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Date: Wed, 12 Jan 2011 13:19:30 +0530
From: Bharata B Rao <bharata@linux.vnet.ibm.com>
To: Yong Zhang <yong.zhang0@gmail.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.
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On Tue, Jan 11, 2011 at 10:00:05PM +0800, Yong Zhang wrote:
> 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.

We could, but I guess its not a recommended practice anymore to depend on
spinlocks to protect rcu readside.

Regards,
Bharata.