Date: Tue, 13 Feb 2007 13:46:25 +0530
From: Srivatsa Vaddagiri <vatsa@in.ibm.com>
To: "Paul Menage" <menage@google.com>
Cc: sekharan@us.ibm.com, ckrm-tech@lists.sourceforge.net,
       linux-kernel@vger.kernel.org, xemul@sw.ru, dev@sw.ru,
       containers@lists.osdl.org, pj@sgi.com, ebiederm@xmission.com,
       mbligh@google.com, winget@google.com, rohitseth@google.com,
       serue@us.ibm.com, devel@openvz.org
Subject: Re: [ckrm-tech] [PATCH 1/7] containers (V7): Generic container system abstracted from cpusets code
Message-ID: <20070213081625.GA4252@in.ibm.com>
Reply-To: vatsa@in.ibm.com
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On Tue, Feb 13, 2007 at 11:18:57AM +0530, Srivatsa Vaddagiri wrote:
> Which make me wonder why we need task_lock() at all ..I can understand
> the need for a lock like that if we are reading/updating multiple words
> in task_struct under the lock. In this case, it is used to read/write
> just one pointer, isnt it? I think it can be eliminated all-together
> with the use of RCU.

I see that cpuset.c uses task_lock to read/write multiple words
(cpuset_update_task_memory_state) ..So yes it is necessary in attach_task() ..


-- 
Regards,
vatsa
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