blob: 2fd6efa2a9a825f26165d07a0387885ed6a09107 [file] [log] [blame]
/*
* Task management functions.
*
* Copyright 2000-2007 Willy Tarreau <w@1wt.eu>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
*/
#include <common/config.h>
#include <common/mini-clist.h>
#include <common/standard.h>
#include <common/time.h>
#include <proto/task.h>
#include <types/task.h>
// FIXME: check 8bitops.c for faster FLS
#include <import/bitops.h>
#include <import/tree.h>
/* FIXME : this should be removed very quickly ! */
extern int maintain_proxies(void);
void **pool_task= NULL;
void **pool_tree64 = NULL;
static struct ultree *stack[LLONGBITS];
UL2TREE_HEAD(timer_wq);
void *eternity_queue = NULL;
void *run_queue = NULL;
struct ultree *ul2tree_insert(struct ultree *root, unsigned long h, unsigned long l)
{
return __ul2tree_insert(root, h, l);
}
void *tree_delete(void *node) {
return __tree_delete(node);
}
/*
* task_queue()
*
* Inserts a task into the wait queue at the position given by its expiration
* date.
*
*/
struct task *task_queue(struct task *task)
{
if (unlikely(task->qlist.p != NULL)) {
DLIST_DEL(&task->qlist);
task->qlist.p = NULL;
}
if (unlikely(task->wq)) {
tree_delete(task->wq);
task->wq = NULL;
}
if (unlikely(tv_iseternity(&task->expire))) {
task->wq = NULL;
DLIST_ADD(eternity_queue, &task->qlist);
return task;
}
task->wq = ul2tree_insert(&timer_wq, task->expire.tv_sec, task->expire.tv_usec);
DLIST_ADD(task->wq->data, &task->qlist);
return task;
}
/*
* Extract all expired timers from the wait queue, and wakes up all
* associated tasks.
* Returns the time to wait for next task (next_time).
*
* FIXME: Use an alternative queue for ETERNITY tasks.
*
*/
int wake_expired_tasks()
{
int slen;
struct task *task;
void *data;
int next_time;
/*
* Hint: tasks are *rarely* expired. So we can try to optimize
* by not scanning the tree at all in most cases.
*/
if (likely(timer_wq.data != NULL)) {
task = LIST_ELEM(timer_wq.data, struct task *, qlist);
if (likely(__tv_isge(&task->expire, &now) > 0))
return tv_ms_remain(&now, &task->expire);
}
/* OK we lose. Let's scan the tree then. */
next_time = TIME_ETERNITY;
tree64_foreach(&timer_wq, data, stack, slen) {
task = LIST_ELEM(data, struct task *, qlist);
if (__tv_isgt(&task->expire, &now)) {
next_time = tv_ms_remain(&now, &task->expire);
break;
}
/*
* OK, all tasks linked to this node will be unlinked, as well
* as the node itself, so we do not need to care about correct
* unlinking.
*/
foreach_dlist_item(task, data, struct task *, qlist) {
DLIST_DEL(&task->qlist);
task->wq = NULL;
DLIST_ADD(run_queue, &task->qlist);
task->state = TASK_RUNNING;
}
}
return next_time;
}
/*
* This does 4 things :
* - wake up all expired tasks
* - call all runnable tasks
* - call maintain_proxies() to enable/disable the listeners
* - return the delay till next event in ms, -1 = wait indefinitely
*
*/
int process_runnable_tasks()
{
int next_time;
int time2;
struct task *t;
void *queue;
next_time = wake_expired_tasks();
/* process each task in the run queue now. Each task may be deleted
* since we only use the run queue's head. Note that any task can be
* woken up by any other task and it will be processed immediately
* after as it will be queued on the run queue's head !
*/
queue = run_queue;
foreach_dlist_item(t, queue, struct task *, qlist) {
int temp_time;
DLIST_DEL(&t->qlist);
t->qlist.p = NULL;
t->state = TASK_IDLE;
temp_time = t->process(t);
next_time = MINTIME(temp_time, next_time);
}
/* maintain all proxies in a consistent state. This should quickly
* become a task because it becomes expensive when there are huge
* numbers of proxies. */
time2 = maintain_proxies();
return MINTIME(time2, next_time);
}
/*
* Local variables:
* c-indent-level: 8
* c-basic-offset: 8
* End:
*/