From 01e055c120a46e78650b5f903088badbbdaae9ad Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Wed, 10 Mar 2021 08:21:04 +0530 Subject: arch_topology: Allow multiple entities to provide sched_freq_tick() callback This patch attempts to make it generic enough so other parts of the kernel can also provide their own implementation of scale_freq_tick() callback, which is called by the scheduler periodically to update the per-cpu arch_freq_scale variable. The implementations now need to provide 'struct scale_freq_data' for the CPUs for which they have hardware counters available, and a callback gets registered for each possible CPU in a per-cpu variable. The arch specific (or ARM AMU) counters are updated to adapt to this and they take the highest priority if they are available, i.e. they will be used instead of CPPC based counters for example. The special code to rebuild the sched domains, in case invariance status change for the system, is moved out of arm64 specific code and is added to arch_topology.c. Note that this also defines SCALE_FREQ_SOURCE_CPUFREQ but doesn't use it and it is added to show that cpufreq is also acts as source of information for FIE and will be used by default if no other counters are supported for a platform. Reviewed-by: Ionela Voinescu Tested-by: Ionela Voinescu Acked-by: Will Deacon # for arm64 Tested-by: Vincent Guittot Signed-off-by: Viresh Kumar --- include/linux/arch_topology.h | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/arch_topology.h b/include/linux/arch_topology.h index 583af517f123..11e555cfaecb 100644 --- a/include/linux/arch_topology.h +++ b/include/linux/arch_topology.h @@ -34,7 +34,19 @@ void topology_set_freq_scale(const struct cpumask *cpus, unsigned long cur_freq, unsigned long max_freq); bool topology_scale_freq_invariant(void); -bool arch_freq_counters_available(const struct cpumask *cpus); +enum scale_freq_source { + SCALE_FREQ_SOURCE_CPUFREQ = 0, + SCALE_FREQ_SOURCE_ARCH, +}; + +struct scale_freq_data { + enum scale_freq_source source; + void (*set_freq_scale)(void); +}; + +void topology_scale_freq_tick(void); +void topology_set_scale_freq_source(struct scale_freq_data *data, const struct cpumask *cpus); +void topology_clear_scale_freq_source(enum scale_freq_source source, const struct cpumask *cpus); DECLARE_PER_CPU(unsigned long, thermal_pressure); -- cgit v1.2.3