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Willy Tarreaubaaee002006-06-26 02:48:02 +02001/*
Willy Tarreau24f4efa2010-08-27 17:56:48 +02002 * include/proto/task.h
3 * Functions for task management.
4 *
5 * Copyright (C) 2000-2010 Willy Tarreau - w@1wt.eu
6 *
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation, version 2.1
10 * exclusively.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with this library; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
Willy Tarreaubaaee002006-06-26 02:48:02 +020021
22#ifndef _PROTO_TASK_H
23#define _PROTO_TASK_H
24
25
26#include <sys/time.h>
Willy Tarreaue3ba5f02006-06-29 18:54:54 +020027
28#include <common/config.h>
Willy Tarreau2dd0d472006-06-29 17:53:05 +020029#include <common/memory.h>
Willy Tarreau96bcfd72007-04-29 10:41:56 +020030#include <common/mini-clist.h>
31#include <common/standard.h>
Willy Tarreaud0a201b2009-03-08 15:53:06 +010032#include <common/ticks.h>
Emeric Brunc60def82017-09-27 14:59:38 +020033#include <common/hathreads.h>
34
Willy Tarreau8d388052017-11-05 13:34:20 +010035#include <eb32sctree.h>
Willy Tarreau45cb4fb2009-10-26 21:10:04 +010036#include <eb32tree.h>
Willy Tarreau96bcfd72007-04-29 10:41:56 +020037
Willy Tarreaueb118892014-11-13 16:57:19 +010038#include <types/global.h>
Willy Tarreaue3ba5f02006-06-29 18:54:54 +020039#include <types/task.h>
Willy Tarreaubaaee002006-06-26 02:48:02 +020040
Willy Tarreaud0a201b2009-03-08 15:53:06 +010041/* Principle of the wait queue.
42 *
43 * We want to be able to tell whether an expiration date is before of after the
44 * current time <now>. We KNOW that expiration dates are never too far apart,
45 * because they are measured in ticks (milliseconds). We also know that almost
46 * all dates will be in the future, and that a very small part of them will be
47 * in the past, they are the ones which have expired since last time we checked
48 * them. Using ticks, we know if a date is in the future or in the past, but we
49 * cannot use that to store sorted information because that reference changes
50 * all the time.
51 *
Willy Tarreaue35c94a2009-03-21 10:01:42 +010052 * We'll use the fact that the time wraps to sort timers. Timers above <now>
53 * are in the future, timers below <now> are in the past. Here, "above" and
54 * "below" are to be considered modulo 2^31.
Willy Tarreaud0a201b2009-03-08 15:53:06 +010055 *
Willy Tarreaue35c94a2009-03-21 10:01:42 +010056 * Timers are stored sorted in an ebtree. We use the new ability for ebtrees to
57 * lookup values starting from X to only expire tasks between <now> - 2^31 and
58 * <now>. If the end of the tree is reached while walking over it, we simply
59 * loop back to the beginning. That way, we have no problem keeping sorted
60 * wrapping timers in a tree, between (now - 24 days) and (now + 24 days). The
61 * keys in the tree always reflect their real position, none can be infinite.
62 * This reduces the number of checks to be performed.
Willy Tarreaud0a201b2009-03-08 15:53:06 +010063 *
64 * Another nice optimisation is to allow a timer to stay at an old place in the
65 * queue as long as it's not further than the real expiration date. That way,
66 * we use the tree as a place holder for a minorant of the real expiration
67 * date. Since we have a very low chance of hitting a timeout anyway, we can
68 * bounce the nodes to their right place when we scan the tree if we encounter
69 * a misplaced node once in a while. This even allows us not to remove the
70 * infinite timers from the wait queue.
71 *
72 * So, to summarize, we have :
73 * - node->key always defines current position in the wait queue
74 * - timer is the real expiration date (possibly infinite)
Willy Tarreaue35c94a2009-03-21 10:01:42 +010075 * - node->key is always before or equal to timer
Willy Tarreaud0a201b2009-03-08 15:53:06 +010076 *
77 * The run queue works similarly to the wait queue except that the current date
78 * is replaced by an insertion counter which can also wrap without any problem.
