@@ -50,15 +50,14 @@ struct cpufreq_cooling_device {
unsigned int cpufreq_state;
unsigned int cpufreq_val;
struct cpumask allowed_cpus;
+ struct list_head node;
};
static DEFINE_IDR(cpufreq_idr);
static DEFINE_MUTEX(cooling_cpufreq_lock);
static unsigned int cpufreq_dev_count;
-/* notify_table passes value to the CPUFREQ_ADJUST callback function. */
-#define NOTIFY_INVALID NULL
-static struct cpufreq_cooling_device *notify_device;
+static LIST_HEAD(cpufreq_dev_list);
/**
* get_idr - function to get a unique id.
@@ -287,15 +286,12 @@ static int cpufreq_apply_cooling(struct cpufreq_cooling_device *cpufreq_device,
cpufreq_device->cpufreq_state = cooling_state;
cpufreq_device->cpufreq_val = clip_freq;
- notify_device = cpufreq_device;
for_each_cpu(cpuid, mask) {
if (is_cpufreq_valid(cpuid))
cpufreq_update_policy(cpuid);
}
- notify_device = NOTIFY_INVALID;
-
return 0;
}
@@ -316,21 +312,28 @@ static int cpufreq_thermal_notifier(struct notifier_block *nb,
{
struct cpufreq_policy *policy = data;
unsigned long max_freq = 0;
+ struct cpufreq_cooling_device *cpufreq_dev;
- if (event != CPUFREQ_ADJUST || notify_device == NOTIFY_INVALID)
+ if (event != CPUFREQ_ADJUST)
return 0;
- if (cpumask_test_cpu(policy->cpu, ¬ify_device->allowed_cpus))
- max_freq = notify_device->cpufreq_val;
- else
- return 0;
+ mutex_lock(&cooling_cpufreq_lock);
+ list_for_each_entry(cpufreq_dev, &cpufreq_dev_list, node) {
+ if (!cpumask_test_cpu(policy->cpu,
+ &cpufreq_dev->allowed_cpus))
+ continue;
+
+ if (!cpufreq_dev->cpufreq_val)
+ cpufreq_dev->cpufreq_val = get_cpu_frequency(
+ cpumask_any(&cpufreq_dev->allowed_cpus),
+ cpufreq_dev->cpufreq_state);
- /* Never exceed user_policy.max */
- if (max_freq > policy->user_policy.max)
- max_freq = policy->user_policy.max;
+ max_freq = cpufreq_dev->cpufreq_val;
- if (policy->max != max_freq)
- cpufreq_verify_within_limits(policy, 0, max_freq);
+ if (policy->max != max_freq)
+ cpufreq_verify_within_limits(policy, 0, max_freq);
+ }
+ mutex_unlock(&cooling_cpufreq_lock);
return 0;
}
@@ -486,6 +489,7 @@ __cpufreq_cooling_register(struct device_node *np,
cpufreq_register_notifier(&thermal_cpufreq_notifier_block,
CPUFREQ_POLICY_NOTIFIER);
cpufreq_dev_count++;
+ list_add(&cpufreq_dev->node, &cpufreq_dev_list);
mutex_unlock(&cooling_cpufreq_lock);
@@ -549,6 +553,7 @@ void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev)
cpufreq_dev = cdev->devdata;
mutex_lock(&cooling_cpufreq_lock);
+ list_del(&cpufreq_dev->node);
cpufreq_dev_count--;
/* Unregister the notifier for the last cpufreq cooling device */
Existing code updates cupfreq policy only while executing cpufreq_apply_cooling() function (i.e. when notify_device != NOTIFY_INVALID). It doesn't apply constraints when cpufreq policy update happens from any other place but it should update the cpufreq policy with thermal constraints every time when there is a cpufreq policy update, to keep state of cpufreq_cooling_device and max_feq of cpufreq policy in sync. For instance while resuming cpufreq updates cpufreq_policy and it restores default policy->usr_policy values irrespective of cooling device's cpufreq_state since notification gets missed because (notify_device == NOTIFY_INVALID). Another problem, is that userspace is able to change max_freq irrespective of cooling device's state, as notification gets missed. This patch modifies code to maintain a global cpufreq_dev_list and applies constraints of all matching cooling devices for policy's cpu when there is any policy update(ends up applying the lowest max_freq among the matching cpu cooling devices). This patch also removes redundant check (max_freq > policy->user_policy.max), as cpufreq framework takes care of user_policy constraints already where ever required, otherwise its causing an issue while increasing max_freq in normal scenerio as it restores max_freq with policy->user_policy.max which is old (smaller) value. Signed-off-by: Yadwinder Singh Brar <yadi.brar@samsung.com> --- changes since v1: - Updated commit message as suggested by Eduardo Valentin - fixed an issue in incresing value of scaling_max_freq from sysfs after decreasing it once in normal thermal conditions also. --- drivers/thermal/cpu_cooling.c | 37 +++++++++++++++++++++---------------- 1 files changed, 21 insertions(+), 16 deletions(-)