)

diff --git v5.8-rc1-mmots-2020-06-20-21-44/include/linux/mm.h v5.8-rc1-mmots-2020-06-20-21-44_patched/include/linux/mm.h
index d708033c50c0..10ee48f05f68 100644
--- v5.8-rc1-mmots-2020-06-20-21-44/include/linux/mm.h
+++ v5.8-rc1-mmots-2020-06-20-21-44_patched/include/linux/mm.h
@@ -3033,6 +3033,7 @@ enum mf_action_page_type {
MF_MSG_BUDDY,
MF_MSG_BUDDY_2ND,
MF_MSG_DAX,
+ MF_MSG_UNSPLIT_THP,
MF_MSG_UNKNOWN,
};

diff --git v5.8-rc1-mmots-2020-06-20-21-44/include/ras/ras_event.h v5.8-rc1-mmots-2020-06-20-21-44_patched/include/ras/ras_event.h
index 36c5c5e38c1d..0bdbc0d17d2f 100644
--- v5.8-rc1-mmots-2020-06-20-21-44/include/ras/ras_event.h
+++ v5.8-rc1-mmots-2020-06-20-21-44_patched/include/ras/ras_event.h
@@ -361,6 +361,7 @@ TRACE_EVENT(aer_event,
EM ( MF_MSG_POISONED_HUGE, "huge page already hardware poisoned" ) \
EM ( MF_MSG_HUGE, "huge page" ) \
EM ( MF_MSG_FREE_HUGE, "free huge page" ) \
+ EM ( MF_MSG_NON_PMD_HUGE, "non-pmd-sized huge page" ) \
EM ( MF_MSG_UNMAP_FAILED, "unmapping failed page" ) \
EM ( MF_MSG_DIRTY_SWAPCACHE, "dirty swapcache page" ) \
EM ( MF_MSG_CLEAN_SWAPCACHE, "clean swapcache page" ) \
@@ -373,6 +374,8 @@ TRACE_EVENT(aer_event,
EM ( MF_MSG_TRUNCATED_LRU, "already truncated LRU page" ) \
EM ( MF_MSG_BUDDY, "free buddy page" ) \
EM ( MF_MSG_BUDDY_2ND, "free buddy page (2nd try)" ) \
+ EM ( MF_MSG_DAX, "dax page" ) \
+ EM ( MF_MSG_UNSPLIT_THP, "unsplit thp" ) \
EMe ( MF_MSG_UNKNOWN, "unknown page" )

/*
diff --git v5.8-rc1-mmots-2020-06-20-21-44/mm/memory-failure.c v5.8-rc1-mmots-2020-06-20-21-44_patched/mm/memory-failure.c
index 9ad3198a3954..e57cfe0606f5 100644
--- v5.8-rc1-mmots-2020-06-20-21-44/mm/memory-failure.c
+++ v5.8-rc1-mmots-2020-06-20-21-44_patched/mm/memory-failure.c
@@ -586,6 +586,7 @@ static const char * const action_page_types[] = {
[MF_MSG_BUDDY] = "free buddy page",
[MF_MSG_BUDDY_2ND] = "free buddy page (2nd try)",
[MF_MSG_DAX] = "dax page",
+ [MF_MSG_UNSPLIT_THP] = "unsplit thp",
[MF_MSG_UNKNOWN] = "unknown page",
};

@@ -1376,8 +1377,10 @@ int memory_failure(unsigned long pfn, int flags)
}

if (PageTransHuge(hpage)) {
- if (try_to_split_thp_page(p, "Memory Failure") < 0)
+ if (try_to_split_thp_page(p, "Memory Failure") < 0) {
+ action_result(pfn, MF_MSG_UNSPLIT_THP, MF_IGNORED);
return -EBUSY;
+ }
VM_BUG_ON_PAGE(!page_count(p), p);
}

--
2.17.1