79 */
80
Willy Tarreaue35c94a2009-03-21 10:01:42 +010081/* The farthest we can look back in a timer tree */
82#define TIMER_LOOK_BACK (1U << 31)
Willy Tarreaud0a201b2009-03-08 15:53:06 +010083
84/* a few exported variables */
Willy Tarreaua4613182009-03-21 18:13:21 +010085extern unsigned int nb_tasks; /* total number of tasks */
Olivier Houchard9b03c0c2018-07-26 18:45:22 +020086extern volatile unsigned long active_tasks_mask; /* Mask of threads with active tasks */
Christopher Faulet34c5cc92016-12-06 09:15:30 +010087extern unsigned int tasks_run_queue; /* run queue size */
88extern unsigned int tasks_run_queue_cur;
Willy Tarreauc7bdf092009-03-21 18:33:52 +010089extern unsigned int nb_tasks_cur;
Willy Tarreau91e99932008-06-30 07:51:00 +020090extern unsigned int niced_tasks; /* number of niced tasks in the run queue */
Willy Tarreaubafbe012017-11-24 17:34:44 +010091extern struct pool_head *pool_head_task;
Olivier Houchardb0bdae72018-05-18 18:45:28 +020092extern struct pool_head *pool_head_tasklet;
Willy Tarreaubafbe012017-11-24 17:34:44 +010093extern struct pool_head *pool_head_notification;
Olivier Houchard9b36cb42018-05-04 15:46:16 +020094extern THREAD_LOCAL struct task *curr_task; /* task currently running or NULL */
95extern THREAD_LOCAL struct eb32sc_node *rq_next; /* Next task to be potentially run */
Olivier Houchardb1ca58b2018-06-06 14:22:03 +020096#ifdef USE_THREAD
Willy Tarreaub20aa9e2018-10-15 14:52:21 +020097extern struct eb_root timers; /* sorted timers tree, global */
Olivier Houchardf6e6dc12018-05-18 18:38:23 +020098extern struct eb_root rqueue; /* tree constituting the run queue */
Olivier Houchard77551ee2018-07-26 15:59:38 +020099extern int global_rqueue_size; /* Number of element sin the global runqueue */
Olivier Houchardb1ca58b2018-06-06 14:22:03 +0200100#endif
Olivier Houchard77551ee2018-07-26 15:59:38 +0200101
Willy Tarreau8d8747a2018-10-15 16:12:48 +0200102/* force to split per-thread stuff into separate cache lines */
103struct task_per_thread {
104 struct eb_root timers; /* tree constituting the per-thread wait queue */
105 struct eb_root rqueue; /* tree constituting the per-thread run queue */
106 struct list task_list; /* List of tasks to be run, mixing tasks and tasklets */
107 int task_list_size; /* Number of tasks in the task_list */
108 int rqueue_size; /* Number of elements in the per-thread run queue */
109 __attribute__((aligned(64))) char end[0];
110};
111
112extern struct task_per_thread task_per_thread[MAX_THREADS];
Christopher Faulet9dcf9b62017-11-13 10:34:01 +0100113
114__decl_hathreads(extern HA_SPINLOCK_T rq_lock); /* spin lock related to run queue */
115__decl_hathreads(extern HA_SPINLOCK_T wq_lock); /* spin lock related to wait queue */
Willy Tarreauc6ca1a02007-05-13 19:43:47 +0200116
Olivier Houchard5d187182018-08-01 15:58:44 +0200117
118static inline void task_insert_into_tasklet_list(struct task *t);
119
Willy Tarreau4726f532009-03-07 17:25:21 +0100120/* return 0 if task is in run queue, otherwise non-zero */
121static inline int task_in_rq(struct task *t)
122{
Olivier Houchardb0bdae72018-05-18 18:45:28 +0200123 /* Check if leaf_p is NULL, in case he's not in the runqueue, and if
124 * it's not 0x1, which would mean it's in the tasklet list.
125 */
126 return t->rq.node.leaf_p != NULL && t->rq.node.leaf_p != (void *)0x1;
Willy Tarreau4726f532009-03-07 17:25:21 +0100127}
128
129/* return 0 if task is in wait queue, otherwise non-zero */
130static inline int task_in_wq(struct task *t)
131{
132 return t->wq.node.leaf_p != NULL;
133}
134
Willy Tarreaufdccded2008-08-29 18:19:04 +0200135/* puts the task <t> in run queue with reason flags <f>, and returns <t> */
Olivier Houchardf6e6dc12018-05-18 18:38:23 +0200136/* This will put the task in the local runqueue if the task is only runnable
137 * by the current thread, in the global runqueue otherwies.
