From cffe4e0e7413eb29fb8bd035c8b12b33a4b8522a Mon Sep 17 00:00:00 2001 From: Stratos Karafotis Date: Wed, 5 Jun 2013 19:01:50 +0300 Subject: cpufreq: Remove unused function __cpufreq_driver_getavg() The target frequency calculation method in the ondemand governor has changed and it is now independent of the measured average frequency. Consequently, the __cpufreq_driver_getavg() function and getavg member of struct cpufreq_driver are not used any more, so drop them. [rjw: Changelog] Signed-off-by: Stratos Karafotis Acked-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- include/linux/cpufreq.h | 6 ------ 1 file changed, 6 deletions(-) (limited to 'include/linux/cpufreq.h') diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index 90d5a15120d5..e1fd215e16c9 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -216,10 +216,6 @@ extern int cpufreq_driver_target(struct cpufreq_policy *policy, extern int __cpufreq_driver_target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation); - -extern int __cpufreq_driver_getavg(struct cpufreq_policy *policy, - unsigned int cpu); - int cpufreq_register_governor(struct cpufreq_governor *governor); void cpufreq_unregister_governor(struct cpufreq_governor *governor); @@ -258,8 +254,6 @@ struct cpufreq_driver { unsigned int (*get) (unsigned int cpu); /* optional */ - unsigned int (*getavg) (struct cpufreq_policy *policy, - unsigned int cpu); int (*bios_limit) (int cpu, unsigned int *limit); int (*exit) (struct cpufreq_policy *policy); -- cgit v1.2.3 From 5ff0a268037d344f86df690ccb994d8bc015d2d9 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Tue, 6 Aug 2013 22:53:03 +0530 Subject: cpufreq: Clean up header files included in the core This patch addresses the following issues in the header files in the cpufreq core: - Include headers in ascending order, so that we don't add same many times by mistake. - must be included after , so that they override whatever they need to. - Remove unnecessary includes. - Don't include files already included by cpufreq.h or cpufreq_governor.h. [rjw: Changelog] Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- include/linux/cpufreq.h | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) (limited to 'include/linux/cpufreq.h') diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index e1fd215e16c9..97627bbbca82 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -11,16 +11,11 @@ #ifndef _LINUX_CPUFREQ_H #define _LINUX_CPUFREQ_H -#include -#include -#include -#include +#include +#include #include +#include #include -#include -#include -#include -#include #define CPUFREQ_NAME_LEN 16 /* Print length for names. Extra 1 space for accomodating '\n' in prints */ -- cgit v1.2.3 From 74aca95da74836a6807118f6590d8df8232c74a9 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Tue, 6 Aug 2013 22:53:04 +0530 Subject: cpufreq: Re-arrange declarations in cpufreq.h They are pretty much mixed up. Although generic headers are present, definitions/declarations are present outside of them too ... This patch just moves stuff up and down to make it look better and consistent. Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- include/linux/cpufreq.h | 373 +++++++++++++++++++++++------------------------- 1 file changed, 177 insertions(+), 196 deletions(-) (limited to 'include/linux/cpufreq.h') diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index 97627bbbca82..0d3b0266bc98 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -17,60 +17,30 @@ #include #include -#define CPUFREQ_NAME_LEN 16 -/* Print length for names. Extra 1 space for accomodating '\n' in prints */ -#define CPUFREQ_NAME_PLEN (CPUFREQ_NAME_LEN + 1) - /********************************************************************* - * CPUFREQ NOTIFIER INTERFACE * + * CPUFREQ INTERFACE * *********************************************************************/ - -#define CPUFREQ_TRANSITION_NOTIFIER (0) -#define CPUFREQ_POLICY_NOTIFIER (1) - -#ifdef CONFIG_CPU_FREQ -int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list); -int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list); -extern void disable_cpufreq(void); -#else /* CONFIG_CPU_FREQ */ -static inline int cpufreq_register_notifier(struct notifier_block *nb, - unsigned int list) -{ - return 0; -} -static inline int cpufreq_unregister_notifier(struct notifier_block *nb, - unsigned int list) -{ - return 0; -} -static inline void disable_cpufreq(void) { } -#endif /* CONFIG_CPU_FREQ */ - -/* if (cpufreq_driver->target) exists, the ->governor decides what frequency - * within the limits is used. If (cpufreq_driver->setpolicy> exists, these - * two generic policies are available: - */ - -#define CPUFREQ_POLICY_POWERSAVE (1) -#define CPUFREQ_POLICY_PERFORMANCE (2) - -/* Frequency values here are CPU kHz so that hardware which doesn't run - * with some frequencies can complain without having to guess what per - * cent / per mille means. +/* + * Frequency values here are CPU kHz + * * Maximum transition latency is in nanoseconds - if it's unknown, * CPUFREQ_ETERNAL shall be used. */ +#define CPUFREQ_ETERNAL (-1) +#define CPUFREQ_NAME_LEN 16 +/* Print length for names. Extra 1 space for accomodating '\n' in prints */ +#define CPUFREQ_NAME_PLEN (CPUFREQ_NAME_LEN + 1) + struct cpufreq_governor; -/* /sys/devices/system/cpu/cpufreq: entry point for global variables */ -extern struct kobject *cpufreq_global_kobject; -int cpufreq_get_global_kobject(void); -void cpufreq_put_global_kobject(void); -int cpufreq_sysfs_create_file(const struct attribute *attr); -void cpufreq_sysfs_remove_file(const struct attribute *attr); +struct cpufreq_freqs { + unsigned int cpu; /* cpu nr */ + unsigned int old; + unsigned int new; + u8 flags; /* flags of cpufreq_driver, see below. */ +}; -#define CPUFREQ_ETERNAL (-1) struct cpufreq_cpuinfo { unsigned int max_freq; unsigned int min_freq; @@ -117,111 +87,95 @@ struct cpufreq_policy { int transition_ongoing; /* Tracks transition status */ }; -#define CPUFREQ_ADJUST (0) -#define CPUFREQ_INCOMPATIBLE (1) -#define CPUFREQ_NOTIFY (2) -#define CPUFREQ_START (3) -#define CPUFREQ_UPDATE_POLICY_CPU (4) - /* Only for ACPI */ #define CPUFREQ_SHARED_TYPE_NONE (0) /* None */ #define CPUFREQ_SHARED_TYPE_HW (1) /* HW does needed coordination */ #define CPUFREQ_SHARED_TYPE_ALL (2) /* All dependent CPUs should set freq */ #define CPUFREQ_SHARED_TYPE_ANY (3) /* Freq can be set from any dependent CPU*/ +struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu); +void cpufreq_cpu_put(struct cpufreq_policy *data); + static inline bool policy_is_shared(struct cpufreq_policy *policy) { return cpumask_weight(policy->cpus) > 1; } -/******************** cpufreq transition notifiers *******************/ - -#define CPUFREQ_PRECHANGE (0) -#define CPUFREQ_POSTCHANGE (1) -#define CPUFREQ_RESUMECHANGE (8) -#define CPUFREQ_SUSPENDCHANGE (9) +/* /sys/devices/system/cpu/cpufreq: entry point for global variables */ +extern struct kobject *cpufreq_global_kobject; +int cpufreq_get_global_kobject(void); +void cpufreq_put_global_kobject(void); +int cpufreq_sysfs_create_file(const struct attribute *attr); +void cpufreq_sysfs_remove_file(const struct attribute *attr); -struct cpufreq_freqs { - unsigned int cpu; /* cpu nr */ - unsigned int old; - unsigned int new; - u8 flags; /* flags of cpufreq_driver, see below. */ -}; +#ifdef CONFIG_CPU_FREQ +unsigned int cpufreq_get(unsigned int cpu); +unsigned int cpufreq_quick_get(unsigned int cpu); +unsigned int cpufreq_quick_get_max(unsigned int cpu); +void disable_cpufreq(void); -/** - * cpufreq_scale - "old * mult / div" calculation for large values (32-bit-arch - * safe) - * @old: old value - * @div: divisor - * @mult: multiplier - * - * - * new = old * mult / div - */ -static inline unsigned long cpufreq_scale(unsigned long old, u_int div, - u_int mult) +u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy); +int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu); +int cpufreq_update_policy(unsigned int cpu); +bool have_governor_per_policy(void); +struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy); +#else +static inline unsigned int cpufreq_get(unsigned int cpu) { -#if BITS_PER_LONG == 32 - - u64 result = ((u64) old) * ((u64) mult); - do_div(result, div); - return (unsigned long) result; - -#elif BITS_PER_LONG == 64 - - unsigned long result = old * ((u64) mult); - result /= div; - return result; - + return 0; +} +static inline unsigned int cpufreq_quick_get(unsigned int cpu) +{ + return 0; +} +static inline unsigned int cpufreq_quick_get_max(unsigned int cpu) +{ + return 0; +} +static inline void disable_cpufreq(void) { } #endif -}; /********************************************************************* - * CPUFREQ GOVERNORS * + * CPUFREQ DRIVER INTERFACE * *********************************************************************/ -#define CPUFREQ_GOV_START 1 -#define CPUFREQ_GOV_STOP 2 -#define CPUFREQ_GOV_LIMITS 3 -#define CPUFREQ_GOV_POLICY_INIT 4 -#define CPUFREQ_GOV_POLICY_EXIT 5 +#define CPUFREQ_RELATION_L 0 /* lowest frequency at or above target */ +#define CPUFREQ_RELATION_H 1 /* highest frequency below or at target */ -struct cpufreq_governor { - char name[CPUFREQ_NAME_LEN]; - int initialized; - int (*governor) (struct cpufreq_policy *policy, - unsigned int event); - ssize_t (*show_setspeed) (struct cpufreq_policy *policy, - char *buf); - int (*store_setspeed) (struct cpufreq_policy *policy, - unsigned int freq); - unsigned int max_transition_latency; /* HW must be able to switch to - next freq faster than this value in nano secs or we - will fallback to performance governor */ - struct list_head governor_list; - struct module *owner; +struct freq_attr { + struct attribute attr; + ssize_t (*show)(struct cpufreq_policy *, char *); + ssize_t (*store)(struct cpufreq_policy *, const char *, size_t count); }; -/* - * Pass a target to the cpufreq driver. - */ -extern int cpufreq_driver_target(struct cpufreq_policy *policy, - unsigned int target_freq, - unsigned int relation); -extern int __cpufreq_driver_target(struct cpufreq_policy *policy, - unsigned int target_freq, - unsigned int relation); -int cpufreq_register_governor(struct cpufreq_governor *governor); -void cpufreq_unregister_governor(struct cpufreq_governor *governor); +#define cpufreq_freq_attr_ro(_name) \ +static struct freq_attr _name = \ +__ATTR(_name, 0444, show_##_name, NULL) -/********************************************************************* - * CPUFREQ DRIVER INTERFACE * - *********************************************************************/ +#define cpufreq_freq_attr_ro_perm(_name, _perm) \ +static struct freq_attr _name = \ +__ATTR(_name, _perm, show_##_name, NULL) -#define CPUFREQ_RELATION_L 0 /* lowest frequency at or above target */ -#define CPUFREQ_RELATION_H 1 /* highest frequency below or at target */ +#define cpufreq_freq_attr_rw(_name) \ +static struct freq_attr _name = \ +__ATTR(_name, 0644, show_##_name, store_##_name) + +struct global_attr { + struct attribute attr; + ssize_t (*show)(struct kobject *kobj, + struct attribute *attr, char *buf); + ssize_t (*store)(struct kobject *a, struct attribute *b, + const char *c, size_t count); +}; + +#define define_one_global_ro(_name) \ +static struct global_attr _name = \ +__ATTR(_name, 0444, show_##_name, NULL) + +#define define_one_global_rw(_name) \ +static struct global_attr _name = \ +__ATTR(_name, 0644, show_##_name, store_##_name) -struct freq_attr; struct