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 <npig...@gmail.com>
---
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 efbadcbbf694..df18085de8c4 100644
--- a/arch/powerpc/kernel/irq.c
+++ b/arch/powerpc/kernel/irq.c
@@ -138,6 +138,13 @@ 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;
@@ -292,6 +299,7 @@ notrace void arch_local_irq_restore(unsigned long en)
#endif /* CONFIG_TRACE_IRQFLAGS */
soft_disable_set(IRQS_DISABLED);
+ trace_hardirqs_off();
/*
* Check if anything needs to be re-emitted. We haven't
@@ -301,6 +309,7 @@ notrace void arch_local_irq_restore(unsigned long en)
replay = __check_irq_replay();
/* We can soft-enable now */
+ trace_hardirqs_on();
soft_disable_set(IRQS_ENABLED);
/*
--
2.13.3
