Page MenuHomeFreeBSD

hwpmc_arm64: fill kern.hwpmc.cpuid
ClosedPublic

Authored by mhorne on Jun 1 2021, 4:17 PM.
Tags
None
Referenced Files
F132388761: D30601.id90276.diff
Thu, Oct 16, 11:59 AM
F132356843: D30601.id.diff
Thu, Oct 16, 5:00 AM
Unknown Object (File)
Wed, Oct 15, 2:22 PM
Unknown Object (File)
Wed, Oct 15, 2:22 PM
Unknown Object (File)
Wed, Oct 15, 2:21 PM
Unknown Object (File)
Wed, Oct 15, 3:29 AM
Unknown Object (File)
Sep 2 2025, 2:23 PM
Unknown Object (File)
Aug 25 2025, 7:32 AM
Subscribers

Details

Summary

This will be used to detect supported pmu events. The expected format is
the MIDR register with the revision and variant fields masked. See
lib/libpmc/pmu-events/arch/arm64/mapfile.csv.

Diff Detail

Repository
rG FreeBSD src repository
Lint
Lint Not Applicable
Unit
Tests Not Applicable

Event Timeline

mhorne requested review of this revision.Jun 1 2021, 4:17 PM
sys/dev/hwpmc/hwpmc_arm64.c
522–523

Create kern.hwpmc.cpuid.0 etc. (one per CPU) and deprecate kern.hwpmc.cpuid?

sys/dev/hwpmc/hwpmc_arm64.c
522–523

I looked into this a bit, and tried to implement it. It is easy to provide on the kernel side, but the pmu bits in libpmc will need more significant work to plumb the notion of a desired CPU into all paths that invoke the sysctl.

I think it would be best to leave this as a TODO for a more concentrated effort at addressing big.LITTLE in libpmc/hwpmc.

Any further comments? I plan to commit within the next day or two if not.

This revision was not accepted when it landed; it landed in state Needs Review.Jun 30 2021, 7:49 PM
This revision was automatically updated to reflect the committed changes.