irq: Call tick_irq_enter() inside HARDIRQ_OFFSET

Now that account_hardirq_enter() 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 <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20201202115732.27827-6-frederic@kernel.org
This commit is contained in:
Frederic Weisbecker 2020-12-02 12:57:32 +01:00 committed by Thomas Gleixner
parent d3759e7184
commit d14ce74f1f

View File

@ -377,16 +377,12 @@ restart:
*/
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_hardirq_enter(current);
}
/**