From 25980c7a79af42f2daa73e2f475ebf4cbac8253e Mon Sep 17 00:00:00 2001 From: Valentin Schneider Date: Sun, 12 Jul 2020 17:59:15 +0100 Subject: [PATCH] arch_topology, sched/core: Cleanup thermal pressure definition The following commit: 14533a16c46d ("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 Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20200712165917.9168-2-valentin.schneider@arm.com --- arch/arm/include/asm/topology.h | 3 ++- arch/arm64/include/asm/topology.h | 3 ++- drivers/base/arch_topology.c | 11 +++++++++++ include/linux/arch_topology.h | 4 ++-- include/linux/sched/topology.h | 7 +++++++ kernel/sched/core.c | 11 ----------- 6 files changed, 24 insertions(+), 15 deletions(-) diff --git a/arch/arm/include/asm/topology.h b/arch/arm/include/asm/topology.h index 435aba2..e0593cf 100644 --- a/arch/arm/include/asm/topology.h +++ b/arch/arm/include/asm/topology.h @@ -16,8 +16,9 @@ /* Enable topology flag updates */ #define arch_update_cpu_topology topology_update_cpu_topology -/* Replace task scheduler's default thermal pressure retrieve API */ +/* Replace task scheduler's default thermal pressure API */ #define arch_scale_thermal_pressure topology_get_thermal_pressure +#define arch_set_thermal_pressure topology_set_thermal_pressure #else diff --git a/arch/arm64/include/asm/topology.h b/arch/arm64/include/asm/topology.h index 0cc835d..e042f65 100644 --- a/arch/arm64/include/asm/topology.h +++ b/arch/arm64/include/asm/topology.h @@ -34,8 +34,9 @@ void topology_scale_freq_tick(void); /* Enable topology flag updates */ #define arch_update_cpu_topology topology_update_cpu_topology -/* Replace task scheduler's default thermal pressure retrieve API */ +/* Replace task scheduler's default thermal pressure API */ #define arch_scale_thermal_pressure topology_get_thermal_pressure +#define arch_set_thermal_pressure topology_set_thermal_pressure #include diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c index 4d0a003..75f72d6 100644 --- a/drivers/base/arch_topology.c +++ b/drivers/base/arch_topology.c @@ -54,6 +54,17 @@ void topology_set_cpu_scale(unsigned int cpu, unsigned long capacity) per_cpu(cpu_scale, cpu) = capacity; } +DEFINE_PER_CPU(unsigned long, thermal_pressure); + +void topology_set_thermal_pressure(const struct cpumask *cpus, + unsigned long th_pressure) +{ + int cpu; + + for_each_cpu(cpu, cpus) + WRITE_ONCE(per_cpu(thermal_pressure, cpu), th_pressure); +} + static ssize_t cpu_capacity_show(struct device *dev, struct device_attribute *attr, char *buf) diff --git a/include/linux/arch_topology.h b/include/linux/arch_topology.h index 0566cb3..69b1dab 100644 --- a/include/linux/arch_topology.h +++ b/include/linux/arch_topology.h @@ -39,8 +39,8 @@ static inline unsigned long topology_get_thermal_pressure(int cpu) return per_cpu(thermal_pressure, cpu); } -void arch_set_thermal_pressure(struct cpumask *cpus, - unsigned long th_pressure); +void topology_set_thermal_pressure(const struct cpumask *cpus, + unsigned long th_pressure); struct cpu_topology { int thread_id; diff --git a/include/linux/sched/topology.h b/include/linux/sched/topology.h index fb11091..764222d 100644 --- a/include/linux/sched/topology.h +++ b/include/linux/sched/topology.h @@ -232,6 +232,13 @@ unsigned long arch_scale_thermal_pressure(int cpu) } #endif +#ifndef arch_set_thermal_pressure +static __always_inline +void arch_set_thermal_pressure(const struct cpumask *cpus, + unsigned long th_pressure) +{ } +#endif + static inline int task_node(const struct task_struct *p) { return cpu_to_node(task_cpu(p)); diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 12db8fb..bd8e521 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -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. -- 2.7.4