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FROMGIT: tick/broadcast: Allow late registered device to enter oneshot mode

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The broadcast device is switched to oneshot mode when the system switches
to oneshot mode. If a broadcast clock event device is registered after the
system switched to oneshot mode, it will stay in periodic mode forever.

Ensure that a late registered device which is selected as broadcast device
is initialized in oneshot mode when the system already uses oneshot mode.

[ tglx: Massage changelog ]

Signed-off-by: Jindong Yue <jindong.yue@nxp.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210331083318.21794-1-jindong.yue@nxp.com
(cherry picked from commit 9c336c9935
 git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git timers/core)
Signed-off-by: Will Deacon <willdeacon@google.com>
Change-Id: If570b8d396f84add2266150bc85d5c82c45bcb0f
Bug: 185092876
This commit is contained in:
Jindong Yue 2021-03-31 16:33:18 +08:00 • committed by Will Deacon
commit 1e5b2db654
1 changed files with 14 additions and 2 deletions
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16
kernel/time/tick-broadcast.c
View file

@ -107,6 +107,19 @@ void tick_install_broadcast_device(struct clock_event_device *dev)
tick_broadcast_device.evtdev = dev;
if (!cpumask_empty(tick_broadcast_mask))
tick_broadcast_start_periodic(dev);
if (!(dev->features & CLOCK_EVT_FEAT_ONESHOT))
return;
/*
* If the system already runs in oneshot mode, switch the newly
* registered broadcast device to oneshot mode explicitly.
*/
if (tick_broadcast_oneshot_active()) {
tick_broadcast_switch_to_oneshot();
return;
}
/*
* Inform all cpus about this. We might be in a situation
* where we did not switch to oneshot mode because the per cpu
@ -115,8 +128,7 @@ void tick_install_broadcast_device(struct clock_event_device *dev)
* notification the systems stays stuck in periodic mode
* forever.
*/
if (dev->features & CLOCK_EVT_FEAT_ONESHOT)
tick_clock_notify();
tick_clock_notify();
}
/*