2 This file is part of GNUnet
3 (C) 2009, 2011 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 2, or (at your
8 option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 * @file util/scheduler.c
23 * @brief schedule computations using continuation passing style
24 * @author Christian Grothoff
27 #include "gnunet_common.h"
28 #include "gnunet_os_lib.h"
29 #include "gnunet_scheduler_lib.h"
30 #include "gnunet_signal_lib.h"
31 #include "gnunet_time_lib.h"
34 #define LOG(kind,...) GNUNET_log_from (kind, "util-scheduler", __VA_ARGS__)
36 #define LOG_STRERROR(kind,syscall) GNUNET_log_from_strerror (kind, "util-scheduler", syscall)
43 * Use lsof to generate file descriptor reports on select error?
44 * (turn off for stable releases).
46 #define USE_LSOF GNUNET_NO
49 * Obtain trace information for all scheduler calls that schedule tasks.
51 #define EXECINFO GNUNET_NO
54 * Check each file descriptor before adding
56 #define DEBUG_FDS GNUNET_NO
59 * Depth of the traces collected via EXECINFO.
61 #define MAX_TRACE_DEPTH 50
65 * Should we figure out which tasks are delayed for a while
66 * before they are run? (Consider using in combination with EXECINFO).
68 #define PROFILE_DELAYS GNUNET_NO
71 * Task that were in the queue for longer than this are reported if
72 * PROFILE_DELAYS is active.
74 #define DELAY_THRESHOLD GNUNET_TIME_UNIT_SECONDS
78 * Linked list of pending tasks.
83 * This is a linked list.
88 * Function to run when ready.
90 GNUNET_SCHEDULER_Task callback;
93 * Closure for the callback.
98 * Set of file descriptors this task is waiting
99 * for for reading. Once ready, this is updated
100 * to reflect the set of file descriptors ready
103 struct GNUNET_NETWORK_FDSet *read_set;
106 * Set of file descriptors this task is waiting for for writing.
107 * Once ready, this is updated to reflect the set of file
108 * descriptors ready for operation.
110 struct GNUNET_NETWORK_FDSet *write_set;
113 * Unique task identifier.
115 GNUNET_SCHEDULER_TaskIdentifier id;
118 * Absolute timeout value for the task, or
119 * GNUNET_TIME_UNIT_FOREVER_ABS for "no timeout".
121 struct GNUNET_TIME_Absolute timeout;
125 * When was the task scheduled?
127 struct GNUNET_TIME_Absolute start_time;
131 * Why is the task ready? Set after task is added to ready queue.
132 * Initially set to zero. All reasons that have already been
133 * satisfied (i.e. read or write ready) will be set over time.
135 enum GNUNET_SCHEDULER_Reason reason;
140 enum GNUNET_SCHEDULER_Priority priority;
143 * Set if we only wait for reading from a single FD, otherwise -1.
148 * Set if we only wait for writing to a single FD, otherwise -1.
153 * Should the existence of this task in the queue be counted as
154 * reason to not shutdown the scheduler?
160 * Array of strings which make up a backtrace from the point when this
161 * task was scheduled (essentially, who scheduled the task?)
163 char **backtrace_strings;
166 * Size of the backtrace_strings array
168 int num_backtrace_strings;
176 * List of tasks waiting for an event.
178 static struct Task *pending;
181 * List of tasks waiting ONLY for a timeout event.
182 * Sorted by timeout (earliest first). Used so that
183 * we do not traverse the list of these tasks when
184 * building select sets (we just look at the head
185 * to determine the respective timeout ONCE).
187 static struct Task *pending_timeout;
190 * Last inserted task waiting ONLY for a timeout event.
191 * Used to (heuristically) speed up insertion.
193 static struct Task *pending_timeout_last;
196 * ID of the task that is running right now.
198 static struct Task *active_task;
201 * List of tasks ready to run right now,
202 * grouped by importance.
204 static struct Task *ready[GNUNET_SCHEDULER_PRIORITY_COUNT];
207 * Identity of the last task queued. Incremented for each task to
208 * generate a unique task ID (it is virtually impossible to start
209 * more than 2^64 tasks during the lifetime of a process).
211 static GNUNET_SCHEDULER_TaskIdentifier last_id;
214 * Number of tasks on the ready list.
216 static unsigned int ready_count;
219 * How many tasks have we run so far?
221 static unsigned long long tasks_run;
224 * Priority of the task running right now. Only
225 * valid while a task is running.
227 static enum GNUNET_SCHEDULER_Priority current_priority;
230 * Priority of the highest task added in the current select
233 static enum GNUNET_SCHEDULER_Priority max_priority_added;
236 * Value of the 'lifeness' flag for the current task.
238 static int current_lifeness;
241 * Function to use as a select() in the scheduler.
242 * If NULL, we use GNUNET_NETWORK_socket_select ().
244 static GNUNET_SCHEDULER_select scheduler_select;
247 * Closure for 'scheduler_select'.
249 static void *scheduler_select_cls;
252 * Sets the select function to use in the scheduler (scheduler_select).
254 * @param new_select new select function to use
255 * @param new_select_cls closure for 'new_select'
256 * @return previously used select function, NULL for default
259 GNUNET_SCHEDULER_set_select (GNUNET_SCHEDULER_select new_select,
260 void *new_select_cls)
262 scheduler_select = new_select;
263 scheduler_select_cls = new_select_cls;
268 * Check that the given priority is legal (and return it).
270 * @param p priority value to check
271 * @return p on success, 0 on error
273 static enum GNUNET_SCHEDULER_Priority
274 check_priority (enum GNUNET_SCHEDULER_Priority p)
276 if ((p >= 0) && (p < GNUNET_SCHEDULER_PRIORITY_COUNT))
279 return 0; /* make compiler happy */
284 * Update all sets and timeout for select.
