linux-kernel - Re: sched: Avoid SMT siblings in select_idle

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]

Date:	Fri, 18 Nov 2011 16:12:21 +0100
From:	Peter Zijlstra <peterz@...radead.org>
To:	Suresh Siddha <suresh.b.siddha@...el.com>
Cc:	Mike Galbraith <efault@....de>,
	linux-kernel <linux-kernel@...r.kernel.org>,
	Ingo Molnar <mingo@...e.hu>, Paul Turner <pjt@...gle.com>
Subject: Re: sched: Avoid SMT siblings in select_idle_sibling() if possible

On Thu, 2011-11-17 at 11:08 -0800, Suresh Siddha wrote:
> 
> From: Suresh Siddha <suresh.b.siddha@...el.com>
> Subject: sched: cleanup domain traversal in select_idle_sibling
> 
> Instead of going through the scheduler domain hierarchy multiple times
> (for giving priority to an idle core over an idle SMT sibling in a busy
> core), start with the highest scheduler domain with the SD_SHARE_PKG_RESOURCES
> flag and traverse the domain hierarchy down till we find an idle group.
> 
> This cleanup also addresses an issue reported by Mike where the recent
> changes returned the busy thread even in the presence of an idle SMT
> sibling in single socket platforms.
> 
> Signed-off-by: Suresh Siddha <suresh.b.siddha@...el.com>
> Cc: Mike Galbraith <efault@....de> 

Thanks Suresh!
--
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/