The following commit has been merged into the timers/core branch of tip: Commit-ID: 9c336c9935cff267470bb3aaa85c66fac194b650 Gitweb: https://git.kernel.org/tip/9c336c9935cff267470bb3aaa85c66fac194b650 Author: Jindong Yue <jindong....@nxp.com> AuthorDate: Wed, 31 Mar 2021 16:33:18 +08:00 Committer: Thomas Gleixner <t...@linutronix.de> CommitterDate: Fri, 16 Apr 2021 21:03:50 +02:00
tick/broadcast: Allow late registered device to enter oneshot mode 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....@nxp.com> Signed-off-by: Thomas Gleixner <t...@linutronix.de> Link: https://lore.kernel.org/r/20210331083318.21794-1-jindong....@nxp.com --- kernel/time/tick-broadcast.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index 6ec7855..a440552 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -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(); } /*