286 * @param rs read-set, set to all FDs we would like to read (updated)
287 * @param ws write-set, set to all FDs we would like to write (updated)
288 * @param timeout next timeout (updated)
291 update_sets (struct GNUNET_NETWORK_FDSet *rs, struct GNUNET_NETWORK_FDSet *ws,
292 struct GNUNET_TIME_Relative *timeout)
295 struct GNUNET_TIME_Absolute now;
296 struct GNUNET_TIME_Relative to;
298 now = GNUNET_TIME_absolute_get ();
299 pos = pending_timeout;
302 to = GNUNET_TIME_absolute_get_difference (now, pos->timeout);
303 if (timeout->rel_value > to.rel_value)
305 if (pos->reason != 0)
306 *timeout = GNUNET_TIME_UNIT_ZERO;
311 if (pos->timeout.abs_value != GNUNET_TIME_UNIT_FOREVER_ABS.abs_value)
313 to = GNUNET_TIME_absolute_get_difference (now, pos->timeout);
314 if (timeout->rel_value > to.rel_value)
317 if (pos->read_fd != -1)
318 GNUNET_NETWORK_fdset_set_native (rs, pos->read_fd);
319 if (pos->write_fd != -1)
320 GNUNET_NETWORK_fdset_set_native (ws, pos->write_fd);
321 if (pos->read_set != NULL)
322 GNUNET_NETWORK_fdset_add (rs, pos->read_set);
323 if (pos->write_set != NULL)
324 GNUNET_NETWORK_fdset_add (ws, pos->write_set);
325 if (pos->reason != 0)
326 *timeout = GNUNET_TIME_UNIT_ZERO;
333 * Check if the ready set overlaps with the set we want to have ready.
334 * If so, update the want set (set all FDs that are ready). If not,
337 * @param ready set that is ready
338 * @param want set that we want to be ready
339 * @return GNUNET_YES if there was some overlap
342 set_overlaps (const struct GNUNET_NETWORK_FDSet *ready,
343 struct GNUNET_NETWORK_FDSet *want)
345 if ((NULL == want) || (NULL == ready))
347 if (GNUNET_NETWORK_fdset_overlap (ready, want))
349 /* copy all over (yes, there maybe unrelated bits,
350 * but this should not hurt well-written clients) */
351 GNUNET_NETWORK_fdset_copy (want, ready);
359 * Check if the given task is eligible to run now.
360 * Also set the reason why it is eligible.
362 * @param task task to check if it is ready
363 * @param now the current time
364 * @param rs set of FDs ready for reading
365 * @param ws set of FDs ready for writing
366 * @return GNUNET_YES if we can run it, GNUNET_NO if not.
369 is_ready (struct Task *task, struct GNUNET_TIME_Absolute now,
370 const struct GNUNET_NETWORK_FDSet *rs,
371 const struct GNUNET_NETWORK_FDSet *ws)
373 enum GNUNET_SCHEDULER_Reason reason;
375 reason = task->reason;
376 if (now.abs_value >= task->timeout.abs_value)
377 reason |= GNUNET_SCHEDULER_REASON_TIMEOUT;
378 if ((0 == (reason & GNUNET_SCHEDULER_REASON_READ_READY)) &&
379 (((task->read_fd != -1) &&
380 (GNUNET_YES == GNUNET_NETWORK_fdset_test_native (rs, task->read_fd))) ||
381 (set_overlaps (rs, task->read_set))))
382 reason |= GNUNET_SCHEDULER_REASON_READ_READY;
383 if ((0 == (reason & GNUNET_SCHEDULER_REASON_WRITE_READY)) &&
384 (((task->write_fd != -1) &&
385 (GNUNET_YES == GNUNET_NETWORK_fdset_test_native (ws, task->write_fd)))
386 || (set_overlaps (ws, task->write_set))))
387 reason |= GNUNET_SCHEDULER_REASON_WRITE_READY;
389 return GNUNET_NO; /* not ready */
390 reason |= GNUNET_SCHEDULER_REASON_PREREQ_DONE;
391 task->reason = reason;
397 * Put a task that is ready for execution into the ready queue.
399 * @param task task ready for execution
402 queue_ready_task (struct Task *task)
404 enum GNUNET_SCHEDULER_Priority p = task->priority;
406 if (0 != (task->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
407 p = GNUNET_SCHEDULER_PRIORITY_SHUTDOWN;
408 task->next = ready[check_priority (p)];
409 ready[check_priority (p)] = task;
415 * Check which tasks are ready and move them
416 * to the respective ready queue.
418 * @param rs FDs ready for reading
419 * @param ws FDs ready for writing
422 check_ready (const struct GNUNET_NETWORK_FDSet *rs,
423 const struct GNUNET_NETWORK_FDSet *ws)
428 struct GNUNET_TIME_Absolute now;
430 now = GNUNET_TIME_absolute_get ();
432 pos = pending_timeout;
436 if (now.abs_value >= pos->timeout.abs_value)
437 pos->reason |= GNUNET_SCHEDULER_REASON_TIMEOUT;
438 if (0 == pos->reason)
440 pending_timeout = next;
441 if (pending_timeout_last == pos)
442 pending_timeout_last = NULL;
443 queue_ready_task (pos);
449 LOG (GNUNET_ERROR_TYPE_DEBUG,
450 "Checking readiness of task: %llu / %p\n",
451 pos->id, pos->callback_cls);
453 if (GNUNET_YES == is_ready (pos, now, rs, ws))
459 queue_ready_task (pos);
470 * Request the shutdown of a scheduler. Marks all currently
471 * pending tasks as ready because of shutdown. This will
472 * cause all tasks to run (as soon as possible, respecting
473 * priorities and prerequisite tasks). Note that tasks
474 * scheduled AFTER this call may still be delayed arbitrarily.