138 */
139void __task_wakeup(struct task *t, struct eb_root *);
140static inline void task_wakeup(struct task *t, unsigned int f)
Willy Tarreau4df82062008-08-29 15:26:14 +0200141{
Olivier Houchardf6e6dc12018-05-18 18:38:23 +0200142 unsigned short state;
Emeric Brunc60def82017-09-27 14:59:38 +0200143
Olivier Houchardf6e6dc12018-05-18 18:38:23 +0200144#ifdef USE_THREAD
145 struct eb_root *root;
Emeric Brunc60def82017-09-27 14:59:38 +0200146
Olivier Houchardb0bdae72018-05-18 18:45:28 +0200147 if (t->thread_mask == tid_bit || global.nbthread == 1)
Willy Tarreau8d8747a2018-10-15 16:12:48 +0200148 root = &task_per_thread[tid].rqueue;
Olivier Houchardf6e6dc12018-05-18 18:38:23 +0200149 else
150 root = &rqueue;
151#else
Willy Tarreau8d8747a2018-10-15 16:12:48 +0200152 struct eb_root *root = &task_per_thread[tid].rqueue;
Olivier Houchardf6e6dc12018-05-18 18:38:23 +0200153#endif
154
155 state = HA_ATOMIC_OR(&t->state, f);
156 if (!(state & TASK_RUNNING))
157 __task_wakeup(t, root);
Willy Tarreau4df82062008-08-29 15:26:14 +0200158}
Willy Tarreaubaaee002006-06-26 02:48:02 +0200159
Willy Tarreauf65610a2017-10-31 16:06:06 +0100160/* change the thread affinity of a task to <thread_mask> */
Emeric Brunc60def82017-09-27 14:59:38 +0200161static inline void task_set_affinity(struct task *t, unsigned long thread_mask)
162{
Willy Tarreauf65610a2017-10-31 16:06:06 +0100163 t->thread_mask = thread_mask;
Emeric Brunc60def82017-09-27 14:59:38 +0200164}
Willy Tarreauf65610a2017-10-31 16:06:06 +0100165
Willy Tarreau4726f532009-03-07 17:25:21 +0100166/*
167 * Unlink the task from the wait queue, and possibly update the last_timer
168 * pointer. A pointer to the task itself is returned. The task *must* already
169 * be in the wait queue before calling this function. If unsure, use the safer
170 * task_unlink_wq() function.
Willy Tarreaubaaee002006-06-26 02:48:02 +0200171 */
Willy Tarreau4726f532009-03-07 17:25:21 +0100172static inline struct task *__task_unlink_wq(struct task *t)
173{
174 eb32_delete(&t->wq);
Willy Tarreau4726f532009-03-07 17:25:21 +0100175 return t;
176}
177
Willy Tarreaub20aa9e2018-10-15 14:52:21 +0200178/* remove a task from its wait queue. It may either be the local wait queue if
179 * the task is bound to a single thread (in which case there's no locking
180 * involved) or the global queue, with locking.
181 */
Willy Tarreau4726f532009-03-07 17:25:21 +0100182static inline struct task *task_unlink_wq(struct task *t)
Willy Tarreaubaaee002006-06-26 02:48:02 +0200183{
Willy Tarreaub20aa9e2018-10-15 14:52:21 +0200184 if (likely(task_in_wq(t))) {
185 if (atleast2(t->thread_mask))
186 HA_SPIN_LOCK(TASK_WQ_LOCK, &wq_lock);
Willy Tarreau4726f532009-03-07 17:25:21 +0100187 __task_unlink_wq(t);
Willy Tarreaub20aa9e2018-10-15 14:52:21 +0200188 if (atleast2(t->thread_mask))
189 HA_SPIN_UNLOCK(TASK_WQ_LOCK, &wq_lock);
190 }
Willy Tarreau96bcfd72007-04-29 10:41:56 +0200191 return t;
Willy Tarreaubaaee002006-06-26 02:48:02 +0200192}
193
194/*
Christopher Faulet34c5cc92016-12-06 09:15:30 +0100195 * Unlink the task from the run queue. The tasks_run_queue size and number of
196 * niced tasks are updated too. A pointer to the task itself is returned. The
197 * task *must* already be in the run queue before calling this function. If
198 * unsure, use the safer task_unlink_rq() function. Note that the pointer to the
199 * next run queue entry is neither checked nor updated.
