cpufreq: governor: Keep single copy of information common to policy->cpus
Some information is common to all CPUs belonging to a policy, but are
kept on per-cpu basis. Lets keep that in another structure common to all
policy->cpus. That will make updates/reads to that less complex and less
error prone.
The memory for cpu_common_dbs_info is allocated/freed at INIT/EXIT, so
that it we don't reallocate it for STOP/START sequence. It will be also
be used (in next patch) while the governor is stopped and so must not be
freed that early.
Reviewed-and-tested-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/cpufreq/cpufreq_governor.c b/drivers/cpufreq/cpufreq_governor.c
index c0566f8..b01cb72 100644
--- a/drivers/cpufreq/cpufreq_governor.c
+++ b/drivers/cpufreq/cpufreq_governor.c
@@ -35,7 +35,7 @@
struct cpu_dbs_info *cdbs = dbs_data->cdata->get_cpu_cdbs(cpu);
struct od_dbs_tuners *od_tuners = dbs_data->tuners;
struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
- struct cpufreq_policy *policy;
+ struct cpufreq_policy *policy = cdbs->shared->policy;
unsigned int sampling_rate;
unsigned int max_load = 0;
unsigned int ignore_nice;
@@ -60,8 +60,6 @@
ignore_nice = cs_tuners->ignore_nice_load;
}
- policy = cdbs->policy;
-
/* Get Absolute Load */
for_each_cpu(j, policy->cpus) {
struct cpu_dbs_info *j_cdbs;
@@ -209,17 +207,18 @@
}
/* Will return if we need to evaluate cpu load again or not */
-bool need_load_eval(struct cpu_dbs_info *cdbs, unsigned int sampling_rate)
+bool need_load_eval(struct cpu_common_dbs_info *shared,
+ unsigned int sampling_rate)
{
- if (policy_is_shared(cdbs->policy)) {
+ if (policy_is_shared(shared->policy)) {
ktime_t time_now = ktime_get();
- s64 delta_us = ktime_us_delta(time_now, cdbs->time_stamp);
+ s64 delta_us = ktime_us_delta(time_now, shared->time_stamp);
/* Do nothing if we recently have sampled */
if (delta_us < (s64)(sampling_rate / 2))
return false;
else
- cdbs->time_stamp = time_now;
+ shared->time_stamp = time_now;
}
return true;
@@ -238,6 +237,37 @@
}
}
+static int alloc_common_dbs_info(struct cpufreq_policy *policy,
+ struct common_dbs_data *cdata)
+{
+ struct cpu_common_dbs_info *shared;
+ int j;
+
+ /* Allocate memory for the common information for policy->cpus */
+ shared = kzalloc(sizeof(*shared), GFP_KERNEL);
+ if (!shared)
+ return -ENOMEM;
+
+ /* Set shared for all CPUs, online+offline */
+ for_each_cpu(j, policy->related_cpus)
+ cdata->get_cpu_cdbs(j)->shared = shared;
+
+ return 0;
+}
+
+static void free_common_dbs_info(struct cpufreq_policy *policy,
+ struct common_dbs_data *cdata)
+{
+ struct cpu_dbs_info *cdbs = cdata->get_cpu_cdbs(policy->cpu);
+ struct cpu_common_dbs_info *shared = cdbs->shared;
+ int j;
+
+ for_each_cpu(j, policy->cpus)
+ cdata->get_cpu_cdbs(j)->shared = NULL;
+
+ kfree(shared);
+}
+
static int cpufreq_governor_init(struct cpufreq_policy *policy,
struct dbs_data *dbs_data,
struct common_dbs_data *cdata)
@@ -248,6 +278,11 @@
if (dbs_data) {
if (WARN_ON(have_governor_per_policy()))
return -EINVAL;
+
+ ret = alloc_common_dbs_info(policy, cdata);
+ if (ret)
+ return ret;
+
dbs_data->usage_count++;
policy->governor_data = dbs_data;
return 0;
@@ -257,12 +292,16 @@
if (!dbs_data)
return -ENOMEM;
+ ret = alloc_common_dbs_info(policy, cdata);
+ if (ret)