cpufreq_driver { struct module *owner; @@ -258,7 +212,6 @@ struct cpufreq_driver { }; /* flags */ - #define CPUFREQ_STICKY 0x01 /* the driver isn't removed even if * all ->init() calls failed */ #define CPUFREQ_CONST_LOOPS 0x02 /* loops_per_jiffy or other kernel @@ -270,8 +223,7 @@ struct cpufreq_driver { int cpufreq_register_driver(struct cpufreq_driver *driver_data); int cpufreq_unregister_driver(struct cpufreq_driver *driver_data); -void cpufreq_notify_transition(struct cpufreq_policy *policy, - struct cpufreq_freqs *freqs, unsigned int state); +const char *cpufreq_get_current_driver(void); static inline void cpufreq_verify_within_limits(struct cpufreq_policy *policy, unsigned int min, unsigned int max) @@ -289,86 +241,117 @@ static inline void cpufreq_verify_within_limits(struct cpufreq_policy *policy, return; } -struct freq_attr { - struct attribute attr; - ssize_t (*show)(struct cpufreq_policy *, char *); - ssize_t (*store)(struct cpufreq_policy *, const char *, size_t count); -}; - -#define cpufreq_freq_attr_ro(_name) \ -static struct freq_attr _name = \ -__ATTR(_name, 0444, show_##_name, NULL) - -#define cpufreq_freq_attr_ro_perm(_name, _perm) \ -static struct freq_attr _name = \ -__ATTR(_name, _perm, show_##_name, NULL) - -#define cpufreq_freq_attr_rw(_name) \ -static struct freq_attr _name = \ -__ATTR(_name, 0644, show_##_name, store_##_name) +/********************************************************************* + * CPUFREQ NOTIFIER INTERFACE * + *********************************************************************/ -struct global_attr { - struct attribute attr; - ssize_t (*show)(struct kobject *kobj, - struct attribute *attr, char *buf); - ssize_t (*store)(struct kobject *a, struct attribute *b, - const char *c, size_t count); -}; +#define CPUFREQ_TRANSITION_NOTIFIER (0) +#define CPUFREQ_POLICY_NOTIFIER (1) -#define define_one_global_ro(_name) \ -static struct global_attr _name = \ -__ATTR(_name, 0444, show_##_name, NULL) +/* Transition notifiers */ +#define CPUFREQ_PRECHANGE (0) +#define CPUFREQ_POSTCHANGE (1) +#define CPUFREQ_RESUMECHANGE (8) +#define CPUFREQ_SUSPENDCHANGE (9) -#define define_one_global_rw(_name) \ -static struct global_attr _name = \ -__ATTR(_name, 0644, show_##_name, store_##_name) +/* Policy Notifiers */ +#define CPUFREQ_ADJUST (0) +#define CPUFREQ_INCOMPATIBLE (1) +#define CPUFREQ_NOTIFY (2) +#define CPUFREQ_START (3) +#define CPUFREQ_UPDATE_POLICY_CPU (4) -struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu); -void cpufreq_cpu_put(struct cpufreq_policy *data); -const char *cpufreq_get_current_driver(void); +#ifdef CONFIG_CPU_FREQ +int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list); +int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list); -/********************************************************************* - * CPUFREQ 2.6. INTERFACE * - *********************************************************************/ -u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy); -int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu); -int cpufreq_update_policy(unsigned int cpu); -bool have_governor_per_policy(void); -struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy); +void cpufreq_notify_transition(struct cpufreq_policy *policy, + struct cpufreq_freqs *freqs, unsigned int state); -#ifdef CONFIG_CPU_FREQ -/* - * query the current CPU frequency (in kHz). If zero, cpufreq couldn't detect it - */ -unsigned int cpufreq_get(unsigned int cpu); -#else -static inline unsigned int cpufreq_get(unsigned int cpu) +#else /* CONFIG_CPU_FREQ */ +static inline int cpufreq_register_notifier(struct notifier_block *nb, + unsigned int list) { return 0; } -#endif - -/* - * query the last known CPU freq (in kHz). If zero, cpufreq couldn't detect it - */ -#ifdef CONFIG_CPU_FREQ -unsigned int