blob: c60961f3ac26fb28d1315d6720d86f121cfa239b [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/memory.h>
#include <common/mini-clist.h>
#include <common/standard.h>
#include <common/time.h>
#include <proto/proxy.h>
#include <proto/task.h>
#include <types/task.h>
// FIXME: check 8bitops.c for faster FLS
#include <import/bitops.h>
#include <import/tree.h>
static struct ultree *stack[LLONGBITS];
struct pool_head *pool2_task, *pool2_tree64;
UL2TREE_HEAD(timer_wq);
void *eternity_queue = NULL;
void *run_queue = NULL;
/* perform minimal intializations, report 0 in case of error, 1 if OK. */
int init_task()
{
pool2_task = create_pool("task", sizeof(struct task), MEM_F_SHARED);
pool2_tree64 = create_pool("tree64", sizeof(struct tree64), MEM_F_SHARED);
return pool2_task && pool2_tree64;
}
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);
}
struct task *_task_wakeup(struct task *t)
{
return __task_wakeup(t);
}
/*
* 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 != NULL)) {
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 date of next event (or eternity).
*
*/
void wake_expired_tasks(struct timeval *next)
{
int slen;
struct task *task;
void *data;
#ifdef WAKE_HINT_CHECK_FIRST
/*
* Hint: tasks are *rarely* expired. So we can try to optimize
* by not scanning the tree at all in most cases. However, this
* code costs 160 more bytes which do not look much useful because
* the performance win is not obvious.
*/
if (likely(timer_wq.data != NULL)) {
task = LIST_ELEM(timer_wq.data, struct task *, qlist);
if (likely(tv_isgt(&task->expire, &now))) {
*next = task->expire;
return;
}
}
/* OK we lose. Let's scan the tree then. */
#endif
tree64_foreach(&timer_wq, data, stack, slen) {
task = LIST_ELEM(data, struct task *, qlist);
if (tv_isgt(&task->expire, &now)) {
*next = task->expire;
return;
}
/*
* 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;
}
}
tv_eternity(next);
return;
}
/*
* This does 4 things :
* - wake up all expired tasks
* - call all runnable tasks
* - call maintain_proxies() to enable/disable the listeners
* - return the date of next event in <next> or eternity.
*
*/
void process_runnable_tasks(struct timeval *next)
{
struct timeval temp;
struct task *t;
void *queue;
wake_expired_tasks(next);
/* 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) {
DLIST_DEL(&t->qlist);
t->qlist.p = NULL;
t->state = TASK_IDLE;
t->process(t, &temp);
tv_bound(next, &temp);
}
/* maintain all proxies in a consistent state. This should quickly
* become a task because it becomes expensive when there are huge
* numbers of proxies. */
maintain_proxies(&temp);
tv_bound(next, &temp);
return;
}
/*
* Local variables:
* c-indent-level: 8
* c-basic-offset: 8
* End:
*/