From a92604b419f47e1c5098632742d8e031f6e8fab1 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sat, 14 May 2016 01:01:46 +0200 Subject: [PATCH] cpufreq: Split cpufreq_governor() into simpler functions The cpufreq_governor() routine is used by the cpufreq core to invoke the current governor's ->governor() callback with appropriate arguments and do some housekeeping related to that. Unfortunately, the way it mixes different governor events in one code path makes it rather hard to follow the code. For this reason, split cpufreq_governor() into five simpler functions that each will handle just one specific governor event and put all of the code related to the given event into its own function. This change is a prerequisite for a redesign of the cpufreq governor API that will be done subsequently. Signed-off-by: Rafael J. Wysocki Acked-by: Viresh Kumar --- drivers/cpufreq/cpufreq.c | 113 +++++++++++++++++++++++--------------- 1 file changed, 70 insertions(+), 43 deletions(-) diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index a5f1d016d473..268566e40684 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -74,19 +74,12 @@ static inline bool has_target(void) } /* internal prototypes */ -static int cpufreq_governor(struct cpufreq_policy *policy, unsigned int event); static unsigned int __cpufreq_get(struct cpufreq_policy *policy); +static int cpufreq_init_governor(struct cpufreq_policy *policy); +static void cpufreq_exit_governor(struct cpufreq_policy *policy); static int cpufreq_start_governor(struct cpufreq_policy *policy); - -static inline void cpufreq_exit_governor(struct cpufreq_policy *policy) -{ - (void)cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); -} - -static inline void cpufreq_stop_governor(struct cpufreq_policy *policy) -{ - (void)cpufreq_governor(policy, CPUFREQ_GOV_STOP); -} +static void cpufreq_stop_governor(struct cpufreq_policy *policy); +static void cpufreq_governor_limits(struct cpufreq_policy *policy); /** * Two notifier lists: the "policy" list is involved in the @@ -1997,7 +1990,7 @@ __weak struct cpufreq_governor *cpufreq_fallback_governor(void) return NULL; } -static int cpufreq_governor(struct cpufreq_policy *policy, unsigned int event) +static int cpufreq_init_governor(struct cpufreq_policy *policy) { int ret; @@ -2011,57 +2004,91 @@ static int cpufreq_governor(struct cpufreq_policy *policy, unsigned int event) if (!policy->governor) return -EINVAL; - if (event == CPUFREQ_GOV_POLICY_INIT) { - if (policy->governor->max_transition_latency && - policy->cpuinfo.transition_latency > - policy->governor->max_transition_latency) { - struct cpufreq_governor *gov = cpufreq_fallback_governor(); - - if (gov) { - pr_warn("%s governor failed, too long transition latency of HW, fallback to %s governor\n", - policy->governor->name, gov->name); - policy->governor = gov; - } else { - return -EINVAL; - } - } + if (policy->governor->max_transition_latency && + policy->cpuinfo.transition_latency > + policy->governor->max_transition_latency) { + struct cpufreq_governor *gov = cpufreq_fallback_governor(); - if (!try_module_get(policy->governor->owner)) + if (gov) { + pr_warn("%s governor failed, too long transition latency of HW, fallback to %s governor\n", + policy->governor->name, gov->name); + policy->governor = gov; + } else { return -EINVAL; + } } - pr_debug("%s: for CPU %u, event %u\n", __func__, policy->cpu, event); + if (!try_module_get(policy->governor->owner)) + return -EINVAL; - ret = policy->governor->governor(policy, event); + pr_debug("%s: for CPU %u\n", __func__, policy->cpu); - if (event == CPUFREQ_GOV_POLICY_INIT) { - if (ret) - module_put(policy->governor->owner); - else - policy->governor->initialized++; - } else if (event == CPUFREQ_GOV_POLICY_EXIT) { - policy->governor->initialized--; + ret = policy->governor->governor(policy, CPUFREQ_GOV_POLICY_INIT); + if (ret) { module_put(policy->governor->owner); + return ret; } - return ret; + policy->governor->initialized++; + return 0; +} + +static void cpufreq_exit_governor(struct cpufreq_policy *policy) +{ + if (cpufreq_suspended || !policy->governor) + return; + + pr_debug("%s: for CPU %u\n", __func__, policy->cpu); + + policy->governor->governor(policy, CPUFREQ_GOV_POLICY_EXIT); + + policy->governor->initialized--; + module_put(policy->governor->owner); } static int cpufreq_start_governor(struct cpufreq_policy *policy) { int ret; + if (cpufreq_suspended) + return 0; + + if (!policy->governor) + return -EINVAL; + + pr_debug("%s: for CPU %u\n", __func__, policy->cpu); + if (cpufreq_driver->get && !cpufreq_driver->setpolicy) cpufreq_update_current_freq(policy); - ret = cpufreq_governor(policy, CPUFREQ_GOV_START); + ret = policy->governor->governor(policy, CPUFREQ_GOV_START); if (ret) return ret; - cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); + policy->governor->governor(policy, CPUFREQ_GOV_LIMITS); return 0; } +static void cpufreq_stop_governor(struct cpufreq_policy *policy) +{ + if (cpufreq_suspended || !policy->governor) + return; + + pr_debug("%s: for CPU %u\n", __func__, policy->cpu); + + policy->governor->governor(policy, CPUFREQ_GOV_STOP); +} + +static void cpufreq_governor_limits(struct cpufreq_policy *policy) +{ + if (cpufreq_suspended || !policy->governor) + return; + + pr_debug("%s: for CPU %u\n", __func__, policy->cpu); + + policy->governor->governor(policy, CPUFREQ_GOV_LIMITS); +} + int cpufreq_register_governor(struct cpufreq_governor *governor) { int err; @@ -2200,7 +2227,7 @@ static int cpufreq_set_policy(struct cpufreq_policy *policy, if (new_policy->governor == policy->governor) { pr_debug("cpufreq: governor limits update\n"); - cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); + cpufreq_governor_limits(policy); return 0; } @@ -2216,7 +2243,7 @@ static int cpufreq_set_policy(struct cpufreq_policy *policy, /* start new governor */ policy->governor = new_policy->governor; - ret = cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT); + ret = cpufreq_init_governor(policy); if (!ret) { ret = cpufreq_start_governor(policy); if (!ret) { @@ -2230,7 +2257,7 @@ static int cpufreq_set_policy(struct cpufreq_policy *policy, pr_debug("starting governor %s failed\n", policy->governor->name); if (old_gov) { policy->governor = old_gov; - if (cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT)) + if (cpufreq_init_governor(policy)) policy->governor = NULL; else cpufreq_start_governor(policy); @@ -2328,7 +2355,7 @@ static int cpufreq_boost_set_sw(int state) down_write(&policy->rwsem); policy->user_policy.max = policy->max; - cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); + cpufreq_governor_limits(policy); up_write(&policy->rwsem); } } -- 2.20.1