Most of the callers of cpufreq_frequency_get_table() already have the pointer to a valid 'policy' structure and they don't really need to go through the per-cpu variable first and then a check to validate the frequency, in order to find the freq-table for the policy.
Directly use the policy->freq_table field instead for them. Only one user of that API is left after above changes, cpu_cooling.c and it accesses the freq_table in a racy way as the policy can get freed in between. Fix it by using cpufreq_cpu_get() properly. Since there are no more users of cpufreq_frequency_get_table() left, get rid of it. Signed-off-by: Viresh Kumar <viresh.ku...@linaro.org> Acked-by: Javi Merino <javi.mer...@arm.com> (cpu_cooling.c) --- drivers/cpufreq/cpufreq.c | 38 +++++++++++++---------------------- drivers/cpufreq/cpufreq_ondemand.c | 2 +- drivers/cpufreq/cpufreq_stats.c | 3 +-- drivers/cpufreq/freq_table.c | 9 +++------ drivers/cpufreq/ppc_cbe_cpufreq_pmi.c | 3 +-- drivers/thermal/cpu_cooling.c | 24 +++++++++++++++++----- include/linux/cpufreq.h | 2 -- 7 files changed, 39 insertions(+), 42 deletions(-) diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index fbc97b1fa371..1833eda1f9d4 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -126,15 +126,6 @@ struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) } EXPORT_SYMBOL_GPL(get_governor_parent_kobj); -struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu) -{ - struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); - - return policy && !policy_is_inactive(policy) ? - policy->freq_table : NULL; -} -EXPORT_SYMBOL_GPL(cpufreq_frequency_get_table); - static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) { u64 idle_time; @@ -1950,7 +1941,7 @@ int __cpufreq_driver_target(struct cpufreq_policy *policy, if (!cpufreq_driver->target_index) return -EINVAL; - freq_table = cpufreq_frequency_get_table(policy->cpu); + freq_table = policy->freq_table; if (unlikely(!freq_table)) { pr_err("%s: Unable to find freq_table\n", __func__); return -EINVAL; @@ -2345,26 +2336,25 @@ static struct notifier_block __refdata cpufreq_cpu_notifier = { *********************************************************************/ static int cpufreq_boost_set_sw(int state) { - struct cpufreq_frequency_table *freq_table; struct cpufreq_policy *policy; int ret = -EINVAL; for_each_active_policy(policy) { - freq_table = cpufreq_frequency_get_table(policy->cpu); - if (freq_table) { - ret = cpufreq_frequency_table_cpuinfo(policy, - freq_table); - if (ret) { - pr_err("%s: Policy frequency update failed\n", - __func__); - break; - } + if (!policy->freq_table) + continue; - down_write(&policy->rwsem); - policy->user_policy.max = policy->max; - cpufreq_governor_limits(policy); - up_write(&policy->rwsem); + ret = cpufreq_frequency_table_cpuinfo(policy, + policy->freq_table); + if (ret) { + pr_err("%s: Policy frequency update failed\n", + __func__); + break; } + + down_write(&policy->rwsem); + policy->user_policy.max = policy->max; + cpufreq_governor_limits(policy); + up_write(&policy->rwsem); } return ret; diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c index c84fc2240d49..4d2fe2710c5d 100644 --- a/drivers/cpufreq/cpufreq_ondemand.c +++ b/drivers/cpufreq/cpufreq_ondemand.c @@ -113,7 +113,7 @@ static void ondemand_powersave_bias_init(struct cpufreq_policy *policy) { struct od_policy_dbs_info *dbs_info = to_dbs_info(policy->governor_data); - dbs_info->freq_table = cpufreq_frequency_get_table(policy->cpu); + dbs_info->freq_table = policy->freq_table; dbs_info->freq_lo = 0; } diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c index c6e7f81a0397..06d3abdffd3a 100644 --- a/drivers/cpufreq/cpufreq_stats.c +++ b/drivers/cpufreq/cpufreq_stats.c @@ -157,11 +157,10 @@ void cpufreq_stats_create_table(struct cpufreq_policy *policy) unsigned int i = 0, count = 0, ret = -ENOMEM; struct cpufreq_stats *stats; unsigned int alloc_size; - unsigned int cpu = policy->cpu; struct cpufreq_frequency_table *pos, *table; /* We need cpufreq table for creating stats table */ - table = cpufreq_frequency_get_table(cpu); + table = policy->freq_table; if (unlikely(!table)) return; diff --git