From 474deff744c4012f07cfa994947d7c6260c9ab89 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Tue, 20 Aug 2013 12:08:25 +0530 Subject: [PATCH] cpufreq: remove cpufreq_policy_cpu per-cpu variable cpufreq_policy_cpu per-cpu variables are used for storing the ID of the CPU that manages the given CPU's policy. However, we also store a policy pointer for each cpu in cpufreq_cpu_data, so the cpufreq_policy_cpu information is simply redundant. It is better to use cpufreq_cpu_data to retrieve a policy and get policy->cpu from there, so make that happen everywhere and drop the cpufreq_policy_cpu per-cpu variables which aren't necessary any more. [rjw: Changelog] Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/cpufreq.c | 45 +++++++++------------------------------ 1 file changed, 10 insertions(+), 35 deletions(-) diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index b03a8514b574..0586bd20a474 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -64,15 +64,14 @@ static DEFINE_PER_CPU(char[CPUFREQ_NAME_LEN], cpufreq_cpu_governor); * - Lock should not be held across * __cpufreq_governor(data, CPUFREQ_GOV_STOP); */ -static DEFINE_PER_CPU(int, cpufreq_policy_cpu); static DEFINE_PER_CPU(struct rw_semaphore, cpu_policy_rwsem); #define lock_policy_rwsem(mode, cpu) \ static int lock_policy_rwsem_##mode(int cpu) \ { \ - int policy_cpu = per_cpu(cpufreq_policy_cpu, cpu); \ - BUG_ON(policy_cpu == -1); \ - down_##mode(&per_cpu(cpu_policy_rwsem, policy_cpu)); \ + struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); \ + BUG_ON(!policy); \ + down_##mode(&per_cpu(cpu_policy_rwsem, policy->cpu)); \ \ return 0; \ } @@ -83,9 +82,9 @@ lock_policy_rwsem(write, cpu); #define unlock_policy_rwsem(mode, cpu) \ static void unlock_policy_rwsem_##mode(int cpu) \ { \ - int policy_cpu = per_cpu(cpufreq_policy_cpu, cpu); \ - BUG_ON(policy_cpu == -1); \ - up_##mode(&per_cpu(cpu_policy_rwsem, policy_cpu)); \ + struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); \ + BUG_ON(!policy); \ + up_##mode(&per_cpu(cpu_policy_rwsem, policy->cpu)); \ } unlock_policy_rwsem(read, cpu); @@ -887,7 +886,6 @@ static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, write_lock_irqsave(&cpufreq_driver_lock, flags); cpumask_set_cpu(cpu, policy->cpus); - per_cpu(cpufreq_policy_cpu, cpu) = policy->cpu; per_cpu(cpufreq_cpu_data, cpu) = policy; write_unlock_irqrestore(&cpufreq_driver_lock, flags); @@ -1013,9 +1011,6 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif, policy->governor = CPUFREQ_DEFAULT_GOVERNOR; cpumask_copy(policy->cpus, cpumask_of(cpu)); - /* Initially set CPU itself as the policy_cpu */ - per_cpu(cpufreq_policy_cpu, cpu) = cpu; - init_completion(&policy->kobj_unregister); INIT_WORK(&policy->update, handle_update); @@ -1053,10 +1048,8 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif, #endif write_lock_irqsave(&cpufreq_driver_lock, flags); - for_each_cpu(j, policy->cpus) { + for_each_cpu(j, policy->cpus) per_cpu(cpufreq_cpu_data, j) = policy; - per_cpu(cpufreq_policy_cpu, j) = policy->cpu; - } write_unlock_irqrestore(&cpufreq_driver_lock, flags); if (!frozen) { @@ -1080,15 +1073,11 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif, err_out_unregister: write_lock_irqsave(&cpufreq_driver_lock, flags); - for_each_cpu(j, policy->cpus) { + for_each_cpu(j, policy->cpus) per_cpu(cpufreq_cpu_data, j) = NULL; - if (j != cpu) - per_cpu(cpufreq_policy_cpu, j) = -1; - } write_unlock_irqrestore(&cpufreq_driver_lock, flags); err_set_policy_cpu: - per_cpu(cpufreq_policy_cpu, cpu) = -1; cpufreq_policy_free(policy); nomem_out: up_read(&cpufreq_rwsem); @@ -1112,14 +1101,9 @@ static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) static void update_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) { - int j; - policy->last_cpu = policy->cpu; policy->cpu = cpu; - for_each_cpu(j, policy->cpus) - per_cpu(cpufreq_policy_cpu, j) = cpu; - #ifdef CONFIG_CPU_FREQ_TABLE cpufreq_frequency_table_update_policy_cpu(policy); #endif @@ -1131,7 +1115,6 @@ static int cpufreq_nominate_new_policy_cpu(struct cpufreq_policy *policy, unsigned int old_cpu, bool frozen) { struct device *cpu_dev; - unsigned long flags; int ret; /* first sibling now owns the new sysfs dir */ @@ -1148,11 +1131,6 @@ static int cpufreq_nominate_new_policy_cpu(struct cpufreq_policy *policy, WARN_ON(lock_policy_rwsem_write(old_cpu)); cpumask_set_cpu(old_cpu, policy->cpus); - - write_lock_irqsave(&cpufreq_driver_lock, flags); - per_cpu(cpufreq_cpu_data, old_cpu) = policy; - write_unlock_irqrestore(&cpufreq_driver_lock, flags); - unlock_policy_rwsem_write(old_cpu); ret = sysfs_create_link(&cpu_dev->kobj, &policy->kobj, @@ -1186,7 +1164,6 @@ static int __cpufreq_remove_dev(struct device *dev, write_lock_irqsave(&cpufreq_driver_lock, flags); policy = per_cpu(cpufreq_cpu_data, cpu); - per_cpu(cpufreq_cpu_data, cpu) = NULL; /* Save the policy somewhere when doing a light-weight tear-down */ if (frozen) @@ -1292,7 +1269,7 @@ static int __cpufreq_remove_dev(struct device *dev, } } - per_cpu(cpufreq_policy_cpu, cpu) = -1; + per_cpu(cpufreq_cpu_data, cpu) = NULL; return 0; } @@ -2148,10 +2125,8 @@ static int __init cpufreq_core_init(void) if (cpufreq_disabled()) return -ENODEV; - for_each_possible_cpu(cpu) { - per_cpu(cpufreq_policy_cpu, cpu) = -1; + for_each_possible_cpu(cpu) init_rwsem(&per_cpu(cpu_policy_rwsem, cpu)); - } cpufreq_global_kobject = kobject_create(); BUG_ON(!cpufreq_global_kobject);