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Date: Mon, 27 Feb 2006 16:16:34 +0530
From: Balbir Singh <balbir@in.ibm.com>
To: Ingo Molnar <mingo@elte.hu>
Cc: Shailabh Nagar <nagar@watson.ibm.com>,
       linux-kernel <linux-kernel@vger.kernel.org>,
       lse-tech <lse-tech@lists.sourceforge.net>
Subject: Re: [Lse-tech] Re: [Patch 2/7] Add sysctl for schedstats
Message-ID: <20060227104634.GB22492@in.ibm.com>
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<snip>
> why not just introduce a schedstats_lock mutex, and acquire it for both 
> the 'if (schedstats_sysctl)' line and the schedstats_set() line. That 
> will make the locking meaningful: two parallel sysctl ops will be atomic 
> to each other. [right now they wont be and they can clear schedstat data 
> in parallel -> not a big problem but it makes schedstats_lock rather 
> meaningless]
>

Ingo,

Can sysctl's run in parallel? sys_sysctl() is protects the call
to do_sysctl() with BKL (lock_kernel/unlock_kernel).

Am I missing something?

Balbir
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