Re: [PATCH] time: Add locking to xtime access in get_seconds()

john stultz
2011-05-04T23:06:05Z

On Wed, 2011-05-04 at 09:51 -0700, Max Asbock wrote:
> On Tue, 2011-05-03 at 20:11 -0700, John Stultz wrote:
> > From: John Stultz <johnstul@us.ibm.com>
> >
> > So get_seconds() has always been lock free, with the assumption
> > that accessing a long will be atomic.
> >
>
> get_seconds() is used in the x86 machine check handler and there is a
> comment saying:
> /* We hope get_seconds stays lockless */
>
> This needs to be carefully looked at if locking is introduced to
> get_seconds().

Ah. Thanks for pointing this out Max.

I'll go ahead and use Andi's suggestion of the rmb();

Patch soon to follow.

thanks
-john