On 2013-11-18 14:18, Vinayak Kale wrote:

On Mon, Nov 18, 2013 at 7:16 PM, Marc Zyngier [off-list ref] 
wrote:

quoted

Vinayak,


On 2013-11-18 13:22, Vinayak Kale wrote:

quoted

Add support for irq registration when pmu interrupt is percpu.

Signed-off-by: Vinayak Kale <redacted>
Signed-off-by: Tuan Phan <redacted>
---
 arch/arm64/kernel/perf_event.c |  102
+++++++++++++++++++++++++++++-----------
 1 file changed, 74 insertions(+), 28 deletions(-)

diff --git a/arch/arm64/kernel/perf_event.c

b/arch/arm64/kernel/perf_event.c
index cea1594..23475f6 100644

--- a/arch/arm64/kernel/perf_event.c
+++ b/arch/arm64/kernel/perf_event.c

@@ -22,6 +22,7 @@

 #include <linux/bitmap.h>
 #include <linux/interrupt.h>
+#include <linux/irq.h>
 #include <linux/kernel.h>
 #include <linux/export.h>
 #include <linux/perf_event.h>

@@ -363,22 +364,51 @@ validate_group(struct perf_event *event)
 }

 static void
+armpmu_disable_percpu_irq(void *data)
+{
+       struct arm_pmu *armpmu = data;
+       struct platform_device *pmu_device = armpmu->plat_device;
+       int irq = platform_get_irq(pmu_device, 0);
+
+       cpumask_test_and_clear_cpu(smp_processor_id(),

&armpmu->active_irqs);
+       disable_percpu_irq(irq);
+}
+
+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());
+       irq = platform_get_irq(pmu_device, 0);

-       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);
+       if (irq_to_desc(irq) && irq_is_percpu(irq)) {

Why do you need to check the irq_desc here? It really looks like a 
misuse of
the API.

I don't think it's being misused. In case of invalid irq number, the
API would return null.

And feeding an error code to irq_to_desc() doesn't disturb you?
Do you call that a normal use of the API? Humfff....

         M.
-- 
Fast, cheap, reliable. Pick two.