Messages in this thread | | | Date | Wed, 24 Jun 2009 19:47:34 +0200 | From | Ingo Molnar <> | Subject | Re: [patch 0/2] NOHZ vs. profile/oprofile v2 |
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* Martin Schwidefsky <schwidefsky@de.ibm.com> wrote:
> On Mon, 22 Jun 2009 17:40:30 +0200 > Ingo Molnar <mingo@elte.hu> wrote: > > > > > * Martin Schwidefsky <schwidefsky@de.ibm.com> wrote: > > > > > On Mon, 22 Jun 2009 17:29:37 +0200 > > > Ingo Molnar <mingo@elte.hu> wrote: > > > > > > > > > > > * Martin Schwidefsky <schwidefsky@de.ibm.com> wrote: > > > > > > > > > [...] And if we really want to keep things separate there will be > > > > > two sets of per-cpu hrtimer, one for the old style profiler and > > > > > one for oprofile. Any preference for the user space interface to > > > > > set the sample rate? A sysctl? > > > > > > > > I dont think we want to keep things separate. Regarding old-style > > > > profiler, does anyone still use it? There's now a superior in-tree > > > > replacement for it, so we could phase it out. > > > > > > Well, for my part I won't miss it. But to be able to remove the > > > profile_tick() calls from the architectures I either have to rip > > > out the old profiler now, or adapt it to use hrtimer as well. > > > > Do we _have to_ touch it so widely right now? We could start with a > > deprecation warning in this cycle. Once it's deprecated we can > > remove all those calls. > > First version of the hrtimer patch for oprofile. I did not add the > sysctl yet, if the sysctl is added in oprofile_timer_init it would > not be available if some better profiling source is available. If > it is added unconditionally it would only have an effect if the > timer fallback is used. Both cases are not exactly nice for a user > space interface.
looks quite sane. I've Cc:-ed Robert.
Ingo
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