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Message-Id: <3c2f4624ca6f5688036c2fd59fceb1798fd8c0ee.1376979090.git.viresh.kumar@linaro.org>
Date: Tue, 20 Aug 2013 12:08:25 +0530
From: Viresh Kumar <viresh.kumar@...aro.org>
To: rjw@...k.pl
Cc: linaro-kernel@...ts.linaro.org, patches@...aro.org,
cpufreq@...r.kernel.org, linux-pm@...r.kernel.org,
linux-kernel@...r.kernel.org,
Viresh Kumar <viresh.kumar@...aro.org>
Subject: [PATCH 4/5] cpufreq: remove cpufreq_policy_cpu per-cpu variable
cpufreq_policy_cpu per-cpu variables are used for storing cpu that manages a cpu
or its policy->cpu. We are also storing policy for each cpu in cpufreq_cpu_data
and so this information is just redundant.
Better use cpufreq_cpu_data to retrieve policy and get policy->cpu from there.
And so this patch removes cpufreq_policy_cpu per-cpu variable.
Signed-off-by: Viresh Kumar <viresh.kumar@...aro.org>
---
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 b03a851..0586bd2 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);
--
1.7.12.rc2.18.g61b472e
--
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