Hi, On Fri, 27 Jul 2012 14:45:38 +0200, Jiri Olsa wrote: > On Fri, Jul 27, 2012 at 01:56:36PM +0200, Frederic Weisbecker wrote: >> The problem is more general than that I think. >> We need to be able to define finer grained contexts than just >> "task" and/or "CPU". >> >> And reusing events themselves would be a nice interface. >> >> For example create 3 events: >> >> A = irq entry tracepoint >> B = irq exit tracepoint >> C = cpu-cycles >> >> And say: I want to count cpu-cycles when event A fires and stop counting >> when B fires. >> >> With that you can count cpu cycles on irqs. >> >> You could use any event you want to define your contexts: lock, functions, >> etc... >> >> And even uprobes to define areas in userspace to profile. Would that solve >> the initial problem in the thread? Like hook on function library entry/exit? >> >> I talked about that to Jiri Olsa several times. May be he would be interested >> in implementing this. I posted some patchets one year ago but got >> sidetracked. >> >> This can give you an idea from where we can start: >> https://lkml.org/lkml/2011/3/14/346 >> >> Jiri, would you be interested in working on this? > > yep, I remember also talking about A/B being functions entry/exit > > I think that was also the initial push for having ftrace perf events > support, which already got in. > > I'll check ;) >
Very cool. :) I'm also interested in the feature although my background knowledge is not firm enough yet. Please let me know if there's anything I can help you on this. Thanks, Namhyung -- To unsubscribe from this list: send the line "unsubscribe linux-perf-users" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
