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Subjectperf: rdpmc and PERF_EVENT_IOC_RESET
Hello

so using rdpmc() and the mmap page to do fast perf_event reads seems to
interact poorly with the PERF_EVENT_IOC_RESET ioctl.

From what I can tell, on reset event->count is set to zero, but
event->hw.prev_count is not, so the userpg->offset field ends up negative
and weird things happen.

Shout reset just not be called if you are using the rdpmc() interface?

Vince


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