mirror of
https://git.haproxy.org/git/haproxy.git/
synced 2025-08-09 08:37:04 +02:00
Kai Krueger found that previous patch was incomplete, because there is an unconditionnal call to process_srv_queue() in session_free() which still causes a dead server to consume pending connections from the backend. This call was made unconditionnal so that we don't leave unserved connections in the server queue, for instance connections coming in with "option persist" which can bypass the server status check. However, the server must not touch the backend's queue if it is down. Another fear was that some connections might remain unserved when the server is using a dynamic maxconn if the number of connections to the backend is too low. Right now, srv_dynamic_maxconn() ensures this cannot happen, so the call can remain conditionnal. The fix consists in allowing a server to process it own queue whatever its state, but not to touch the backend's queue if it is down. Its queue should normally be empty when the server is down because it is redistributed when the server goes down. The only remaining cases are precisely the persistent connections with "option persist" set, coming in after the queue has been redispatched. Those ones must still be processed when a connection terminates.
83 lines
2.4 KiB
C
83 lines
2.4 KiB
C
/*
|
|
include/proto/queue.h
|
|
This file defines everything related to queues.
|
|
|
|
Copyright (C) 2000-2008 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_QUEUE_H
|
|
#define _PROTO_QUEUE_H
|
|
|
|
#include <common/config.h>
|
|
#include <common/memory.h>
|
|
#include <common/mini-clist.h>
|
|
|
|
#include <types/proxy.h>
|
|
#include <types/queue.h>
|
|
#include <types/session.h>
|
|
#include <types/server.h>
|
|
#include <types/task.h>
|
|
|
|
extern struct pool_head *pool2_pendconn;
|
|
|
|
int init_pendconn();
|
|
struct session *pendconn_get_next_sess(struct server *srv, struct proxy *px);
|
|
struct pendconn *pendconn_add(struct session *sess);
|
|
void pendconn_free(struct pendconn *p);
|
|
void process_srv_queue(struct server *s);
|
|
unsigned int srv_dynamic_maxconn(const struct server *s);
|
|
|
|
|
|
|
|
/* Returns the first pending connection for server <s>, which may be NULL if
|
|
* nothing is pending.
|
|
*/
|
|
static inline struct pendconn *pendconn_from_srv(const struct server *s) {
|
|
if (!s->nbpend)
|
|
return NULL;
|
|
|
|
return LIST_ELEM(s->pendconns.n, struct pendconn *, list);
|
|
}
|
|
|
|
/* Returns the first pending connection for proxy <px>, which may be NULL if
|
|
* nothing is pending.
|
|
*/
|
|
static inline struct pendconn *pendconn_from_px(const struct proxy *px) {
|
|
if (!px->nbpend)
|
|
return NULL;
|
|
|
|
return LIST_ELEM(px->pendconns.n, struct pendconn *, list);
|
|
}
|
|
|
|
/* returns 0 if nothing has to be done for server <s> regarding queued connections,
|
|
* and non-zero otherwise. If the server is down, we only check its own queue. Suited
|
|
* for and if/else usage.
|
|
*/
|
|
static inline int may_dequeue_tasks(const struct server *s, const struct proxy *p) {
|
|
return (s && (s->nbpend || (p->nbpend && (s->state & SRV_RUNNING))) &&
|
|
(!s->maxconn || s->cur_sess < srv_dynamic_maxconn(s)));
|
|
}
|
|
|
|
#endif /* _PROTO_QUEUE_H */
|
|
|
|
/*
|
|
* Local variables:
|
|
* c-indent-level: 8
|
|
* c-basic-offset: 8
|
|
* End:
|
|
*/
|