From 9942cb22ea458c34fa17b73d143ea32d4df1caca Mon Sep 17 00:00:00 2001 From: Vincent Guittot Date: Mon, 11 Dec 2023 11:48:49 +0100 Subject: sched/topology: Add a new arch_scale_freq_ref() method Create a new method to get a unique and fixed max frequency. Currently cpuinfo.max_freq or the highest (or last) state of performance domain are used as the max frequency when computing the frequency for a level of utilization, but: - cpuinfo_max_freq can change at runtime. boost is one example of such change. - cpuinfo.max_freq and last item of the PD can be different leading to different results between cpufreq and energy model. We need to save the reference frequency that has been used when computing the CPUs capacity and use this fixed and coherent value to convert between frequency and CPU's capacity. In fact, we already save the frequency that has been used when computing the capacity of each CPU. We extend the precision to save kHz instead of MHz currently and we modify the type to be aligned with other variables used when converting frequency to capacity and the other way. [ mingo: Minor edits. ] Signed-off-by: Vincent Guittot Signed-off-by: Ingo Molnar Tested-by: Lukasz Luba Reviewed-by: Lukasz Luba Acked-by: Sudeep Holla Link: https://lore.kernel.org/r/20231211104855.558096-2-vincent.guittot@linaro.org --- arch/arm/include/asm/topology.h | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/arm') diff --git a/arch/arm/include/asm/topology.h b/arch/arm/include/asm/topology.h index c7d2510e5a78..853c4f81ba4a 100644 --- a/arch/arm/include/asm/topology.h +++ b/arch/arm/include/asm/topology.h @@ -13,6 +13,7 @@ #define arch_set_freq_scale topology_set_freq_scale #define arch_scale_freq_capacity topology_get_freq_scale #define arch_scale_freq_invariant topology_scale_freq_invariant +#define arch_scale_freq_ref topology_get_freq_ref #endif /* Replace task scheduler's default cpu-invariant accounting */ -- cgit v1.2.3