haproxy/include/proto/applet.h
Willy Tarreau 2104659cd5 MEDIUM: buffer: remove the buffer_wq lock
This lock was only needed to protect the buffer_wq list, but now we have
the mt_list for this. This patch simply turns the buffer_wq list to an
mt_list and gets rid of the lock.

It's worth noting that the whole buffer_wait thing still looks totally
wrong especially in a threaded context: the wakeup_cb() callback is
called synchronously from any thread and may end up calling some
connection code that was not expected to run on a given thread. The
whole thing should probably be reworked to use tasklets instead and be
a bit more centralized.
2020-02-26 10:39:36 +01:00

127 lines
3.7 KiB
C

/*
* include/proto/applet.h
* This file contains applet function prototypes
*
* Copyright (C) 2000-2015 Willy Tarreau - w@1wt.eu
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation, version 2.1
* exclusively.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef _PROTO_APPLET_H
#define _PROTO_APPLET_H
#include <stdlib.h>
#include <common/config.h>
#include <common/memory.h>
#include <common/mini-clist.h>
#include <types/applet.h>
#include <proto/task.h>
extern unsigned int nb_applets;
extern struct pool_head *pool_head_appctx;
struct task *task_run_applet(struct task *t, void *context, unsigned short state);
int appctx_buf_available(void *arg);
/* Initializes all required fields for a new appctx. Note that it does the
* minimum acceptable initialization for an appctx. This means only the
* 3 integer states st0, st1, st2 and the chunk used to gather unfinished
* commands are zeroed
*/
static inline void appctx_init(struct appctx *appctx, unsigned long thread_mask)
{
appctx->st0 = appctx->st1 = appctx->st2 = 0;
appctx->chunk = NULL;
appctx->io_release = NULL;
appctx->thread_mask = thread_mask;
appctx->call_rate.curr_sec = 0;
appctx->call_rate.curr_ctr = 0;
appctx->call_rate.prev_ctr = 0;
appctx->state = 0;
}
/* Tries to allocate a new appctx and initialize its main fields. The appctx
* is returned on success, NULL on failure. The appctx must be released using
* appctx_free(). <applet> is assigned as the applet, but it can be NULL.
*/
static inline struct appctx *appctx_new(struct applet *applet, unsigned long thread_mask)
{
struct appctx *appctx;
appctx = pool_alloc(pool_head_appctx);
if (likely(appctx != NULL)) {
appctx->obj_type = OBJ_TYPE_APPCTX;
appctx->applet = applet;
appctx_init(appctx, thread_mask);
appctx->t = task_new(thread_mask);
if (unlikely(appctx->t == NULL)) {
pool_free(pool_head_appctx, appctx);
return NULL;
}
appctx->t->process = task_run_applet;
appctx->t->context = appctx;
MT_LIST_INIT(&appctx->buffer_wait.list);
appctx->buffer_wait.target = appctx;
appctx->buffer_wait.wakeup_cb = appctx_buf_available;
_HA_ATOMIC_ADD(&nb_applets, 1);
}
return appctx;
}
/* Releases an appctx previously allocated by appctx_new(). */
static inline void __appctx_free(struct appctx *appctx)
{
task_destroy(appctx->t);
if (MT_LIST_ADDED(&appctx->buffer_wait.list))
MT_LIST_DEL(&appctx->buffer_wait.list);
pool_free(pool_head_appctx, appctx);
_HA_ATOMIC_SUB(&nb_applets, 1);
}
static inline void appctx_free(struct appctx *appctx)
{
/* The task is supposed to be run on this thread, so we can just
* check if it's running already (or about to run) or not
*/
if (!(appctx->t->state & (TASK_QUEUED | TASK_RUNNING)))
__appctx_free(appctx);
else {
/* if it's running, or about to run, defer the freeing
* until the callback is called.
*/
appctx->state |= APPLET_WANT_DIE;
task_wakeup(appctx->t, TASK_WOKEN_OTHER);
}
}
/* wakes up an applet when conditions have changed */
static inline void appctx_wakeup(struct appctx *appctx)
{
task_wakeup(appctx->t, TASK_WOKEN_OTHER);
}
#endif /* _PROTO_APPLET_H */
/*
* Local variables:
* c-indent-level: 8
* c-basic-offset: 8
* End:
*/