From: Dave Kleikamp <dave.kleikamp@oracle.com>
Date: Tue, 24 Apr 2012 22:43:47 +0000 (-0500)
Subject: loop: loop_thread needs to set the PF_LESS_THROTTLE flag
X-Git-Tag: v2.6.39-400.9.0~426^2~7^2
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=b67ffdd0b198da23a53ffb5a2f58b673cd9159eb;p=users%2Fjedix%2Flinux-maple.git

loop: loop_thread needs to set the PF_LESS_THROTTLE flag

The underlying file system may call balance_dirty_pages. We don't want
it to throttle there since we may be in the process of writing dirty
pages. This patch addresses the problem in the same manner as a local
nfs mount, as nfsd does the same.

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
---

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index d22ddcd69630..0198e259cfdb 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -623,6 +623,8 @@ static int loop_thread(void *data)
 	struct loop_device *lo = data;
 	struct bio *bio;
 
+	current->flags |= PF_LESS_THROTTLE;
+
 	set_user_nice(current, -20);
 
 	while (!kthread_should_stop() || !bio_list_empty(&lo->lo_bio_list)) {