8 #include <linux/posix-timers.h>
20 #include "posix-timers.h"
290  * CPU timers armed. Before starting a timer it's required to check whether
526  * Clean out CPU timers which are still armed when a thread exits. The
527  * timers are only removed from the list. No other updates are done. The
528  * corresponding posix timers are still accessible, but cannot be rearmed.
554  * Insert the timer on the appropriate list before any timers that
569 	 * for process timers we share expiration cache with itimers  in arm_timer()
570 	 * and RLIMIT_CPU and for thread timers with RLIMIT_RTTIME.  in arm_timer()
619  * Guts of sys_timer_settime for CPU timers.
845 		/* Limit the number of timers to expire at once */  in collect_timerqueue()
892  * Check for any per-thread CPU timers that have fired and move them off
894  * tsk->it_*_expires values to reflect the remaining thread CPU timers.
913 	 * Check for the special case thread timers.  in check_thread_timers()
969  * Check for any per-thread CPU timers that have fired and move them
970  * off the tsk->*_timers list onto the firing list.  Per-thread timers
982 	 * If there are no active process wide timers (POSIX 1.b, itimers,  in check_process_timers()
990 	 * Signify that a thread is checking for process timers.  in check_process_timers()
1003 	 * Check for the special case process timers.  in check_process_timers()
1084  * task_cputimers_expired - Check whether posix CPU timers are expired
1105  * fastpath_timer_check - POSIX CPU timers fast path.
1109  * Check the task and thread group timers.  If both are zero (there are no
1110  * timers set) return false.  Otherwise snapshot the task and thread group
1111  * timers and compare them with the corresponding expiration times.  Return
1130 	 * Check if thread group timers expired when timers are active and  in fastpath_timer_check()
1169  * Clear existing posix CPU timers task work.
1185  * Initialize posix CPU timers task work in init task. Out of line to
1209 	/* Schedule task work to actually expire the timers */  in __run_posix_cpu_timers()
1221 	 * timers, so no tick can happen and the fast path check can be  in posix_cpu_timers_enable_work()
1230 	 * On RT enabled kernels ticks can happen while the expired timers  in posix_cpu_timers_enable_work()
1236 	 * advanced since the collecting of expired timers started. If  in posix_cpu_timers_enable_work()
1238 	 * newly expired timers, reenable the fast path check in the timer  in posix_cpu_timers_enable_work()
1239 	 * interrupt. If there are newly expired timers, return false and  in posix_cpu_timers_enable_work()
1291 		 * tsk->cpu_timers[N] all the timers that are firing, and  in handle_posix_cpu_timers()
1300 		 * because nothing can have queued or modified timers after  in handle_posix_cpu_timers()
1306 		 * the loop is not relevant as timers will be directly  in handle_posix_cpu_timers()
1341 	 * Now that all the timers on our list have the firing flag,  in handle_posix_cpu_timers()
1373  * already updated our counts.  We need to check if any timers fire now.
1391 	 * group timers.  If that's so, just return.  in run_posix_cpu_timers()
1400  * Set one of the process-wide special case CPU timers or RLIMIT_CPU.