linux-kernel - Re: lots of brief rcu stalls.

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:	Wed, 4 Dec 2013 18:43:55 -0800
From:	"Paul E. McKenney" <paulmck@...ux.vnet.ibm.com>
To:	Eric Dumazet <eric.dumazet@...il.com>
Cc:	Dave Jones <davej@...hat.com>,
	Linux Kernel <linux-kernel@...r.kernel.org>
Subject: Re: lots of brief rcu stalls.

On Wed, Dec 04, 2013 at 06:18:30PM -0800, Eric Dumazet wrote:
> On Wed, 2013-12-04 at 16:16 -0800, Paul E. McKenney wrote:
> > +	if (rdp->rsp == rcu_state &&
> > +	    ULONG_CMP_GE(ACCESS_ONCE(jiffies), rdp->rsp->jiffies_resched)) {
> > +		rdp->rsp->jiffies_resched += 5;
> > +		resched_cpu(rdp->cpu);
> > +	}
> > +
> >  	return 0;
> >  }
> 
> jiffies should not need ACCESS_ONCE(), right ?
> 
> It is one of the few variables marked with volatile keyword.

Good point!  I have queued a patch fixing this and four other occurrences
with your Submitted-by.

							Thanx, Paul

--
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/