Message-ID: <1363696232.22553.37.camel@laptop>
Subject: Re: [PATCH V3 1/7] sched: Create sched_select_cpu() to give
 preferred CPU for power saving
From: Peter Zijlstra <peterz@infradead.org>
To: Viresh Kumar <viresh.kumar@linaro.org>
Cc: pjt@google.com, paul.mckenney@linaro.org, tglx@linutronix.de,
        tj@kernel.org, suresh.b.siddha@intel.com, venki@google.com,
        mingo@redhat.com, rostedt@goodmis.org, linaro-kernel@lists.linaro.org,
        robin.randhawa@arm.com, Steve.Bannister@arm.com, Liviu.Dudau@arm.com,
        charles.garcia-tobin@arm.com, Arvind.Chauhan@arm.com,
        linux-rt-users@vger.kernel.org, linux-kernel@vger.kernel.org
Date: Tue, 19 Mar 2013 13:30:32 +0100
In-Reply-To: <9f0fd16f792b9f9b399a4c91c98de37c56067d47.1363617402.git.viresh.kumar@linaro.org>
References: <cover.1363617402.git.viresh.kumar@linaro.org>
	 <9f0fd16f792b9f9b399a4c91c98de37c56067d47.1363617402.git.viresh.kumar@linaro.org>
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On Mon, 2013-03-18 at 20:53 +0530, Viresh Kumar wrote:
> +/*
> + * This routine returns the nearest non-idle cpu. It accepts a
> bitwise OR of
> + * SD_* flags present in linux/sched.h. If the local CPU isn't idle,
> it is
> + * returned back. If it is idle, then we must look for another CPU
> which have
> + * all the flags passed as argument as set.
> + */
> +int sched_select_cpu(unsigned int sd_flags)

So the only problem I have is that you expose the SD_flags to !sched
code. The only proposed user is in the workqueue code and passes 0.

Why not leave out the sd_flags argument and introduce it once you start
using it; at which point we can argue on the interface.

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