From ef7e7d65eb808b5d37b4596974526962a741e930 Mon Sep 17 00:00:00 2001 From: Hanjun Guo Date: Tue, 19 May 2020 14:25:21 +0800 Subject: [PATCH] cpuidle: sysfs: Accept governor name with 15 characters CPUIDLE_NAME_LEN is 16, so it's possible to accept governor name with 15 characters, but now store_current_governor() rejects governor name with 15 characters as it returns -EINVAL if count equals CPUIDLE_NAME_LEN. Refactor the code to accept such case and simplify the code. Signed-off-by: Hanjun Guo Reviewed-by: Doug Smythies Tested-by: Doug Smythies Signed-off-by: Rafael J. Wysocki --- drivers/cpuidle/sysfs.c | 23 +++++++---------------- 1 file changed, 7 insertions(+), 16 deletions(-) diff --git a/drivers/cpuidle/sysfs.c b/drivers/cpuidle/sysfs.c index 477b05afaf81..a57ad10baccc 100644 --- a/drivers/cpuidle/sysfs.c +++ b/drivers/cpuidle/sysfs.c @@ -85,34 +85,25 @@ static ssize_t store_current_governor(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { - char gov_name[CPUIDLE_NAME_LEN]; - int ret = -EINVAL; - size_t len = count; + char gov_name[CPUIDLE_NAME_LEN + 1]; + int ret; struct cpuidle_governor *gov; - if (!len || len >= sizeof(gov_name)) + ret = sscanf(buf, "%" __stringify(CPUIDLE_NAME_LEN) "s", gov_name); + if (ret != 1) return -EINVAL; - memcpy(gov_name, buf, len); - gov_name[len] = '\0'; - if (gov_name[len - 1] == '\n') - gov_name[--len] = '\0'; - mutex_lock(&cpuidle_lock); - + ret = -EINVAL; list_for_each_entry(gov, &cpuidle_governors, governor_list) { - if (strlen(gov->name) == len && !strcmp(gov->name, gov_name)) { + if (!strncmp(gov->name, gov_name, CPUIDLE_NAME_LEN)) { ret = cpuidle_switch_governor(gov); break; } } - mutex_unlock(&cpuidle_lock); - if (ret) - return ret; - else - return count; + return ret ? ret : count; } static DEVICE_ATTR(current_driver, 0444, show_current_driver, NULL);