From ab05d97a3785088fa2964219227a1ba95d97d590 Mon Sep 17 00:00:00 2001 From: Yue Hu Date: Mon, 29 Apr 2019 15:24:18 +0800 Subject: [PATCH] cpufreq: Don't find governor for setpolicy drivers in cpufreq_init_policy() In cpufreq_init_policy() we will check if there's last_governor for target and setpolicy type. However last_governor is set only if has_target() is true in cpufreq_offline(). That means find last_governor for setpolicy type is pointless. Also new_policy.governor will not be used if ->setpolicy callback is set in cpufreq_set_policy(). Moreover, there's duplicate ->setpolicy check in using default policy path. Let's add a new helper function to avoid it. Also update comments. Signed-off-by: Yue Hu Acked-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/cpufreq.c | 118 +++++++++++++++++++++----------------- 1 file changed, 66 insertions(+), 52 deletions(-) diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 57a3853a55fb..f941efd9b836 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -619,50 +619,52 @@ static struct cpufreq_governor *find_governor(const char *str_governor) return NULL; } +static int cpufreq_parse_policy(char *str_governor, + struct cpufreq_policy *policy) +{ + if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) { + policy->policy = CPUFREQ_POLICY_PERFORMANCE; + return 0; + } + if (!strncasecmp(str_governor, "powersave", CPUFREQ_NAME_LEN)) { + policy->policy = CPUFREQ_POLICY_POWERSAVE; + return 0; + } + return -EINVAL; +} + /** - * cpufreq_parse_governor - parse a governor string + * cpufreq_parse_governor - parse a governor string only for !setpolicy */ static int cpufreq_parse_governor(char *str_governor, struct cpufreq_policy *policy) { - if (cpufreq_driver->setpolicy) { - if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) { - policy->policy = CPUFREQ_POLICY_PERFORMANCE; - return 0; - } + struct cpufreq_governor *t; - if (!strncasecmp(str_governor, "powersave", CPUFREQ_NAME_LEN)) { - policy->policy = CPUFREQ_POLICY_POWERSAVE; - return 0; - } - } else { - struct cpufreq_governor *t; + mutex_lock(&cpufreq_governor_mutex); + + t = find_governor(str_governor); + if (!t) { + int ret; + + mutex_unlock(&cpufreq_governor_mutex); + + ret = request_module("cpufreq_%s", str_governor); + if (ret) + return -EINVAL; mutex_lock(&cpufreq_governor_mutex); t = find_governor(str_governor); - if (!t) { - int ret; + } + if (t && !try_module_get(t->owner)) + t = NULL; - mutex_unlock(&cpufreq_governor_mutex); + mutex_unlock(&cpufreq_governor_mutex); - ret = request_module("cpufreq_%s", str_governor); - if (ret) - return -EINVAL; - - mutex_lock(&cpufreq_governor_mutex); - - t = find_governor(str_governor); - } - if (t && !try_module_get(t->owner)) - t = NULL; - - mutex_unlock(&cpufreq_governor_mutex); - - if (t) { - policy->governor = t; - return 0; - } + if (t) { + policy->governor = t; + return 0; } return -EINVAL; @@ -784,8 +786,13 @@ static ssize_t store_scaling_governor(struct cpufreq_policy *policy, if (ret != 1) return -EINVAL; - if (cpufreq_parse_governor(str_governor, &new_policy)) - return -EINVAL; + if (cpufreq_driver->setpolicy) { + if (cpufreq_parse_policy(str_governor, &new_policy)) + return -EINVAL; + } else { + if (cpufreq_parse_governor(str_governor, &new_policy)) + return -EINVAL; + } ret = cpufreq_set_policy(policy, &new_policy); @@ -1051,32 +1058,39 @@ __weak struct cpufreq_governor *cpufreq_default_governor(void) static int cpufreq_init_policy(struct cpufreq_policy *policy) { - struct cpufreq_governor *gov = NULL; + struct cpufreq_governor *gov = NULL, *def_gov = NULL; struct cpufreq_policy new_policy; memcpy(&new_policy, policy, sizeof(*policy)); - /* Update governor of new_policy to the governor used before hotplug */ - gov = find_governor(policy->last_governor); - if (gov) { - pr_debug("Restoring governor %s for cpu %d\n", + def_gov = cpufreq_default_governor(); + + if (has_target()) { + /* + * Update governor of new_policy to the governor used before + * hotplug + */ + gov = find_governor(policy->last_governor); + if (gov) { + pr_debug("Restoring governor %s for cpu %d\n", policy->governor->name, policy->cpu); + } else { + if (!def_gov) + return -ENODATA; + gov = def_gov; + } + new_policy.governor = gov; } else { - gov = cpufreq_default_governor(); - if (!gov) - return -ENODATA; - } - - new_policy.governor = gov; - - /* Use the default policy if there is no last_policy. */ - if (cpufreq_driver->setpolicy) { - if (policy->last_policy) + /* Use the default policy if there is no last_policy. */ + if (policy->last_policy) { new_policy.policy = policy->last_policy; - else - cpufreq_parse_governor(gov->name, &new_policy); + } else { + if (!def_gov) + return -ENODATA; + cpufreq_parse_policy(def_gov->name, &new_policy); + } } - /* set default policy */ + return cpufreq_set_policy(policy, &new_policy); }