From mboxrd@z Thu Jan 1 00:00:00 1970 From: Li Zefan Subject: Re: [PATCH] [RT] avoid preemption in memory controller code Date: Tue, 09 Dec 2008 09:13:12 +0800 Message-ID: <493DC628.5060900@cn.fujitsu.com> References: <1228746854-23875-1-git-send-email-tim@klingt.org> Mime-Version: 1.0 Content-Type: text/plain; charset=GB2312 Content-Transfer-Encoding: 7bit Cc: rostedt@goodmis.org, linux-rt-users@vger.kernel.org, linux-kernel@vger.kernel.org, Balbir Singh , KAMEZAWA Hiroyuki To: Tim Blechmann Return-path: Received: from cn.fujitsu.com ([222.73.24.84]:56044 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1753187AbYLIBOp (ORCPT ); Mon, 8 Dec 2008 20:14:45 -0500 In-Reply-To: <1228746854-23875-1-git-send-email-tim@klingt.org> Sender: linux-rt-users-owner@vger.kernel.org List-ID: CC: Balbir Singh CC: KAMEZAWA Hiroyuki Tim Blechmann wrote: > the lru_lock of struct mem_group_per_zone is used to avoid preemption > during the __mem_cgroup_stat_add_safe function. > therefore, a raw_spinlock_t should be used. > FYI, this lru_lock no longer exists in -mm tree. The following patch removes that lock: http://marc.info/?l=linux-mm&m=122665814801979&w=2 > Signed-off-by: Tim Blechmann > --- > mm/memcontrol.c | 4 ++-- > 1 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index 517f945..8661732 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -95,9 +95,9 @@ enum mem_cgroup_zstat_index { > > struct mem_cgroup_per_zone { > /* > - * spin_lock to protect the per cgroup LRU > + * raw_spin_lock to protect the per cgroup LRU > */ > - spinlock_t lru_lock; > + raw_spinlock_t lru_lock; > struct list_head active_list; > struct list_head inactive_list; > unsigned long count[NR_MEM_CGROUP_ZSTAT];