arch_topology, sched/core: Cleanup thermal pressure definition

The following commit:

  14533a16c4 ("thermal/cpu-cooling, sched/core: Move the arch_set_thermal_pressure() API to generic scheduler code")

moved the definition of arch_set_thermal_pressure() to sched/core.c, but
kept its declaration in linux/arch_topology.h. When building e.g. an x86
kernel with CONFIG_SCHED_THERMAL_PRESSURE=y, cpufreq_cooling.c ends up
getting the declaration of arch_set_thermal_pressure() from
include/linux/arch_topology.h, which is somewhat awkward.

On top of this, sched/core.c unconditionally defines
o The thermal_pressure percpu variable
o arch_set_thermal_pressure()

while arch_scale_thermal_pressure() does nothing unless redefined by the
architecture.

arch_*() functions are meant to be defined by architectures, so revert the
aforementioned commit and re-implement it in a way that keeps
arch_set_thermal_pressure() architecture-definable, and doesn't define the
thermal pressure percpu variable for kernels that don't need
it (CONFIG_SCHED_THERMAL_PRESSURE=n).

Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200712165917.9168-2-valentin.schneider@arm.com
This commit is contained in:
Valentin Schneider
2020-07-12 17:59:15 +01:00
committed by Peter Zijlstra
parent 2705937a03
commit 25980c7a79
6 changed files with 24 additions and 15 deletions

View File

@@ -3869,17 +3869,6 @@ unsigned long long task_sched_runtime(struct task_struct *p)
return ns;
}
DEFINE_PER_CPU(unsigned long, thermal_pressure);
void arch_set_thermal_pressure(struct cpumask *cpus,
unsigned long th_pressure)
{
int cpu;
for_each_cpu(cpu, cpus)
WRITE_ONCE(per_cpu(thermal_pressure, cpu), th_pressure);
}
/*
* This function gets called by the timer code, with HZ frequency.
* We call it with interrupts disabled.