From 7278c9c19bd85cf33213a2e0b538a18d3ac8ad00 Mon Sep 17 00:00:00 2001
From: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
Date: Fri, 17 Dec 2010 08:57:14 +0100
Subject: [PATCH] cfq-iosched: don't check cfqg in choose_service_tree()

When cfq_choose_cfqg() is called in select_queue(), there must be at least one
backlogged CFQ queue waiting for dispatching, hence there must be at least one
backlogged CFQ group on service tree. So we never call choose_service_tree()
with cfqg == NULL.

Signed-off-by: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
---
Reading git-format-patch failed