diff options
| -rw-r--r-- | drivers/cpufreq/cpufreq.c | 14 | ||||
| -rw-r--r-- | include/linux/cpufreq.h | 1 |
2 files changed, 15 insertions, 0 deletions
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index d976e22..03b3b69 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -312,6 +312,12 @@ static void __cpufreq_notify_transition(struct cpufreq_policy *policy, switch (state) { case CPUFREQ_PRECHANGE: + if (WARN(policy->transition_ongoing, + "In middle of another frequency transition\n")) + return; + + policy->transition_ongoing = true; + /* detect if the driver reported a value as "old frequency" * which is not equal to what the cpufreq core thinks is * "old frequency". @@ -331,6 +337,12 @@ static void __cpufreq_notify_transition(struct cpufreq_policy *policy, break; case CPUFREQ_POSTCHANGE: + if (WARN(!policy->transition_ongoing, + "No frequency transition in progress\n")) + return; + + policy->transition_ongoing = false; + adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); pr_debug("FREQ: %lu - CPU: %lu", (unsigned long)freqs->new, (unsigned long)freqs->cpu); @@ -1539,6 +1551,8 @@ int __cpufreq_driver_target(struct cpufreq_policy *policy, if (cpufreq_disabled()) return -ENODEV; + if (policy->transition_ongoing) + return -EBUSY; /* Make sure that target_freq is within supported range */ if (target_freq > policy->max) diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index 3c7ee2f..c0bc737 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -119,6 +119,7 @@ struct cpufreq_policy { struct kobject kobj; struct completion kobj_unregister; + bool transition_ongoing; /* Tracks transition status */ }; #define CPUFREQ_ADJUST (0) |
