From: Mike Snitzer <snitzer@redhat.com>
Date: Sat, 22 Mar 2014 17:45:46 +0000 (-0400)
Subject: dm thin: use on-stack plugging when submitting bios in process_thin_deferred_bios
X-Git-Url: https://git.fsl.cs.stonybrook.edu/?a=commitdiff_plain;h=0fcceac892d7ff529cc43045bd4f81bc2bb4791b;p=linux-dmdedup.git

dm thin: use on-stack plugging when submitting bios in process_thin_deferred_bios
---

diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index c5e098b316b..1b853d57f4a 100644
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -1440,6 +1440,7 @@ static void process_thin_deferred_bios(struct thin_c *tc)
 	unsigned long flags;
 	struct bio *bio;
 	struct bio_list bios;
+	struct blk_plug plug;
 
 	if (tc->requeue_mode) {
 		requeue_bio_list(tc, &tc->deferred_bio_list);
@@ -1466,6 +1467,7 @@ static void process_thin_deferred_bios(struct thin_c *tc)
 
 	spin_unlock_irqrestore(&tc->lock, flags);
 
+	blk_start_plug(&plug);
 	while ((bio = bio_list_pop(&bios))) {
 		/*
 		 * If we've got no free new_mapping structs, and processing
@@ -1484,6 +1486,7 @@ static void process_thin_deferred_bios(struct thin_c *tc)
 		else
 			pool->process_bio(tc, bio);
 	}
+	blk_finish_plug(&plug);
 }
 
 static void process_deferred_bios(struct pool *pool)