477 GNUNET_SCHEDULER_shutdown ()
482 pos = pending_timeout;
485 pos->reason |= GNUNET_SCHEDULER_REASON_SHUTDOWN;
486 /* we don't move the task into the ready queue yet; check_ready
487 * will do that later, possibly adding additional
488 * readiness-factors */
494 pos->reason |= GNUNET_SCHEDULER_REASON_SHUTDOWN;
495 /* we don't move the task into the ready queue yet; check_ready
496 * will do that later, possibly adding additional
497 * readiness-factors */
500 for (i = 0; i < GNUNET_SCHEDULER_PRIORITY_COUNT; i++)
505 pos->reason |= GNUNET_SCHEDULER_REASON_SHUTDOWN;
506 /* we don't move the task into the ready queue yet; check_ready
507 * will do that later, possibly adding additional
508 * readiness-factors */
516 * Destroy a task (release associated resources)
518 * @param t task to destroy
521 destroy_task (struct Task *t)
523 if (NULL != t->read_set)
524 GNUNET_NETWORK_fdset_destroy (t->read_set);
525 if (NULL != t->write_set)
526 GNUNET_NETWORK_fdset_destroy (t->write_set);
528 GNUNET_free (t->backtrace_strings);
535 * Run at least one task in the highest-priority queue that is not
536 * empty. Keep running tasks until we are either no longer running
537 * "URGENT" tasks or until we have at least one "pending" task (which
538 * may become ready, hence we should select on it). Naturally, if
539 * there are no more ready tasks, we also return.
541 * @param rs FDs ready for reading
542 * @param ws FDs ready for writing
545 run_ready (struct GNUNET_NETWORK_FDSet *rs, struct GNUNET_NETWORK_FDSet *ws)
547 enum GNUNET_SCHEDULER_Priority p;
549 struct GNUNET_SCHEDULER_TaskContext tc;
551 max_priority_added = GNUNET_SCHEDULER_PRIORITY_KEEP;
554 if (ready_count == 0)
556 GNUNET_assert (ready[GNUNET_SCHEDULER_PRIORITY_KEEP] == NULL);
557 /* yes, p>0 is correct, 0 is "KEEP" which should
558 * always be an empty queue (see assertion)! */
559 for (p = GNUNET_SCHEDULER_PRIORITY_COUNT - 1; p > 0; p--)
565 GNUNET_assert (pos != NULL); /* ready_count wrong? */
566 ready[p] = pos->next;
568 if (current_priority != pos->priority)
570 current_priority = pos->priority;
571 (void) GNUNET_OS_set_process_priority (GNUNET_OS_process_current (),
574 current_lifeness = pos->lifeness;
577 if (GNUNET_TIME_absolute_get_duration (pos->start_time).rel_value >
578 DELAY_THRESHOLD.rel_value)
580 LOG (GNUNET_ERROR_TYPE_ERROR, "Task %llu took %llums to be scheduled\n",
583 GNUNET_TIME_absolute_get_duration (pos->start_time).rel_value);
586 tc.reason = pos->reason;
587 tc.read_ready = (pos->read_set == NULL) ? rs : pos->read_set;
588 if ((pos->read_fd != -1) &&
589 (0 != (pos->reason & GNUNET_SCHEDULER_REASON_READ_READY)))
590 GNUNET_NETWORK_fdset_set_native (rs, pos->read_fd);
591 tc.write_ready = (pos->write_set == NULL) ? ws : pos->write_set;
592 if ((pos->write_fd != -1) &&
593 (0 != (pos->reason & GNUNET_SCHEDULER_REASON_WRITE_READY)))
594 GNUNET_NETWORK_fdset_set_native (ws, pos->write_fd);
595 if (((tc.reason & GNUNET_SCHEDULER_REASON_WRITE_READY) != 0) &&
596 (pos->write_fd != -1) &&
597 (!GNUNET_NETWORK_fdset_test_native (ws, pos->write_fd)))
598 GNUNET_abort (); // added to ready in previous select loop!
599 LOG (GNUNET_ERROR_TYPE_DEBUG,
600 "Running task: %llu / %p\n", pos->id,
602 pos->callback (pos->callback_cls, &tc);
606 for (i = 0; i < pos->num_backtrace_strings; i++)
607 LOG (GNUNET_ERROR_TYPE_ERROR, "Task %llu trace %d: %s\n", pos->id, i,
608 pos->backtrace_strings[i]);
614 while ((pending == NULL) || (p >= max_priority_added));
618 * Pipe used to communicate shutdown via signal.
620 static struct GNUNET_DISK_PipeHandle *shutdown_pipe_handle;
623 * Process ID of this process at the time we installed the various
629 * Signal handler called for SIGPIPE.
639 * Signal handler called for signals that should cause us to shutdown.
642 sighandler_shutdown ()
645 int old_errno = errno; /* backup errno */
647 if (getpid () != my_pid)
648 exit (1); /* we have fork'ed since the signal handler was created,
649 * ignore the signal, see https://gnunet.org/vfork discussion */
650 GNUNET_DISK_file_write (GNUNET_DISK_pipe_handle
651 (shutdown_pipe_handle, GNUNET_DISK_PIPE_END_WRITE),
658 * Check if the system is still life. Trigger shutdown if we
659 * have tasks, but none of them give us lifeness.
