Commit 47b10b73 authored by Viresh Kumar's avatar Viresh Kumar Committed by Will Deacon
Browse files

arm64: topology: Reorder init_amu_fie() a bit 



This patch does a couple of optimizations in init_amu_fie(), like early
exits from paths where we don't need to continue any further, avoid the
enable/disable dance, moving the calls to
topology_scale_freq_invariant() just when we need them, instead of at
the top of the routine, and avoiding calling it for the third time.

Reviewed-by: default avatarIonela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: default avatarViresh Kumar <viresh.kumar@linaro.org>
Tested-by: default avatarIonela Voinescu <ionela.voinescu@arm.com>
Link: https://lore.kernel.org/r/a732e71ab9ec28c354eb28dd898c9b47d490863f.1610104461.git.viresh.kumar@linaro.org


Signed-off-by: default avatarWill Deacon <will@kernel.org>
parent 384e5699

arch/arm64/kernel/topology.c

+14 −13
Original line number Diff line number Diff line
@@ -221,8 +221,8 @@ static DEFINE_STATIC_KEY_FALSE(amu_fie_key); 


static int __init init_amu_fie(void)

{

	bool invariance_status = topology_scale_freq_invariant();

	cpumask_var_t valid_cpus;

	bool invariant;

	int ret = 0;

	int cpu;
@@ -249,18 +249,19 @@ static int __init init_amu_fie(void) 
	if (cpumask_equal(valid_cpus, cpu_present_mask))

		cpumask_copy(amu_fie_cpus, cpu_present_mask);



	if (!cpumask_empty(amu_fie_cpus)) {

		pr_info("CPUs[%*pbl]: counters will be used for FIE.",

			cpumask_pr_args(amu_fie_cpus));

	if (cpumask_empty(amu_fie_cpus))

		goto free_valid_mask;



	invariant = topology_scale_freq_invariant();



	/* We aren't fully invariant yet */

	if (!invariant && !cpumask_equal(amu_fie_cpus, cpu_present_mask))

		goto free_valid_mask;



	static_branch_enable(&amu_fie_key);

	}



	/*

	 * If the system is not fully invariant after AMU init, disable

	 * partial use of counters for frequency invariance.

	 */

	if (!topology_scale_freq_invariant())

		static_branch_disable(&amu_fie_key);

	pr_info("CPUs[%*pbl]: counters will be used for FIE.",

		cpumask_pr_args(amu_fie_cpus));



	/*

	 * Task scheduler behavior depends on frequency invariance support,
@@ -268,7 +269,7 @@ static int __init init_amu_fie(void) 
	 * a result of counter initialisation and use, retrigger the build of

	 * scheduling domains to ensure the information is propagated properly.

	 */

	if (invariance_status != topology_scale_freq_invariant())

	if (!invariant)

		rebuild_sched_domains_energy();



free_valid_mask: