hwpstate{_amd,intel}(4): Move common knobs to a separate file
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Authored by olce on Jan 5 2026, 3:23 PM.

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markj
khng
aokblast
emaste

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rG9a0a35916ab0: hwpstate{_amd,intel}(4): Move common knobs to a separate file
rG804329587508: hwpstate{_amd,intel}(4): Move common knobs to a separate file

Summary

This is to avoid conflict for 'machdep.hwpstate_pkg_ctrl' for the time
being (I expect to remove it for hwpstate_amd(4) at some point), but may
prove useful for other knobs, such as 'debug.hwpstate_verbose' (which is
currently not used in Intel's driver).

Fixes: 3e6e4e4a0d42 ("hwpstate: add CPPC support for pstate driver on AMD")

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rG FreeBSD src repository

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Event Timeline

aokblast created this revision.Jan 5 2026, 3:23 PM

Herald added a subscriber: imp. · View Herald TranscriptJan 5 2026, 3:23 PM

aokblast requested review of this revision.Jan 5 2026, 3:23 PM

Harbormaster completed remote builds in B69626: Diff 169067.Jan 5 2026, 3:23 PM

aokblast added reviewers: markj, olce, khng.Jan 5 2026, 3:23 PM

markj added inline comments.Jan 5 2026, 3:29 PM

sys/x86/cpufreq/hwpstate_amd.c
365	This definitely needs some comment explaining why we register the sysctls this way.

olce mentioned this in D49587: hwpstate: add CPPC support for pstate driver on AMD.Jan 5 2026, 3:50 PM

olce added inline comments.Jan 5 2026, 4:13 PM

sys/x86/cpufreq/hwpstate_amd.c
366–376	While it does not hurt per se, I would not move the above knobs here, as they do not exist in the Intel driver and my plan is to remove `machdep.hwpstate_pkg_ctrl` both here and in the Intel driver in favor of a common knob under `dev.hwpstate_*` to set all cores' EPP, which could later lead to removing `hwpstate_modevent()`.

cy added a subscriber: cy.Feb 3 2026, 3:26 PM

emaste added a subscriber: emaste.Feb 4 2026, 2:03 PM

olce mentioned this in D55139: cpufreq: Fix sysctl name conflict between hwpstate_intel and hwpstate_amd.Feb 6 2026, 9:16 AM

"Simpler" approach with some common file holding the common sysctl knobs. As said, I anticipate that machdep.hwpstate_pkg_ctrl will be removed from hwpstate_amd, but debug.hwpstate_verbose will probably stay and start to be used in hwpstate_intel as well. There are other knobs in hwpstate_amd that might become relevant for Intel too, but I haven't spent too much time on them, they could be moved later.

olce added a reviewer: emaste.Feb 6 2026, 11:02 AM

New approach

Harbormaster completed remote builds in B70466: Diff 171324.Feb 6 2026, 11:03 AM

olce added inline comments.Feb 6 2026, 11:04 AM

sys/sys/sysctl.h
38–40 ↗	(On Diff #171324)	Oops, that part to be committed separately (and could be changed if someone objects to including `sys/types.h` from `sys/sysctl.h`).