a/drivers/cpufreq/freq_table.c b/drivers/cpufreq/freq_table.c index 4e5c5dbfed7a..f52b5473b1f4 100644 --- a/drivers/cpufreq/freq_table.c +++ b/drivers/cpufreq/freq_table.c @@ -106,12 +106,10 @@ EXPORT_SYMBOL_GPL(cpufreq_frequency_table_verify); */ int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy) { - struct cpufreq_frequency_table *table = - cpufreq_frequency_get_table(policy->cpu); - if (!table) + if (!policy->freq_table) return -ENODEV; - return cpufreq_frequency_table_verify(policy, table); + return cpufreq_frequency_table_verify(policy, policy->freq_table); } EXPORT_SYMBOL_GPL(cpufreq_generic_frequency_table_verify); @@ -210,9 +208,8 @@ EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target); int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy, unsigned int freq) { - struct cpufreq_frequency_table *pos, *table; + struct cpufreq_frequency_table *pos, *table = policy->freq_table; - table = cpufreq_frequency_get_table(policy->cpu); if (unlikely(!table)) { pr_debug("%s: Unable to find frequency table\n", __func__); return -ENOENT; diff --git a/drivers/cpufreq/ppc_cbe_cpufreq_pmi.c b/drivers/cpufreq/ppc_cbe_cpufreq_pmi.c index 7c4cd5c634f2..dc112481a408 100644 --- a/drivers/cpufreq/ppc_cbe_cpufreq_pmi.c +++ b/drivers/cpufreq/ppc_cbe_cpufreq_pmi.c @@ -94,7 +94,7 @@ static int pmi_notifier(struct notifier_block *nb, unsigned long event, void *data) { struct cpufreq_policy *policy = data; - struct cpufreq_frequency_table *cbe_freqs; + struct cpufreq_frequency_table *cbe_freqs = policy->freq_table; u8 node; /* Should this really be called for CPUFREQ_ADJUST and CPUFREQ_NOTIFY @@ -103,7 +103,6 @@ static int pmi_notifier(struct notifier_block *nb, if (event == CPUFREQ_START) return 0; - cbe_freqs = cpufreq_frequency_get_table(policy->cpu); node = cbe_cpu_to_node(policy->cpu); pr_debug("got notified, event=%lu, node=%u\n", event, node); diff --git a/drivers/thermal/cpu_cooling.c b/drivers/thermal/cpu_cooling.c index 6ceac4f2d4b2..4d678cfc81b1 100644 --- a/drivers/thermal/cpu_cooling.c +++ b/drivers/thermal/cpu_cooling.c @@ -787,22 +787,34 @@ __cpufreq_cooling_register(struct device_node *np, const struct cpumask *clip_cpus, u32 capacitance, get_static_t plat_static_func) { + struct cpufreq_policy *policy; struct thermal_cooling_device *cool_dev; struct cpufreq_cooling_device *cpufreq_dev; char dev_name[THERMAL_NAME_LENGTH]; struct cpufreq_frequency_table *pos, *table; + struct cpumask temp_mask; unsigned int freq, i, num_cpus; int ret; - table = cpufreq_frequency_get_table(cpumask_first(clip_cpus)); + cpumask_and(&temp_mask, clip_cpus, cpu_online_mask); + policy = cpufreq_cpu_get(cpumask_first(&temp_mask)); + if (!policy) { + pr_debug("%s: CPUFreq policy not found\n", __func__); + return ERR_PTR(-EPROBE_DEFER); + } + + table = policy->freq_table; if (!table) { pr_debug("%s: CPUFreq table not found\n", __func__); - return ERR_PTR(-EPROBE_DEFER); + cool_dev = ERR_PTR(-ENODEV); + goto put_policy; } cpufreq_dev = kzalloc(sizeof(*cpufreq_dev), GFP_KERNEL); - if (!cpufreq_dev) - return ERR_PTR(-ENOMEM); + if (!cpufreq_dev) { + cool_dev = ERR_PTR(-ENOMEM); + goto put_policy; + } num_cpus = cpumask_weight(clip_cpus); cpufreq_dev->time_in_idle = kcalloc(num_cpus, @@ -892,7 +904,7 @@ __cpufreq_cooling_register(struct device_node *np, CPUFREQ_POLICY_NOTIFIER); mutex_unlock(&cooling_cpufreq_lock); - return cool_dev; + goto put_policy; remove_idr: release_idr(&cpufreq_idr, cpufreq_dev->id); @@ -906,6 +918,8 @@ __cpufreq_cooling_register(struct device_node *np, kfree(cpufreq_dev->time_in_idle); free_cdev: kfree(cpufreq_dev); +put_policy: + cpufreq_cpu_put(policy); return cool_dev; } diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index 7ed93c310c08..1342cbc0f25e 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -632,8 +632,6 @@ static inline bool policy_has_boost_freq(struct cpufreq_policy *policy) return false; } #endif -/* the following funtion is for cpufreq core use only */ -struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu); /* the following are really really optional */ extern struct freq_attr cpufreq_freq_attr_scaling_available_freqs; -- 2.7.1.410.g6faf27b