Willy Tarreaubaaee002006-06-26 02:48:02 +0200200 */
Willy Tarreau4726f532009-03-07 17:25:21 +0100201static inline struct task *__task_unlink_rq(struct task *t)
Willy Tarreaubaaee002006-06-26 02:48:02 +0200202{
Olivier Houchard09eeb762018-05-28 13:51:06 +0200203 HA_ATOMIC_SUB(&tasks_run_queue, 1);
Olivier Houchard77551ee2018-07-26 15:59:38 +0200204#ifdef USE_THREAD
205 if (t->state & TASK_GLOBAL) {
Olivier Houchard76e45182018-07-26 16:19:58 +0200206 HA_ATOMIC_AND(&t->state, ~TASK_GLOBAL);
Olivier Houchard77551ee2018-07-26 15:59:38 +0200207 global_rqueue_size--;
208 } else
209#endif
Willy Tarreau8d8747a2018-10-15 16:12:48 +0200210 task_per_thread[tid].rqueue_size--;
Olivier Houchard77551ee2018-07-26 15:59:38 +0200211 eb32sc_delete(&t->rq);
Willy Tarreau4726f532009-03-07 17:25:21 +0100212 if (likely(t->nice))
Olivier Houchardf6e6dc12018-05-18 18:38:23 +0200213 HA_ATOMIC_SUB(&niced_tasks, 1);
Willy Tarreauce44f122008-07-05 18:16:19 +0200214 return t;
215}
Willy Tarreau9789f7b2008-06-24 08:17:16 +0200216
Willy Tarreau501260b2015-02-23 16:07:01 +0100217/* This function unlinks task <t> from the run queue if it is in it. It also
218 * takes care of updating the next run queue task if it was this task.
219 */
Willy Tarreau4726f532009-03-07 17:25:21 +0100220static inline struct task *task_unlink_rq(struct task *t)
221{
Olivier Houchardf6e6dc12018-05-18 18:38:23 +0200222 if (t->thread_mask != tid_bit)
223 HA_SPIN_LOCK(TASK_RQ_LOCK, &rq_lock);
Olivier Houchard9b36cb42018-05-04 15:46:16 +0200224 if (likely(task_in_rq(t))) {
225 if (&t->rq == rq_next)
226 rq_next = eb32sc_next(rq_next, tid_bit);
Willy Tarreau4726f532009-03-07 17:25:21 +0100227 __task_unlink_rq(t);
Olivier Houchard9b36cb42018-05-04 15:46:16 +0200228 }
Olivier Houchardf6e6dc12018-05-18 18:38:23 +0200229 if (t->thread_mask != tid_bit)
230 HA_SPIN_UNLOCK(TASK_RQ_LOCK, &rq_lock);
Willy Tarreau4726f532009-03-07 17:25:21 +0100231 return t;
232}
233
Olivier Houchardb0bdae72018-05-18 18:45:28 +0200234static inline void tasklet_wakeup(struct tasklet *tl)
235{
Olivier Houchard5d187182018-08-01 15:58:44 +0200236 if (!TASK_IS_TASKLET(tl)) {
237 task_insert_into_tasklet_list((struct task *)tl);
238 return;
239 }
Olivier Houcharde17c2d32018-07-17 18:29:22 +0200240 if (!LIST_ISEMPTY(&tl->list))
241 return;
Willy Tarreau8d8747a2018-10-15 16:12:48 +0200242 LIST_ADDQ(&task_per_thread[tid].task_list, &tl->list);
243 task_per_thread[tid].task_list_size++;
Olivier Houchardabedf5f2018-08-17 18:57:51 +0200244 HA_ATOMIC_OR(&active_tasks_mask, tid_bit);
Olivier Houchardb0bdae72018-05-18 18:45:28 +0200245 HA_ATOMIC_ADD(&tasks_run_queue, 1);
246
247}
248
249static inline void task_insert_into_tasklet_list(struct task *t)
250{
251 struct tasklet *tl;
252 void *expected = NULL;
253
254 /* Protect ourself against anybody trying to insert the task into
255 * another runqueue. We set leaf_p to 0x1 to indicate that the node is
256 * not in a tree but that it's in the tasklet list. See task_in_rq().
