From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> mainline inclusion from mainline-5.0 commit 61cb5758d3c46bc1ba87694fefc0d9653613ce6b category: feature bugzilla: https://bugzilla.openeuler.org/show_bug.cgi?id=34 CVE: NA Add cpuidle.governor= command line parameter to allow the default cpuidle governor to be replaced. That is useful, for example, if someone running a tickful kernel wants to use the menu governor on it. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Yubo Miao <miaoyubo@huawei.com> Signed-off-by: Xiangyou Xie <xiexiangyou@huawei.com> Reviewed-by: Hailiang Zhang <zhang.zhanghailiang@huawei.com> Reviewed-by: Hanjun Guo <guohanjun@huawei.com> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Signed-off-by: Jiajun Chen <chenjiajun8@huawei.com> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> --- Documentation/admin-guide/kernel-parameters.txt | 3 +++ drivers/cpuidle/cpuidle.c | 1 + drivers/cpuidle/cpuidle.h | 1 + drivers/cpuidle/governor.c | 9 +++++++-- 4 files changed, 12 insertions(+), 2 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 205adf7e258e3..3186256d9c0ce 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -682,6 +682,9 @@ cpuidle.off=1 [CPU_IDLE] disable the cpuidle sub-system + cpuidle.governor= + [CPU_IDLE] Name of the cpuidle governor to use. + cpufreq.off=1 [CPU_FREQ] disable the cpufreq sub-system diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index 035ce130dceda..55eb3d152521b 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -735,4 +735,5 @@ static int __init cpuidle_init(void) } module_param(off, int, 0444); +module_param_string(governor, param_governor, CPUIDLE_NAME_LEN, 0444); core_initcall(cpuidle_init); diff --git a/drivers/cpuidle/cpuidle.h b/drivers/cpuidle/cpuidle.h index 2965ab32a583f..d6613101af924 100644 --- a/drivers/cpuidle/cpuidle.h +++ b/drivers/cpuidle/cpuidle.h @@ -7,6 +7,7 @@ #define __DRIVER_CPUIDLE_H /* For internal use only */ +extern char param_governor[]; extern struct cpuidle_governor *cpuidle_curr_governor; extern struct list_head cpuidle_governors; extern struct list_head cpuidle_detected_devices; diff --git a/drivers/cpuidle/governor.c b/drivers/cpuidle/governor.c index 9fed1b8292927..bb93e5cf6a4ae 100644 --- a/drivers/cpuidle/governor.c +++ b/drivers/cpuidle/governor.c @@ -11,10 +11,13 @@ #include <linux/cpu.h> #include <linux/cpuidle.h> #include <linux/mutex.h> +#include <linux/module.h> #include <linux/pm_qos.h> #include "cpuidle.h" +char param_governor[CPUIDLE_NAME_LEN]; + LIST_HEAD(cpuidle_governors); struct cpuidle_governor *cpuidle_curr_governor; @@ -86,9 +89,11 @@ int cpuidle_register_governor(struct cpuidle_governor *gov) mutex_lock(&cpuidle_lock); if (__cpuidle_find_governor(gov->name) == NULL) { ret = 0; - list_add_tail(&gov->governor_list, &cpuidle_governors); if (!cpuidle_curr_governor || - cpuidle_curr_governor->rating < gov->rating) + !strncasecmp(param_governor, gov->name, CPUIDLE_NAME_LEN) || + (cpuidle_curr_governor->rating < gov->rating && + strncasecmp(param_governor, cpuidle_curr_governor->name, + CPUIDLE_NAME_LEN))) cpuidle_switch_governor(gov); } mutex_unlock(&cpuidle_lock); -- 2.25.1