Messages in this thread | | | From | "Liang, Kan" <> | Subject | RE: [PATCH V5 4/8] perf/x86/intel/uncore: add new data structures for free running counters | Date | Wed, 24 Jan 2018 15:46:49 +0000 |
| |
> On Tue, Jan 23, 2018 at 10:00:58PM +0000, Liang, Kan wrote: > > > On Fri, Jan 19, 2018 at 12:24:17PM -0800, Andi Kleen wrote: > > > > > Oh, think a bit more. > > > > > I think we cannot do the same thing as we did for CPU PMU's fixed > > > counters. > > > > > > > > > > The counters here are free running counters. They cannot be > start/stop. > > > > > > > > Yes free running counter have completely different semantics. They > > > > need a separate event code. > > > > > > The only thing that matters is if they count the same thing or not. > > > > > > > Hi Peter, > > > > There is NO event available on the GPs, that is exactly the same as > > the free-running counters. > > > > For example, the BW free-running counters count the requests associated > > with writes and completions. > > The most similar events on the GPs are DATA_REQ_{OF,BY}_CPU.* events. > > Except that some of their sub-events count requests which not completions. > > There are also other minor differences. > > So we don't have alternative events for the free-running counters. > > I think we have to use 0xff. > > OK, but explicitly mention this as the reason for having to invent event > codes. Them being fixed purpose or free running isn't a valid reason for > that.
Sure, I will add it in V6.
Thanks, Kan
| |