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Date: Tue, 11 Jan 2011 20:46:58 +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: <20110111124658.GA4507@zhy>
Reply-To: Yong Zhang <yong.zhang0@gmail.com>
References: <20110111101040.GD4772@in.ibm.com>
 <20110111101153.GE4772@in.ibm.com>
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On Tue, Jan 11, 2011 at 03:41:54PM +0530, Bharata B Rao wrote:
> sched: Reinstate group names in /proc/sched_debug.
> 
> Displaying of group names in /proc/sched_debug was dropped in autogroup
> patches. Add group names while displaying cfs_rq and tasks information.
> 
> Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
> ---
>  kernel/sched_debug.c |   35 +++++++++++++++++++++++++++++++++++
>  1 file changed, 35 insertions(+)
> 
> --- a/kernel/sched_debug.c
> +++ b/kernel/sched_debug.c
> @@ -16,6 +16,8 @@
>  #include <linux/kallsyms.h>
>  #include <linux/utsname.h>
>  
> +static DEFINE_SPINLOCK(sched_debug_lock);

I don't get your point on introducing this lock.
Just to avoid concurrent access?
Or could you explain please?

Thanks,
Yong