661 * @return GNUNET_OK to continue the main loop,
671 for (t = pending; NULL != t; t = t->next)
672 if (t->lifeness == GNUNET_YES)
674 for (t = pending_timeout; NULL != t; t = t->next)
675 if (t->lifeness == GNUNET_YES)
677 if ((NULL != pending) || (NULL != pending_timeout))
679 GNUNET_SCHEDULER_shutdown ();
687 * Initialize and run scheduler. This function will return when all
688 * tasks have completed. On systems with signals, receiving a SIGTERM
689 * (and other similar signals) will cause "GNUNET_SCHEDULER_shutdown"
690 * to be run after the active task is complete. As a result, SIGTERM
691 * causes all active tasks to be scheduled with reason
692 * "GNUNET_SCHEDULER_REASON_SHUTDOWN". (However, tasks added
693 * afterwards will execute normally!). Note that any particular signal
694 * will only shut down one scheduler; applications should always only
695 * create a single scheduler.
697 * @param task task to run immediately
698 * @param task_cls closure of task
701 GNUNET_SCHEDULER_run (GNUNET_SCHEDULER_Task task, void *task_cls)
703 struct GNUNET_NETWORK_FDSet *rs;
704 struct GNUNET_NETWORK_FDSet *ws;
705 struct GNUNET_TIME_Relative timeout;
707 struct GNUNET_SIGNAL_Context *shc_int;
708 struct GNUNET_SIGNAL_Context *shc_term;
711 struct GNUNET_SIGNAL_Context *shc_quit;
712 struct GNUNET_SIGNAL_Context *shc_hup;
713 struct GNUNET_SIGNAL_Context *shc_pipe;
715 unsigned long long last_tr;
716 unsigned int busy_wait_warning;
717 const struct GNUNET_DISK_FileHandle *pr;
720 GNUNET_assert (active_task == NULL);
721 rs = GNUNET_NETWORK_fdset_create ();
722 ws = GNUNET_NETWORK_fdset_create ();
723 GNUNET_assert (shutdown_pipe_handle == NULL);
724 shutdown_pipe_handle = GNUNET_DISK_pipe (GNUNET_NO, GNUNET_NO, GNUNET_NO, GNUNET_NO);
725 GNUNET_assert (shutdown_pipe_handle != NULL);
726 pr = GNUNET_DISK_pipe_handle (shutdown_pipe_handle,
727 GNUNET_DISK_PIPE_END_READ);
728 GNUNET_assert (pr != NULL);
730 shc_int = GNUNET_SIGNAL_handler_install (SIGINT, &sighandler_shutdown);
731 shc_term = GNUNET_SIGNAL_handler_install (SIGTERM, &sighandler_shutdown);
733 shc_pipe = GNUNET_SIGNAL_handler_install (SIGPIPE, &sighandler_pipe);
734 shc_quit = GNUNET_SIGNAL_handler_install (SIGQUIT, &sighandler_shutdown);
735 shc_hup = GNUNET_SIGNAL_handler_install (SIGHUP, &sighandler_shutdown);
737 current_priority = GNUNET_SCHEDULER_PRIORITY_DEFAULT;
738 current_lifeness = GNUNET_YES;
739 GNUNET_SCHEDULER_add_continuation (task, task_cls,
740 GNUNET_SCHEDULER_REASON_STARTUP);
741 active_task = (void *) (long) -1; /* force passing of sanity check */
742 GNUNET_SCHEDULER_add_now_with_lifeness (GNUNET_NO,
743 &GNUNET_OS_install_parent_control_handler,
747 busy_wait_warning = 0;
748 while (GNUNET_OK == check_lifeness ())
750 GNUNET_NETWORK_fdset_zero (rs);
751 GNUNET_NETWORK_fdset_zero (ws);
752 timeout = GNUNET_TIME_UNIT_FOREVER_REL;
753 update_sets (rs, ws, &timeout);
754 GNUNET_NETWORK_fdset_handle_set (rs, pr);
757 /* no blocking, more work already ready! */
758 timeout = GNUNET_TIME_UNIT_ZERO;
760 if (NULL == scheduler_select)
761 ret = GNUNET_NETWORK_socket_select (rs, ws, NULL, timeout);
763 ret = scheduler_select (scheduler_select_cls, rs, ws, NULL, timeout);
764 if (ret == GNUNET_SYSERR)
769 LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR, "select");
774 snprintf (lsof, sizeof (lsof), "lsof -p %d", getpid ());
777 if (0 != system (lsof))
778 LOG_STRERROR (GNUNET_ERROR_TYPE_WARNING, "system");
784 if ((ret == 0) && (timeout.rel_value == 0) && (busy_wait_warning > 16))
786 LOG (GNUNET_ERROR_TYPE_WARNING, _("Looks like we're busy waiting...\n"));
787 sleep (1); /* mitigate */
789 check_ready (rs, ws);
791 if (GNUNET_NETWORK_fdset_handle_isset (rs, pr))
793 /* consume the signal */
794 GNUNET_DISK_file_read (pr, &c, sizeof (c));
795 /* mark all active tasks as ready due to shutdown */
796 GNUNET_SCHEDULER_shutdown ();
798 if (last_tr == tasks_run)
805 busy_wait_warning = 0;
808 GNUNET_SIGNAL_handler_uninstall (shc_int);
809 GNUNET_SIGNAL_handler_uninstall (shc_term);
811 GNUNET_SIGNAL_handler_uninstall (shc_pipe);
812 GNUNET_SIGNAL_handler_uninstall (shc_quit);
813 GNUNET_SIGNAL_handler_uninstall (shc_hup);
815 GNUNET_DISK_pipe_close (shutdown_pipe_handle);
816 shutdown_pipe_handle = NULL;
817 GNUNET_NETWORK_fdset_destroy (rs);
818 GNUNET_NETWORK_fdset_destroy (ws);
823 * Obtain the reason code for why the current task was
824 * started. Will return the same value as
825 * the GNUNET_SCHEDULER_TaskContext's reason field.
