[PATCH] dm writecache: skip writecache_wait for pmem mode

[Huaisheng Ye]

From: Huaisheng Ye <yehs1@xxxxxxxxxx>

The array bio_in_progress[2] only have chance to be increased and
decreased with ssd mode. For pmem mode, they are not involved at all.
So skip writecache_wait_for_ios in writecache_flush for pmem.

Suggested-by: Doris Yu <tyu1@xxxxxxxxxx>
Signed-off-by: Huaisheng Ye <yehs1@xxxxxxxxxx>
---
 drivers/md/dm-writecache.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c
index c481947..d06b8aa 100644
--- a/drivers/md/dm-writecache.c
+++ b/drivers/md/dm-writecache.c
@@ -726,7 +726,8 @@ static void writecache_flush(struct dm_writecache *wc)
 	}
 	writecache_commit_flushed(wc);
 
-	writecache_wait_for_ios(wc, WRITE);
+	if (!WC_MODE_PMEM(wc))
+		writecache_wait_for_ios(wc, WRITE);
 
 	wc->seq_count++;
 	pmem_assign(sb(wc)->seq_count, cpu_to_le64(wc->seq_count));
-- 
1.8.3.1