4.14-stable review patch. If anyone has any objections, please let me know.
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From: Chao Yu yuchao0@huawei.com
[ Upstream commit 4b270a8cc5047682f0a3f3f9af3b498408dbd2bc ]
In synchronous scenario, like in checkpoint(), we are going to flush dirty node pages to device synchronously, we can easily failed writebacking node page due to trylock_page() failure, especially in condition of intensive lock competition, which can cause long latency of checkpoint(). So let's use lock_page() in synchronous scenario to avoid this issue.
Signed-off-by: Yunlei He heyunlei@huawei.com Signed-off-by: Chao Yu yuchao0@huawei.com Signed-off-by: Jaegeuk Kim jaegeuk@kernel.org Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/f2fs/node.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
--- a/fs/f2fs/node.c +++ b/fs/f2fs/node.c @@ -1610,7 +1610,9 @@ next_step: !is_cold_node(page))) continue; lock_node: - if (!trylock_page(page)) + if (wbc->sync_mode == WB_SYNC_ALL) + lock_page(page); + else if (!trylock_page(page)) continue;
if (unlikely(page->mapping != NODE_MAPPING(sbi))) {