[PATCH 08/16] cpufreq: intel_pstate: Drop driver_registered variable
From: Rafael J. Wysocki
Date: Mon Mar 27 2017 - 18:44:56 EST
From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
The driver_registered variable in intel_pstate is used for checking
whether or not the driver has been registered, but intel_pstate_driver
can be used for that too (with the rule that the driver is not
registered as long as it is NULL).
That is a bit more straightforward and the code may be simplified
a bit this way, so modify the driver accordingly.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
drivers/cpufreq/intel_pstate.c | 46 ++++++++++++++++-------------------------
1 file changed, 19 insertions(+), 27 deletions(-)
Index: linux-pm/drivers/cpufreq/intel_pstate.c
===================================================================
--- linux-pm.orig/drivers/cpufreq/intel_pstate.c
+++ linux-pm/drivers/cpufreq/intel_pstate.c
@@ -349,7 +349,7 @@ static struct pstate_adjust_policy pid_p
static int hwp_active __read_mostly;
static bool per_cpu_limits __read_mostly;
-static bool driver_registered __read_mostly;
+static struct cpufreq_driver *intel_pstate_driver __read_mostly;
#ifdef CONFIG_ACPI
static bool acpi_ppc;
@@ -1035,7 +1035,7 @@ static ssize_t show_turbo_pct(struct kob
mutex_lock(&intel_pstate_driver_lock);
- if (!driver_registered) {
+ if (!intel_pstate_driver) {
mutex_unlock(&intel_pstate_driver_lock);
return -EAGAIN;
}
@@ -1060,7 +1060,7 @@ static ssize_t show_num_pstates(struct k
mutex_lock(&intel_pstate_driver_lock);
- if (!driver_registered) {
+ if (!intel_pstate_driver) {
mutex_unlock(&intel_pstate_driver_lock);
return -EAGAIN;
}
@@ -1080,7 +1080,7 @@ static ssize_t show_no_turbo(struct kobj
mutex_lock(&intel_pstate_driver_lock);
- if (!driver_registered) {
+ if (!intel_pstate_driver) {
mutex_unlock(&intel_pstate_driver_lock);
return -EAGAIN;
}
@@ -1108,7 +1108,7 @@ static ssize_t store_no_turbo(struct kob
mutex_lock(&intel_pstate_driver_lock);
- if (!driver_registered) {
+ if (!intel_pstate_driver) {
mutex_unlock(&intel_pstate_driver_lock);
return -EAGAIN;
}
@@ -1155,7 +1155,7 @@ static ssize_t store_max_perf_pct(struct
mutex_lock(&intel_pstate_driver_lock);
- if (!driver_registered) {
+ if (!intel_pstate_driver) {
mutex_unlock(&intel_pstate_driver_lock);
return -EAGAIN;
}
@@ -1185,7 +1185,7 @@ static ssize_t store_min_perf_pct(struct
mutex_lock(&intel_pstate_driver_lock);
- if (!driver_registered) {
+ if (!intel_pstate_driver) {
mutex_unlock(&intel_pstate_driver_lock);
return -EAGAIN;
}
@@ -2255,7 +2255,7 @@ static struct cpufreq_driver intel_cpufr
.name = "intel_cpufreq",
};
-static struct cpufreq_driver *intel_pstate_driver = &intel_pstate;
+static struct cpufreq_driver *default_driver = &intel_pstate;
static void intel_pstate_driver_cleanup(void)
{
@@ -2272,15 +2272,17 @@ static void intel_pstate_driver_cleanup(
}
}
put_online_cpus();
+ intel_pstate_driver = NULL;
}
-static int intel_pstate_register_driver(void)
+static int intel_pstate_register_driver(struct cpufreq_driver *driver)
{
int ret;
memset(&global, 0, sizeof(global));
global.max_perf_pct = 100;
+ intel_pstate_driver = driver;
ret = cpufreq_register_driver(intel_pstate_driver);
if (ret) {
intel_pstate_driver_cleanup();
@@ -2289,10 +2291,6 @@ static int intel_pstate_register_driver(
global.min_perf_pct = min_perf_pct_min();
- mutex_lock(&intel_pstate_limits_lock);
- driver_registered = true;
- mutex_unlock(&intel_pstate_limits_lock);
-
if (intel_pstate_driver == &intel_pstate && !hwp_active &&
pstate_funcs.get_target_pstate != get_target_pstate_use_cpu_load)
intel_pstate_debug_expose_params();
@@ -2309,10 +2307,6 @@ static int intel_pstate_unregister_drive
pstate_funcs.get_target_pstate != get_target_pstate_use_cpu_load)
intel_pstate_debug_hide_params();
- mutex_lock(&intel_pstate_limits_lock);
- driver_registered = false;
- mutex_unlock(&intel_pstate_limits_lock);
-
cpufreq_unregister_driver(intel_pstate_driver);
intel_pstate_driver_cleanup();
@@ -2321,7 +2315,7 @@ static int intel_pstate_unregister_drive
static ssize_t intel_pstate_show_status(char *buf)
{
- if (!driver_registered)
+ if (!intel_pstate_driver)
return sprintf(buf, "off\n");
return sprintf(buf, "%s\n", intel_pstate_driver == &intel_pstate ?
@@ -2333,11 +2327,11 @@ static int intel_pstate_update_status(co
int ret;
if (size == 3 && !strncmp(buf, "off", size))
- return driver_registered ?
+ return intel_pstate_driver ?
intel_pstate_unregister_driver() : -EINVAL;
if (size == 6 && !strncmp(buf, "active", size)) {
- if (driver_registered) {
+ if (intel_pstate_driver) {
if (intel_pstate_driver == &intel_pstate)
return 0;
@@ -2346,12 +2340,11 @@ static int intel_pstate_update_status(co
return ret;
}
- intel_pstate_driver = &intel_pstate;
- return intel_pstate_register_driver();
+ return intel_pstate_register_driver(&intel_pstate);
}
if (size == 7 && !strncmp(buf, "passive", size)) {
- if (driver_registered) {
+ if (intel_pstate_driver) {
if (intel_pstate_driver != &intel_pstate)
return 0;
@@ -2360,8 +2353,7 @@ static int intel_pstate_update_status(co
return ret;
}
- intel_pstate_driver = &intel_cpufreq;
- return intel_pstate_register_driver();
+ return intel_pstate_register_driver(&intel_cpufreq);
}
return -EINVAL;
@@ -2601,7 +2593,7 @@ hwp_cpu_matched:
intel_pstate_sysfs_expose_params();
mutex_lock(&intel_pstate_driver_lock);
- rc = intel_pstate_register_driver();
+ rc = intel_pstate_register_driver(default_driver);
mutex_unlock(&intel_pstate_driver_lock);
if (rc)
return rc;
@@ -2622,7 +2614,7 @@ static int __init intel_pstate_setup(cha
no_load = 1;
} else if (!strcmp(str, "passive")) {
pr_info("Passive mode enabled\n");
- intel_pstate_driver = &intel_cpufreq;
+ default_driver = &intel_cpufreq;
no_hwp = 1;
}
if (!strcmp(str, "no_hwp")) {