From: Tang Junhui <tang.junhui@zte.com.cn>
Date: Wed, 6 Sep 2017 06:25:53 +0000 (+0800)
Subject: bcache: do not subtract sectors_to_gc for bypassed IO
X-Git-Tag: v4.4.89~6
X-Git-Url: http://git.hungrycats.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0471f58e18e60dcdbd89f882dc0fa6370b94cd48;p=linux

bcache: do not subtract sectors_to_gc for bypassed IO

commit 69daf03adef5f7bc13e0ac86b4b8007df1767aab upstream.

Since bypassed IOs use no bucket, so do not subtract sectors_to_gc to
trigger gc thread.

Signed-off-by: tang.junhui <tang.junhui@zte.com.cn>
Acked-by: Coly Li <colyli@suse.de>
Reviewed-by: Eric Wheeler <bcache@linux.ewheeler.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index 2410df1c2a05..6c4c7caea693 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -196,12 +196,12 @@ static void bch_data_insert_start(struct closure *cl)
 	struct data_insert_op *op = container_of(cl, struct data_insert_op, cl);
 	struct bio *bio = op->bio, *n;
 
-	if (atomic_sub_return(bio_sectors(bio), &op->c->sectors_to_gc) < 0)
-		wake_up_gc(op->c);
-
 	if (op->bypass)
 		return bch_data_invalidate(cl);
 
+	if (atomic_sub_return(bio_sectors(bio), &op->c->sectors_to_gc) < 0)
+		wake_up_gc(op->c);
+
 	/*
 	 * Journal writes are marked REQ_FLUSH; if the original write was a
 	 * flush, it'll wait on the journal write.