From ca40c7542f0cd0e0dfa074bd4ccefc04b8561427 Mon Sep 17 00:00:00 2001 From: Maarten ter Huurne Date: Tue, 2 Aug 2011 10:26:09 +0200 Subject: [PATCH 10/21] cpufreq_stats: Support runtime changes to frequency table. --- drivers/cpufreq/cpufreq_stats.c | 161 ++++++++++++++++++++------------------- 1 files changed, 83 insertions(+), 78 deletions(-) --- a/drivers/cpufreq/cpufreq_stats.c +++ b/drivers/cpufreq/cpufreq_stats.c @@ -20,6 +20,7 @@ #include #include #include +#include #include static spinlock_t cpufreq_stats_lock; @@ -36,7 +37,7 @@ struct cpufreq_stats { unsigned long long last_time; unsigned int max_state; unsigned int state_num; - unsigned int last_index; + int last_index; cputime64_t *time_in_state; unsigned int *freq_table; #ifdef CONFIG_CPU_FREQ_STAT_DETAILS @@ -59,7 +60,7 @@ static int cpufreq_stats_update(unsigned cur_time = get_jiffies_64(); spin_lock(&cpufreq_stats_lock); stat = per_cpu(cpufreq_stats_table, cpu); - if (stat->time_in_state) + if (stat->time_in_state && stat->last_index != -1) stat->time_in_state[stat->last_index] += cur_time - stat->last_time; stat->last_time = cur_time; @@ -81,7 +82,7 @@ static ssize_t show_time_in_state(struct ssize_t len = 0; int i; struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu); - if (!stat) + if (!stat || !stat->time_in_state) return 0; cpufreq_stats_update(stat->cpu); for (i = 0; i < stat->state_num; i++) { @@ -99,7 +100,7 @@ static ssize_t show_trans_table(struct c int i, j; struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu); - if (!stat) + if (!stat || !stat->trans_table) return 0; cpufreq_stats_update(stat->cpu); len += snprintf(buf + len, PAGE_SIZE - len, " From : To\n"); @@ -158,63 +159,35 @@ static struct attribute_group stats_attr static int freq_table_get_index(struct cpufreq_stats *stat, unsigned int freq) { int index; - for (index = 0; index < stat->max_state; index++) - if (stat->freq_table[index] == freq) - return index; + if (stat->freq_table) + for (index = 0; index < stat->max_state; index++) + if (stat->freq_table[index] == freq) + return index; return -1; } -/* should be called late in the CPU removal sequence so that the stats - * memory is still available in case someone tries to use it. - */ static void cpufreq_stats_free_table(unsigned int cpu) { struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, cpu); + struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); + if (policy && policy->cpu == cpu) + sysfs_remove_group(&policy->kobj, &stats_attr_group); if (stat) { kfree(stat->time_in_state); kfree(stat); } per_cpu(cpufreq_stats_table, cpu) = NULL; -} - -/* must be called early in the CPU removal sequence (before - * cpufreq_remove_dev) so that policy is still valid. - */ -static void cpufreq_stats_free_sysfs(unsigned int cpu) -{ - struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); - if (policy && policy->cpu == cpu) - sysfs_remove_group(&policy->kobj, &stats_attr_group); if (policy) cpufreq_cpu_put(policy); } -static int cpufreq_stats_create_table(struct cpufreq_policy *policy, +static int cpufreq_stats_update_table(struct cpufreq_policy *policy, struct cpufreq_frequency_table *table) { - unsigned int i, j, count = 0, ret = 0; - struct cpufreq_stats *stat; - struct cpufreq_policy *data; + unsigned int i, j, count = 0; unsigned int alloc_size; unsigned int cpu = policy->cpu; - if (per_cpu(cpufreq_stats_table, cpu)) - return -EBUSY; - stat = kzalloc(sizeof(struct cpufreq_stats), GFP_KERNEL); - if ((stat) == NULL) - return -ENOMEM; - - data = cpufreq_cpu_get(cpu); - if (data == NULL) { - ret = -EINVAL; - goto error_get_fail; - } - - ret = sysfs_create_group(&data->kobj, &stats_attr_group); - if (ret) - goto error_out; - - stat->cpu = cpu; - per_cpu(cpufreq_stats_table, cpu) = stat; + struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, cpu); for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) { unsigned int freq = table[i].frequency; @@ -223,40 +196,73 @@ static int cpufreq_stats_create_table(st count++; } + if (stat->max_state != count) { + stat->max_state = count; + kfree(stat->time_in_state); + stat->time_in_state = NULL; + } alloc_size = count * sizeof(int) + count * sizeof(cputime64_t); - #ifdef