BUG/MEDIUM: streams: Don't redispatch with L7 retries if redispatch isn't set.

Move the logic to decide if we redispatch to a new server from
sess_update_st_cer() to a new inline function, stream_choose_redispatch(), and
use it in do_l7_retry() instead of just setting the state to SI_ST_REQ.
That way, when using L7 retries, we won't redispatch the request to another
server except if "option redispatch" is used.

This should be backported to 2.0.

include/proto/stream.h

@@ -28,6 +28,8 @@
 #include <types/stream.h>
 #include <proto/fd.h>
 #include <proto/freq_ctr.h>
+#include <proto/obj_type.h>
+#include <proto/queue.h>
 #include <proto/stick_table.h>
 #include <proto/task.h>
 
@@ -351,6 +353,48 @@ static inline void stream_init_srv_conn(struct stream *sess)
 	LIST_INIT(&sess->by_srv);
 }
 
+static inline void stream_choose_redispatch(struct stream *s)
+{
+	struct stream_interface *si = &s->si[1];
+
+	/* If the "redispatch" option is set on the backend, we are allowed to
+	 * retry on another server. By default this redispatch occurs on the
+	 * last retry, but if configured we allow redispatches to occur on
+	 * configurable intervals, e.g. on every retry. In order to achieve this,
+	 * we must mark the stream unassigned, and eventually clear the DIRECT
+	 * bit to ignore any persistence cookie. We won't count a retry nor a
+	 * redispatch yet, because this will depend on what server is selected.
+	 * If the connection is not persistent, the balancing algorithm is not
+	 * determinist (round robin) and there is more than one active server,
+	 * we accept to perform an immediate redispatch without waiting since
+	 * we don't care about this particular server.
+	 */
+	if (objt_server(s->target) &&
+	    (s->be->options & PR_O_REDISP) && !(s->flags & SF_FORCE_PRST) &&
+	    ((__objt_server(s->target)->cur_state < SRV_ST_RUNNING) ||
+	     (((s->be->redispatch_after > 0) &&
+	       ((s->be->conn_retries - si->conn_retries) %
+	        s->be->redispatch_after == 0)) ||
+	      ((s->be->redispatch_after < 0) &&
+	       ((s->be->conn_retries - si->conn_retries) %
+	        (s->be->conn_retries + 1 + s->be->redispatch_after) == 0))) ||
+	     (!(s->flags & SF_DIRECT) && s->be->srv_act > 1 &&
+	      ((s->be->lbprm.algo & BE_LB_KIND) == BE_LB_KIND_RR)))) {
+		sess_change_server(s, NULL);
+		if (may_dequeue_tasks(objt_server(s->target), s->be))
+			process_srv_queue(objt_server(s->target));
+
+		s->flags &= ~(SF_DIRECT | SF_ASSIGNED | SF_ADDR_SET);
+		si->state = SI_ST_REQ;
+	} else {
+		if (objt_server(s->target))
+			_HA_ATOMIC_ADD(&__objt_server(s->target)->counters.retries, 1);
+		_HA_ATOMIC_ADD(&s->be->be_counters.retries, 1);
+		si->state = SI_ST_ASS;
+	}
+
+}
+
 void service_keywords_register(struct action_kw_list *kw_list);
 void list_services(FILE *out);
 

src/proto_htx.c

@@ -1406,13 +1406,13 @@ static __inline int do_l7_retry(struct stream *s, struct stream_interface *si)
 	res->flags &= ~(CF_READ_ERROR | CF_READ_TIMEOUT | CF_SHUTR | CF_EOI | CF_READ_NULL | CF_SHUTR_NOW);
 	res->analysers = 0;
 	si->flags &= ~(SI_FL_ERR | SI_FL_EXP | SI_FL_RXBLK_SHUT);
-	si->state = SI_ST_REQ;
+	stream_choose_redispatch(s);
 	si->exp = TICK_ETERNITY;
 	res->rex = TICK_ETERNITY;
 	res->to_forward = 0;
 	res->analyse_exp = TICK_ETERNITY;
 	res->total = 0;
-	s->flags &= ~(SF_ASSIGNED | SF_ADDR_SET | SF_ERR_SRVTO | SF_ERR_SRVCL);
+	s->flags &= ~(SF_ERR_SRVTO | SF_ERR_SRVCL);
 	si_release_endpoint(&s->si[1]);
 	b_free(&req->buf);
 	/* Swap the L7 buffer with the channel buffer */

src/stream.c

@@ -770,41 +770,7 @@ static void sess_update_st_cer(struct stream *s)
 		return;
 	}
 
-	/* If the "redispatch" option is set on the backend, we are allowed to
+	stream_choose_redispatch(s);
-	 * retry on another server. By default this redispatch occurs on the
-	 * last retry, but if configured we allow redispatches to occur on
-	 * configurable intervals, e.g. on every retry. In order to achieve this,
-	 * we must mark the stream unassigned, and eventually clear the DIRECT
-	 * bit to ignore any persistence cookie. We won't count a retry nor a
-	 * redispatch yet, because this will depend on what server is selected.
-	 * If the connection is not persistent, the balancing algorithm is not
-	 * determinist (round robin) and there is more than one active server,
-	 * we accept to perform an immediate redispatch without waiting since
-	 * we don't care about this particular server.
-	 */
-	if (objt_server(s->target) &&
-	    (s->be->options & PR_O_REDISP) && !(s->flags & SF_FORCE_PRST) &&
-	    ((__objt_server(s->target)->cur_state < SRV_ST_RUNNING) ||
-	     (((s->be->redispatch_after > 0) &&
-	       ((s->be->conn_retries - si->conn_retries) %
-	        s->be->redispatch_after == 0)) ||
-	      ((s->be->redispatch_after < 0) &&
-	       ((s->be->conn_retries - si->conn_retries) %
-	        (s->be->conn_retries + 1 + s->be->redispatch_after) == 0))) ||
-	     (!(s->flags & SF_DIRECT) && s->be->srv_act > 1 &&
-	      ((s->be->lbprm.algo & BE_LB_KIND) == BE_LB_KIND_RR)))) {
-		sess_change_server(s, NULL);
-		if (may_dequeue_tasks(objt_server(s->target), s->be))
-			process_srv_queue(objt_server(s->target));
-
-		s->flags &= ~(SF_DIRECT | SF_ASSIGNED | SF_ADDR_SET);
-		si->state = SI_ST_REQ;
-	} else {
-		if (objt_server(s->target))
-			_HA_ATOMIC_ADD(&__objt_server(s->target)->counters.retries, 1);
-		_HA_ATOMIC_ADD(&s->be->be_counters.retries, 1);
-		si->state = SI_ST_ASS;
-	}
 
 	if (si->flags & SI_FL_ERR) {
 		/* The error was an asynchronous connection error, and we will