Commit b9e5b84a authored by Jan Kiszka's avatar Jan Kiszka Committed by Philippe Gerum
Browse files

ipipe: Call present ack and end handlers for timer irq unconditionally

These steps must be done unconditionally, because if
__ipipe_ack_hrtimer_irq() is called, the tick event will be delivered to
the head domain next, which will neither call ipipe_end() for a tick
event, nor propagate such event to the root stage (at least not using
the same IRQ line).

This plugs a race for timers that are per-CPU but share the same
interrupt number. When setting them up, there is a window where the
first CPU already called ipipe_request_irq, but some other CPU did not
yet ran through grab_timer, thus have ipipe_stolen = 0.

It also solves boot issues with the TSC deadline timer in use.

Based on reasoning provided by Philippe Gerum.
Signed-off-by: Jan Kiszka's avatarJan Kiszka <>
parent 432d2adc
......@@ -367,15 +367,18 @@ static void __ipipe_ack_hrtimer_irq(struct irq_desc *desc)
struct ipipe_timer *timer = __ipipe_raw_cpu_read(percpu_timer);
* Pseudo-IRQs like pipelined IPIs have no descriptor, we have
* to check for this.
if (desc)
if (timer->host_timer->ipipe_stolen) {
if (timer->ack)
if (desc)
if (timer->ack)
if (desc)
static int do_set_oneshot(struct clock_event_device *cdev)
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