diff options
Diffstat (limited to 'kernel/sched/cpufreq.c')
| -rw-r--r-- | kernel/sched/cpufreq.c | 22 |
1 files changed, 19 insertions, 3 deletions
diff --git a/kernel/sched/cpufreq.c b/kernel/sched/cpufreq.c index 22bd8980f32f..742fb9e62e1a 100644 --- a/kernel/sched/cpufreq.c +++ b/kernel/sched/cpufreq.c @@ -7,7 +7,7 @@ */ #include "sched.h" -DEFINE_PER_CPU(struct update_util_data *, cpufreq_update_util_data); +DEFINE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data); /** * cpufreq_add_update_util_hook - Populate the CPU's update_util_data pointer. @@ -48,8 +48,8 @@ EXPORT_SYMBOL_GPL(cpufreq_add_update_util_hook); * * Clear the update_util_data pointer for the given CPU. * - * Callers must use RCU-sched callbacks to free any memory that might be - * accessed via the old update_util_data pointer or invoke synchronize_sched() + * Callers must use RCU callbacks to free any memory that might be + * accessed via the old update_util_data pointer or invoke synchronize_rcu() * right after this function to avoid use-after-free. */ void cpufreq_remove_update_util_hook(int cpu) @@ -57,3 +57,19 @@ void cpufreq_remove_update_util_hook(int cpu) rcu_assign_pointer(per_cpu(cpufreq_update_util_data, cpu), NULL); } EXPORT_SYMBOL_GPL(cpufreq_remove_update_util_hook); + +/** + * cpufreq_this_cpu_can_update - Check if cpufreq policy can be updated. + * @policy: cpufreq policy to check. + * + * Return 'true' if: + * - the local and remote CPUs share @policy, + * - dvfs_possible_from_any_cpu is set in @policy and the local CPU is not going + * offline (in which case it is not expected to run cpufreq updates any more). + */ +bool cpufreq_this_cpu_can_update(struct cpufreq_policy *policy) +{ + return cpumask_test_cpu(smp_processor_id(), policy->cpus) || + (policy->dvfs_possible_from_any_cpu && + rcu_dereference_sched(*this_cpu_ptr(&cpufreq_update_util_data))); +} |