cpufreq_quick_get(unsigned int cpu); -unsigned int cpufreq_quick_get_max(unsigned int cpu); -#else -static inline unsigned int cpufreq_quick_get(unsigned int cpu) +static inline int cpufreq_unregister_notifier(struct notifier_block *nb, + unsigned int list) { return 0; } -static inline unsigned int cpufreq_quick_get_max(unsigned int cpu) +#endif /* !CONFIG_CPU_FREQ */ + +/** + * cpufreq_scale - "old * mult / div" calculation for large values (32-bit-arch + * safe) + * @old: old value + * @div: divisor + * @mult: multiplier + * + * + * new = old * mult / div + */ +static inline unsigned long cpufreq_scale(unsigned long old, u_int div, + u_int mult) { - return 0; -} +#if BITS_PER_LONG == 32 + u64 result = ((u64) old) * ((u64) mult); + do_div(result, div); + return (unsigned long) result; + +#elif BITS_PER_LONG == 64 + unsigned long result = old * ((u64) mult); + result /= div; + return result; #endif +} /********************************************************************* - * CPUFREQ DEFAULT GOVERNOR * + * CPUFREQ GOVERNORS * *********************************************************************/ +/* + * If (cpufreq_driver->target) exists, the ->governor decides what frequency + * within the limits is used. If (cpufreq_driver->setpolicy> exists, these + * two generic policies are available: + */ +#define CPUFREQ_POLICY_POWERSAVE (1) +#define CPUFREQ_POLICY_PERFORMANCE (2) + +/* Governor Events */ +#define CPUFREQ_GOV_START 1 +#define CPUFREQ_GOV_STOP 2 +#define CPUFREQ_GOV_LIMITS 3 +#define CPUFREQ_GOV_POLICY_INIT 4 +#define CPUFREQ_GOV_POLICY_EXIT 5 + +struct cpufreq_governor { + char name[CPUFREQ_NAME_LEN]; + int initialized; + int (*governor) (struct cpufreq_policy *policy, + unsigned int event); + ssize_t (*show_setspeed) (struct cpufreq_policy *policy, + char *buf); + int (*store_setspeed) (struct cpufreq_policy *policy, + unsigned int freq); + unsigned int max_transition_latency; /* HW must be able to switch to + next freq faster than this value in nano secs or we + will fallback to performance governor */ + struct list_head governor_list; + struct module *owner; +}; + +/* Pass a target to the cpufreq driver */ +int cpufreq_driver_target(struct cpufreq_policy *policy, + unsigned int target_freq, + unsigned int relation); +int __cpufreq_driver_target(struct cpufreq_policy *policy, + unsigned int target_freq, + unsigned int relation); +int cpufreq_register_governor(struct cpufreq_governor *governor); +void cpufreq_unregister_governor(struct cpufreq_governor *governor); + +/* CPUFREQ DEFAULT GOVERNOR */ /* * Performance governor is fallback governor if any other gov failed to auto * load due latency restrictions @@ -417,18 +400,16 @@ int cpufreq_frequency_table_target(struct cpufreq_policy *policy, unsigned int relation, unsigned int *index); -/* the following 3 funtions are for cpufreq core use only */ +void cpufreq_frequency_table_update_policy_cpu(struct cpufreq_policy *policy); +ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf); + +/* 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; - void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table, unsigned int cpu); -void cpufreq_frequency_table_update_policy_cpu(struct cpufreq_policy *policy); - void cpufreq_frequency_table_put_attr(unsigned int cpu); -ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf); - #endif /* _LINUX_CPUFREQ_H */ -- cgit v1.2.3 From 3a3e9e06d0c11b8efa95933a88c9e67209fa4330 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Tue, 6 Aug 2013 22:53:05 +0530 Subject: cpufreq: Give consistent names to cpufreq_policy objects They are called policy, cur_policy, new_policy, data, etc. Just call them policy wherever possible. Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- include/linux/cpufreq.