[PATCH v1] PM: EM: Move sched domains rebuild function from schedutil to EM
From: Rafael J. Wysocki
Date: Thu Dec 12 2024 - 07:05:04 EST
From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Function sugov_eas_rebuild_sd() defined in the schedutil cpufreq governor
implements generic functionality that may be useful in other places. In
particular, there is a plan to use it in the intel_pstate driver in the
future.
For this reason, move it from schedutil to the energy model code and
rename it to em_rebuild_sched_domains().
This also helps to get rid of some #ifdeffery in schedutil which is a
plus.
No intentional functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
The previous RFC version of this patch is here:
https://lore.kernel.org/linux-pm/2229205.irdbgypaU6@xxxxxxxxxxxxx/
Changes since the RFC:
* The new function is called em_rebuild_sched_domains() now.
* Update the subject and changelog.
* Reword the comment in sugov_policy_alloc().
---
drivers/cpufreq/cpufreq.c | 2 +-
include/linux/energy_model.h | 2 ++
kernel/power/energy_model.c | 17 +++++++++++++++++
kernel/sched/cpufreq_schedutil.c | 33 ++++++---------------------------
4 files changed, 26 insertions(+), 28 deletions(-)
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1538,7 +1538,7 @@
/*
* Register with the energy model before
- * sugov_eas_rebuild_sd() is called, which will result
+ * em_rebuild_sched_domains() is called, which will result
* in rebuilding of the sched domains, which should only be done
* once the energy model is properly initialized for the policy
* first.
--- a/include/linux/energy_model.h
+++ b/include/linux/energy_model.h
@@ -179,6 +179,7 @@
int em_dev_update_chip_binning(struct device *dev);
int em_update_performance_limits(struct em_perf_domain *pd,
unsigned long freq_min_khz, unsigned long freq_max_khz);
+void em_rebuild_sched_domains(void);
/**
* em_pd_get_efficient_state() - Get an efficient performance state from the EM
@@ -404,6 +405,7 @@
{
return -EINVAL;
}
+static inline void em_rebuild_sched_domains(void) {}
#endif
#endif
--- a/kernel/power/energy_model.c
+++ b/kernel/power/energy_model.c
@@ -908,3 +908,20 @@
return 0;
}
EXPORT_SYMBOL_GPL(em_update_performance_limits);
+
+static void rebuild_sd_workfn(struct work_struct *work)
+{
+ rebuild_sched_domains_energy();
+}
+
+void em_rebuild_sched_domains(void)
+{
+ static DECLARE_WORK(rebuild_sd_work, rebuild_sd_workfn);
+
+ /*
+ * When called from the cpufreq_register_driver() path, the
+ * cpu_hotplug_lock is already held, so use a work item to
+ * avoid nested locking in rebuild_sched_domains().
+ */
+ schedule_work(&rebuild_sd_work);
+}
--- a/kernel/sched/cpufreq_schedutil.c
+++ b/kernel/sched/cpufreq_schedutil.c
@@ -604,31 +604,6 @@
/********************** cpufreq governor interface *********************/
-#ifdef CONFIG_ENERGY_MODEL
-static void rebuild_sd_workfn(struct work_struct *work)
-{
- rebuild_sched_domains_energy();
-}
-
-static DECLARE_WORK(rebuild_sd_work, rebuild_sd_workfn);
-
-/*
- * EAS shouldn't be attempted without sugov, so rebuild the sched_domains
- * on governor changes to make sure the scheduler knows about it.
- */
-static void sugov_eas_rebuild_sd(void)
-{
- /*
- * When called from the cpufreq_register_driver() path, the
- * cpu_hotplug_lock is already held, so use a work item to
- * avoid nested locking in rebuild_sched_domains().
- */
- schedule_work(&rebuild_sd_work);
-}
-#else
-static inline void sugov_eas_rebuild_sd(void) { };
-#endif
-
struct cpufreq_governor schedutil_gov;
static struct sugov_policy *sugov_policy_alloc(struct cpufreq_policy *policy)
@@ -784,7 +759,11 @@
goto fail;
out:
- sugov_eas_rebuild_sd();
+ /*
+ * Schedutil is the preferred governor for EAS, so rebuild sched domains
+ * on governor changes to make sure the scheduler knows about them.
+ */
+ em_rebuild_sched_domains();
mutex_unlock(&global_tunables_lock);
return 0;
@@ -826,7 +805,7 @@
sugov_policy_free(sg_policy);
cpufreq_disable_fast_switch(policy);
- sugov_eas_rebuild_sd();
+ em_rebuild_sched_domains();
}
static int sugov_start(struct cpufreq_policy *policy)