Commit 827db839 authored by Thomas Gleixner's avatar Thomas Gleixner Committed by Ingo Molnar
Browse files

perf/x86/intel/cqm: Get rid of the silly for_each_cpu() lookups 



CQM is a strict per package facility. Use the proper cpumasks to lookup the
readers.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Harish Chegondi <harish.chegondi@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/20160222221012.054916179@linutronix.de


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 3712bba1

arch/x86/events/intel/cqm.c

+11 −21
Original line number Original line Diff line number Diff line
@@ -1244,14 +1244,11 @@ static struct pmu intel_cqm_pmu = { 




static inline void cqm_pick_event_reader(int cpu)

static inline void cqm_pick_event_reader(int cpu)

{

{

	int phys_id = topology_physical_package_id(cpu);

	int reader;

	int i;



	for_each_cpu(i, &cqm_cpumask) {

		if (phys_id == topology_physical_package_id(i))

			return;	/* already got reader for this socket */

	}





	/* First online cpu in package becomes the reader */

	reader = cpumask_any_and(&cqm_cpumask, topology_core_cpumask(cpu));

	if (reader >= nr_cpu_ids)

		cpumask_set_cpu(cpu, &cqm_cpumask);

		cpumask_set_cpu(cpu, &cqm_cpumask);

}

}
@@ -1270,24 +1267,17 @@ static void intel_cqm_cpu_starting(unsigned int cpu) 




static void intel_cqm_cpu_exit(unsigned int cpu)

static void intel_cqm_cpu_exit(unsigned int cpu)

{

{

	int phys_id = topology_physical_package_id(cpu);

	int target;

	int i;





	/*

	/* Is @cpu the current cqm reader for this package ? */

	 * Is @cpu a designated cqm reader?

	 */

	if (!cpumask_test_and_clear_cpu(cpu, &cqm_cpumask))

	if (!cpumask_test_and_clear_cpu(cpu, &cqm_cpumask))

		return;

		return;





	for_each_online_cpu(i) {

	/* Find another online reader in this package */

		if (i == cpu)

	target = cpumask_any_but(topology_core_cpumask(cpu), cpu);

			continue;





		if (phys_id == topology_physical_package_id(i)) {

	if (target < nr_cpu_ids)

			cpumask_set_cpu(i, &cqm_cpumask);

		cpumask_set_cpu(target, &cqm_cpumask);

			break;

		}

	}

}

}





static int intel_cqm_cpu_notifier(struct notifier_block *nb,

static int intel_cqm_cpu_notifier(struct notifier_block *nb,