haproxy/src/protocol.c
Aurelien DARRAGON d3ffba4512 MINOR: listener: pause_listener() becomes suspend_listener()
We are simply renaming pause_listener() to suspend_listener() to prevent
confusion around listener pausing.

A suspended listener can be in two differents valid states:
 - LI_PAUSED: the listener is effectively paused, it will unpause on
   resume_listener()
 - LI_ASSIGNED (not bound): the listener does not support the LI_PAUSED
   state, so it was unbound to satisfy the suspend request, it will
   correcly re-bind on resume_listener()

Besides that, we add the LI_F_SUSPENDED flag to mark suspended listeners in
suspend_listener() and unmark them in resume_listener().

We're also adding li_suspend proxy variable to track the number of currently
suspended listeners:
That is, the number of listeners that were suspended through suspend_listener()
and that are either in LI_PAUSED or LI_ASSIGNED state.

Counter is increased on successful suspend in suspend_listener() and it is
decreased on successful resume in resume_listener()

--
Backport notes:

-> 2.4 only, as "MINOR: proxy/listener: support for additional PAUSED state"
was not backported:

Replace this:

    |                /* PROXY_LOCK is require
    |                proxy_cond_resume(px);

By this:

    |                ha_warning("Resumed %s %s.\n", proxy_cap_str(px->cap), px->id);
    |                send_log(px, LOG_WARNING, "Resumed %s %s.\n", proxy_cap_str(px->cap), px->id);

-> 2.6 and 2.7 only, as "MINOR: listener: make sure we don't pause/resume" was
custom patched:

Replace this:

    |@@ -253,6 +253,7 @@ struct listener {
    |
    | /* listener flags (16 bits) */
    | #define LI_F_FINALIZED           0x0001  /* listener made it to the READY||LIMITED||FULL state at least once, may be suspended/resumed safely */
    |+#define LI_F_SUSPENDED           0x0002  /* listener has been suspended using suspend_listener(), it is either is LI_PAUSED or LI_ASSIGNED state */
    |
    | /* Descriptor for a "bind" keyword. The ->parse() function returns 0 in case of
    |  * success, or a combination of ERR_* flags if an error is encountered. The

By this:

    |@@ -222,6 +222,7 @@ struct li_per_thread {
    |
    | #define LI_F_QUIC_LISTENER       0x00000001  /* listener uses proto quic */
    | #define LI_F_FINALIZED           0x00000002  /* listener made it to the READY||LIMITED||FULL state at least once, may be suspended/resumed safely */
    |+#define LI_F_SUSPENDED           0x00000004  /* listener has been suspended using suspend_listener(), it is either is LI_PAUSED or LI_ASSIGNED state */
    |
    | /* The listener will be directly referenced by the fdtab[] which holds its
    |  * socket. The listener provides the protocol-specific accept() function to
2023-02-23 15:05:05 +01:00

