From: Yicong Yang <yangyicong@xxxxxxxxxxxxx> [ Upstream commit e0dd27ad8af00f147ac3c9de88e0687986afc3ea ] Handle the trace interrupt in the hardirq context, make sure the irq core won't threaded it by declaring IRQF_NO_THREAD and userspace won't balance it by declaring IRQF_NOBALANCING. Otherwise we may violate the synchronization requirements of the perf core, referenced to the change of arm-ccn PMU commit 0811ef7e2f54 ("bus: arm-ccn: fix PMU interrupt flags"). In the interrupt handler we mainly doing 2 things: - Copy the data from the local DMA buffer to the AUX buffer - Commit the data in the AUX buffer Signed-off-by: Yicong Yang <yangyicong@xxxxxxxxxxxxx> Acked-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> [ Fixed commit description to suppress checkpatch warning ] Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx> Link: https://lore.kernel.org/r/20231010084731.30450-3-yangyicong@xxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/hwtracing/ptt/hisi_ptt.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/hwtracing/ptt/hisi_ptt.c b/drivers/hwtracing/ptt/hisi_ptt.c index 4140efd664097..75a8f24fdafee 100644 --- a/drivers/hwtracing/ptt/hisi_ptt.c +++ b/drivers/hwtracing/ptt/hisi_ptt.c @@ -342,9 +342,9 @@ static int hisi_ptt_register_irq(struct hisi_ptt *hisi_ptt) return ret; hisi_ptt->trace_irq = pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ); - ret = devm_request_threaded_irq(&pdev->dev, hisi_ptt->trace_irq, - NULL, hisi_ptt_isr, 0, - DRV_NAME, hisi_ptt); + ret = devm_request_irq(&pdev->dev, hisi_ptt->trace_irq, hisi_ptt_isr, + IRQF_NOBALANCING | IRQF_NO_THREAD, DRV_NAME, + hisi_ptt); if (ret) { pci_err(pdev, "failed to request irq %d, ret = %d\n", hisi_ptt->trace_irq, ret); -- 2.42.0