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Date: Tue, 11 Jan 2011 22:00:05 +0800
From: Yong Zhang <yong.zhang0@gmail.com>
To: Bharata B Rao <bharata@linux.vnet.ibm.com>
Cc: linux-kernel@vger.kernel.org, Mike Galbraith <efault@gmx.de>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>, Ingo Molnar <mingo@elte.hu>
Subject: Re: [PATCH -tip 1/2] [PATCH -tip 1/2] sched: Reinstate group names
 in /proc/sched_debug.
Message-ID: <20110111140005.GA6069@zhy>
Reply-To: Yong Zhang <yong.zhang0@gmail.com>
References: <20110111101040.GD4772@in.ibm.com>
 <20110111101153.GE4772@in.ibm.com>
 <20110111124658.GA4507@zhy>
 <20110111134244.GJ4772@in.ibm.com>
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On Tue, Jan 11, 2011 at 07:12:44PM +0530, Bharata B Rao wrote:
> The group name is generated in a global buffer which is protected by
> this lock. Earlier small sized local buffer (on stack) was used for
> this purpose which wasn't ideal. Also since we can be here from
> interrupt context, I wanted to avoid allocation too. Hence went for
> a global buffer protected by a lock.

Sounds good ;)

BTW, I guess we can also remove rcu_read_lock/unlock() in print_rt_stats()
and print_cfs_stats() with sched_debug_lock hold.

Thanks,
Yong