827 * @return reason(s) why the current task is run
829 enum GNUNET_SCHEDULER_Reason
830 GNUNET_SCHEDULER_get_reason ()
832 GNUNET_assert (active_task != NULL);
833 return active_task->reason;
838 * Get information about the current load of this scheduler. Use this
839 * function to determine if an elective task should be added or simply
840 * dropped (if the decision should be made based on the number of
841 * tasks ready to run).
843 * @param p priority level to look at
844 * @return number of tasks pending right now
847 GNUNET_SCHEDULER_get_load (enum GNUNET_SCHEDULER_Priority p)
852 GNUNET_assert (active_task != NULL);
853 if (p == GNUNET_SCHEDULER_PRIORITY_COUNT)
855 if (p == GNUNET_SCHEDULER_PRIORITY_KEEP)
856 p = current_priority;
858 pos = ready[check_priority (p)];
869 * Cancel the task with the specified identifier.
870 * The task must not yet have run.
872 * @param task id of the task to cancel
873 * @return original closure of the task
876 GNUNET_SCHEDULER_cancel (GNUNET_SCHEDULER_TaskIdentifier task)
880 enum GNUNET_SCHEDULER_Priority p;
884 GNUNET_assert (active_task != NULL);
907 if (pending_timeout_last == t)
908 pending_timeout_last = NULL;
914 if (p >= GNUNET_SCHEDULER_PRIORITY_COUNT)
916 LOG (GNUNET_ERROR_TYPE_ERROR, _("Attempt to cancel dead task %llu!\n"),
917 (unsigned long long) task);
943 pending_timeout = t->next;
953 prev->next = t->next;
955 ret = t->callback_cls;
956 LOG (GNUNET_ERROR_TYPE_DEBUG, "Canceling task: %llu / %p\n", task,
964 * Continue the current execution with the given function. This is
965 * similar to the other "add" functions except that there is no delay
966 * and the reason code can be specified.
968 * @param task main function of the task
969 * @param task_cls closure for 'main'
970 * @param reason reason for task invocation
971 * @param priority priority to use for the task
974 GNUNET_SCHEDULER_add_continuation_with_priority (GNUNET_SCHEDULER_Task task, void *task_cls,
975 enum GNUNET_SCHEDULER_Reason reason,
976 enum GNUNET_SCHEDULER_Priority priority)
981 void *backtrace_array[50];
984 GNUNET_assert (NULL != task);
985 GNUNET_assert ((active_task != NULL) ||
986 (reason == GNUNET_SCHEDULER_REASON_STARTUP));
987 t = GNUNET_malloc (sizeof (struct Task));
989 t->num_backtrace_strings = backtrace (backtrace_array, 50);
990 t->backtrace_strings =
991 backtrace_symbols (backtrace_array, t->num_backtrace_strings);
996 t->callback_cls = task_cls;
999 t->start_time = GNUNET_TIME_absolute_get ();
1002 t->priority = priority;
1003 t->lifeness = current_lifeness;
1004 LOG (GNUNET_ERROR_TYPE_DEBUG, "Adding continuation task: %llu / %p\n", t->id,
1006 queue_ready_task (t);
1011 * Continue the current execution with the given function. This is
1012 * similar to the other "add" functions except that there is no delay
1013 * and the reason code can be specified.
1015 * @param task main function of the task
1016 * @param task_cls closure for 'main'
1017 * @param reason reason for task invocation
1020 GNUNET_SCHEDULER_add_continuation (GNUNET_SCHEDULER_Task task, void *task_cls,
1021 enum GNUNET_SCHEDULER_Reason reason)
1023 GNUNET_SCHEDULER_add_continuation_with_priority (task, task_cls,
1025 GNUNET_SCHEDULER_PRIORITY_DEFAULT);
1030 * Schedule a new task to be run with a specified priority.
1032 * @param prio how important is the new task?
1033 * @param task main function of the task
1034 * @param task_cls closure of task
1035 * @return unique task identifier for the job
1036 * only valid until "task" is started!
1038 GNUNET_SCHEDULER_TaskIdentifier
1039 GNUNET_SCHEDULER_add_with_priority (enum GNUNET_SCHEDULER_Priority prio,
1040 GNUNET_SCHEDULER_Task task, void *task_cls)
1042 return GNUNET_SCHEDULER_add_select (prio,
1043 GNUNET_TIME_UNIT_ZERO, NULL, NULL, task,
1050 * Schedule a new task to be run with a specified delay. The task
1051 * will be scheduled for execution once the delay has expired.
1053 * @param delay when should this operation time out? Use
1054 * GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown"
1055 * @param priority priority to use for the task
1056 * @param task main function of the task
1057 * @param task_cls closure of task
1058 * @return unique task identifier for the job
1059 * only valid until "task" is started!
