Message ID | 20220516130500.39586-1-chenjun102@huawei.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | [1/1] perf: hisi: Make irq shared | expand |
On 2022-05-16 14:05, Chen Jun wrote: > On some platforms, there are some error: > genirq: Flags mismatch irq 23. 00010804 (xxx) vs. 00010804 (xxx) > > The reason is that there are more than one pmu nodes using the same > irq number. > > Add IROF_SHARED when devm_request_irq. You really need more than this to share an interrupt between multiple PMUs correctly. Perf relies on IRQs being handled on event->cpu to provide mutual exclusion - if another PMU comes along and moves the interrupt affinity to a different CPU, the interrupt handler may update the event state from that CPU simultaneously with a regular API call on event->cpu also updating it, with potential corruption as a result. For general solutions, one option is to add a layer of explicit interrupt management like arm_dmc620_pmu (FWIW the original idea there was to factor that out into common helpers anyway). It's possible that IRQ affinity notifiers might work as an alternative approach too, but I never got round to looking into that in detail. Thanks, Robin. > Signed-off-by: Chen Jun <chenjun102@huawei.com> > --- > drivers/perf/hisilicon/hisi_uncore_pmu.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/perf/hisilicon/hisi_uncore_pmu.c b/drivers/perf/hisilicon/hisi_uncore_pmu.c > index 358e4e284a62..bcbd3b467f34 100644 > --- a/drivers/perf/hisilicon/hisi_uncore_pmu.c > +++ b/drivers/perf/hisilicon/hisi_uncore_pmu.c > @@ -168,7 +168,7 @@ int hisi_uncore_pmu_init_irq(struct hisi_pmu *hisi_pmu, > return irq; > > ret = devm_request_irq(&pdev->dev, irq, hisi_uncore_pmu_isr, > - IRQF_NOBALANCING | IRQF_NO_THREAD, > + IRQF_NOBALANCING | IRQF_NO_THREAD | IRQF_SHARED, > dev_name(&pdev->dev), hisi_pmu); > if (ret < 0) { > dev_err(&pdev->dev,
diff --git a/drivers/perf/hisilicon/hisi_uncore_pmu.c b/drivers/perf/hisilicon/hisi_uncore_pmu.c index 358e4e284a62..bcbd3b467f34 100644 --- a/drivers/perf/hisilicon/hisi_uncore_pmu.c +++ b/drivers/perf/hisilicon/hisi_uncore_pmu.c @@ -168,7 +168,7 @@ int hisi_uncore_pmu_init_irq(struct hisi_pmu *hisi_pmu, return irq; ret = devm_request_irq(&pdev->dev, irq, hisi_uncore_pmu_isr, - IRQF_NOBALANCING | IRQF_NO_THREAD, + IRQF_NOBALANCING | IRQF_NO_THREAD | IRQF_SHARED, dev_name(&pdev->dev), hisi_pmu); if (ret < 0) { dev_err(&pdev->dev,
On some platforms, there are some error: genirq: Flags mismatch irq 23. 00010804 (xxx) vs. 00010804 (xxx) The reason is that there are more than one pmu nodes using the same irq number. Add IROF_SHARED when devm_request_irq. Signed-off-by: Chen Jun <chenjun102@huawei.com> --- drivers/perf/hisilicon/hisi_uncore_pmu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)