[MEDIUM] added the necessary infrastructure to support per-server session limits : - the "maxconn" config option - the new SV_STCPEND state (connection pending) - a per-server pending connections queue
diff --git a/haproxy.c b/haproxy.c
index a87b341..d4953ac 100644
--- a/haproxy.c
+++ b/haproxy.c
@@ -86,6 +86,7 @@
#endif
#include "include/appsession.h"
+#include "include/mini-clist.h"
#ifndef HAPROXY_VERSION
#define HAPROXY_VERSION "1.2.12"
@@ -283,6 +284,7 @@
#define sizeof_task sizeof(struct task)
#define sizeof_session sizeof(struct session)
+#define sizeof_pendconn sizeof(struct pendconn)
#define sizeof_buffer sizeof(struct buffer)
#define sizeof_fdtab sizeof(struct fdtab)
#define sizeof_requri REQURI_LEN
@@ -406,12 +408,13 @@
/* different possible states for the server side */
#define SV_STIDLE 0
-#define SV_STCONN 1
-#define SV_STHEADERS 2
-#define SV_STDATA 3
-#define SV_STSHUTR 4
-#define SV_STSHUTW 5
-#define SV_STCLOSE 6
+#define SV_STCPEND 1
+#define SV_STCONN 2
+#define SV_STHEADERS 3
+#define SV_STDATA 4
+#define SV_STSHUTR 5
+#define SV_STSHUTW 6
+#define SV_STCLOSE 7
/* result of an I/O event */
#define RES_SILENT 0 /* didn't happen */
@@ -497,12 +500,20 @@
char data[BUFSIZE];
};
+struct pendconn {
+ struct list list; /* chaining ... */
+ struct session *sess; /* the session waiting for a connection */
+ struct server *srv; /* the server we are waiting for */
+};
+
struct server {
struct server *next;
int state; /* server state (SRV_*) */
int cklen; /* the len of the cookie, to speed up checks */
char *cookie; /* the id set in the cookie */
char *id; /* just for identification */
+ struct list pendconns; /* pending connections */
+ int nbpend; /* number of pending connections */
struct sockaddr_in addr; /* the address to connect to */
struct sockaddr_in source_addr; /* the address to which we want to bind for connect() */
short check_port; /* the port to use for the health checks */
@@ -515,6 +526,7 @@
unsigned int wscore; /* weight score, used during srv map computation */
int cur_sess; /* number of currently active sessions (including syn_sent) */
unsigned int cum_sess; /* cumulated number of sessions really sent to this server */
+ unsigned int maxconn; /* max # of active sessions. 0 = unlimited. */
struct proxy *proxy; /* the proxy this server belongs to */
};
@@ -551,6 +563,7 @@
struct sockaddr_storage cli_addr; /* the client address */
struct sockaddr_in srv_addr; /* the address to connect to */
struct server *srv; /* the server being used */
+ struct pendconn *pend_pos; /* if not NULL, points to the position in the pending queue */
char **req_cap; /* array of captured request headers (may be NULL) */
char **rsp_cap; /* array of captured response headers (may be NULL) */
struct {
@@ -690,6 +703,7 @@
int cfg_polling_mechanism = 0; /* POLL_USE_{SELECT|POLL|EPOLL} */
void **pool_session = NULL,
+ **pool_pendconn = NULL,
**pool_buffer = NULL,
**pool_fdtab = NULL,
**pool_requri = NULL,
@@ -854,7 +868,7 @@
/*********************************************************************/
#ifdef DEBUG_FULL
static char *cli_stnames[5] = {"HDR", "DAT", "SHR", "SHW", "CLS" };
-static char *srv_stnames[7] = {"IDL", "CON", "HDR", "DAT", "SHR", "SHW", "CLS" };
+static char *srv_stnames[8] = {"IDL", "PND", "CON", "HDR", "DAT", "SHR", "SHW", "CLS" };
#endif
/*********************************************************************/
@@ -1755,6 +1769,65 @@
/*********************************************************************/
+/* pending connections queues **************************************/
+/*********************************************************************/
+
+/*
+ * returns the first pending connection of server <s> or NULL if none.
+ */
+static inline struct pendconn *pendconn_peek(struct server *s) {
+ if (!s->nbpend)
+ return NULL;
+
+ return LIST_ELEM(s->pendconns.n, struct pendconn *, list);
+}
+
+/*
+ * Detaches pending connection <p>, decreases the pending count, and frees
+ * the pending connection.
+ */
+static inline void pendconn_free(struct pendconn *p) {
+ LIST_DEL(&p->list);
+ p->sess->pend_pos = NULL;
+ p->srv->nbpend--;
+ pool_free(pendconn, p);
+}
+
+/* detaches the first pending connection for server <s> and returns its
+ * associated session. If no pending connection is found, NULL is returned.
+ */
+static inline struct session *pendconn_get(struct server *s) {
+ struct pendconn *p;
+ struct session *sess;
+
+ p = pendconn_peek(s);
+ if (!p)
+ return NULL;
+ sess = p->sess;
+ pendconn_free(p);
+ return sess;
+}
+
+/* adds the session <sess> to the pending connection list of server <srv>.
+ * All counters and back pointers are updated accordingly. Returns NULL if
+ * no memory is available, otherwise the pendconn itself.
+ */
+static struct pendconn *pendconn_add(struct server *srv, struct session *sess) {
+ struct pendconn *p;
+
+ p = pool_alloc(pendconn);
+ if (!p)
+ return NULL;
+
+ LIST_ADDQ(&srv->pendconns, &p->list);
+ p->sess = sess;
+ p->srv = srv;
+ sess->pend_pos = p;
+ srv->nbpend++;
+ return p;
+}
+
+/*********************************************************************/
/* more specific functions ***************************************/
/*********************************************************************/
@@ -1780,6 +1853,8 @@
* frees the context associated to a session. It must have been removed first.
*/
static inline void session_free(struct session *s) {
+ if (s->pend_pos)
+ pendconn_free(s->pend_pos);
if (s->req)
pool_free(buffer, s->req);
if (s->rep)
@@ -7047,6 +7122,7 @@
curproxy->srv = newsrv;
newsrv->proxy = curproxy;
+ LIST_INIT(&newsrv->pendconns);
do_check = 0;
newsrv->state = SRV_RUNNING; /* early server setup */
newsrv->id = strdup(args[1]);
@@ -7118,6 +7194,10 @@
newsrv->uweight = w - 1;
cur_arg += 2;
}
+ else if (!strcmp(args[cur_arg], "maxconn")) {
+ newsrv->maxconn = atol(args[cur_arg + 1]);
+ cur_arg += 2;
+ }
else if (!strcmp(args[cur_arg], "check")) {
global.maxsock++;
do_check = 1;
@@ -8914,3 +8994,10 @@
return TBLCHKINT;
} /* end appsession_refresh */
+
+/*
+ * Local variables:
+ * c-indent-level: 4
+ * c-basic-offset: 4
+ * End:
+ */