On Thu, May 09, 2013 at 05:20:22PM +0200, Jiri Olsa wrote: > On Thu, May 09, 2013 at 05:07:44PM +0200, Peter Zijlstra wrote: > > On Thu, May 09, 2013 at 03:32:15PM +0200, Jiri Olsa wrote: > > > hi, > > > adding sysfs attribute to specify the maximum allowed value > > > for perf_event_attr::precise_ip field. > > > > > > Adding functionality for simple 'p' modifier and 'precise' term > > > to get the maximum allowed value for perf_event_attr::precise_ip > > > field. > > > > > > > You've seem to lost the part explaining why we want this.. :-) > > well, initially it was an answer when we broke precise event > monitoring in kernel so I wrote automated test for it (patches 1,2,3) > https://lkml.org/lkml/2012/12/12/561
But those don't rely on the max thing right? > having maximum precise enabled with just single 'p' seemed > like good idea Doesn't seem like to me; that takes away the possibility to use less. > next step would be to enable precise automatically for 'cycles' > (when PEBS is working) asked for by Ingo > http://marc.info/?l=linux-kernel&m=135929050803963&w=2 Hurm.. I'm of two minds there. As Stephane has been pointing out for ages, cycles behaves significantly different between regular and PEBS events for some cases. Also, you really don't need the max_precise for that either. At worst you'll have a number of unsuccessful event creations. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