+ goto free_dbs_data;
+
dbs_data->cdata = cdata;
dbs_data->usage_count = 1;
ret = cdata->init(dbs_data, !policy->governor->initialized);
if (ret)
- goto free_dbs_data;
+ goto free_common_dbs_info;
/* policy latency is in ns. Convert it to us first */
latency = policy->cpuinfo.transition_latency / 1000;
@@ -299,6 +338,8 @@
}
cdata_exit:
cdata->exit(dbs_data, !policy->governor->initialized);
+free_common_dbs_info:
+ free_common_dbs_info(policy, cdata);
free_dbs_data:
kfree(dbs_data);
return ret;
@@ -322,6 +363,8 @@
cdata->exit(dbs_data, policy->governor->initialized == 1);
kfree(dbs_data);
}
+
+ free_common_dbs_info(policy, cdata);
}
static int cpufreq_governor_start(struct cpufreq_policy *policy,
@@ -330,6 +373,7 @@
struct common_dbs_data *cdata = dbs_data->cdata;
unsigned int sampling_rate, ignore_nice, j, cpu = policy->cpu;
struct cpu_dbs_info *cdbs = cdata->get_cpu_cdbs(cpu);
+ struct cpu_common_dbs_info *shared = cdbs->shared;
int io_busy = 0;
if (!policy->cur)
@@ -348,11 +392,14 @@
io_busy = od_tuners->io_is_busy;
}
+ shared->policy = policy;
+ shared->time_stamp = ktime_get();
+ mutex_init(&shared->timer_mutex);
+
for_each_cpu(j, policy->cpus) {
struct cpu_dbs_info *j_cdbs = cdata->get_cpu_cdbs(j);
unsigned int prev_load;
- j_cdbs->policy = policy;
j_cdbs->prev_cpu_idle =
get_cpu_idle_time(j, &j_cdbs->prev_cpu_wall, io_busy);
@@ -364,7 +411,6 @@
if (ignore_nice)
j_cdbs->prev_cpu_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE];
- mutex_init(&j_cdbs->timer_mutex);
INIT_DEFERRABLE_WORK(&j_cdbs->dwork, cdata->gov_dbs_timer);
}
@@ -384,9 +430,6 @@
od_ops->powersave_bias_init_cpu(cpu);
}
- /* Initiate timer time stamp */
- cdbs->time_stamp = ktime_get();
-
gov_queue_work(dbs_data, policy, delay_for_sampling_rate(sampling_rate),
true);
return 0;
@@ -398,6 +441,9 @@
struct common_dbs_data *cdata = dbs_data->cdata;
unsigned int cpu = policy->cpu;
struct cpu_dbs_info *cdbs = cdata->get_cpu_cdbs(cpu);
+ struct cpu_common_dbs_info *shared = cdbs->shared;
+
+ gov_cancel_work(dbs_data, policy);
if (cdata->governor == GOV_CONSERVATIVE) {
struct cs_cpu_dbs_info_s *cs_dbs_info =
@@ -406,10 +452,8 @@
cs_dbs_info->enable = 0;
}
- gov_cancel_work(dbs_data, policy);
-
- mutex_destroy(&cdbs->timer_mutex);
- cdbs->policy = NULL;
+ shared->policy = NULL;
+ mutex_destroy(&shared->timer_mutex);
}
static void cpufreq_governor_limits(struct cpufreq_policy *policy,
@@ -419,18 +463,18 @@
unsigned int cpu = policy->cpu;
struct cpu_dbs_info *cdbs = cdata->get_cpu_cdbs(cpu);
- if (!cdbs->policy)
+ if (!cdbs->shared || !cdbs->shared->policy)
return;
- mutex_lock(&cdbs->timer_mutex);
- if (policy->max < cdbs->policy->cur)
- __cpufreq_driver_target(cdbs->policy, policy->max,
+ mutex_lock(&cdbs->shared->timer_mutex);
+ if (policy->max < cdbs->shared->policy->cur)
+ __cpufreq_driver_target(cdbs->shared->policy, policy->max,
CPUFREQ_RELATION_H);
- else if (policy->min > cdbs->policy->cur)
- __cpufreq_driver_target(cdbs->policy, policy->min,
+ else if (policy->min > cdbs->shared->policy->cur)
+ __cpufreq_driver_target(cdbs->shared->policy, policy->min,
CPUFREQ_RELATION_L);
dbs_check_cpu(dbs_data, cpu);
- mutex_unlock(&cdbs->timer_mutex);
+ mutex_unlock(&cdbs->shared->timer_mutex);
}
int cpufreq_governor_dbs(struct cpufreq_policy *policy,