MEDIUM: backend: add reused conn to sess if mux marked as HOL blocking

If a connection is using a mux protocol subject to HOL blocking, add it
to the session instead of the available list to avoid sharing it with
other clients on connection reuse.

diff --git a/src/backend.c b/src/backend.c
index 48cc7a661a7f9dee4206aea7fdded78ac7ee7bfc..99f179d5d2c03d7acaed9528af8457cbdf42389e 100644 (file)
--- a/src/backend.c
+++ b/src/backend.c
@@ -1100,7 +1100,7 @@ static void assign_tproxy_address(struct stream *s)
  * (safe or idle connections). The <is_safe> argument means what type of
  * connection the caller wants.
  */
-static struct connection *conn_backend_get(struct server *srv, int is_safe)
+static struct connection *conn_backend_get(struct stream *s, struct server *srv, int is_safe)
 {
        struct mt_list *mt_list = is_safe ? srv->safe_conns : srv->idle_conns;
        struct connection *conn;
@@ -1202,7 +1202,16 @@ static struct connection *conn_backend_get(struct server *srv, int is_safe)
                conn->flags &= ~CO_FL_LIST_MASK;
                __ha_barrier_atomic_store();
 
-               LIST_ADDQ(&srv->available_conns[tid], mt_list_to_list(&conn->list));
+               if ((s->be->options & PR_O_REUSE_MASK) == PR_O_REUSE_SAFE &&
+                   conn->mux->flags & MX_FL_HOL_RISK) {
+                       /* attach the connection to the session private list
+                        */
+                       conn->owner = s->sess;
+                       session_add_conn(conn->owner, conn, conn->target);
+               }
+               else {
+                       LIST_ADDQ(&srv->available_conns[tid], mt_list_to_list(&conn->list));
+               }
        }
        return conn;
 }
@@ -1279,18 +1288,18 @@ int connect_server(struct stream *s)
                                /* we're on the second column of the tables above, let's
                                 * try idle then safe.
                                 */
-                               srv_conn = conn_backend_get(srv, 0);
+                               srv_conn = conn_backend_get(s, srv, 0);
                        }
                        else if (srv->safe_conns &&
                                 ((s->txn && (s->txn->flags & TX_NOT_FIRST)) ||
                                  (s->be->options & PR_O_REUSE_MASK) >= PR_O_REUSE_AGGR) &&
                                 srv->curr_safe_nb > 0) {
-                               srv_conn = conn_backend_get(srv, 1);
+                               srv_conn = conn_backend_get(s, srv, 1);
                        }
                        else if (srv->idle_conns &&
                                 ((s->be->options & PR_O_REUSE_MASK) == PR_O_REUSE_ALWS) &&
                                 srv->curr_idle_nb > 0) {
-                               srv_conn = conn_backend_get(srv, 0);
+                               srv_conn = conn_backend_get(s, srv, 0);
                        }
                        /* If we've picked a connection from the pool, we now have to
                         * detach it. We may have to get rid of the previous idle