ARM: perf: move irq registration into pmu implementation

This patch moves the CPU-specific IRQ registration and parsing code into
the CPU PMU backend. This is required because a PMU may have more than
one interrupt, which in turn can be either PPI (per-cpu) or SPI
(requiring strict affinity setting at the interrupt distributor).

Signed-off-by: Sudeep KarkadaNagesha <Sudeep.KarkadaNagesha@arm.com>
[will: cosmetic edits and reworked interrupt dispatching]
Signed-off-by: Will Deacon <will.deacon@arm.com>

diff --git a/arch/arm/include/asm/pmu.h b/arch/arm/include/asm/pmu.h
index a993ad6..a26170d 100644 (file)
--- a/arch/arm/include/asm/pmu.h
+++ b/arch/arm/include/asm/pmu.h
@@ -78,6 +78,8 @@ struct arm_pmu {
        void            (*start)(void);
        void            (*stop)(void);
        void            (*reset)(void *);
+       int             (*request_irq)(irq_handler_t handler);
+       void            (*free_irq)(void);
        int             (*map_event)(struct perf_event *event);
        int             num_events;
        atomic_t        active_events;

diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c
index 86fd399..93971b1 100644 (file)
--- a/arch/arm/kernel/perf_event.c
+++ b/arch/arm/kernel/perf_event.c
@@ -297,87 +297,39 @@ validate_group(struct perf_event *event)
        return 0;
 }
 
-static irqreturn_t armpmu_platform_irq(int irq, void *dev)
+static irqreturn_t armpmu_dispatch_irq(int irq, void *dev)
 {
        struct arm_pmu *armpmu = (struct arm_pmu *) dev;
        struct platform_device *plat_device = armpmu->plat_device;
        struct arm_pmu_platdata *plat = dev_get_platdata(&plat_device->dev);
 
-       return plat->handle_irq(irq, dev, armpmu->handle_irq);
+       if (plat && plat->handle_irq)
+               return plat->handle_irq(irq, dev, armpmu->handle_irq);
+       else
+               return armpmu->handle_irq(irq, dev);
 }
 
 static void
 armpmu_release_hardware(struct arm_pmu *armpmu)
 {
-       int i, irq, irqs;
-       struct platform_device *pmu_device = armpmu->plat_device;
-
-       irqs = min(pmu_device->num_resources, num_possible_cpus());
-
-       for (i = 0; i < irqs; ++i) {
-               if (!cpumask_test_and_clear_cpu(i, &armpmu->active_irqs))
-                       continue;
-               irq = platform_get_irq(pmu_device, i);
-               if (irq >= 0)
-                       free_irq(irq, armpmu);
-       }
-
-       pm_runtime_put_sync(&pmu_device->dev);
+       armpmu->free_irq();
+       pm_runtime_put_sync(&armpmu->plat_device->dev);
 }
 
 static int
 armpmu_reserve_hardware(struct arm_pmu *armpmu)
 {
-       struct arm_pmu_platdata *plat;
-       irq_handler_t handle_irq;
-       int i, err, irq, irqs;
+       int err;
        struct platform_device *pmu_device = armpmu->plat_device;
 
        if (!pmu_device)
                return -ENODEV;
 
-       plat = dev_get_platdata(&pmu_device->dev);
-       if (plat && plat->handle_irq)
-               handle_irq = armpmu_platform_irq;
-       else
-               handle_irq = armpmu->handle_irq;
-
-       irqs = min(pmu_device->num_resources, num_possible_cpus());
-       if (irqs < 1) {
-               pr_err("no irqs for PMUs defined\n");
-               return -ENODEV;
-       }
-
        pm_runtime_get_sync(&pmu_device->dev);
-
-       for (i = 0; i < irqs; ++i) {
-               err = 0;
-               irq = platform_get_irq(pmu_device, i);
-               if (irq < 0)
-                       continue;
-
-               /*
-                * If we have a single PMU interrupt that we can't shift,
-                * assume that we're running on a uniprocessor machine and
-                * continue. Otherwise, continue without this interrupt.
-                */
-               if (irq_set_affinity(irq, cpumask_of(i)) && irqs > 1) {
-                       pr_warning("unable to set irq affinity (irq=%d, cpu=%u)\n",
-                                   irq, i);
-                       continue;
-               }
-
-               err = request_irq(irq, handle_irq,
-                                 IRQF_DISABLED | IRQF_NOBALANCING,
-                                 "arm-pmu", armpmu);
-               if (err) {
-                       pr_err("unable to request IRQ%d for ARM PMU counters\n",
-                               irq);
-                       armpmu_release_hardware(armpmu);
-                       return err;
-               }
-
-               cpumask_set_cpu(i, &armpmu->active_irqs);
+       err = armpmu->request_irq(armpmu_dispatch_irq);
+       if (err) {
+               armpmu_release_hardware(armpmu);
+               return err;
        }
 
