ARM, sched/topology: Revert back to default scheduler topology (d23b3bf8) · Commits · 戴 / test

The ARM-specific GMC level is meant to be built using the thread sibling mask, but no devicetree in arch/arm/boot/dts uses the 'thread' cpu-map binding. With SD_SHARE_POWERDOMAIN gone, this topology level can be removed, at which point ARM no longer benefits from having a custom defined topology table. Delete the GMC topology level by making ARM use the default scheduler topology table. This essentially reverts commit: ("sched, ARM: Create a dedicated scheduler topology table") No change in functionality is expected. Suggested-by:

Dietmar Eggemann <dietmar.eggemann@arm.com> Signed-off-by:

Valentin Schneider <valentin.schneider@arm.com> Signed-off-by:

Ingo Molnar <mingo@kernel.org> Reviewed-by:

Dietmar Eggemann <dietmar.eggemann@arm.com> Acked-by:

Peter Zijlstra <a.p.zijlstra@chello.nl> Link: https://lore.kernel.org/r/20200817113003.20802-3-valentin.schneider@arm.com

arch/arm/kernel/topology.c

+0 −26

Original line number	Diff line number	Diff line
		@@ -177,15 +177,6 @@ static inline void parse_dt_topology(void) {}
		static inline void update_cpu_capacity(unsigned int cpuid) {}
		#endif

		/*
		* The current assumption is that we can power gate each core independently.
		* This will be superseded by DT binding once available.
		*/
		const struct cpumask *cpu_corepower_mask(int cpu)
		{
		return &cpu_topology[cpu].thread_sibling;
		}

		/*
		* store_cpu_topology is called at boot when only one cpu is running
		* and with the mutex cpu_hotplug.lock locked, when several cpus have booted,
		@@ -241,20 +232,6 @@ topology_populated:
		update_siblings_masks(cpuid);
		}

		static inline int cpu_corepower_flags(void)
		{
		return SD_SHARE_PKG_RESOURCES;
		}

		static struct sched_domain_topology_level arm_topology[] = {
		#ifdef CONFIG_SCHED_MC
		{ cpu_corepower_mask, cpu_corepower_flags, SD_INIT_NAME(GMC) },
		{ cpu_coregroup_mask, cpu_core_flags, SD_INIT_NAME(MC) },
		#endif
		{ cpu_cpu_mask, SD_INIT_NAME(DIE) },
		{ NULL, },
		};

		/*
		* init_cpu_topology is called at boot when only one cpu is running
		* which prevent simultaneous write access to cpu_topology array
		@@ -265,7 +242,4 @@ void __init init_cpu_topology(void)
		smp_wmb();

		parse_dt_topology();

		/* Set scheduler topology descriptor */
		set_sched_topology(arm_topology);
		}

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