Now that account_irq_enter_time() is called after HARDIRQ_OFFSET has been incremented, there is nothing left that prevents us from also moving tick_irq_enter() after HARDIRQ_OFFSET is incremented.
The desired outcome is to remove the nasty hack that prevents softirqs from being raised through ksoftirqd instead of the hardirq bottom half. Also tick_irq_enter() then becomes appropriately covered by lockdep. Signed-off-by: Frederic Weisbecker <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Tony Luck <[email protected]> Cc: Fenghua Yu <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Vasily Gorbik <[email protected]> Cc: Christian Borntraeger <[email protected]> --- kernel/softirq.c | 14 +++++--------- 1 file changed, 5 insertions(+), 9 deletions(-) diff --git a/kernel/softirq.c b/kernel/softirq.c index 24254c41bb7c..447ee4d6fe4d 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -377,16 +377,12 @@ asmlinkage __visible void __softirq_entry __do_softirq(void) */ void irq_enter_rcu(void) { - if (is_idle_task(current) && !in_interrupt()) { - /* - * Prevent raise_softirq from needlessly waking up ksoftirqd - * here, as softirq will be serviced on return from interrupt. - */ - local_bh_disable(); + __irq_enter_raw(); + + if (is_idle_task(current) && (irq_count() == HARDIRQ_OFFSET)) tick_irq_enter(); - _local_bh_enable(); - } - __irq_enter(); + + account_irq_enter_time(current); } /** -- 2.25.1