CONFIG_CPU_FREQ_STAT_DETAILS alloc_size += count * count * sizeof(int); #endif - stat->max_state = count; - stat->time_in_state = kzalloc(alloc_size, GFP_KERNEL); - if (!stat->time_in_state) { - ret = -ENOMEM; - goto error_out; - } - stat->freq_table = (unsigned int *)(stat->time_in_state + count); - + if (stat->time_in_state) { + memset(stat->time_in_state, 0, alloc_size); + } else { + stat->time_in_state = kzalloc(alloc_size, GFP_KERNEL); + if (!stat->time_in_state) + return -ENOMEM; + stat->freq_table = (unsigned int *)( + stat->time_in_state + count); #ifdef CONFIG_CPU_FREQ_STAT_DETAILS - stat->trans_table = stat->freq_table + count; + stat->trans_table = stat->freq_table + count; #endif + } + j = 0; - for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) { - unsigned int freq = table[i].frequency; - if (freq == CPUFREQ_ENTRY_INVALID) - continue; - if (freq_table_get_index(stat, freq) == -1) - stat->freq_table[j++] = freq; + if (stat->freq_table) { + for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) { + unsigned int freq = table[i].frequency; + if (freq == CPUFREQ_ENTRY_INVALID) + continue; + if (freq_table_get_index(stat, freq) == -1) + stat->freq_table[j++] = freq; + } } stat->state_num = j; spin_lock(&cpufreq_stats_lock); stat->last_time = get_jiffies_64(); stat->last_index = freq_table_get_index(stat, policy->cur); spin_unlock(&cpufreq_stats_lock); + return 0; +} + +static int cpufreq_stats_create_table(struct cpufreq_policy *policy, + struct cpufreq_frequency_table *table) +{ + unsigned int ret = 0; + struct cpufreq_stats *stat; + struct cpufreq_policy *data; + unsigned int cpu = policy->cpu; + + stat = kzalloc(sizeof(struct cpufreq_stats), GFP_KERNEL); + if ((stat) == NULL) + return -ENOMEM; + + data = cpufreq_cpu_get(cpu); + if (data == NULL) { + ret = -EINVAL; + goto error_out; + } + ret = sysfs_create_group(&data->kobj, &stats_attr_group); cpufreq_cpu_put(data); + if (ret) + goto error_out; + + stat->cpu = cpu; + per_cpu(cpufreq_stats_table, cpu) = stat; + return 0; error_out: - cpufreq_cpu_put(data); -error_get_fail: kfree(stat); per_cpu(cpufreq_stats_table, cpu) = NULL; return ret; @@ -274,10 +280,12 @@ static int cpufreq_stat_notifier_policy( table = cpufreq_frequency_get_table(cpu); if (!table) return 0; - ret = cpufreq_stats_create_table(policy, table); - if (ret) - return ret; - return 0; + if (!per_cpu(cpufreq_stats_table, cpu)) { + ret = cpufreq_stats_create_table(policy, table); + if (ret) + return ret; + } + return cpufreq_stats_update_table(policy, table); } static int cpufreq_stat_notifier_trans(struct notifier_block *nb, @@ -297,21 +305,23 @@ static int cpufreq_stat_notifier_trans(s old_index = stat->last_index; new_index = freq_table_get_index(stat, freq->new); - /* We can't do stat->time_in_state[-1]= .. */ - if (old_index == -1 || new_index == -1) - return 0; - cpufreq_stats_update(freq->cpu); - if (old_index == new_index) return 0; + if (new_index == -1) + return 0; + spin_lock(&cpufreq_stats_lock); stat->last_index = new_index; + if (old_index != -1) { #ifdef CONFIG_CPU_FREQ_STAT_DETAILS - stat->trans_table[old_index * stat->max_state + new_index]++; + if (stat->trans_table) + stat->trans_table[old_index * stat->max_state + + new_index]++; #endif - stat->total_trans++; + stat->total_trans++; + } spin_unlock(&cpufreq_stats_lock); return 0; } @@ -327,9 +337,6 @@ static int __cpuinit cpufreq_stat_cpu_ca case CPU_ONLINE_FROZEN: cpufreq_update_policy(cpu); break; - case CPU_DOWN_PREPARE: - cpufreq_stats_free_sysfs(cpu); - break; case CPU_DEAD: case CPU_DEAD_FROZEN: cpufreq_stats_free_table(cpu); @@ -338,10 +345,9 @@ static int __cpuinit cpufreq_stat_cpu_ca return NOTIFY_OK; } -/* priority=1 so this will get called before cpufreq_remove_dev */ -static struct notifier_block cpufreq_stat_cpu_notifier __refdata = { +static struct notifier_block cpufreq_stat_cpu_notifier __refdata = +{ .notifier_call = cpufreq_stat_cpu_callback, - .priority = 1, }; static struct notifier_block notifier_policy_block = { @@ -388,7 +394,6 @@ static void __exit cpufreq_stats_exit(vo unregister_hotcpu_notifier(&cpufreq_stat_cpu_notifier); for_each_online_cpu(cpu) { cpufreq_stats_free_table(cpu); - cpufreq_stats_free_sysfs(cpu); } }