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Update hwpmc on armv7 to handle overflow better

Authored by andrew on Jan 5 2021, 10:58 AM.



When testing hwpmc on arm64 we found the counter could overflow while
reading the event count. Handle this case in the armv7 code by also
checking if the overflow bit is set and incrementing the overflow
cound as needed.

Sponsored by: Innovate UK

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R10 FreeBSD src repository
Automatic diff as part of commit; lint not applicable.
Automatic diff as part of commit; unit tests not applicable.

Event Timeline

andrew created this revision.

Set the overflow when restoring register values. Start is just to start the counters counting.

This revision was not accepted when it landed; it landed in state Needs Review.Jan 8 2021, 2:30 PM
This revision was automatically updated to reflect the committed changes.