1061 GNUNET_SCHEDULER_TaskIdentifier
1062 GNUNET_SCHEDULER_add_delayed_with_priority (struct GNUNET_TIME_Relative delay,
1063 enum GNUNET_SCHEDULER_Priority priority,
1064 GNUNET_SCHEDULER_Task task, void *task_cls)
1071 void *backtrace_array[MAX_TRACE_DEPTH];
1074 GNUNET_assert (active_task != NULL);
1075 GNUNET_assert (NULL != task);
1076 t = GNUNET_malloc (sizeof (struct Task));
1078 t->callback_cls = task_cls;
1080 t->num_backtrace_strings = backtrace (backtrace_array, MAX_TRACE_DEPTH);
1081 t->backtrace_strings =
1082 backtrace_symbols (backtrace_array, t->num_backtrace_strings);
1088 t->start_time = GNUNET_TIME_absolute_get ();
1090 t->timeout = GNUNET_TIME_relative_to_absolute (delay);
1091 t->priority = priority;
1092 t->lifeness = current_lifeness;
1093 /* try tail first (optimization in case we are
1094 * appending to a long list of tasks with timeouts) */
1095 prev = pending_timeout_last;
1098 if (prev->timeout.abs_value > t->timeout.abs_value)
1101 pos = prev->next; /* heuristic success! */
1105 /* heuristic failed, do traversal of timeout list */
1106 pos = pending_timeout;
1108 while ((pos != NULL) &&
1109 ((pos->timeout.abs_value <= t->timeout.abs_value) ||
1110 (pos->reason != 0)))
1116 pending_timeout = t;
1120 /* hyper-optimization... */
1121 pending_timeout_last = t;
1123 LOG (GNUNET_ERROR_TYPE_DEBUG, "Adding task: %llu / %p\n", t->id,
1128 for (i = 0; i < t->num_backtrace_strings; i++)
1129 LOG (GNUNET_ERROR_TYPE_DEBUG, "Task %llu trace %d: %s\n", t->id, i,
1130 t->backtrace_strings[i]);
1137 * Schedule a new task to be run with a specified delay. The task
1138 * will be scheduled for execution once the delay has expired. It
1139 * will be run with the DEFAULT priority.
1141 * @param delay when should this operation time out? Use
1142 * GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown"
1143 * @param task main function of the task
1144 * @param task_cls closure of task
1145 * @return unique task identifier for the job
1146 * only valid until "task" is started!
1148 GNUNET_SCHEDULER_TaskIdentifier
1149 GNUNET_SCHEDULER_add_delayed (struct GNUNET_TIME_Relative delay,
1150 GNUNET_SCHEDULER_Task task, void *task_cls)
1152 return GNUNET_SCHEDULER_add_delayed_with_priority (delay,
1153 GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1159 * Schedule a new task to be run as soon as possible. The task
1160 * will be run with the DEFAULT priority.
1162 * @param task main function of the task
1163 * @param task_cls closure of task
1164 * @return unique task identifier for the job
1165 * only valid until "task" is started!
1167 GNUNET_SCHEDULER_TaskIdentifier
1168 GNUNET_SCHEDULER_add_now (GNUNET_SCHEDULER_Task task, void *task_cls)
1170 return GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_ZERO, task, task_cls);
1175 * Schedule a new task to be run as soon as possible with the
1176 * (transitive) ignore-shutdown flag either explicitly set or
1177 * explicitly enabled. This task (and all tasks created from it,
1178 * other than by another call to this function) will either count or
1179 * not count for the 'lifeness' of the process. This API is only
1180 * useful in a few special cases.
1182 * @param lifeness GNUNET_YES if the task counts for lifeness, GNUNET_NO if not.
1183 * @param task main function of the task
1184 * @param task_cls closure of task
1185 * @return unique task identifier for the job
1186 * only valid until "task" is started!
1188 GNUNET_SCHEDULER_TaskIdentifier
1189 GNUNET_SCHEDULER_add_now_with_lifeness (int lifeness,
1190 GNUNET_SCHEDULER_Task task,
1193 GNUNET_SCHEDULER_TaskIdentifier ret;
1196 GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1197 GNUNET_TIME_UNIT_ZERO, NULL, NULL, task,
1199 GNUNET_assert (pending->id == ret);
1200 pending->lifeness = lifeness;
1206 * Schedule a new task to be run with a specified delay or when any of
1207 * the specified file descriptor sets is ready. The delay can be used
1208 * as a timeout on the socket(s) being ready. The task will be
1209 * scheduled for execution once either the delay has expired or any of
1210 * the socket operations is ready. This is the most general
1211 * function of the "add" family. Note that the "prerequisite_task"
1212 * must be satisfied in addition to any of the other conditions. In
1213 * other words, the task will be started when
1215 * (prerequisite-run)
1219 * || shutdown-active )
1222 * @param delay how long should we wait? Use GNUNET_TIME_UNIT_FOREVER_REL for "forever",
1223 * which means that the task will only be run after we receive SIGTERM
1224 * @param priority priority to use
1225 * @param rfd file descriptor we want to read (can be -1)
1226 * @param wfd file descriptors we want to write (can be -1)
1227 * @param task main function of the task
1228 * @param task_cls closure of task
1229 * @return unique task identifier for the job
1230 * only valid until "task" is started!
