f2fs: reduce competition among node page writes

We do not need to block on ->node_write among different node page writers e.g.
fsync/flush, unless we have a node page writer from write_checkpoint.
So it's better use rw_semaphore instead of mutex type for ->node_write to
promote performance.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

1 files changed, 3 insertions, 3 deletions

diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index cea20b810f44..6aeed5bada52 100644
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -762,10 +762,10 @@ retry_flush_dents:
          * until finishing nat/sit flush.
          */
 retry_flush_nodes:
-        mutex_lock(&sbi->node_write);
+        down_write(&sbi->node_write);
 
         if (get_pages(sbi, F2FS_DIRTY_NODES)) {
-                mutex_unlock(&sbi->node_write);
+                up_write(&sbi->node_write);
                 sync_node_pages(sbi, 0, &wbc);
                 goto retry_flush_nodes;
         }
@@ -774,7 +774,7 @@ retry_flush_nodes:
 
 static void unblock_operations(struct f2fs_sb_info *sbi)
 {
-        mutex_unlock(&sbi->node_write);
+        up_write(&sbi->node_write);
         f2fs_unlock_all(sbi);
 }