lkml.org 
[lkml]   [2013]   [Dec]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: 50 Watt idle power regression bisected to Linux-3.10

* Peter Zijlstra <peterz@infradead.org> wrote:

> On Wed, Dec 11, 2013 at 04:09:11PM +0100, Ingo Molnar wrote:
> >
> > * Thomas Gleixner <tglx@linutronix.de> wrote:
> >
> > > On Wed, 11 Dec 2013, Ingo Molnar wrote:
> > > >
> > > > Another thing that is required I think is to issue a write barrier
> > > > before CLFLUSH instruction. By my (possibly incorrect ...) reading of
> > > > the documentation CLFLUSH does not appear to be ordered (at all), so
> > > > it might execute before the modification to the affected memory?
> > >
> > > We already have a write barrier in the code which modifies
> > > current_thread_info()->flags.
> >
> > Which code is that, could you please cite it? (I tried finding it but
> > my grep-fu failed me.)
>
> current_set_polling_and_test().

Thx, those variants have the right barrier indeed.

Thanks,

Ingo


\
 
 \ /
  Last update: 2013-12-11 19:01    [W:0.277 / U:0.880 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site