On Thu, Oct 20, 2016 at 01:23:51PM +0200, Jan Glauber wrote: > On Thu, Oct 20, 2016 at 12:37:07PM +0200, Peter Zijlstra wrote: > > On Thu, Oct 20, 2016 at 11:30:36AM +0200, Jan Glauber wrote: > > > Note: > > > I'm using perf_sw_context in difference to perf_invalid_context > > > (see WARN_ON in perf_pmu_register). Reason is that with > > > perf_invalid_context > > > add() is never called and the counter results are shown as "unsupported" > > > by > > > perf. With perf_sw_context everything works as expected. > > > > What?! All the uncore PMUs use perf_invalid_context. What doesn't work > > for you? > > OK, so using perf_invalid_context and "-a" seems to work. > > But I must say that I hate that from a user perspective. The user needs to > know about > the type of PMU behind the event and then provide "-a" or get a "<not > supported" > as counter value?
Sure, but in the interest of getting *something* merged, can we start off using perf_invalid_context and then have the discussion about whether or not this can be extended later on, please? If your PMU is a shared resource amongst CPUs, it maybe that all you want is a better error message from the perf tool (but again, this can come later!). Will

