rpms/kernel/F-11 linux-2.6-cfq-choose-new-next-req.patch, NONE, 1.1 kernel.spec, 1.1742, 1.1743

[Chuck Ebbert]

Author: cebbert

Update of /cvs/pkgs/rpms/kernel/F-11
In directory cvs1.fedora.phx.redhat.com:/tmp/cvs-serv7832

Modified Files:
	kernel.spec 
Added Files:
	linux-2.6-cfq-choose-new-next-req.patch 
Log Message:
Fix serious CFQ performance regression.

linux-2.6-cfq-choose-new-next-req.patch:
 cfq-iosched.c |    1 +
 1 file changed, 1 insertion(+)

--- NEW FILE linux-2.6-cfq-choose-new-next-req.patch ---
From: Jeff Moyer <jmoyer at redhat.com>
Date: Fri, 11 Sep 2009 15:08:59 +0000 (+0200)
Subject: cfq: choose a new next_req when a request is dispatched
X-Git-Url: http://git.kernel.org/?p=linux%2Fkernel%2Fgit%2Ftorvalds%2Flinux-2.6.git;a=commitdiff_plain;h=06d2188644c85c56d243efab914f368d1d23c4a3

cfq: choose a new next_req when a request is dispatched

This patch addresses http://bugzilla.kernel.org/show_bug.cgi?id=13401, a
regression introduced in 2.6.30.

>From the bug report:

Signed-off-by: Jens Axboe <jens.axboe at oracle.com>
---

diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index a34686f..0e3814b 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -1110,6 +1110,7 @@ static void cfq_dispatch_insert(struct request_queue *q, struct request *rq)
 
 	cfq_log_cfqq(cfqd, cfqq, "dispatch_insert");
 
+	cfqq->next_rq = cfq_find_next_rq(cfqd, cfqq, rq);
 	cfq_remove_request(rq);
 	cfqq->dispatched++;
 	elv_dispatch_sort(q, rq);


Index: kernel.spec
===================================================================
RCS file: /cvs/pkgs/rpms/kernel/F-11/kernel.spec,v
retrieving revision 1.1742
retrieving revision 1.1743
diff -u -p -r1.1742 -r1.1743
--- kernel.spec	25 Sep 2009 05:46:42 -0000	1.1742
+++ kernel.spec	25 Sep 2009 07:59:50 -0000	1.1743
@@ -748,6 +748,9 @@ Patch14101: linux-2.6-cpufreq-cleanup-lo
 # fix hostap (#522269)
 Patch14200: hostap-revert-toxic-part-of-conversion.patch
 
+# fix cfq performance regression in 2.6.30
+Patch14300: linux-2.6-cfq-choose-new-next-req.patch
+
 %endif
 
 BuildRoot: %{_tmppath}/kernel-%{KVERREL}-root
@@ -1392,6 +1395,9 @@ ApplyPatch linux-2.6-cpufreq-cleanup-loc
 # fix hostap driver (#522269)
 ApplyPatch hostap-revert-toxic-part-of-conversion.patch
 
+# fix cfq performance regression in 2.6.30
+ApplyPatch linux-2.6-cfq-choose-new-next-req.patch
+
 # END OF PATCH APPLICATIONS
 
 %endif
@@ -1980,6 +1986,9 @@ fi
 # and build.
 
 %changelog
+* Fri Sep 25 2009 Chuck Ebbert <cebbert at redhat.com> 2.6.30.8-64
+- Fix serious CFQ performance regression.
+
 * Fri Sep 25 2009 Chuck Ebbert <cebbert at redhat.com> 2.6.30.8-63
 - Disable the GEM graphics manager on i686 PAE kernels
   (fixes modesetting on Intel graphics.)