257 */
David Carliercaa8a372018-06-01 14:32:39 +0200258 if (unlikely(!HA_ATOMIC_CAS(&t->rq.node.leaf_p, &expected, (void *)0x1)))
Olivier Houchardb0bdae72018-05-18 18:45:28 +0200259 return;
Olivier Houchard09eeb762018-05-28 13:51:06 +0200260 HA_ATOMIC_ADD(&tasks_run_queue, 1);
Willy Tarreau8d8747a2018-10-15 16:12:48 +0200261 task_per_thread[tid].task_list_size++;
Olivier Houchardb0bdae72018-05-18 18:45:28 +0200262 tl = (struct tasklet *)t;
Willy Tarreau8d8747a2018-10-15 16:12:48 +0200263 LIST_ADDQ(&task_per_thread[tid].task_list, &tl->list);
Olivier Houchardb0bdae72018-05-18 18:45:28 +0200264}
265
266static inline void task_remove_from_task_list(struct task *t)
267{
268 LIST_DEL(&((struct tasklet *)t)->list);
Olivier Houcharddcd6f3a2018-06-08 17:08:19 +0200269 LIST_INIT(&((struct tasklet *)t)->list);
Willy Tarreau8d8747a2018-10-15 16:12:48 +0200270 task_per_thread[tid].task_list_size--;
Olivier Houchardb0bdae72018-05-18 18:45:28 +0200271 HA_ATOMIC_SUB(&tasks_run_queue, 1);
272 if (!TASK_IS_TASKLET(t)) {
273 t->rq.node.leaf_p = NULL; // was 0x1
274 __ha_barrier_store();
275 }
276}
277
Willy Tarreauce44f122008-07-05 18:16:19 +0200278/*
279 * Unlinks the task and adjusts run queue stats.
280 * A pointer to the task itself is returned.
281 */
282static inline struct task *task_delete(struct task *t)
283{
Willy Tarreau4726f532009-03-07 17:25:21 +0100284 task_unlink_wq(t);
285 task_unlink_rq(t);
Willy Tarreau9789f7b2008-06-24 08:17:16 +0200286 return t;
287}
288
289/*
Willy Tarreaua4613182009-03-21 18:13:21 +0100290 * Initialize a new task. The bare minimum is performed (queue pointers and
291 * state). The task is returned. This function should not be used outside of
292 * task_new().
Willy Tarreau9789f7b2008-06-24 08:17:16 +0200293 */
Emeric Brunc60def82017-09-27 14:59:38 +0200294static inline struct task *task_init(struct task *t, unsigned long thread_mask)
Willy Tarreau9789f7b2008-06-24 08:17:16 +0200295{
Willy Tarreau4726f532009-03-07 17:25:21 +0100296 t->wq.node.leaf_p = NULL;
297 t->rq.node.leaf_p = NULL;
Olivier Houchardf6e6dc12018-05-18 18:38:23 +0200298 t->state = TASK_SLEEPING;
Willy Tarreauf65610a2017-10-31 16:06:06 +0100299 t->thread_mask = thread_mask;
Willy Tarreau91e99932008-06-30 07:51:00 +0200300 t->nice = 0;
Willy Tarreau3884cba2009-03-28 17:54:35 +0100301 t->calls = 0;
Willy Tarreau9efd7452018-05-31 14:48:54 +0200302 t->call_date = 0;
303 t->cpu_time = 0;
304 t->lat_time = 0;
Willy Tarreauf4219992017-07-24 17:52:58 +0200305 t->expire = TICK_ETERNITY;
Willy Tarreaubaaee002006-06-26 02:48:02 +0200306 return t;
307}
308
Olivier Houchardb0bdae72018-05-18 18:45:28 +0200309static inline void tasklet_init(struct tasklet *t)
310{
311 t->nice = -32768;
312 t->calls = 0;
313 t->state = 0;
Olivier Houchard9ddaf792018-07-19 16:02:16 +0200314 t->process = NULL;
Olivier Houcharddcd6f3a2018-06-08 17:08:19 +0200315 LIST_INIT(&t->list);
Olivier Houchardb0bdae72018-05-18 18:45:28 +0200316}
317
318static inline struct tasklet *tasklet_new(void)
319{
320 struct tasklet *t = pool_alloc(pool_head_tasklet);
321
322 if (t) {
323 tasklet_init(t);
324 }
325 return t;
326}
327
Willy Tarreaubaaee002006-06-26 02:48:02 +0200328/*
Willy Tarreaua4613182009-03-21 18:13:21 +0100329 * Allocate and initialise a new task. The new task is returned, or NULL in
330 * case of lack of memory. The task count is incremented. Tasks should only
331 * be allocated this way, and must be freed using task_free().
332 */
Emeric Brunc60def82017-09-27 14:59:38 +0200333static inline struct task *task_new(unsigned long thread_mask)
Willy Tarreaua4613182009-03-21 18:13:21 +0100334{
Willy Tarreaubafbe012017-11-24 17:34:44 +0100335 struct task *t = pool_alloc(pool_head_task);
Willy Tarreaua4613182009-03-21 18:13:21 +0100336 if (t) {
Emeric Brunc60def82017-09-27 14:59:38 +0200337 HA_ATOMIC_ADD(&nb_tasks, 1);
338 task_init(t, thread_mask);
Willy Tarreaua4613182009-03-21 18:13:21 +0100339 }
340 return t;
341}
342
343/*
344 * Free a task. Its context must have been freed since it will be lost.
