kernel/time/tick-broadcast.c

4  * device via a broadcast event source.
84  * Check, if the device can be utilized as broadcast device:
161  * Conditionally install/replace broadcast device
188 	 * registered broadcast device to oneshot mode explicitly.
199 	 * of a oneshot capable broadcast device. Without that
207  * Check, if the device is the broadcast device
229 	pr_crit_once("Failed to broadcast timer tick. Some CPUs may be unresponsive.\n");
234 	if (!dev->broadcast)
235 		dev->broadcast = tick_broadcast;
236 	if (!dev->broadcast) {
237 		pr_warn_once("%s depends on broadcast, but no broadcast function available\n",
239 		dev->broadcast = err_broadcast;
245  * needs to be handled by the broadcast device.
258 	 * operated from the broadcast device and is a placeholder for
272 		 * Clear the broadcast bit for this cpu if the
281 		 * Clear the broadcast bit if the CPU is not in
282 		 * periodic broadcast on state.
304 			 * whether the broadcast device can be
310 			 * If we kept the cpu in the broadcast mask,
313 			 * is delivered by the broadcast device, if
314 			 * the broadcast device exists and is not
360 		 * We only run the local handler, if the broadcast
377 		 * have different broadcast functions. For now, just use the
382 		td->evtdev->broadcast(mask);
388  * Periodic broadcast:
389  * - invoke the broadcast handlers
398  * Event handler for periodic broadcast ticks
432  * tick_broadcast_control - Enable/disable or force broadcast mode
433  * @mode:	The selected broadcast mode
473 			 * - the broadcast device exists
474 			 * - the broadcast device is not a hrtimer based one
475 			 * - the broadcast device is in periodic mode to
513  * Set the periodic handler depending on broadcast on/off
515 void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast)
517 	if (!broadcast)
568  * In none of these cases the broadcast device mode can change and the
569  * bit of the resuming CPU in the broadcast mask is safe as well.
621  * broadcast event from the other core is about to happen. We detected
624  * broadcast IPI right away.
636  * Set broadcast interrupt affinity
733 	/* Take care of enforced broadcast requests */
738 	 * Sanity check. Catch the case where we try to broadcast to
785 	 * if we own the broadcast timer.
809 		 * If the current CPU owns the hrtimer broadcast
811 		 * the CPU to the broadcast mask. We don't have to go
820 		 * If the broadcast device is in periodic mode, we
824 			/* If it is a hrtimer based broadcast, return busy */
837 			 * We only reprogram the broadcast timer if we
840 			 * broadcast event. If the current CPU is in
854 				 * us from the broadcast mask and
868 			 * The cpu which was handling the broadcast
869 			 * timer marked this cpu in the broadcast
870 			 * pending mask and fired the broadcast
872 			 * event anyway via the broadcast IPI
887 			 * either the CPU handling the broadcast
890 			 * We are no longer in the broadcast mask, so
896 			 * to idle and therefore rearm the broadcast
905 			 * then we know that the broadcast timer
907 			 * broadcast is about to be handled. So we
909 			 * broadcast handler, which did not run yet,
975 	 * If there is no broadcast or wakeup device, tell the caller not
982  * Reset the one shot broadcast for a cpu
1012 	 * past. The broadcast device which is about to be programmed will
1022  * tick_broadcast_setup_oneshot - setup the broadcast device
1034 	 * When the broadcast device was switched to oneshot by the first
1037 	 * too. Set up the broadcast device only once!
1042 		 * set the broadcast oneshot bit for all other CPUs which
1043 		 * are in the general (periodic) broadcast mask to ensure
1044 		 * that CPUs which wait for the periodic broadcast are
1049 		 * switched to oneshot state to program the broadcast
1068 	 * be ensured that CPUs which are waiting for periodic broadcast
1072 	 * For other callers, e.g. broadcast device replacement,
1076 	 * to update the expiry time and the broadcast event device.
1085 		 * Ensure that the oneshot broadcast handler will wake the
1086 		 * CPUs which are still waiting for periodic broadcast.
1092 		 * If the underlying broadcast clock event device is
1102 	 * When switching from periodic to oneshot mode arm the broadcast
1105 	 * If the broadcast device has been replaced in oneshot mode and
1106 	 * the oneshot broadcast mask is not empty, then arm it to expire
1112 	 * broadcast mask is empty.
1114 	 * tick_broadcast_set_event() implicitly switches the broadcast
1122  * Select oneshot operating mode for the broadcast device
1151 		/* This moves the broadcast assignment to this CPU: */
1166 	 * Clear the broadcast masks for the dead cpu, but do not stop
1167 	 * the broadcast device!
1176  * Check, whether the broadcast device is in one shot mode
1184  * Check whether the broadcast device supports oneshot.