On Fri, May 16, 2014 at 10:15:49PM +0100, Vince Weaver wrote:
>
> 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.wea...@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");
s/sampled/sampling/
> + 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) {
I think you can just do if (!platform_get_irq(cpu_pmu->plat_device, 0))
here (I appreciate the ARM perf code isn't consistent here).
Anyway, with those minor changes:
Acked-by: Will Deacon <will.dea...@arm.com>
Thanks,
Will
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