345 * The task count is decremented.
Willy Tarreaubaaee002006-06-26 02:48:02 +0200346 */
Olivier Houchard9b36cb42018-05-04 15:46:16 +0200347static inline void __task_free(struct task *t)
Willy Tarreaubaaee002006-06-26 02:48:02 +0200348{
Willy Tarreaubafbe012017-11-24 17:34:44 +0100349 pool_free(pool_head_task, t);
Willy Tarreaueb118892014-11-13 16:57:19 +0100350 if (unlikely(stopping))
Willy Tarreaubafbe012017-11-24 17:34:44 +0100351 pool_flush(pool_head_task);
Emeric Brunc60def82017-09-27 14:59:38 +0200352 HA_ATOMIC_SUB(&nb_tasks, 1);
Willy Tarreaubaaee002006-06-26 02:48:02 +0200353}
354
Olivier Houchard9b36cb42018-05-04 15:46:16 +0200355static inline void task_free(struct task *t)
356{
357 /* There's no need to protect t->state with a lock, as the task
358 * has to run on the current thread.
359 */
360 if (t == curr_task || !(t->state & TASK_RUNNING))
361 __task_free(t);
362 else
363 t->process = NULL;
364}
365
Olivier Houchardb0bdae72018-05-18 18:45:28 +0200366static inline void tasklet_free(struct tasklet *tl)
367{
Olivier Houchard931624a2018-09-12 14:55:03 +0200368 if (!LIST_ISEMPTY(&tl->list))
Willy Tarreau8d8747a2018-10-15 16:12:48 +0200369 task_per_thread[tid].task_list_size--;
Olivier Houcharddcd6f3a2018-06-08 17:08:19 +0200370 LIST_DEL(&tl->list);
371
Olivier Houchardb0bdae72018-05-18 18:45:28 +0200372 pool_free(pool_head_tasklet, tl);
373 if (unlikely(stopping))
374 pool_flush(pool_head_tasklet);
375}
376
Willy Tarreaub20aa9e2018-10-15 14:52:21 +0200377void __task_queue(struct task *task, struct eb_root *wq);
378
Willy Tarreau4726f532009-03-07 17:25:21 +0100379/* Place <task> into the wait queue, where it may already be. If the expiration
Willy Tarreau531cf0c2009-03-08 16:35:27 +0100380 * timer is infinite, do nothing and rely on wake_expired_task to clean up.
Willy Tarreaub20aa9e2018-10-15 14:52:21 +0200381 * If the task is bound to a single thread, it's assumed to be bound to the
382 * current thread's queue and is queued without locking. Otherwise it's queued
383 * into the global wait queue, protected by locks.
Willy Tarreaubaaee002006-06-26 02:48:02 +0200384 */
Willy Tarreau531cf0c2009-03-08 16:35:27 +0100385static inline void task_queue(struct task *task)
386{
387 /* If we already have a place in the wait queue no later than the
388 * timeout we're trying to set, we'll stay there, because it is very
389 * unlikely that we will reach the timeout anyway. If the timeout
390 * has been disabled, it's useless to leave the queue as well. We'll
391 * rely on wake_expired_tasks() to catch the node and move it to the
392 * proper place should it ever happen. Finally we only add the task
393 * to the queue if it was not there or if it was further than what
394 * we want.
