From ff967900c9d4740f6337c6456f111104267633cb Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Sat, 21 Oct 2017 17:56:06 +1000 Subject: [PATCH] powerpc/64: Fix latency tracing for lazy irq replay When returning from an exception to a soft-enabled context, pending IRQs are replayed but IRQ tracing is not reset, so a number of them can get chained together into the same IRQ-disabled trace. Fix this by having __check_irq_replay re-set IRQ trace. This is conceptually where we respond to the next interrupt, so it fits the semantics of the IRQ tracer. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/irq.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c index 6a6995173f51..b7a84522e652 100644 --- a/arch/powerpc/kernel/irq.c +++ b/arch/powerpc/kernel/irq.c @@ -143,6 +143,13 @@ notrace unsigned int __check_irq_replay(void) */ unsigned char happened = local_paca->irq_happened; + /* + * We are responding to the next interrupt, so interrupt-off + * latencies should be reset here. + */ + trace_hardirqs_on(); + trace_hardirqs_off(); + if (happened & PACA_IRQ_HARD_DIS) { /* Clear bit 0 which we wouldn't clear otherwise */ local_paca->irq_happened &= ~PACA_IRQ_HARD_DIS; @@ -270,6 +277,7 @@ notrace void arch_local_irq_restore(unsigned long en) #endif /* CONFIG_TRACE_IRQFLAGS */ set_soft_enabled(0); + trace_hardirqs_off(); /* * Check if anything needs to be re-emitted. We haven't @@ -279,6 +287,7 @@ notrace void arch_local_irq_restore(unsigned long en) replay = __check_irq_replay(); /* We can soft-enable now */ + trace_hardirqs_on(); set_soft_enabled(1); /*