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>
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index a90f51d..7b5b5de 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1231,12 +1231,12 @@
if (wbc->for_reclaim)
goto redirty_out;
- mutex_lock(&sbi->node_write);
+ down_read(&sbi->node_write);
set_page_writeback(page);
write_node_page(sbi, page, &fio, nid, ni.blk_addr, &new_addr);
set_node_addr(sbi, &ni, new_addr, is_fsync_dnode(page));
dec_page_count(sbi, F2FS_DIRTY_NODES);
- mutex_unlock(&sbi->node_write);
+ up_read(&sbi->node_write);
unlock_page(page);
return 0;