From: Yang Wei <Wei.Yang@xxxxxxxxxxxxx> In RT kernel, I ran into the following calltrace, so PMU interrupts cannot be threaded in_atomic(): 1, irqs_disabled(): 1, pid: 0, name: swapper/0 INFO: lockdep is turned off. Call Trace: [<ffffffff8088595c>] dump_stack+0x1c/0x50 [<ffffffff801a958c>] __might_sleep+0x13c/0x148 [<ffffffff80891c54>] rt_spin_lock+0x3c/0xb0 [<ffffffff801ad29c>] __wake_up+0x3c/0x80 [<ffffffff80243ba4>] perf_event_wakeup+0x8c/0xf8 [<ffffffff80243c50>] perf_pending_event+0x40/0x78 [<ffffffff8023d88c>] irq_work_run+0x74/0xc0 [<ffffffff80152640>] mipsxx_pmu_handle_shared_irq+0x110/0x228 [<ffffffff8015276c>] mipsxx_pmu_handle_irq+0x14/0x30 [<ffffffff801ffda4>] handle_irq_event_percpu+0xbc/0x470 [<ffffffff80204478>] handle_percpu_irq+0x98/0xc8 [<ffffffff801ff284>] generic_handle_irq+0x4c/0x68 [<ffffffff8089748c>] do_IRQ+0x2c/0x48 [<ffffffff80105864>] plat_irq_dispatch+0x64/0xd0 Signed-off-by: Yang Wei <Wei.Yang@xxxxxxxxxxxxx> --- arch/mips/kernel/perf_event_mipsxx.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/mips/kernel/perf_event_mipsxx.c b/arch/mips/kernel/perf_event_mipsxx.c index 811084f..fd16763 100644 --- a/arch/mips/kernel/perf_event_mipsxx.c +++ b/arch/mips/kernel/perf_event_mipsxx.c @@ -550,7 +550,7 @@ static int mipspmu_get_irq(void) if (mipspmu.irq >= 0) { /* Request my own irq handler. */ err = request_irq(mipspmu.irq, mipsxx_pmu_handle_irq, - IRQF_PERCPU | IRQF_NOBALANCING, + IRQF_PERCPU | IRQF_NOBALANCING | IRQF_NO_THREAD, "mips_perf_pmu", NULL); if (err) { pr_warning("Unable to request IRQ%d for MIPS " -- 1.7.9.5