cpufreq: intel_pstate: Enable asym capacity only when CPU SMT is not possible

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[ Upstream commit 1fedbb5894 ]

According to the description in the intel_pstate.rst documentation,
Capacity-Aware Scheduling and Energy-Aware Scheduling are only
supported on a hybrid processor without SMT. Previously, the system
used sched_smt_active() for judgment, which is not a strict condition
because users can switch it on or off via /sys at any time.

This could lead to incorrect driver settings in certain scenarios.
For example, on a CPU that supports SMT, a user can disable SMT
via the nosmt parameter to enable asym capacity, and then re-enable
SMT via /sys. In such cases, some settings in the driver would no
longer be correct.

To address this issue, replace sched_smt_active() with cpu_smt_possible(),
and only enable asym capacity when CPU SMT is not possible.

Fixes: 929ebc93cc ("cpufreq: intel_pstate: Set asymmetric CPU capacity on hybrid systems")
Signed-off-by: Yaxiong Tian <tianyaxiong@kylinos.cn>
[ rjw: Subject and changelog edits ]
Link: https://patch.msgid.link/20260203024852.301066-1-tianyaxiong@kylinos.cn
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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Yaxiong Tian 2026-02-03 10:48:52 +08:00 • committed by Sasha Levin

parent 26bec96bc5

commit 73caf86fe9

1 changed files with 1 additions and 1 deletions

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drivers/cpufreq/intel_pstate.c

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