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Subject[PATCH 2/3] perf, ARM: use common PMU interrupt disabled code

Make the ARM perf code use the new common PMU interrupt disabled code.

This allows perf to work on ARM machines without a working PMU
interrupt (for example, raspberry pi).

Signed-off-by: Vince Weaver <vincent.weaver@maine.edu>

diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c
index a6bc431..4238bcb 100644
--- a/arch/arm/kernel/perf_event.c
+++ b/arch/arm/kernel/perf_event.c
@@ -410,7 +410,7 @@ __hw_perf_event_init(struct perf_event *event)
*/
hwc->config_base |= (unsigned long)mapping;

- if (!hwc->sample_period) {
+ if (!is_sampling_event(event)) {
/*
* For non-sampling runs, limit the sample_period to half
* of the counter width. That way, the new counter value
diff --git a/arch/arm/kernel/perf_event_cpu.c b/arch/arm/kernel/perf_event_cpu.c
index 51798d7..63d95fa 100644
--- a/arch/arm/kernel/perf_event_cpu.c
+++ b/arch/arm/kernel/perf_event_cpu.c
@@ -126,8 +126,8 @@ static int cpu_pmu_request_irq(struct arm_pmu *cpu_pmu, irq_handler_t handler)

irqs = min(pmu_device->num_resources, num_possible_cpus());
if (irqs < 1) {
- pr_err("no irqs for PMUs defined\n");
- return -ENODEV;
+ printk_once("no irqs for PMU defined, sampled events not supported\n");
+ return 0;
}

irq = platform_get_irq(pmu_device, 0);
@@ -191,6 +191,11 @@ static void cpu_pmu_init(struct arm_pmu *cpu_pmu)
/* Ensure the PMU has sane values out of reset. */
if (cpu_pmu->reset)
on_each_cpu(cpu_pmu->reset, cpu_pmu, 1);
+
+ /* If no interrupts available, set the corresponding capability flag */
+ if (platform_get_irq(cpu_pmu->plat_device, 0) <= 0) {
+ cpu_pmu->pmu.capabilities |= PERF_PMU_NO_INTERRUPT;
+ }
}

/*

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