diff options
| -rw-r--r-- | drivers/cpufreq/cpufreq.c | 58 |
1 files changed, 35 insertions, 23 deletions
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index fa988bd1e606..194a6587a1de 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -616,6 +616,24 @@ static struct cpufreq_governor *find_governor(const char *str_governor) return NULL; } +static struct cpufreq_governor *get_governor(const char *str_governor) +{ + struct cpufreq_governor *t; + + mutex_lock(&cpufreq_governor_mutex); + t = find_governor(str_governor); + if (!t) + goto unlock; + + if (!try_module_get(t->owner)) + t = NULL; + +unlock: + mutex_unlock(&cpufreq_governor_mutex); + + return t; +} + static unsigned int cpufreq_parse_policy(char *str_governor) { if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) @@ -635,28 +653,14 @@ static struct cpufreq_governor *cpufreq_parse_governor(char *str_governor) { struct cpufreq_governor *t; - mutex_lock(&cpufreq_governor_mutex); + t = get_governor(str_governor); + if (t) + return t; - t = find_governor(str_governor); - if (!t) { - int ret; - - mutex_unlock(&cpufreq_governor_mutex); - - ret = request_module("cpufreq_%s", str_governor); - if (ret) - return NULL; - - 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 (request_module("cpufreq_%s", str_governor)) + return NULL; - return t; + return get_governor(str_governor); } /** @@ -810,12 +814,14 @@ static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, goto out; } + mutex_lock(&cpufreq_governor_mutex); for_each_governor(t) { if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) - (CPUFREQ_NAME_LEN + 2))) - goto out; + break; i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); } + mutex_unlock(&cpufreq_governor_mutex); out: i += sprintf(&buf[i], "\n"); return i; @@ -1053,15 +1059,17 @@ static int cpufreq_init_policy(struct cpufreq_policy *policy) struct cpufreq_governor *def_gov = cpufreq_default_governor(); struct cpufreq_governor *gov = NULL; unsigned int pol = CPUFREQ_POLICY_UNKNOWN; + int ret; if (has_target()) { /* Update policy governor to the one used before hotplug. */ - gov = find_governor(policy->last_governor); + gov = get_governor(policy->last_governor); if (gov) { pr_debug("Restoring governor %s for cpu %d\n", policy->governor->name, policy->cpu); } else if (def_gov) { gov = def_gov; + __module_get(gov->owner); } else { return -ENODATA; } @@ -1084,7 +1092,11 @@ static int cpufreq_init_policy(struct cpufreq_policy *policy) return -ENODATA; } - return cpufreq_set_policy(policy, gov, pol); + ret = cpufreq_set_policy(policy, gov, pol); + if (gov) + module_put(gov->owner); + + return ret; } static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) |