diff options
| author | Yaxiong Tian <tianyaxiong@kylinos.cn> | 2026-02-03 10:48:52 +0800 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2026-02-03 22:15:46 +0100 |
| commit | 1fedbb589448bee9f20bb2ed9c850d1d2cf9963c (patch) | |
| tree | 8622df5b11797a4118cd82dac0e1f22bfd3a3c46 | |
| parent | a554a25e66efea0b78fb3d24f4f19289e037c0dc (diff) | |
cpufreq: intel_pstate: Enable asym capacity only when CPU SMT is not possible
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: 929ebc93ccaa ("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>
| -rw-r--r-- | drivers/cpufreq/intel_pstate.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index ec4abe374573..1625ec2d0d06 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -1161,7 +1161,7 @@ static void hybrid_init_cpu_capacity_scaling(bool refresh) * the capacity of SMT threads is not deterministic even approximately, * do not do that when SMT is in use. */ - if (hwp_is_hybrid && !sched_smt_active() && arch_enable_hybrid_capacity_scale()) { + if (hwp_is_hybrid && !cpu_smt_possible() && arch_enable_hybrid_capacity_scale()) { hybrid_refresh_cpu_capacity_scaling(); /* * Disabling ITMT causes sched domains to be rebuilt to disable asym |