From 4488ba366420e083052081476e18f6476e0132ac Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 5 Dec 2018 23:45:34 +0100 Subject: [PATCH 0768/2944] cpuidle: Add cpuidle.governor= command line parameter commit 61cb5758d3c46bc1ba87694fefc0d9653613ce6b upstream 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 Signed-off-by: Yihao Wu Acked-by: Michael Wang --- 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 5017d6a..e8004a1 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -677,6 +677,9 @@ 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 6df894d..a711fac 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -702,4 +702,5 @@ 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 2965ab3..d661310 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 9fed1b82..bb93e5c 100644 --- a/drivers/cpuidle/governor.c +++ b/drivers/cpuidle/governor.c @@ -11,10 +11,13 @@ #include #include #include +#include #include #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); -- 1.8.3.1