diff mbox series

[v2,6/9] arm64: perf: Do not call irq_work_run in NMI context

Message ID 1553271844-49003-7-git-send-email-julien.thierry@arm.com (mailing list archive)
State New, archived
Headers show
Series arm_pmu: Use NMI for perf interrupt | expand

Commit Message

Julien Thierry March 22, 2019, 4:24 p.m. UTC 
Function irq_work_run is not NMI safe and should not be called from NMI
context.

When PMU interrupt is an NMI do not call irq_work_run. Instead rely on the
IRQ work IPI to run the irq_work queue once NMI/IRQ contexts have been
exited.

Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
---
 arch/arm64/kernel/perf_event.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c
index bae4242..316566d 100644
--- a/arch/arm64/kernel/perf_event.c
+++ b/arch/arm64/kernel/perf_event.c
@@ -776,7 +776,8 @@  static irqreturn_t armv8pmu_handle_irq(struct arm_pmu *cpu_pmu)
 	 * platforms that can have the PMU interrupts raised as an NMI, this
 	 * will not work.
 	 */
-	irq_work_run();
+	if (!in_nmi())
+		irq_work_run();
 
 	return IRQ_HANDLED;
 }