Energy Aware Scheduling (EAS) starts when the scheduling domains are built if the Energy Model (EM) is present. However, in the typical case of Arm/Arm64 systems, the EM is provided after the scheduling domains are first built at boot time, which results in EAS staying disabled.
Fix this issue by re-building the scheduling domain from the arch topology driver, once CPUfreq is up and running and when the CPU capacities have been updated to their final value. Cc: Greg Kroah-Hartman <[email protected]> Signed-off-by: Quentin Perret <[email protected]> --- drivers/base/arch_topology.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c index e7cb0c6ade81..2022174f5ac5 100644 --- a/drivers/base/arch_topology.c +++ b/drivers/base/arch_topology.c @@ -10,7 +10,9 @@ #include <linux/arch_topology.h> #include <linux/cpu.h> #include <linux/cpufreq.h> +#include <linux/cpuset.h> #include <linux/device.h> +#include <linux/energy_model.h> #include <linux/of.h> #include <linux/slab.h> #include <linux/string.h> @@ -173,6 +175,9 @@ static cpumask_var_t cpus_to_visit; static void parsing_done_workfn(struct work_struct *work); static DECLARE_WORK(parsing_done_work, parsing_done_workfn); +static void start_eas_workfn(struct work_struct *work); +static DECLARE_WORK(start_eas_work, start_eas_workfn); + static int init_cpu_capacity_callback(struct notifier_block *nb, unsigned long val, @@ -204,6 +209,7 @@ init_cpu_capacity_callback(struct notifier_block *nb, free_raw_capacity(); pr_debug("cpu_capacity: parsing done\n"); schedule_work(&parsing_done_work); + schedule_work(&start_eas_work); } return 0; @@ -249,6 +255,15 @@ static void parsing_done_workfn(struct work_struct *work) free_cpumask_var(cpus_to_visit); } +static void start_eas_workfn(struct work_struct *work) +{ + /* Make sure the EM knows about the updated CPU capacities. */ + em_rescale_cpu_capacity(); + + /* Inform the scheduler about the EM availability. */ + rebuild_sched_domains(); +} + #else core_initcall(free_raw_capacity); #endif -- 2.17.1