1233 static GNUNET_SCHEDULER_TaskIdentifier
1234 add_without_sets (struct GNUNET_TIME_Relative delay,
1235 enum GNUNET_SCHEDULER_Priority priority,
1237 GNUNET_SCHEDULER_Task task, void *task_cls)
1242 void *backtrace_array[MAX_TRACE_DEPTH];
1245 GNUNET_assert (active_task != NULL);
1246 GNUNET_assert (NULL != task);
1247 t = GNUNET_malloc (sizeof (struct Task));
1249 t->callback_cls = task_cls;
1251 t->num_backtrace_strings = backtrace (backtrace_array, MAX_TRACE_DEPTH);
1252 t->backtrace_strings =
1253 backtrace_symbols (backtrace_array, t->num_backtrace_strings);
1258 int flags = fcntl (rfd, F_GETFD);
1260 if ((flags == -1) && (errno == EBADF))
1262 LOG (GNUNET_ERROR_TYPE_ERROR, "Got invalid file descriptor %d!\n", rfd);
1266 for (i = 0; i < t->num_backtrace_strings; i++)
1267 LOG (GNUNET_ERROR_TYPE_DEBUG, "Trace: %s\n", t->backtrace_strings[i]);
1274 int flags = fcntl (wfd, F_GETFD);
1276 if (flags == -1 && errno == EBADF)
1278 LOG (GNUNET_ERROR_TYPE_ERROR, "Got invalid file descriptor %d!\n", wfd);
1282 for (i = 0; i < t->num_backtrace_strings; i++)
1283 LOG (GNUNET_ERROR_TYPE_DEBUG, "Trace: %s\n", t->backtrace_strings[i]);
1290 GNUNET_assert (wfd >= -1);
1294 t->start_time = GNUNET_TIME_absolute_get ();
1296 t->timeout = GNUNET_TIME_relative_to_absolute (delay);
1297 t->priority = check_priority ((priority == GNUNET_SCHEDULER_PRIORITY_KEEP) ? current_priority : priority);
1298 t->lifeness = current_lifeness;
1301 max_priority_added = GNUNET_MAX (max_priority_added, t->priority);
1302 LOG (GNUNET_ERROR_TYPE_DEBUG, "Adding task: %llu / %p\n", t->id,
1307 for (i = 0; i < t->num_backtrace_strings; i++)
1308 LOG (GNUNET_ERROR_TYPE_DEBUG, "Task %llu trace %d: %s\n", t->id, i,
1309 t->backtrace_strings[i]);
1318 * Schedule a new task to be run with a specified delay or when the
1319 * specified file descriptor is ready for reading. The delay can be
1320 * used as a timeout on the socket being ready. The task will be
1321 * scheduled for execution once either the delay has expired or the
1322 * socket operation is ready. It will be run with the DEFAULT priority.
1324 * @param delay when should this operation time out? Use
1325 * GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown"
1326 * @param rfd read file-descriptor
1327 * @param task main function of the task
1328 * @param task_cls closure of task
1329 * @return unique task identifier for the job
1330 * only valid until "task" is started!
1332 GNUNET_SCHEDULER_TaskIdentifier
1333 GNUNET_SCHEDULER_add_read_net (struct GNUNET_TIME_Relative delay,
1334 struct GNUNET_NETWORK_Handle *rfd,
1335 GNUNET_SCHEDULER_Task task, void *task_cls)
1337 return GNUNET_SCHEDULER_add_read_net_with_priority (delay,
1338 GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1339 rfd, task, task_cls);
1344 * Schedule a new task to be run with a specified priority and to be
1345 * run after the specified delay or when the specified file descriptor
1346 * is ready for reading. The delay can be used as a timeout on the
1347 * socket being ready. The task will be scheduled for execution once
1348 * either the delay has expired or the socket operation is ready. It
1349 * will be run with the DEFAULT priority.
1351 * @param delay when should this operation time out? Use
1352 * GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown"
1353 * @param priority priority to use for the task
1354 * @param rfd read file-descriptor
1355 * @param task main function of the task
1356 * @param task_cls closure of task
1357 * @return unique task identifier for the job
1358 * only valid until "task" is started!
1360 GNUNET_SCHEDULER_TaskIdentifier
1361 GNUNET_SCHEDULER_add_read_net_with_priority (struct GNUNET_TIME_Relative delay,
1362 enum GNUNET_SCHEDULER_Priority priority,
1363 struct GNUNET_NETWORK_Handle *rfd,
1364 GNUNET_SCHEDULER_Task task, void *task_cls)
1367 struct GNUNET_NETWORK_FDSet *rs;
1368 GNUNET_SCHEDULER_TaskIdentifier ret;
1370 GNUNET_assert (rfd != NULL);
1371 rs = GNUNET_NETWORK_fdset_create ();
1372 GNUNET_NETWORK_fdset_set (rs, rfd);
1374 GNUNET_SCHEDULER_add_select (priority,
1377 GNUNET_NETWORK_fdset_destroy (rs);
1380 return add_without_sets (delay,
1382 GNUNET_NETWORK_get_fd (rfd), -1, task,
1390 * Schedule a new task to be run with a specified delay or when the
1391 * specified file descriptor is ready for writing. The delay can be
1392 * used as a timeout on the socket being ready. The task will be
1393 * scheduled for execution once either the delay has expired or the
1394 * socket operation is ready. It will be run with the priority of
1397 * @param delay when should this operation time out? Use
1398 * GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown"
1399 * @param wfd write file-descriptor
1400 * @param task main function of the task
1401 * @param task_cls closure of task
1402 * @return unique task identifier for the job
1403 * only valid until "task" is started!
1405 GNUNET_SCHEDULER_TaskIdentifier
1406 GNUNET_SCHEDULER_add_write_net (struct GNUNET_TIME_Relative delay,
1407 struct GNUNET_NETWORK_Handle *wfd,
1408 GNUNET_SCHEDULER_Task task, void *task_cls)
1411 struct GNUNET_NETWORK_FDSet *ws;
1412 GNUNET_SCHEDULER_TaskIdentifier ret;
1414 GNUNET_assert (wfd != NULL);
1415 ws = GNUNET_NETWORK_fdset_create ();
1416 GNUNET_NETWORK_fdset_set (ws, wfd);
1418 GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1421 GNUNET_NETWORK_fdset_destroy (ws);
1424 GNUNET_assert (GNUNET_NETWORK_get_fd (wfd) >= 0);
1425 return add_without_sets (delay,
1426 GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1427 -1, GNUNET_NETWORK_get_fd (wfd), task,
1434 * Schedule a new task to be run with a specified delay or when the
1435 * specified file descriptor is ready for reading. The delay can be
1436 * used as a timeout on the socket being ready. The task will be
1437 * scheduled for execution once either the delay has expired or the
1438 * socket operation is ready. It will be run with the DEFAULT priority.
1440 * @param delay when should this operation time out? Use
1441 * GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown"
1442 * @param rfd read file-descriptor
1443 * @param task main function of the task
1444 * @param task_cls closure of task
1445 * @return unique task identifier for the job
1446 * only valid until "task" is started!
