From: Peter Zijlstra <peterz@infradead.org>
To: Darren Hart <dvhltc@us.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>, "lkml," <linux-kernel@vger.kernel.org>
Subject: Re: Dynamically determine if kernel includes CFS Scheduler
Date: Fri, 06 Mar 2009 22:01:06 +0100 [thread overview]
Message-ID: <1236373266.6326.804.camel@laptop> (raw)
In-Reply-To: <49B18B2E.606@us.ibm.com>
On Fri, 2009-03-06 at 12:44 -0800, Darren Hart wrote:
> I've received an internal request for a means to determine at run-time
> if the CFS scheduler is included in the running kernel. Looking through
> the git commit log and the /proc/sys/kernel filesystem, I think I see
> two approaches:
>
> 1) stat("/proc/sys/kernel/sched_compat_yield")
> This confirms 2.6.23-rc7 kernel or later which definitely has the CFS
> scheduler and this functionality is of interest anyway.
> 2) Test if the kernel version is >= 2.6.22 which is where I believe CFS
> landed.
>
> Any guesses as to how robust/future-proof approach #1 would be?
The question is why? Relying on scheduler specifics outside of whatever
POSIX mandates is an application bug.
next prev parent reply other threads:[~2009-03-06 21:01 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-03-06 20:44 Dynamically determine if kernel includes CFS Scheduler Darren Hart
2009-03-06 21:01 ` Peter Zijlstra [this message]
2009-03-06 22:53 ` Sitsofe Wheeler
2009-03-06 23:01 ` Darren Hart
2009-03-06 23:08 ` Sitsofe Wheeler
2009-03-07 0:17 ` Darren Hart
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