395 */
396 if (!tick_isset(task->expire))
397 return;
398
Willy Tarreaub20aa9e2018-10-15 14:52:21 +0200399#ifdef USE_THREAD
400 if (atleast2(task->thread_mask)) {
401 HA_SPIN_LOCK(TASK_WQ_LOCK, &wq_lock);
402 if (!task_in_wq(task) || tick_is_lt(task->expire, task->wq.key))
403 __task_queue(task, &timers);
404 HA_SPIN_UNLOCK(TASK_WQ_LOCK, &wq_lock);
405 } else
406#endif
407 {
408 if (!task_in_wq(task) || tick_is_lt(task->expire, task->wq.key))
Willy Tarreau8d8747a2018-10-15 16:12:48 +0200409 __task_queue(task, &task_per_thread[tid].timers);
Willy Tarreaub20aa9e2018-10-15 14:52:21 +0200410 }
Willy Tarreau531cf0c2009-03-08 16:35:27 +0100411}
Willy Tarreaubaaee002006-06-26 02:48:02 +0200412
Willy Tarreau26e48812011-07-25 14:30:42 +0200413/* Ensure <task> will be woken up at most at <when>. If the task is already in
414 * the run queue (but not running), nothing is done. It may be used that way
415 * with a delay : task_schedule(task, tick_add(now_ms, delay));
416 */
417static inline void task_schedule(struct task *task, int when)
418{
Emeric Brunc60def82017-09-27 14:59:38 +0200419 /* TODO: mthread, check if there is no tisk with this test */
Willy Tarreau26e48812011-07-25 14:30:42 +0200420 if (task_in_rq(task))
421 return;
422
Willy Tarreaub20aa9e2018-10-15 14:52:21 +0200423#ifdef USE_THREAD
424 if (atleast2(task->thread_mask)) {
425 HA_SPIN_LOCK(TASK_WQ_LOCK, &wq_lock);
426 if (task_in_wq(task))
427 when = tick_first(when, task->expire);
428
429 task->expire = when;
430 if (!task_in_wq(task) || tick_is_lt(task->expire, task->wq.key))
431 __task_queue(task, &timers);
432 HA_SPIN_UNLOCK(TASK_WQ_LOCK, &wq_lock);
433 } else
434#endif
435 {
436 if (task_in_wq(task))
437 when = tick_first(when, task->expire);
Willy Tarreau26e48812011-07-25 14:30:42 +0200438
Willy Tarreaub20aa9e2018-10-15 14:52:21 +0200439 task->expire = when;
440 if (!task_in_wq(task) || tick_is_lt(task->expire, task->wq.key))
Willy Tarreau8d8747a2018-10-15 16:12:48 +0200441 __task_queue(task, &task_per_thread[tid].timers);
Willy Tarreaub20aa9e2018-10-15 14:52:21 +0200442 }
Willy Tarreau26e48812011-07-25 14:30:42 +0200443}
444
Thierry FOURNIERd6975962017-07-12 14:31:10 +0200445/* This function register a new signal. "lua" is the current lua
446 * execution context. It contains a pointer to the associated task.
447 * "link" is a list head attached to an other task that must be wake
448 * the lua task if an event occurs. This is useful with external
449 * events like TCP I/O or sleep functions. This funcion allocate
450 * memory for the signal.
451 */
452static inline struct notification *notification_new(struct list *purge, struct list *event, struct task *wakeup)
453{
Willy Tarreaubafbe012017-11-24 17:34:44 +0100454 struct notification *com = pool_alloc(pool_head_notification);
Thierry FOURNIERd6975962017-07-12 14:31:10 +0200455 if (!com)
456 return NULL;
457 LIST_ADDQ(purge, &com->purge_me);
458 LIST_ADDQ(event, &com->wake_me);
Christopher Faulet2a944ee2017-11-07 10:42:54 +0100459 HA_SPIN_INIT(&com->lock);
Thierry FOURNIERd6975962017-07-12 14:31:10 +0200460 com->task = wakeup;
461 return com;
462}
463
464/* This function purge all the pending signals when the LUA execution
465 * is finished. This prevent than a coprocess try to wake a deleted
466 * task. This function remove the memory associated to the signal.
Thierry FOURNIERd5b79832017-12-10 17:14:07 +0100467 * The purge list is not locked because it is owned by only one
468 * process. before browsing this list, the caller must ensure to be
469 * the only one browser.
Thierry FOURNIERd6975962017-07-12 14:31:10 +0200470 */
471static inline void notification_purge(struct list *purge)
472{
473 struct notification *com, *back;
474
475 /* Delete all pending communication signals. */
476 list_for_each_entry_safe(com, back, purge, purge_me) {
Christopher Faulet2a944ee2017-11-07 10:42:54 +0100477 HA_SPIN_LOCK(NOTIF_LOCK, &com->lock);
Thierry FOURNIERd6975962017-07-12 14:31:10 +0200478 LIST_DEL(&com->purge_me);
Thierry FOURNIER738a6d72017-07-17 00:14:07 +0200479 if (!com->task) {
Christopher Faulet2a944ee2017-11-07 10:42:54 +0100480 HA_SPIN_UNLOCK(NOTIF_LOCK, &com->lock);
Willy Tarreaubafbe012017-11-24 17:34:44 +0100481 pool_free(pool_head_notification, com);
Thierry FOURNIER738a6d72017-07-17 00:14:07 +0200482 continue;
483 }
484 com->task = NULL;
Christopher Faulet2a944ee2017-11-07 10:42:54 +0100485 HA_SPIN_UNLOCK(NOTIF_LOCK, &com->lock);
Thierry FOURNIERd6975962017-07-12 14:31:10 +0200486 }
487}
488
Thierry FOURNIERcb146882017-12-10 17:10:57 +0100489/* In some cases, the disconnected notifications must be cleared.
