diff options
Diffstat (limited to 'include/linux/cpufreq.h')
| -rw-r--r-- | include/linux/cpufreq.h | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index e8c77d330479..93a8c34d6c7f 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -85,6 +85,20 @@ struct cpufreq_policy { struct list_head policy_list; struct kobject kobj; struct completion kobj_unregister; + + /* + * The rules for this semaphore: + * - Any routine that wants to read from the policy structure will + * do a down_read on this semaphore. + * - Any routine that will write to the policy structure and/or may take away + * the policy altogether (eg. CPU hotplug), will hold this lock in write + * mode before doing so. + * + * Additional rules: + * - Lock should not be held across + * __cpufreq_governor(data, CPUFREQ_GOV_POLICY_EXIT); + */ + struct rw_semaphore rwsem; }; /* Only for ACPI */ |