1448 GNUNET_SCHEDULER_TaskIdentifier
1449 GNUNET_SCHEDULER_add_read_file (struct GNUNET_TIME_Relative delay,
1450 const struct GNUNET_DISK_FileHandle *rfd,
1451 GNUNET_SCHEDULER_Task task, void *task_cls)
1454 struct GNUNET_NETWORK_FDSet *rs;
1455 GNUNET_SCHEDULER_TaskIdentifier ret;
1457 GNUNET_assert (rfd != NULL);
1458 rs = GNUNET_NETWORK_fdset_create ();
1459 GNUNET_NETWORK_fdset_handle_set (rs, rfd);
1461 GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1464 GNUNET_NETWORK_fdset_destroy (rs);
1469 GNUNET_DISK_internal_file_handle_ (rfd, &fd, sizeof (int));
1470 return add_without_sets (delay,
1471 GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1472 fd, -1, task, task_cls);
1479 * Schedule a new task to be run with a specified delay or when the
1480 * specified file descriptor is ready for writing. The delay can be
1481 * used as a timeout on the socket being ready. The task will be
1482 * scheduled for execution once either the delay has expired or the
1483 * socket operation is ready. It will be run with the DEFAULT priority.
1485 * @param delay when should this operation time out? Use
1486 * GNUNET_TIME_UNIT_FOREVER_REL for "on shutdown"
1487 * @param wfd write file-descriptor
1488 * @param task main function of the task
1489 * @param task_cls closure of task
1490 * @return unique task identifier for the job
1491 * only valid until "task" is started!
1493 GNUNET_SCHEDULER_TaskIdentifier
1494 GNUNET_SCHEDULER_add_write_file (struct GNUNET_TIME_Relative delay,
1495 const struct GNUNET_DISK_FileHandle *wfd,
1496 GNUNET_SCHEDULER_Task task, void *task_cls)
1499 struct GNUNET_NETWORK_FDSet *ws;
1500 GNUNET_SCHEDULER_TaskIdentifier ret;
1502 GNUNET_assert (wfd != NULL);
1503 ws = GNUNET_NETWORK_fdset_create ();
1504 GNUNET_NETWORK_fdset_handle_set (ws, wfd);
1506 GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1509 GNUNET_NETWORK_fdset_destroy (ws);
1514 GNUNET_DISK_internal_file_handle_ (wfd, &fd, sizeof (int));
1515 GNUNET_assert (fd >= 0);
1516 return add_without_sets (delay,
1517 GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1518 -1, fd, task, task_cls);
1526 * Schedule a new task to be run with a specified delay or when any of
1527 * the specified file descriptor sets is ready. The delay can be used
1528 * as a timeout on the socket(s) being ready. The task will be
1529 * scheduled for execution once either the delay has expired or any of
1530 * the socket operations is ready. This is the most general
1531 * function of the "add" family. Note that the "prerequisite_task"
1532 * must be satisfied in addition to any of the other conditions. In
1533 * other words, the task will be started when
1535 * (prerequisite-run)
1539 * || (shutdown-active && run-on-shutdown) )
1542 * @param prio how important is this task?
1543 * @param delay how long should we wait? Use GNUNET_TIME_UNIT_FOREVER_REL for "forever",
1544 * which means that the task will only be run after we receive SIGTERM
1545 * @param rs set of file descriptors we want to read (can be NULL)
1546 * @param ws set of file descriptors we want to write (can be NULL)
1547 * @param task main function of the task
1548 * @param task_cls closure of task
1549 * @return unique task identifier for the job
1550 * only valid until "task" is started!
1552 GNUNET_SCHEDULER_TaskIdentifier
1553 GNUNET_SCHEDULER_add_select (enum GNUNET_SCHEDULER_Priority prio,
1554 struct GNUNET_TIME_Relative delay,
1555 const struct GNUNET_NETWORK_FDSet *rs,
1556 const struct GNUNET_NETWORK_FDSet *ws,
1557 GNUNET_SCHEDULER_Task task, void *task_cls)
1562 void *backtrace_array[MAX_TRACE_DEPTH];
1565 GNUNET_assert (active_task != NULL);
1566 GNUNET_assert (NULL != task);
1567 t = GNUNET_malloc (sizeof (struct Task));
1569 t->callback_cls = task_cls;
1571 t->num_backtrace_strings = backtrace (backtrace_array, MAX_TRACE_DEPTH);
1572 t->backtrace_strings =
1573 backtrace_symbols (backtrace_array, t->num_backtrace_strings);
1579 t->read_set = GNUNET_NETWORK_fdset_create ();
1580 GNUNET_NETWORK_fdset_copy (t->read_set, rs);
1584 t->write_set = GNUNET_NETWORK_fdset_create ();
1585 GNUNET_NETWORK_fdset_copy (t->write_set, ws);
1589 t->start_time = GNUNET_TIME_absolute_get ();
1591 t->timeout = GNUNET_TIME_relative_to_absolute (delay);
1593 check_priority ((prio ==
1594 GNUNET_SCHEDULER_PRIORITY_KEEP) ? current_priority :
1596 t->lifeness = current_lifeness;
1599 max_priority_added = GNUNET_MAX (max_priority_added, t->priority);
1600 LOG (GNUNET_ERROR_TYPE_DEBUG, "Adding task: %llu / %p\n", t->id,
1605 for (i = 0; i < t->num_backtrace_strings; i++)
1606 LOG (GNUNET_ERROR_TYPE_DEBUG, "Task %llu trace %d: %s\n", t->id, i,
1607 t->backtrace_strings[i]);
1612 /* end of scheduler.c */