On Thu, Jun 19, 2025 at 04:04:42PM +0200, Peter Zijlstra wrote: > On Thu, Jun 19, 2025 at 02:57:55PM +0100, Mark Rutland wrote: > > On Tue, Jun 17, 2025 at 12:36:18PM +0200, Peter Zijlstra wrote: > > > On Tue, Jun 17, 2025 at 07:27:50PM +0900, Koichi Okuno wrote: > > > > + pcipmu->pmu = (struct pmu) { > > > > + .parent = dev, > > > > + .task_ctx_nr = perf_invalid_context, > > > > + > > > > + .pmu_enable = fujitsu_pci__pmu_enable, > > > > + .pmu_disable = fujitsu_pci__pmu_disable, > > > > + .event_init = fujitsu_pci__event_init, > > > > + .add = fujitsu_pci__event_add, > > > > + .del = fujitsu_pci__event_del, > > > > + .start = fujitsu_pci__event_start, > > > > + .stop = fujitsu_pci__event_stop, > > > > + .read = fujitsu_pci__event_read, > > > > + > > > > + .attr_groups = fujitsu_pci_pmu_attr_grps, > > > > + .capabilities = PERF_PMU_CAP_NO_EXCLUDE, > > > > > > Should these drivers not also have PERF_PMU_CAP_NO_INTERRUPT ? Per them > > > being uncore they cannot generate samples. > > > > These PMUs actually have an interrupt, so that might be a bit confusing. > > That said, the counters seem to be 64-bit, so the interrupt doesn't seem > > practically necessary today. > > Yeah, I saw they had an interrupt. But them being uncore they must not > sample, and NO_INTERRUPT means not being able to sample. > > Naming urgh :-) Yeah :) FWIW, that came to mind due to: https://lore.kernel.org/lkml/20250618-perf-pmu-cap-docs-v1-1-0d34387d6e47@xxxxxxxxxxxxx/ ... and if NO_INTERRUPT would be better-named as NO_SAMPLING, that might be a good opportunity to clean that up. > > Either way, the fujitsu_pci__event_init() function rejects sampling > > events, so it correctly rejects sampling events. > > > > IMO, it'd be a bit nicer to do the inverse, and have the perf core > > reject sampling events by default for non-CPU PMUs. > > Yeah, there's lots of cleanup to be done. Quite possibly also some > unification between the various drivers. > > Just need someone that knows what they're doing that has spare time, > know anybody like that? :-) I think a few folk likle that live in the nearest hall of mirrors... If you're happy with that in concept, I can see about getting someone to look at that -- the general idea has come up a few times. Mark.