245 lines
7.0 KiB
C

/*
* Protocol registration functions.
*
* Copyright 2000-2012 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 <sys/types.h>
#include <sys/socket.h>
#include <haproxy/api.h>
#include <haproxy/errors.h>
#include <haproxy/global.h>
#include <haproxy/list.h>
#include <haproxy/listener.h>
#include <haproxy/proto_quic.h>
#include <haproxy/protocol.h>
#include <haproxy/proxy.h>
#include <haproxy/tools.h>
/* List head of all registered protocols */
static struct list protocols = LIST_HEAD_INIT(protocols);
struct protocol *__protocol_by_family[AF_CUST_MAX][PROTO_NUM_TYPES][2] __read_mostly = { };
/* This is the global spinlock we may need to register/unregister listeners or
* protocols. Its main purpose is in fact to serialize the rare stop/deinit()
* phases.
*/
__decl_spinlock(proto_lock);
/* Registers the protocol <proto> */
void protocol_register(struct protocol *proto)
{
int sock_domain = proto->fam->sock_domain;
BUG_ON(sock_domain < 0 || sock_domain >= AF_CUST_MAX);
BUG_ON(proto->proto_type >= PROTO_NUM_TYPES);
HA_SPIN_LOCK(PROTO_LOCK, &proto_lock);
LIST_APPEND(&protocols, &proto->list);
__protocol_by_family[sock_domain]
[proto->proto_type]
[proto->xprt_type == PROTO_TYPE_DGRAM] = proto;
HA_SPIN_UNLOCK(PROTO_LOCK, &proto_lock);
}
/* Unregisters the protocol <proto>. Note that all listeners must have
* previously been unbound.
*/
void protocol_unregister(struct protocol *proto)
{
HA_SPIN_LOCK(PROTO_LOCK, &proto_lock);
LIST_DELETE(&proto->list);
LIST_INIT(&proto->list);
HA_SPIN_UNLOCK(PROTO_LOCK, &proto_lock);
}
/* binds all listeners of all registered protocols. Returns a composition
* of ERR_NONE, ERR_RETRYABLE, ERR_FATAL.
*/
int protocol_bind_all(int verbose)
{
struct protocol *proto;
struct listener *listener;
struct receiver *receiver;
char msg[1000];
char *errmsg;
int err, lerr;
err = 0;
HA_SPIN_LOCK(PROTO_LOCK, &proto_lock);
list_for_each_entry(proto, &protocols, list) {
list_for_each_entry(receiver, &proto->receivers, proto_list) {
#ifdef USE_QUIC
if ((global.tune.options & GTUNE_NO_QUIC) &&
(proto == &proto_quic4 || proto == &proto_quic6))
continue;
#endif
listener = LIST_ELEM(receiver, struct listener *, rx);
lerr = proto->fam->bind(receiver, &errmsg);
err |= lerr;
/* errors are reported if <verbose> is set or if they are fatal */
if (verbose || (lerr & (ERR_FATAL | ERR_ABORT))) {
struct proxy *px = listener->bind_conf->frontend;
if (lerr & ERR_ALERT)
ha_alert("Binding [%s:%d] for %s %s: %s\n",
listener->bind_conf->file, listener->bind_conf->line,
proxy_type_str(px), px->id, errmsg);
else if (lerr & ERR_WARN)
ha_warning("Binding [%s:%d] for %s %s: %s\n",
listener->bind_conf->file, listener->bind_conf->line,
proxy_type_str(px), px->id, errmsg);
}
if (lerr != ERR_NONE)
ha_free(&errmsg);
if (lerr & ERR_ABORT)
break;
if (lerr & ~ERR_WARN)
continue;
/* for now there's still always a listening function */
BUG_ON(!proto->listen);
lerr = proto->listen(listener, msg, sizeof(msg));
err |= lerr;
if (verbose || (lerr & (ERR_FATAL | ERR_ABORT))) {
struct proxy *px = listener->bind_conf->frontend;
if (lerr & ERR_ALERT)
ha_alert("Starting [%s:%d] for %s %s: %s\n",
listener->bind_conf->file, listener->bind_conf->line,
proxy_type_str(px), px->id, msg);
else if (lerr & ERR_WARN)
ha_warning("Starting [%s:%d] for %s %s: %s\n",
listener->bind_conf->file, listener->bind_conf->line,
proxy_type_str(px), px->id, msg);
}
if (lerr & ERR_ABORT)
break;
}
if (err & ERR_ABORT)
break;
}
HA_SPIN_UNLOCK(PROTO_LOCK, &proto_lock);
return err;
}
/* unbinds all listeners of all registered protocols. They are also closed.
* This must be performed before calling exit() in order to get a chance to
* remove file-system based sockets and pipes.
* Returns a composition of ERR_NONE, ERR_RETRYABLE, ERR_FATAL, ERR_ABORT.
*/
int protocol_unbind_all(void)
{
struct protocol *proto;
struct listener *listener;
int err;
err = 0;
HA_SPIN_LOCK(PROTO_LOCK, &proto_lock);
list_for_each_entry(proto, &protocols, list) {
list_for_each_entry(listener, &proto->receivers, rx.proto_list)
unbind_listener(listener);
}
HA_SPIN_UNLOCK(PROTO_LOCK, &proto_lock);
return err;
}
/* stops all listeners of all registered protocols. This will normally catch
* every single listener, all protocols included. This is to be used during
* soft_stop() only. It does not return any error.
*/
void protocol_stop_now(void)
{
struct protocol *proto;
struct listener *listener, *lback;
HA_SPIN_LOCK(PROTO_LOCK, &proto_lock);
list_for_each_entry(proto, &protocols, list) {
list_for_each_entry_safe(listener, lback, &proto->receivers, rx.proto_list)
stop_listener(listener, 0, 1, 0);
}
HA_SPIN_UNLOCK(PROTO_LOCK, &proto_lock);
}
/* suspends all listeners of all registered protocols. This is typically
* used on SIG_TTOU to release all listening sockets for the time needed to
* try to bind a new process. The listeners enter LI_PAUSED or LI_ASSIGNED.
* It returns ERR_NONE, with ERR_FATAL on failure.
*/
int protocol_pause_all(void)
{
struct protocol *proto;
struct listener *listener;
int err;
err = 0;
HA_SPIN_LOCK(PROTO_LOCK, &proto_lock);
list_for_each_entry(proto, &protocols, list) {
list_for_each_entry(listener, &proto->receivers, rx.proto_list)
if (!suspend_listener(listener, 0, 0))
err |= ERR_FATAL;
}
HA_SPIN_UNLOCK(PROTO_LOCK, &proto_lock);
return err;
}
/* resumes all listeners of all registered protocols. This is typically used on
* SIG_TTIN to re-enable listening sockets after a new process failed to bind.
* The listeners switch to LI_READY/LI_FULL. It returns ERR_NONE, with ERR_FATAL
* on failure.
*/
int protocol_resume_all(void)
{
struct protocol *proto;
struct listener *listener;
int err;
err = 0;
HA_SPIN_LOCK(PROTO_LOCK, &proto_lock);
list_for_each_entry(proto, &protocols, list) {
list_for_each_entry(listener, &proto->receivers, rx.proto_list)
if (!resume_listener(listener, 0, 0))
err |= ERR_FATAL;
}
HA_SPIN_UNLOCK(PROTO_LOCK, &proto_lock);
return err;
}
/* enables all listeners of all registered protocols. This is intended to be
* used after a fork() to enable reading on all file descriptors. Returns
* composition of ERR_NONE.
*/
int protocol_enable_all(void)
{
struct protocol *proto;
struct listener *listener;
HA_SPIN_LOCK(PROTO_LOCK, &proto_lock);
list_for_each_entry(proto, &protocols, list) {
list_for_each_entry(listener, &proto->receivers, rx.proto_list)
enable_listener(listener);
}
HA_SPIN_UNLOCK(PROTO_LOCK, &proto_lock);
return ERR_NONE;
}
/*
* Local variables:
* c-indent-level: 8
* c-basic-offset: 8
* End:
*/