linux-kernel - Re: [PATCH V3 1/7] sched: Create sched_select_cpu() to give preferred CPU for power saving

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <1363696232.22553.37.camel@laptop>
Date:	Tue, 19 Mar 2013 13:30:32 +0100
From:	Peter Zijlstra <peterz@...radead.org>
To:	Viresh Kumar <viresh.kumar@...aro.org>
Cc:	pjt@...gle.com, paul.mckenney@...aro.org, tglx@...utronix.de,
	tj@...nel.org, suresh.b.siddha@...el.com, venki@...gle.com,
	mingo@...hat.com, rostedt@...dmis.org,
	linaro-kernel@...ts.linaro.org, robin.randhawa@....com,
	Steve.Bannister@....com, Liviu.Dudau@....com,
	charles.garcia-tobin@....com, Arvind.Chauhan@....com,
	linux-rt-users@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH V3 1/7] sched: Create sched_select_cpu() to give
 preferred CPU for power saving

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.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/