        return 0;

diff --git a/arch/arm/kernel/perf_event_cpu.c b/arch/arm/kernel/perf_event_cpu.c
index 56ddc98..8d7d8d4 100644 (file)
--- a/arch/arm/kernel/perf_event_cpu.c
+++ b/arch/arm/kernel/perf_event_cpu.c
@@ -70,6 +70,67 @@ static struct pmu_hw_events *cpu_pmu_get_cpu_events(void)
        return &__get_cpu_var(cpu_hw_events);
 }
 
+static void cpu_pmu_free_irq(void)
+{
+       int i, irq, irqs;
+       struct platform_device *pmu_device = cpu_pmu->plat_device;
+
+       irqs = min(pmu_device->num_resources, num_possible_cpus());
+
+       for (i = 0; i < irqs; ++i) {
+               if (!cpumask_test_and_clear_cpu(i, &cpu_pmu->active_irqs))
+                       continue;
+               irq = platform_get_irq(pmu_device, i);
+               if (irq >= 0)
+                       free_irq(irq, cpu_pmu);
+       }
+}
+
+static int cpu_pmu_request_irq(irq_handler_t handler)
+{
+       int i, err, irq, irqs;
+       struct platform_device *pmu_device = cpu_pmu->plat_device;
+
+       if (!pmu_device)
+               return -ENODEV;
+
+       irqs = min(pmu_device->num_resources, num_possible_cpus());
+       if (irqs < 1) {
+               pr_err("no irqs for PMUs defined\n");
+               return -ENODEV;
+       }
+
+       for (i = 0; i < irqs; ++i) {
+               err = 0;
+               irq = platform_get_irq(pmu_device, i);
+               if (irq < 0)
+                       continue;
+
+               /*
+                * If we have a single PMU interrupt that we can't shift,
+                * assume that we're running on a uniprocessor machine and
+                * continue. Otherwise, continue without this interrupt.
+                */
+               if (irq_set_affinity(irq, cpumask_of(i)) && irqs > 1) {
+                       pr_warning("unable to set irq affinity (irq=%d, cpu=%u)\n",
+                                   irq, i);
+                       continue;
+               }
+
+               err = request_irq(irq, handler, IRQF_NOBALANCING, "arm-pmu",
+                                 cpu_pmu);
+               if (err) {
+                       pr_err("unable to request IRQ%d for ARM PMU counters\n",
+                               irq);
+                       return err;
+               }
+
+               cpumask_set_cpu(i, &cpu_pmu->active_irqs);
+       }
+
+       return 0;
+}
+
 static void __devinit cpu_pmu_init(struct arm_pmu *cpu_pmu)
 {
        int cpu;
@@ -79,7 +140,10 @@ static void __devinit cpu_pmu_init(struct arm_pmu *cpu_pmu)
                events->used_mask = per_cpu(used_mask, cpu);
                raw_spin_lock_init(&events->pmu_lock);
        }
-       cpu_pmu->get_hw_events = cpu_pmu_get_cpu_events;
+
+       cpu_pmu->get_hw_events  = cpu_pmu_get_cpu_events;
+       cpu_pmu->request_irq    = cpu_pmu_request_irq;
+       cpu_pmu->free_irq       = cpu_pmu_free_irq;
 
        /* Ensure the PMU has sane values out of reset. */
        if (cpu_pmu && cpu_pmu->reset)