Hi Robin,
On Thu, 1 Jun 2023, Robin Murphy wrote:
On 2023-06-01 04:01, Ilkka Koskinen wrote:
Some of the PMUs may share the interrupt. Support them by
setting IRQF_SHARED
This has the usual problem of allowing any PMU instance to move the IRQ
affinity to a different CPU without also migrating all the other PMU
contexts, and thus breaking perf core's assumptions of mutual exclusion.
I see, I wasn't aware of such an assumption. Sounds like there isn't
necessarily an easy and clean solution for the shared interrupt case. I
drop the patch and get back on the issue if we come up with something
reasonable later.
Cheers, Ilkka
Thanks,
Robin.
Signed-off-by: Ilkka Koskinen <ilkka@xxxxxxxxxxxxxxxxxxxxxx>
---
drivers/perf/arm_cspmu/arm_cspmu.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/perf/arm_cspmu/arm_cspmu.c
b/drivers/perf/arm_cspmu/arm_cspmu.c
index 88547a2b73e6..cc5204d1b5fb 100644
--- a/drivers/perf/arm_cspmu/arm_cspmu.c
+++ b/drivers/perf/arm_cspmu/arm_cspmu.c
@@ -1067,8 +1067,8 @@ static int arm_cspmu_request_irq(struct arm_cspmu
*cspmu)
return irq;
ret = devm_request_irq(dev, irq, arm_cspmu_handle_irq,
- IRQF_NOBALANCING | IRQF_NO_THREAD,
dev_name(dev),
- cspmu);
+ IRQF_NOBALANCING | IRQF_NO_THREAD |
IRQF_SHARED,
+ dev_name(dev), cspmu);
if (ret) {
dev_err(dev, "Could not request IRQ %d\n", irq);
return ret;
