diff options
| author | Beata Michalska <beata.michalska@arm.com> | 2025-02-20 09:10:15 +0000 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2025-02-21 09:37:52 +0000 |
| commit | 20711efa91e8ba44149f5e2ed1cf81e5355650e5 (patch) | |
| tree | 9a310fd36ba0fed18653b3fe4a926dc3f6ae04a4 | |
| parent | 39b19974982e03bd7b950f33bc0855385845c9fb (diff) | |
arm64: Utilize for_each_cpu_wrap for reference lookup
While searching for a reference CPU within a given policy,
arch_freq_get_on_cpu relies on cpumask_next_wrap to iterate over
all available CPUs and to ensure each is verified only once.
Recent changes to cpumask_next_wrap will handle the latter no more,
so switching to for_each_cpu_wrap, which preserves expected behavior
while ensuring compatibility with the updates.
Not to mention that when iterating over each CPU, using a dedicated
iterator is preferable to an open-coded loop.
Fixes: 16d1e27475f6 ("arm64: Provide an AMU-based version of arch_freq_get_on_cpu")
Signed-off-by: Beata Michalska <beata.michalska@arm.com>
Link: https://lore.kernel.org/r/20250220091015.2319901-1-beata.michalska@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| -rw-r--r-- | arch/arm64/kernel/topology.c | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c index a09b0551ec59..9e3583720668 100644 --- a/arch/arm64/kernel/topology.c +++ b/arch/arm64/kernel/topology.c @@ -254,7 +254,7 @@ int arch_freq_get_on_cpu(int cpu) if (!housekeeping_cpu(cpu, HK_TYPE_TICK) || time_is_before_jiffies(last_update + msecs_to_jiffies(AMU_SAMPLE_EXP_MS))) { struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); - int ref_cpu = cpu; + int ref_cpu; if (!policy) return -EINVAL; @@ -265,11 +265,15 @@ int arch_freq_get_on_cpu(int cpu) return -EOPNOTSUPP; } - do { - ref_cpu = cpumask_next_wrap(ref_cpu, policy->cpus, - start_cpu, true); - - } while (ref_cpu < nr_cpu_ids && idle_cpu(ref_cpu)); + for_each_cpu_wrap(ref_cpu, policy->cpus, cpu + 1) { + if (ref_cpu == start_cpu) { + /* Prevent verifying same CPU twice */ + ref_cpu = nr_cpu_ids; + break; + } + if (!idle_cpu(ref_cpu)) + break; + } cpufreq_cpu_put(policy); |