[PATCH v3 03/51] cpuidle/poll: Ensure IRQ state is invariant

Peter Zijlstra
Thu, 12 Jan 2023 19:43:17 -0000

cpuidle_state::enter() methods should be IRQ invariant.

Additionally make sure to use raw_local_irq_*() methods since this
cpuidle callback will be called with RCU already disabled.

Signed-off-by: Peter Zijlstra (Intel) <peterz at infradead.org>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki at intel.com>
Reviewed-by: Frederic Weisbecker <frederic at kernel.org>
Tested-by: Tony Lindgren <tony at atomide.com>
Tested-by: Ulf Hansson <ulf.hansson at linaro.org>
---
 drivers/cpuidle/poll_state.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/cpuidle/poll_state.c
+++ b/drivers/cpuidle/poll_state.c
@@ -17,7 +17,7 @@ static int __cpuidle poll_idle(struct cp

 	dev->poll_time_limit = false;

-	local_irq_enable();
+	raw_local_irq_enable();
 	if (!current_set_polling_and_test()) {
 		unsigned int loop_count = 0;
 		u64 limit;
@@ -36,6 +36,8 @@ static int __cpuidle poll_idle(struct cp
 			}
 		}
 	}
+	raw_local_irq_disable();
+
 	current_clr_polling();

 	return index;