diff options
| -rw-r--r-- | drivers/cpufreq/cpufreq_ondemand.c | 62 |
1 files changed, 27 insertions, 35 deletions
diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c index 246ae147df7..d6ba14276bb 100644 --- a/drivers/cpufreq/cpufreq_ondemand.c +++ b/drivers/cpufreq/cpufreq_ondemand.c @@ -70,8 +70,13 @@ struct cpu_dbs_info_s { unsigned int freq_lo_jiffies; unsigned int freq_hi_jiffies; int cpu; - unsigned int enable:1, - sample_type:1; + unsigned int sample_type:1; + /* + * percpu mutex that serializes governor limit change with + * do_dbs_timer invocation. We do not want do_dbs_timer to run + * when user is changing the governor or limits. + */ + struct mutex timer_mutex; }; static DEFINE_PER_CPU(struct cpu_dbs_info_s, cpu_dbs_info); @@ -79,9 +84,7 @@ static unsigned int dbs_enable; /* number of CPUs using this policy */ /* * dbs_mutex protects data in dbs_tuners_ins from concurrent changes on - * different CPUs. It protects dbs_enable in governor start/stop. It also - * serializes governor limit_change with do_dbs_timer. We do not want - * do_dbs_timer to run when user is changing the governor or limits. + * different CPUs. It protects dbs_enable in governor start/stop. */ static DEFINE_MUTEX(dbs_mutex); @@ -187,13 +190,18 @@ static unsigned int powersave_bias_target(struct cpufreq_policy *policy, return freq_hi; } +static void ondemand_powersave_bias_init_cpu(int cpu) +{ + struct cpu_dbs_info_s *dbs_info = &per_cpu(cpu_dbs_info, cpu); + dbs_info->freq_table = cpufreq_frequency_get_table(cpu); + dbs_info->freq_lo = 0; +} + static void ondemand_powersave_bias_init(void) { int i; for_each_online_cpu(i) { - struct cpu_dbs_info_s *dbs_info = &per_cpu(cpu_dbs_info, i); - dbs_info->freq_table = cpufreq_frequency_get_table(i); - dbs_info->freq_lo = 0; + ondemand_powersave_bias_init_cpu(i); } } @@ -235,12 +243,10 @@ static ssize_t store_sampling_rate(struct cpufreq_policy *unused, unsigned int input; int ret; ret = sscanf(buf, "%u", &input); + if (ret != 1) + return -EINVAL; mutex_lock(&dbs_mutex); - if (ret != 1) { - mutex_unlock(&dbs_mutex); - return -EINVAL; - } dbs_tuners_ins.sampling_rate = max(input, min_sampling_rate); mutex_unlock(&dbs_mutex); @@ -254,13 +260,12 @@ static ssize_t store_up_threshold(struct cpufreq_policy *unused, int ret; ret = sscanf(buf, "%u", &input); - mutex_lock(&dbs_mutex); if (ret != 1 || input > MAX_FREQUENCY_UP_THRESHOLD || input < MIN_FREQUENCY_UP_THRESHOLD) { - mutex_unlock(&dbs_mutex); return -EINVAL; } + mutex_lock(&dbs_mutex); dbs_tuners_ins.up_threshold = input; mutex_unlock(&dbs_mutex); @@ -358,9 +363,6 @@ static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info) struct cpufreq_policy *policy; unsigned int j; - if (!this_dbs_info->enable) - return; - this_dbs_info->freq_lo = 0; policy = this_dbs_info->cur_policy; @@ -488,13 +490,7 @@ static void do_dbs_timer(struct work_struct *work) int delay = usecs_to_jiffies(dbs_tuners_ins.sampling_rate); delay -= jiffies % delay; - - mutex_lock(&dbs_mutex); - - if (!dbs_info->enable) { - mutex_unlock(&dbs_mutex); - return; - } + mutex_lock(&dbs_info->timer_mutex); /* Common NORMAL_SAMPLE setup */ dbs_info->sample_type = DBS_NORMAL_SAMPLE; @@ -511,7 +507,7 @@ static void do_dbs_timer(struct work_struct *work) dbs_info->freq_lo, CPUFREQ_RELATION_H); } queue_delayed_work_on(cpu, kondemand_wq, &dbs_info->work, delay); - mutex_unlock(&dbs_mutex); + mutex_unlock(&dbs_info->timer_mutex); } static inline void dbs_timer_init(struct cpu_dbs_info_s *dbs_info) @@ -520,8 +516,6 @@ static inline void dbs_timer_init(struct cpu_dbs_info_s *dbs_info) int delay = usecs_to_jiffies(dbs_tuners_ins.sampling_rate); delay -= jiffies % delay; - dbs_info->enable = 1; - ondemand_powersave_bias_init(); dbs_info->sample_type = DBS_NORMAL_SAMPLE; INIT_DELAYED_WORK_DEFERRABLE(&dbs_info->work, do_dbs_timer); queue_delayed_work_on(dbs_info->cpu, kondemand_wq, &dbs_info->work, @@ -530,7 +524,6 @@ static inline void dbs_timer_init(struct cpu_dbs_info_s *dbs_info) static inline void dbs_timer_exit(struct cpu_dbs_info_s *dbs_info) { - dbs_info->enable = 0; cancel_delayed_work_sync(&dbs_info->work); } @@ -549,19 +542,15 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy, if ((!cpu_online(cpu)) || (!policy->cur)) return -EINVAL; - if (this_dbs_info->enable) /* Already enabled */ - break; - mutex_lock(&dbs_mutex); - dbs_enable++; rc = sysfs_create_group(&policy->kobj, &dbs_attr_group); if (rc) { - dbs_enable--; mutex_unlock(&dbs_mutex); return rc; } + dbs_enable++; for_each_cpu(j, policy->cpus) { struct cpu_dbs_info_s *j_dbs_info; j_dbs_info = &per_cpu(cpu_dbs_info, j); @@ -575,6 +564,8 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy, } } this_dbs_info->cpu = cpu; + ondemand_powersave_bias_init_cpu(cpu); + mutex_init(&this_dbs_info->timer_mutex); /* * Start the timerschedule work, when this governor * is used for first time @@ -602,20 +593,21 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy, mutex_lock(&dbs_mutex); sysfs_remove_group(&policy->kobj, &dbs_attr_group); + mutex_destroy(&this_dbs_info->timer_mutex); dbs_enable--; mutex_unlock(&dbs_mutex); break; case CPUFREQ_GOV_LIMITS: - mutex_lock(&dbs_mutex); + mutex_lock(&this_dbs_info->timer_mutex); if (policy->max < this_dbs_info->cur_policy->cur) __cpufreq_driver_target(this_dbs_info->cur_policy, policy->max, CPUFREQ_RELATION_H); else if (policy->min > this_dbs_info->cur_policy->cur) __cpufreq_driver_target(this_dbs_info->cur_policy, policy->min, CPUFREQ_RELATION_L); - mutex_unlock(&dbs_mutex); + mutex_unlock(&this_dbs_info->timer_mutex); break; } return 0; |