linux-kernel - Re: [PATCH 1/2] sched/nohz: add sysctl control over sched_tick_max

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: <20130619184238.GD21522@somewhere.redhat.com>
Date:	Wed, 19 Jun 2013 20:42:40 +0200
From:	Frederic Weisbecker <fweisbec@...il.com>
To:	Kevin Hilman <khilman@...aro.org>
Cc:	linaro-kernel@...ts.linaro.org, Ingo Molnar <mingo@...hat.com>,
	Peter Zijlstra <peterz@...radead.org>,
	Clark Williams <clark.williams@...il.com>,
	Tony Luck <tony.luck@...el.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Kees Cook <keescook@...omium.org>,
	Mel Gorman <mgorman@...e.de>, Rik van Riel <riel@...hat.com>,
	open list <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 1/2] sched/nohz: add sysctl control over
 sched_tick_max_deferment

On Tue, Jun 18, 2013 at 04:58:28PM -0700, Kevin Hilman wrote:
> Allow sysctl override of sched_tick_max_deferment in order to ease
> finding/fixing the remaining issues with full nohz.
> 
> The value to be written is in jiffies, and -1 means the max deferment
> is disabled (scheduler_tick_max_deferment() returns KTIME_MAX.)
> 
> Cc: Frederic Weisbecker <fweisbec@...il.com>
> Signed-off-by: Kevin Hilman <khilman@...aro.org>

This looks like a useful thing but I wonder if a debugfs file would
be more appropriate than sysctl.

The scheduler tick max deferment is supposed to be a temporary
hack so we probably don't want to bring a real user ABI for that.

I believe sysctl is for permanent ABIs, right?
--
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/