From: Huaisheng Ye <yehs1@lenovo.com>
Date: Mon, 2 Sep 2019 10:04:50 +0000 (+0800)
Subject: dm writecache: skip writecache_wait for pmem mode
X-Git-Tag: v5.4-rc1~90^2~8
X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=6d1959138c8bdaf69f1116c86c77e6733db6ab34;p=linux.git

dm writecache: skip writecache_wait for pmem mode

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@lenovo.com>
Signed-off-by: Huaisheng Ye <yehs1@lenovo.com>
Acked-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---

diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c
index c48194703dbc..d06b8aa41e26 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));