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ARM: perf: extend interrupt-affinity property for PPIs

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On systems containing multiple, heterogeneous clusters we need a way to
associate a PMU "device" with the CPU(s) on which it exists. For PMUs
that signal overflow with SPIs, this relationship is determined via the
"interrupt-affinity" property, which contains a list of phandles to CPU
nodes for the PMU. For PMUs using PPIs, the per-cpu nature of the
interrupt isn't enough to determine the set of CPUs which actually
contain the device.

This patch allows the interrupt-affinity property to be specified on a
PMU node irrespective of the interrupt type. For PPIs, it identifies
the set of CPUs signalling the PPI in question.

Tested-by: Stephen Boyd <sboyd@codeaurora.org> # Krait PMU
Signed-off-by: Will Deacon <will.deacon@arm.com>
This commit is contained in:
Will Deacon 2015-06-29 13:59:01 +01:00
parent 8ae81c25cf
commit b6c084d7aa
2 changed files with 55 additions and 26 deletions
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12
Documentation/devicetree/bindings/arm/pmu.txt
View File

@ -26,13 +26,19 @@ Required properties:
Optional properties: Optional properties:
- interrupt-affinity : Valid only when using SPIs, specifies a list of phandles - interrupt-affinity : When using SPIs, specifies a list of phandles to CPU
to CPU nodes corresponding directly to the affinity of nodes corresponding directly to the affinity of
the SPIs listed in the interrupts property. the SPIs listed in the interrupts property.
This property should be present when there is more than 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.
This property should be present when there is more than
a single SPI. a single SPI.
- qcom,no-pc-write : Indicates that this PMU doesn't support the 0xc and 0xd - qcom,no-pc-write : Indicates that this PMU doesn't support the 0xc and 0xd
events. events.

69
arch/arm/kernel/perf_event.c
View File

@ -790,32 +790,39 @@ static int probe_current_pmu(struct arm_pmu *pmu,
static int of_pmu_irq_cfg(struct arm_pmu *pmu) static int of_pmu_irq_cfg(struct arm_pmu *pmu)
{ {
int i, irq, *irqs; int *irqs, i = 0;
bool using_spi = false;
struct platform_device *pdev = pmu->plat_device; struct platform_device *pdev = pmu->plat_device;
/* Don't bother with PPIs; they're already affine */
irq = platform_get_irq(pdev, 0);
if (irq >= 0 && irq_is_percpu(irq)) {
cpumask_setall(&pmu->supported_cpus);
return 0;
}
irqs = kcalloc(pdev->num_resources, sizeof(*irqs), GFP_KERNEL); irqs = kcalloc(pdev->num_resources, sizeof(*irqs), GFP_KERNEL);
if (!irqs) if (!irqs)
return -ENOMEM; return -ENOMEM;
for (i = 0; i < pdev->num_resources; ++i) { do {
struct device_node *dn; struct device_node *dn;
int cpu; int cpu, irq;
dn = of_parse_phandle(pdev->dev.of_node, "interrupt-affinity", /* See if we have an affinity entry */
i); dn = of_parse_phandle(pdev->dev.of_node, "interrupt-affinity", i);
if (!dn) { if (!dn)
pr_warn("Failed to parse %s/interrupt-affinity[%d]\n",
of_node_full_name(pdev->dev.of_node), i);
break; break;
/* Check the IRQ type and prohibit a mix of PPIs and SPIs */
irq = platform_get_irq(pdev, i);
if (irq >= 0) {
bool spi = !irq_is_percpu(irq);
if (i > 0 && spi != using_spi) {
pr_err("PPI/SPI IRQ type mismatch for %s!\n",
dn->name);
kfree(irqs);
return -EINVAL;
}
using_spi = spi;
} }
/* Now look up the logical CPU number */
for_each_possible_cpu(cpu) for_each_possible_cpu(cpu)
if (arch_find_n_match_cpu_physical_id(dn, cpu, NULL)) if (arch_find_n_match_cpu_physical_id(dn, cpu, NULL))
break; break;
@ -824,20 +831,36 @@ static int of_pmu_irq_cfg(struct arm_pmu *pmu)
pr_warn("Failed to find logical CPU for %s\n", pr_warn("Failed to find logical CPU for %s\n",
dn->name); dn->name);
of_node_put(dn); of_node_put(dn);
cpumask_setall(&pmu->supported_cpus);
break; break;
} }
of_node_put(dn); of_node_put(dn);
irqs[i] = cpu; /* For SPIs, we need to track the affinity per IRQ */
cpumask_set_cpu(cpu, &pmu->supported_cpus); if (using_spi) {
} if (i >= pdev->num_resources) {
of_node_put(dn);
break;
}
if (i == pdev->num_resources) { irqs[i] = cpu;
pmu->irq_affinity = irqs; }
} else {
kfree(irqs); /* Keep track of the CPUs containing this PMU type */
cpumask_set_cpu(cpu, &pmu->supported_cpus);
of_node_put(dn);
i++;
} while (1);
/* If we didn't manage to parse anything, claim to support all CPUs */
if (cpumask_weight(&pmu->supported_cpus) == 0)
cpumask_setall(&pmu->supported_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)
pmu->irq_affinity = irqs;
else
kfree(irqs);
return 0; return 0;
} }