lkml.org 
[lkml]   [2011]   [Apr]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] perf: Allow set output buffer for tasks in the same thread group
Em Mon, Apr 25, 2011 at 09:40:38PM +0800, Lin Ming escreveu:
> On Mon, 2011-04-25 at 01:05 +0800, Peter Zijlstra wrote:
> > On Sun, 2011-04-24 at 22:57 +0800, Lin Ming wrote:
> > > Currently, kernel only allows an event to redirect its output to other
> > > events of the same task.
> > >
> > > This causes PERF_EVENT_IOC_SET_OUTPUT ioctl fails when an event is
> > > trying to redirect its output to other events in the same thread group.
> >
> > Which is exactly what it should do, you should never be allowed to
> > redirect your events to that of another task, since that other task
> > might be running on another CPU.
> >
> > The buffer code strictly assumes no concurrency, therefore its either
> > one task or one CPU.
>
> Well, this is not the right fix, then the perf tool code need to be
> fixed.

Yes, I'm working on it.

- Arnaldo


\
 
 \ /
  Last update: 2011-04-25 17:31    [W:0.355 / U:0.436 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site