From 31d9b3938c0459e5e9755ce0a98ac1e24eeff972 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Sun, 16 Sep 2007 15:36:43 +0200 Subject: [PATCH] clockevents: do not shutdown the oneshot broadcast device When a cpu goes offline it is removed from the broadcast masks. If the mask becomes empty the code shuts down the broadcast device. This is wrong, because the broadcast device needs to be ready for the online cpu going idle (into a c-state, which stops the local apic timer). Signed-off-by: Thomas Gleixner --- kernel/time/tick-broadcast.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index 947959fb2bb5..aab881c86a1a 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -560,20 +560,17 @@ void tick_broadcast_switch_to_oneshot(void) */ void tick_shutdown_broadcast_oneshot(unsigned int *cpup) { - struct clock_event_device *bc; unsigned long flags; unsigned int cpu = *cpup; spin_lock_irqsave(&tick_broadcast_lock, flags); - bc = tick_broadcast_device.evtdev; + /* + * Clear the broadcast mask flag for the dead cpu, but do not + * stop the broadcast device! + */ cpu_clear(cpu, tick_broadcast_oneshot_mask); - if (tick_broadcast_device.mode == TICKDEV_MODE_ONESHOT) { - if (bc && cpus_empty(tick_broadcast_oneshot_mask)) - clockevents_set_mode(bc, CLOCK_EVT_MODE_SHUTDOWN); - } - spin_unlock_irqrestore(&tick_broadcast_lock, flags); } -- GitLab