drivers/perf: arm_pmu: Always consider IRQ0 as an error

As declared by the chief penguin, and enforced by the NO_IRQ brigade,
IRQ0 doesn't exist, and is considered as an error (no irq).

Unfortunately, the arm_pmu driver still considers it as valid in
a large number of cases. Let's fix this.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c
index c494613..193a68c 100644 (file)
--- a/drivers/perf/arm_pmu.c
+++ b/drivers/perf/arm_pmu.c
@@ -602,7 +602,7 @@ static void cpu_pmu_free_irq(struct arm_pmu *cpu_pmu)
        irqs = min(pmu_device->num_resources, num_possible_cpus());
 
        irq = platform_get_irq(pmu_device, 0);
-       if (irq >= 0 && irq_is_percpu(irq)) {
+       if (irq > 0 && irq_is_percpu(irq)) {
                on_each_cpu_mask(&cpu_pmu->supported_cpus,
                                 cpu_pmu_disable_percpu_irq, &irq, 1);
                free_percpu_irq(irq, &hw_events->percpu_pmu);
@@ -616,7 +616,7 @@ static void cpu_pmu_free_irq(struct arm_pmu *cpu_pmu)
                        if (!cpumask_test_and_clear_cpu(cpu, &cpu_pmu->active_irqs))
                                continue;
                        irq = platform_get_irq(pmu_device, i);
-                       if (irq >= 0)
+                       if (irq > 0)
                                free_irq(irq, per_cpu_ptr(&hw_events->percpu_pmu, cpu));
                }
        }
@@ -638,7 +638,7 @@ static int cpu_pmu_request_irq(struct arm_pmu *cpu_pmu, irq_handler_t handler)
        }
 
        irq = platform_get_irq(pmu_device, 0);
-       if (irq >= 0 && irq_is_percpu(irq)) {
+       if (irq > 0 && irq_is_percpu(irq)) {
                err = request_percpu_irq(irq, handler, "arm-pmu",
                                         &hw_events->percpu_pmu);
                if (err) {
@@ -919,7 +919,7 @@ static int of_pmu_irq_cfg(struct arm_pmu *pmu)
 
                /* Check the IRQ type and prohibit a mix of PPIs and SPIs */
                irq = platform_get_irq(pdev, i);
-               if (irq >= 0) {
+               if (irq > 0) {
                        bool spi = !irq_is_percpu(irq);
 
                        if (i > 0 && spi != using_spi) {
@@ -969,8 +969,7 @@ static int of_pmu_irq_cfg(struct arm_pmu *pmu)
        if (cpumask_weight(&pmu->supported_cpus) == 0) {
                int irq = platform_get_irq(pdev, 0);
 
-               if (irq_is_percpu(irq)) {
-                       /* If using PPIs, check the affinity of the partition */
+               if (irq > 0 && irq_is_percpu(irq)) {
                        int ret;
 
                        ret = irq_get_percpu_devid_partition(irq, &pmu->supported_cpus);