Re: [PATCH 2/8] vtime: Use consistent clocks among nohz accounting

[Frederic Weisbecker <fweisbec@gmail.com>]

On Mon, Jun 03, 2013 at 11:47:17AM +0200, Stefan Seyfried wrote:
> Am 20.05.2013 18:01, schrieb Frederic Weisbecker:
> > While computing the cputime delta of dynticks CPUs,
> > we are mixing up clocks of differents natures:
> 
> [...]
> 
> > As a consequence, some strange behaviour with unstable tsc
> > has been observed such as non progressing constant zero cputime.
> > (The 'top' command showing no load).
> 
> This happens for example on my trusty ThinkPad X200s (family 6 model 23
> stepping 10 Core 2 duo), seriously confusing its user (me :-).
> 
> > Fix this by only using local_clock(), or its irq safe/remote
> > equivalent, in vtime code.
> > 
> > Reported-by: Mike Galbraith <efault@gmx.de>
> > Suggested-by: Mike Galbraith <efault@gmx.de>
> > Cc: Steven Rostedt <rostedt@goodmis.org>
> > Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
> > Cc: Ingo Molnar <mingo@kernel.org>
> > Cc: Thomas Gleixner <tglx@linutronix.de>
> > Cc: Peter Zijlstra <peterz@infradead.org>
> > Cc: Borislav Petkov <bp@alien8.de>
> > Cc: Li Zhong <zhong@linux.vnet.ibm.com>
> > Cc: Mike Galbraith <efault@gmx.de>
> > Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
> 
> FWIW:
> Tested-by: Stefan Seyfried <seife+dev@b1-systems.com>
> 
> This patch fixes the 0% CPU issue on openSUSE Factory kernels for me.

Thanks! The patch has been committed already so I can't add your Tested-by:
but feedbacks on testing are always appeciated.