cpufreq: governor: Use common mutex for dbs_data protection
Every governor relying on the common code in cpufreq_governor.c
has to provide its own mutex in struct common_dbs_data. However,
there actually is no need to have a separate mutex per governor
for this purpose, they may be using the same global mutex just
fine. Accordingly, introduce a single common mutex for that and
drop the mutex field from struct common_dbs_data.
That at least will ensure that the mutex is always present and
initialized regardless of what the particular governors do.
Another benefit is that the common code does not need a pointer to
a governor-related structure to get to the mutex which sometimes
helps.
Finally, it makes the code generally easier to follow.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Saravana Kannan <skannan@codeaurora.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c
index bc002c8..8f0c3db 100644
--- a/drivers/cpufreq/cpufreq_conservative.c
+++ b/drivers/cpufreq/cpufreq_conservative.c
@@ -368,7 +368,6 @@
.gov_check_cpu = cs_check_cpu,
.init = cs_init,
.exit = cs_exit,
- .mutex = __MUTEX_INITIALIZER(cs_dbs_cdata.mutex),
};
static int cs_cpufreq_governor_dbs(struct cpufreq_policy *policy,
diff --git a/drivers/cpufreq/cpufreq_governor.c b/drivers/cpufreq/cpufreq_governor.c
index 6bc2f50..f291fdd 100644
--- a/drivers/cpufreq/cpufreq_governor.c
+++ b/drivers/cpufreq/cpufreq_governor.c
@@ -22,6 +22,9 @@
#include "cpufreq_governor.h"
+DEFINE_MUTEX(dbs_data_mutex);
+EXPORT_SYMBOL_GPL(dbs_data_mutex);
+
static struct attribute_group *get_sysfs_attr(struct dbs_data *dbs_data)
{
if (have_governor_per_policy())
@@ -543,7 +546,7 @@
int ret;
/* Lock governor to block concurrent initialization of governor */
- mutex_lock(&cdata->mutex);
+ mutex_lock(&dbs_data_mutex);
if (have_governor_per_policy())
dbs_data = policy->governor_data;
@@ -576,7 +579,7 @@
}
unlock:
- mutex_unlock(&cdata->mutex);
+ mutex_unlock(&dbs_data_mutex);
return ret;
}
diff --git a/drivers/cpufreq/cpufreq_governor.h b/drivers/cpufreq/cpufreq_governor.h
index 5417771..a9df62e 100644
--- a/drivers/cpufreq/cpufreq_governor.h
+++ b/drivers/cpufreq/cpufreq_governor.h
@@ -228,11 +228,6 @@
/* Governor specific ops, see below */
void *gov_ops;
-
- /*
- * Protects governor's data (struct dbs_data and struct common_dbs_data)
- */
- struct mutex mutex;
};
/* Governor Per policy data */
@@ -277,6 +272,7 @@
return sprintf(buf, "%u\n", dbs_data->min_sampling_rate); \
}
+extern struct mutex dbs_data_mutex;
extern struct mutex cpufreq_governor_lock;
void dbs_check_cpu(struct dbs_data *dbs_data, int cpu);
int cpufreq_governor_dbs(struct cpufreq_policy *policy,
diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c
index da7f351..fac2f8f 100644
--- a/drivers/cpufreq/cpufreq_ondemand.c
+++ b/drivers/cpufreq/cpufreq_ondemand.c
@@ -249,7 +249,7 @@
/*
* Lock governor so that governor start/stop can't execute in parallel.
*/
- mutex_lock(&od_dbs_cdata.mutex);
+ mutex_lock(&dbs_data_mutex);
cpumask_copy(&cpumask, cpu_online_mask);
@@ -306,7 +306,7 @@
}
}
- mutex_unlock(&od_dbs_cdata.mutex);
+ mutex_unlock(&dbs_data_mutex);
}
static ssize_t store_sampling_rate(struct dbs_data *dbs_data, const char *buf,
@@ -552,7 +552,6 @@
.gov_ops = &od_ops,
.init = od_init,
.exit = od_exit,
- .mutex = __MUTEX_INITIALIZER(od_dbs_cdata.mutex),
};
static int od_cpufreq_governor_dbs(struct cpufreq_policy *policy,