On Fri, Jan 19, 2018 at 03:15:00PM +0000, Liang, Kan wrote: > > > > On Thu, Jan 18, 2018 at 05:43:10PM +0000, Liang, Kan wrote: > > > In the uncore document, there is no event-code assigned to free running > > counters. > > > Some events need to be defined to indicate the free running counters. > > > The events are encoded as event-code + umask-code. > > > > > > The event-code for all free running counters is 0xff, which is the > > > same as the fixed counters. > > > > Is it possible to count the same things using the generic counters? > > > > Yes, there are events for generic counters to count bandwidth and > utilization. > > The reasons of introducing free running counters are > - To provide highly valuable information (bandwidth and utilization) > which most of the customers are interested in > - To save on the precious generic counters
_IF_ the exact same counters are available on the GPs then we must use the same event code for them and use event scheduling to place them on fixed/free-running counters when possible. That's what we do for the CPU PMU's fixed counters too. Don't invent magic event codes just because.
