linux-kernel - Re: [PATCH] sched: Remove ACCESS

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: <alpine.DEB.2.02.1408121510310.26811@chino.kir.corp.google.com>
Date:	Tue, 12 Aug 2014 15:11:26 -0700 (PDT)
From:	David Rientjes <rientjes@...gle.com>
To:	Pranith Kumar <bobby.prani@...il.com>
cc:	Peter Zijlstra <peterz@...radead.org>,
	Ingo Molnar <mingo@...hat.com>,
	"open list:SCHEDULER" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] sched: Remove ACCESS_ONCE() for jiffies

On Tue, 12 Aug 2014, Pranith Kumar wrote:

> It looks more like an inconsistency. These are the only three places
> which use ACCESS_ONCE() for jiffies. Also, in doc/memory-barriers.txt,
> it explicitly states that ACCESS_ONCE(jiffies) is not necessary. I
> grepped for this usage after reading that document just to make sure
> and found these three uses.
> 
> But yes, there is no harm being done by using ACCESS_ONCE().
> 

One could argue that doing ACCESS_ONCE(jiffies) is always better because 
of the context it which it is used rather than qualifying jiffies itself 
as volatile.
--
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/