490 * This function just release memory blocs. The purge list is not
491 * locked because it is owned by only one process. Before browsing
492 * this list, the caller must ensure to be the only one browser.
493 * The "com" is not locked because when com->task is NULL, the
494 * notification is no longer used.
495 */
496static inline void notification_gc(struct list *purge)
497{
498 struct notification *com, *back;
499
500 /* Delete all pending communication signals. */
501 list_for_each_entry_safe (com, back, purge, purge_me) {
502 if (com->task)
503 continue;
504 LIST_DEL(&com->purge_me);
505 pool_free(pool_head_notification, com);
506 }
507}
508
Thierry FOURNIERd6975962017-07-12 14:31:10 +0200509/* This function sends signals. It wakes all the tasks attached
510 * to a list head, and remove the signal, and free the used
Thierry FOURNIERd5b79832017-12-10 17:14:07 +0100511 * memory. The wake list is not locked because it is owned by
512 * only one process. before browsing this list, the caller must
513 * ensure to be the only one browser.
Thierry FOURNIERd6975962017-07-12 14:31:10 +0200514 */
515static inline void notification_wake(struct list *wake)
516{
517 struct notification *com, *back;
518
519 /* Wake task and delete all pending communication signals. */
520 list_for_each_entry_safe(com, back, wake, wake_me) {
Christopher Faulet2a944ee2017-11-07 10:42:54 +0100521 HA_SPIN_LOCK(NOTIF_LOCK, &com->lock);
Thierry FOURNIERd6975962017-07-12 14:31:10 +0200522 LIST_DEL(&com->wake_me);
Thierry FOURNIER738a6d72017-07-17 00:14:07 +0200523 if (!com->task) {
Christopher Faulet2a944ee2017-11-07 10:42:54 +0100524 HA_SPIN_UNLOCK(NOTIF_LOCK, &com->lock);
Willy Tarreaubafbe012017-11-24 17:34:44 +0100525 pool_free(pool_head_notification, com);
Thierry FOURNIER738a6d72017-07-17 00:14:07 +0200526 continue;
527 }
Thierry FOURNIERd6975962017-07-12 14:31:10 +0200528 task_wakeup(com->task, TASK_WOKEN_MSG);
Thierry FOURNIER738a6d72017-07-17 00:14:07 +0200529 com->task = NULL;
Christopher Faulet2a944ee2017-11-07 10:42:54 +0100530 HA_SPIN_UNLOCK(NOTIF_LOCK, &com->lock);
Thierry FOURNIERd6975962017-07-12 14:31:10 +0200531 }
532}
533
Thierry FOURNIER9d5422a2018-05-30 11:40:08 +0200534/* This function returns true is some notification are pending
535 */
536static inline int notification_registered(struct list *wake)
537{
538 return !LIST_ISEMPTY(wake);
539}
540
Willy Tarreaubaaee002006-06-26 02:48:02 +0200541/*
Willy Tarreau918ff602011-07-25 16:33:49 +0200542 * This does 3 things :
Willy Tarreaubaaee002006-06-26 02:48:02 +0200543 * - wake up all expired tasks
544 * - call all runnable tasks
Willy Tarreaud825eef2007-05-12 22:35:00 +0200545 * - return the date of next event in <next> or eternity.
Willy Tarreaubaaee002006-06-26 02:48:02 +0200546 */
547
Thierry FOURNIER9cf7c4b2014-12-15 13:26:01 +0100548void process_runnable_tasks();
Willy Tarreaubaaee002006-06-26 02:48:02 +0200549
Willy Tarreau58b458d2008-06-29 22:40:23 +0200550/*
551 * Extract all expired timers from the timer queue, and wakes up all
552 * associated tasks. Returns the date of next event (or eternity).
553 */
Thierry FOURNIER9cf7c4b2014-12-15 13:26:01 +0100554int wake_expired_tasks();
Willy Tarreau58b458d2008-06-29 22:40:23 +0200555
Willy Tarreaubaaee002006-06-26 02:48:02 +0200556#endif /* _PROTO_TASK_H */
557
558/*
559 * Local variables:
560 * c-indent-level: 8
561 * c-basic-offset: 8
562 * End:
563 */