linux-kernel - Re: [PATCH 27/35] sched/idle: Use explicit broadcast oneshot control function

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:	Sat, 21 Feb 2015 12:19:04 +0100
From:	Peter Zijlstra <peterz@...radead.org>
To:	Nicolas Pitre <nico@...aro.org>
Cc:	linux-kernel@...r.kernel.org, mingo@...nel.org, rjw@...ysocki.net,
	tglx@...utronix.de
Subject: Re: [PATCH 27/35] sched/idle: Use explicit broadcast oneshot control
 function

On Fri, Feb 20, 2015 at 07:56:17PM -0500, Nicolas Pitre wrote:
> On Mon, 16 Feb 2015, Peter Zijlstra wrote:
> 
> > From: Thomas Gleixner <tglx@...utronix.de>
> > 
> > Replace the clockevents_notify() call with an explicit function call.
> > 
> > Signed-off-by: Thomas Gleixner <tglx@...utronix.de>
> 
> This patch makes my test system hang solid after letting it sit idle for 
> 5 to 15 minutes.  Reverting it and this issue goes away.
> 
> The explicit function call is not an equivalent replacement. In 
> clockevents_notify() the clockevents_lock is held across the call to 
> tick_broadcast_enter() or tick_broadcast_exit(). This patch drops the 
> locking.

Yeah, the Changelog introducing the explicit call states as much. I'll
have to go figure out why that matters here.
--
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/