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/cpufreq.h') diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index 0d3b0266bc98..29208923c9d3 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -94,7 +94,7 @@ struct cpufreq_policy { #define CPUFREQ_SHARED_TYPE_ANY (3) /* Freq can be set from any dependent CPU*/ struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu); -void cpufreq_cpu_put(struct cpufreq_policy *data); +void cpufreq_cpu_put(struct cpufreq_policy *policy); static inline bool policy_is_shared(struct cpufreq_policy *policy) { -- cgit v1.2.3 From c88a1f8b96e7384627b918dfabbfc0c615a4a914 Mon Sep 17 00:00:00 2001 From: Lukasz Majewski Date: Tue, 6 Aug 2013 22:53:08 +0530 Subject: cpufreq: Store cpufreq policies in a list Policies available in the cpufreq framework are now linked together. They are accessible via cpufreq_policy_list defined in the cpufreq core. [rjw: Fix from Yinghai Lu folded in] Signed-off-by: Lukasz Majewski Signed-off-by: Myungjoo Ham Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- include/linux/cpufreq.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/cpufreq.h') diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index 29208923c9d3..431a05d4b4c9 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -82,6 +82,7 @@ struct cpufreq_policy { struct cpufreq_real_policy user_policy; + struct list_head policy_list; struct kobject kobj; struct completion kobj_unregister; int transition_ongoing; /* Tracks transition status */ -- cgit v1.2.3 From adc97d6a735dbb1e94cb4f1bf0b55f258b349941 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Tue, 6 Aug 2013 22:53:12 +0530 Subject: cpufreq: Drop the owner field from struct cpufreq_driver We don't need to set .owner = THIS_MODULE any more in cpufreq drivers as this field isn't used any more by the cpufreq core. This patch removes it and updates all dependent drivers accordingly. Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- include/linux/cpufreq.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include/linux/cpufreq.h') diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index 431a05d4b4c9..d568f3975eeb 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -179,7 +179,6 @@ __ATTR(_name, 0644, show_##_name, store_##_name) struct cpufreq_driver { - struct module *owner; char name[CPUFREQ_NAME_LEN]; u8 flags; /* -- cgit v1.2.3 From 19c763031acb831a5ab9c1a701b7fedda073eb3f Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Sat, 31 Aug 2013 17:48:23 +0530 Subject: cpufreq: serialize calls to __cpufreq_governor() We can't take a big lock around __cpufreq_governor() as this causes recursive locking for some cases. But calls to this routine must be serialized for every policy. Otherwise we can see some unpredictable events. For example, consider following scenario: __cpufreq_remove_dev() __cpufreq_governor(policy, CPUFREQ_GOV_STOP); policy->governor->governor(policy, CPUFREQ_GOV_STOP); cpufreq_governor_dbs() case CPUFREQ_GOV_STOP: mutex_destroy(&cpu_cdbs->timer_mutex) cpu_cdbs->cur_policy = NULL; store() __cpufreq_set_policy() __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); policy->governor->governor(policy, CPUFREQ_GOV_LIMITS); case CPUFREQ_GOV_LIMITS: mutex_lock(&cpu_cdbs->timer_mutex); <-- Warning (destroyed mutex) if (policy->max < cpu_cdbs->cur_policy->cur) <- cur_policy == NULL And so store() will eventually result in a crash if cur_policy is NULL at this point. Introduce an additional variable which would guarantee serialization here. Reported-by: Stephen Boyd Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- include/linux/cpufreq.