kernel/time/timer.c

72  * The array level of a newly armed timer depends on the relative expiry
73  * time. The farther the expiry time is away the higher the array level and
77  * expiry of the timers, this implementation removes the need for recascading
79  * implementation of the kernel already violated the 'exact' expiry by adding
80  * slack to the expiry time to provide batched expiration. The granularity
85  * timeout timers (networking, disk I/O ...) are canceled before expiry. If
89  * The only exception to this are networking timers with a small expiry
93  * We don't have cascading anymore. timers with a expiry time above the
513  * Helper function to calculate the array index for a given expiry
522 	 * early. Early expiry can happen due to:  in calc_index()
524 	 * - Truncation of the expiry time in the outer wheel levels  in calc_index()
610 	 * effective expiry time of the timer is required here  in enqueue_timer()
615 		 * Set the next expiry time and kick the CPU so it  in enqueue_timer()
953 	 * If the next expiry value is > jiffies, then we fast forward to  in __forward_timer_base()
954 	 * jiffies otherwise we forward to the next expiry value.  in __forward_timer_base()
1031 		 * timer with this expiry.  in __mod_timer()
1043 		 * just update the expiry time and avoid the whole  in __mod_timer()
1068 		 * timer. If it matches set the expiry to the new value so a  in __mod_timer()
1172  * timer is in any case activated with the new expiry time @expires.
1186  *	  not change the effective expiry time
1211  *	  did not change the effective expiry time such that the
1225  * is the absolute expiry time measured in 'jiffies'. When the timer expires
1329 	 * timer->function == NULL in the expiry code.  in __timer_delete()
1500 		 * Mark the base as contended and grab the expiry lock,  in del_timer_wait_running()
1722 	 * incremented directly before expire_timers was called. But expiry  in expire_timers()
1807  * Store next expiry time in base->next_expiry.