linux-kernel - Re: [RFC PATCH] Introduce timekeeper latch synchronization

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, 13 Sep 2013 09:31:56 +0200
From:	Peter Zijlstra <peterz@...radead.org>
To:	Mathieu Desnoyers <mathieu.desnoyers@...icios.com>
Cc:	"Paul E. McKenney" <paulmck@...ux.vnet.ibm.com>,
	John Stultz <john.stultz@...aro.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	Richard Cochran <richardcochran@...il.com>,
	Prarit Bhargava <prarit@...hat.com>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	Steven Rostedt <rostedt@...dmis.org>,
	Ingo Molnar <mingo@...e.hu>, linux-kernel@...r.kernel.org,
	lttng-dev@...ts.lttng.org
Subject: Re: [RFC PATCH] Introduce timekeeper latch synchronization

On Thu, Sep 12, 2013 at 10:52:53PM -0400, Mathieu Desnoyers wrote:
> OK! Here is the full implementation of the idea against Linux
> timekeeper, ntp, and PPS. It appears that ntp and PPS were relying on
> the timekeeper seqlock too. And guess what, after booting my laptop with
> this kernel there still no smoke coming out of it after a good 5 minutes
> of testing. ;-)
> 
> Comments are welcome.

I think that moving stuff into structures is a worthwhile change on its
own, but I'll leave John and Thomas to decide on all that.

The latch thing does make the update side slightly more expensive due to
having to do that copy every time, but ideally that wouldn't happen all
that often.
--
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/