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/cpufreq.h') diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index d568f3975eeb..cca885dac1d3 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -76,6 +76,7 @@ struct cpufreq_policy { struct cpufreq_governor *governor; /* see below */ void *governor_data; bool governor_enabled; /* governor start/stop flag */ + bool governor_busy; struct work_struct update; /* if update_policy() needs to be * called, but you're in IRQ context */ -- cgit v1.2.3 From 56d07db274b7b15ca38b60ea4a762d40de093000 Mon Sep 17 00:00:00 2001 From: "Srivatsa S. Bhat" Date: Sat, 7 Sep 2013 01:23:55 +0530 Subject: cpufreq: Remove temporary fix for race between CPU hotplug and sysfs-writes Commit "cpufreq: serialize calls to __cpufreq_governor()" had been a temporary and partial solution to the race condition between writing to a cpufreq sysfs file and taking a CPU offline. Now that we have a proper and complete solution to that problem, remove the temporary fix. Signed-off-by: Srivatsa S. Bhat Signed-off-by: Rafael J. Wysocki --- include/linux/cpufreq.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include/linux/cpufreq.h') diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index cca885dac1d3..d568f3975eeb 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -76,7 +76,6 @@ struct cpufreq_policy { struct cpufreq_governor *governor; /* see below */ void *governor_data; bool governor_enabled; /* governor start/stop flag */ - bool governor_busy; struct work_struct update; /* if update_policy() needs to be * called, but you're in IRQ context */ -- cgit v1.2.3 From 798282a8718347b04a2f0a4bae7d775c48c6bcb9 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 10 Sep 2013 02:54:50 +0200 Subject: Revert "cpufreq: make sure frequency transitions are serialized" Commit 7c30ed5 (cpufreq: make sure frequency transitions are serialized) attempted to serialize frequency transitions by adding checks to the CPUFREQ_PRECHANGE and CPUFREQ_POSTCHANGE notifications. However, it assumed that the notifications will always originate from the driver's .target() callback, but they also can be triggered by cpufreq_out_of_sync() and that leads to warnings like this on some systems: WARNING: CPU: 0 PID: 14543 at drivers/cpufreq/cpufreq.c:317 __cpufreq_notify_transition+0x238/0x260() In middle of another frequency transition accompanied by a call trace similar to this one: [] dump_stack+0x46/0x58 [] warn_slowpath_common+0x8c/0xc0 [] ? acpi_cpufreq_target+0x320/0x320 [] warn_slowpath_fmt+0x46/0x50 [] __cpufreq_notify_transition+0x238/0x260 [] cpufreq_notify_transition+0x3e/0x70 [] cpufreq_out_of_sync+0x6d/0xb0 [] cpufreq_update_policy+0x10c/0x160 [] ? cpufreq_update_policy+0x160/0x160 [] cpufreq_set_cur_state+0x8c/0xb5 [] processor_set_cur_state+0xa3/0xcf [] thermal_cdev_update+0x9c/0xb0 [] step_wise_throttle+0x5a/0x90 [] handle_thermal_trip+0x4f/0x140 [] thermal_zone_device_update+0x57/0xa0 [] acpi_thermal_check+0x2e/0x30 [] acpi_thermal_notify+0x40/0xdc [] acpi_device_notify+0x19/0x1b [] acpi_ev_notify_dispatch+0x41/0x5c [] acpi_os_execute_deferred+0x25/0x32 [] process_one_work+0x170/0x4a0 [] worker_thread+0x121/0x390 [] ? manage_workers.isra.20+0x170/0x170 [] kthread+0xc0/0xd0 [] ? flush_kthread_worker+0xb0/0xb0 [] ret_from_fork+0x7c/0xb0 [] ? flush_kthread_worker+0xb0/0xb0 For this reason, revert commit 7c30ed5 along with the fix 266c13d (cpufreq: Fix serialization of frequency transitions) on top of it and we will revisit the serialization problem later. Reported-by: Alessandro Bono Signed-off-by: Rafael J. Wysocki --- include/linux/cpufreq.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include/linux/cpufreq.h') diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index d568f3975eeb..fcabc42d66ab 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -85,7 +85,6 @@ struct cpufreq_policy { struct list_head policy_list; struct kobject kobj; struct completion kobj_unregister; - int transition_ongoing; /* Tracks transition status */ }; /* Only for ACPI */ -- cgit v1.2.3