On Wed, Aug 19, 2020 at 02:34:18PM +0100, Alexandru Elisei wrote:
> From: Julien Thierry <[email protected]>
>
> Currently the PMU interrupt can either be a normal irq or a percpu irq.
> Supporting NMI will introduce two cases for each existing one. It becomes
> a mess of 'if's when managing the interrupt.
>
> Define sets of callbacks for operations commonly done on the interrupt. The
> appropriate set of callbacks is selected at interrupt request time and
> simplifies interrupt enabling/disabling and freeing.
>
> Cc: Julien Thierry <[email protected]>
> Cc: Will Deacon <[email protected]>
> Cc: Mark Rutland <[email protected]>
> Signed-off-by: Julien Thierry <[email protected]>
> Signed-off-by: Alexandru Elisei <[email protected]>
> ---
> drivers/perf/arm_pmu.c | 86 ++++++++++++++++++++++++++++++++++--------
> 1 file changed, 70 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c
> index df352b334ea7..17e5952d21e4 100644
> --- a/drivers/perf/arm_pmu.c
> +++ b/drivers/perf/arm_pmu.c
> @@ -26,8 +26,46 @@
>
> #include <asm/irq_regs.h>
>
> +static int armpmu_count_irq_users(const int irq);
> +
> +struct pmu_irq_ops {
> + void (*enable_pmuirq)(unsigned int irq);
> + void (*disable_pmuirq)(unsigned int irq);
> + void (*free_pmuirq)(unsigned int irq, int cpu, void __percpu *devid);
> +};
> +
> +static void armpmu_free_pmuirq(unsigned int irq, int cpu, void __percpu
> *devid)
> +{
> + free_irq(irq, per_cpu_ptr(devid, cpu));
> +}
> +
> +static const struct pmu_irq_ops pmuirq_ops = {
> + .enable_pmuirq = enable_irq,
> + .disable_pmuirq = disable_irq_nosync,
> + .free_pmuirq = armpmu_free_pmuirq
> +};
> +
> +static void armpmu_enable_percpu_pmuirq(unsigned int irq)
> +{
> + enable_percpu_irq(irq, IRQ_TYPE_NONE);
> +}
> +
> +static void armpmu_free_percpu_pmuirq(unsigned int irq, int cpu,
> + void __percpu *devid)
> +{
> + if (armpmu_count_irq_users(irq) == 1)
> + free_percpu_irq(irq, devid);
> +}
> +
> +static const struct pmu_irq_ops percpu_pmuirq_ops = {
> + .enable_pmuirq = armpmu_enable_percpu_pmuirq,
> + .disable_pmuirq = disable_percpu_irq,
> + .free_pmuirq = armpmu_free_percpu_pmuirq
> +};
> +
> static DEFINE_PER_CPU(struct arm_pmu *, cpu_armpmu);
> static DEFINE_PER_CPU(int, cpu_irq);
> +static DEFINE_PER_CPU(const struct pmu_irq_ops *, cpu_irq_ops);
Would it make sense to put this in a structure alongside the irq?
>
> static inline u64 arm_pmu_event_max_period(struct perf_event *event)
> {
> @@ -544,6 +582,19 @@ static int armpmu_count_irq_users(const int irq)
> return count;
> }
>
> +static const struct pmu_irq_ops *armpmu_find_irq_ops(int irq)
> +{
> + int cpu;
> +
> + for_each_possible_cpu(cpu) {
> + if (per_cpu(cpu_irq, cpu) == irq
> + && per_cpu(cpu_irq_ops, cpu))
> + return per_cpu(cpu_irq_ops, cpu);
> + }
nit, but you could make this a bit more readable:
struct pmu_irq_ops *ops = NULL;
for_each_possible_cpu(cpu) {
if (per_cpu(cpu_irq, cpu) != irq)
continue;
ops = per_cpu(cpu_irq_ops, cpu);
if (ops)
break;
}
return ops;
Will
