81ca8262ce
Maximum Frequency Invariance has to be part of Cpu Invariance because
Frequency Invariance deals only with differences in load-tracking
introduces by Dynamic Frequency Scaling and not with limiting the
possible range of cpu frequency.
By placing Maximum Frequency Invariance into Cpu Invariance,
load-tracking is scaled via arch_scale_cpu_capacity()
in __update_load_avg() and cpu capacity is scaled via
arch_scale_cpu_capacity() in update_cpu_capacity().
To be able to save the extra multiplication in the scheduler hotpath
(__update_load_avg()) we could:
1 Inform cpufreq about base cpu capacity at boot and let it handle
scale_cpu_capacity() as well.
2 Use the cpufreq policy callback which would update a per-cpu current
cpu_scale and this value would be return in scale_cpu_capacity().
3 Use per-cpu current max_freq_scale and current cpu_scale with the
current patch.
Including <linux/cpufreq.h> in topology.h like for the arm arch doesn't
work because of CONFIG_COMPAT=y (Kernel support for 32-bit EL0).
That's why cpufreq_scale_max_freq_capacity() has to be declared extern
in topology.h.
Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
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| .. | ||
| boot | ||
| configs | ||
| crypto | ||
| include | ||
| kernel | ||
| kvm | ||
| lib | ||
| mm | ||
| net | ||
| xen | ||
| Kconfig | ||
| Kconfig.debug | ||
| Kconfig.platforms | ||
| Makefile | ||