From: Milan Broz <mbroz@redhat.com>
Date: Wed, 2 Jul 2008 08:34:28 +0000 (+0100)
Subject: dm crypt: use cond_resched
X-Git-Tag: v2.6.26-rc9~81^2
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c7f1b2044191a82e7f0a1a674751ed582289e2e0;p=linux-2.6

dm crypt: use cond_resched

Add cond_resched() to prevent monopolising CPU when processing large bios.

dm-crypt processes encryption of bios in sector units.  If the bio request
is big it can spend a long time in the encryption call.

Signed-off-by: Milan Broz <mbroz@redhat.com>
Tested-by: Yan Li <elliot.li.tech@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
---

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 835def1141..ab6a61db63 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -432,6 +432,7 @@ static int crypt_convert(struct crypt_config *cc,
 		case 0:
 			atomic_dec(&ctx->pending);
 			ctx->sector++;
+			cond_resched();
 			continue;
 
 		/* error */