Messages in this thread | | | Subject | Re: [PATCH V3 0/5] bugs fix for large PEBS mmap read and rdpmc read | From | "Liang, Kan" <> | Date | Wed, 31 Jan 2018 10:15:33 -0500 |
| |
On 1/31/2018 8:15 AM, Jiri Olsa wrote: > On Wed, Jan 31, 2018 at 10:15:39AM +0100, Jiri Olsa wrote: >> On Tue, Jan 30, 2018 at 07:59:41PM -0800, Andi Kleen wrote: >>>> Still, the part I am missing here, is why asking for >>>> PERF_SAMPLE_PERIOD voids large PEBS. >>> >>> I think it was disabled together with frequency mode >>> (which we could support too, but it's a bit more work) >>> >>> But yes PERIOD could probably be allowed. >> >> looks like it's just a matter of adding PERF_SAMPLE_PERIOD >> into PEBS_FREERUNNING_FLAGS, we already populate period >> in setup_pebs_sample_data >> >> jirka >> >> >> --- >> diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h >> index 8e4ea143ed96..78f91ec1056e 100644 >> --- a/arch/x86/events/perf_event.h >> +++ b/arch/x86/events/perf_event.h >> @@ -93,7 +93,8 @@ struct amd_nb { >> PERF_SAMPLE_ID | PERF_SAMPLE_CPU | PERF_SAMPLE_STREAM_ID | \ >> PERF_SAMPLE_DATA_SRC | PERF_SAMPLE_IDENTIFIER | \ >> PERF_SAMPLE_TRANSACTION | PERF_SAMPLE_PHYS_ADDR | \ >> - PERF_SAMPLE_REGS_INTR | PERF_SAMPLE_REGS_USER) >> + PERF_SAMPLE_REGS_INTR | PERF_SAMPLE_REGS_USER | \ >> + PERF_SAMPLE_PERIOD) > > seems to work, getting large PEBS event for following command line: > > perf record -e cycles:P -c 100 --no-timestamp -C 0 --period > >
Yes, I tried the patch. The large PEBS can be enabled with the PERIOD flag. Everything looks good.
Jirka, could you please post the patch as well?
Thanks, Kan
| |