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Date: Tue, 22 Jan 2008 22:21:21 +0530
From: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Dave Young <hidave.darkstar@gmail.com>, linux-kernel@vger.kernel.org,
       mingo@elte.hu
Subject: Re: [PATCH] sched: don't take a mutex from interrupt context
Message-ID: <20080122165121.GE31049@linux.vnet.ibm.com>
Reply-To: vatsa@linux.vnet.ibm.com
References: <20080122023626.GA12213@darkstar.te-china.tietoenator.com> <1201019138.6341.24.camel@lappy>
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On Tue, Jan 22, 2008 at 05:25:38PM +0100, Peter Zijlstra wrote:
> @@ -1428,9 +1428,9 @@ static void print_cfs_stats(struct seq_f
>  #ifdef CONFIG_FAIR_GROUP_SCHED
>  	print_cfs_rq(m, cpu, &cpu_rq(cpu)->cfs);
>  #endif
> -	lock_task_group_list();
> +	rcu_read_lock();
>  	for_each_leaf_cfs_rq(cpu_rq(cpu), cfs_rq)
>  		print_cfs_rq(m, cpu, cfs_rq);

Isn't there a possibility that print_cfs_rq() can block?

> -	unlock_task_group_list();
> +	rcu_read_unlock();
>  }
>  #endif
> 

-- 
Regards,
vatsa