[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-Id: <1658405108-100658-1-git-send-email-baolin.wang@linux.alibaba.com>
Date: Thu, 21 Jul 2022 20:05:08 +0800
From: Baolin Wang <baolin.wang@...ux.alibaba.com>
To: akpm@...ux-foundation.org
Cc: ying.huang@...el.com, ziy@...dia.com, shy828301@...il.com,
baolin.wang@...ux.alibaba.com, linux-mm@...ck.org,
linux-kernel@...r.kernel.org
Subject: [PATCH] mm: migrate: Do not retry 10 times for the subpages of fail-to-migrate THP
If THP is failed to migrate due to -ENOSYS or -ENOMEM case, the THP will
be split, and the subpages of fail-to-migrate THP will be tried to migrate
again, so we should not account the retry counter in the second loop, since
we already accounted 'nr_thp_failed' in the first loop.
Moreover we also do not need retry 10 times for -EAGAIN case for the subpages
of fail-to-migrate THP in the second loop, since we already regarded the
THP as migration failure, and save some migration time (for the worst case,
will try 512 * 10 times) according to previous discussion [1].
[1] https://lore.kernel.org/linux-mm/87r13a7n04.fsf@yhuang6-desk2.ccr.corp.intel.com/
Signed-off-by: Baolin Wang <baolin.wang@...ux.alibaba.com>
---
Note, this patch is based on the patch set [1] from Huang Ying.
[1] https://lore.kernel.org/linux-mm/20220711084948.274787-1-ying.huang@intel.com/
---
mm/migrate.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/mm/migrate.c b/mm/migrate.c
index 8429206..e36a084 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -1507,7 +1507,7 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page,
case -EAGAIN:
if (is_thp)
thp_retry++;
- else
+ else if (!no_subpage_counting)
retry++;
nr_retry_pages += nr_subpages;
break;
@@ -1533,8 +1533,7 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page,
}
}
}
- if (!no_subpage_counting)
- nr_failed += retry;
+ nr_failed += retry;
nr_thp_failed += thp_retry;
nr_failed_pages += nr_retry_pages;
/*
--
1.8.3.1
Powered by blists - more mailing lists