Commit 19a469a5 authored by Marc Zyngier's avatar Marc Zyngier Committed by Catalin Marinas
Browse files

drivers/perf: arm-pmu: Handle per-interrupt affinity mask 



On a big-little system, PMUs can be wired to CPUs using per CPU
interrups (PPI). In this case, it is important to make sure that
the enable/disable do happen on the right set of CPUs.

So instead of relying on the interrupt-affinity property, we can
use the actual percpu affinity that DT exposes as part of the
interrupt specifier. The DT binding is also updated to reflect
the fact that the interrupt-affinity property shouldn't be used
in that case.

Acked-by: default avatarRob Herring <robh@kernel.org>
Tested-by: default avatarCaesar Wang <wxt@rock-chips.com>
Signed-off-by: default avatarMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent 90f777be

Documentation/devicetree/bindings/arm/pmu.txt

+3 −1
Original line number Diff line number Diff line
@@ -39,7 +39,9 @@ Optional properties: 
                       When using a PPI, specifies a list of phandles to CPU

		       nodes corresponding to the set of CPUs which have

		       a PMU of this type signalling the PPI listed in the

		       interrupts property.

		       interrupts property, unless this is already specified

		       by the PPI interrupt specifier itself (in which case

		       the interrupt-affinity property shouldn't be present).



                       This property should be present when there is more than

		       a single SPI.

drivers/perf/arm_pmu.c

+22 −5
Original line number Diff line number Diff line
@@ -603,7 +603,8 @@ static void cpu_pmu_free_irq(struct arm_pmu *cpu_pmu) 


	irq = platform_get_irq(pmu_device, 0);

	if (irq >= 0 && irq_is_percpu(irq)) {

		on_each_cpu(cpu_pmu_disable_percpu_irq, &irq, 1);

		on_each_cpu_mask(&cpu_pmu->supported_cpus,

				 cpu_pmu_disable_percpu_irq, &irq, 1);

		free_percpu_irq(irq, &hw_events->percpu_pmu);

	} else {

		for (i = 0; i < irqs; ++i) {
@@ -645,7 +646,9 @@ static int cpu_pmu_request_irq(struct arm_pmu *cpu_pmu, irq_handler_t handler) 
				irq);

			return err;

		}

		on_each_cpu(cpu_pmu_enable_percpu_irq, &irq, 1);



		on_each_cpu_mask(&cpu_pmu->supported_cpus,

				 cpu_pmu_enable_percpu_irq, &irq, 1);

	} else {

		for (i = 0; i < irqs; ++i) {

			int cpu = i;
@@ -961,9 +964,23 @@ static int of_pmu_irq_cfg(struct arm_pmu *pmu) 
		i++;

	} while (1);



	/* If we didn't manage to parse anything, claim to support all CPUs */

	if (cpumask_weight(&pmu->supported_cpus) == 0)

	/* If we didn't manage to parse anything, try the interrupt affinity */

	if (cpumask_weight(&pmu->supported_cpus) == 0) {

		if (!using_spi) {

			/* If using PPIs, check the affinity of the partition */

			int ret, irq;



			irq = platform_get_irq(pdev, 0);

			ret = irq_get_percpu_devid_partition(irq, &pmu->supported_cpus);

			if (ret) {

				kfree(irqs);

				return ret;

			}

		} else {

			/* Otherwise default to all CPUs */

			cpumask_setall(&pmu->supported_cpus);

		}

	}



	/* If we matched up the IRQ affinities, use them to route the SPIs */

	if (using_spi && i == pdev->num_resources)

CRA Git | Maintained and supported by SUSTech CRA and CCSE