Revert "MINOR: queue: factor out the proxy/server queuing code"

This reverts commit 3eecdb65c5a6b933399ebb0ac4ef86a7b97cf85d.

The recent changes since 5304669e1 MEDIUM: queue: make
pendconn_process_next_strm() only return the pendconn opened a tiny race
condition between stream_free() and process_srv_queue(), as the pendconn
is accessed outside of the lock, possibly while it's being freed. A
different approach is required.

diff --git a/src/queue.c b/src/queue.c
index 92089112233e81152851266deb55d7078f184faa..618825eaaae0c2702ee2edf713c60ac3259178ee 100644 (file)
--- a/src/queue.c
+++ b/src/queue.c
@@ -391,9 +391,6 @@ struct pendconn *pendconn_add(struct stream *strm)
        struct pendconn *p;
        struct proxy    *px;
        struct server   *srv;
-       struct queue    *q;
-       unsigned int *max_ptr;
-       unsigned int old_max, new_max;
 
        p = pool_alloc(pool_head_pendconn);
        if (!p)
@@ -414,26 +411,37 @@ struct pendconn *pendconn_add(struct stream *strm)
        strm->pend_pos = p;
 
        if (srv) {
-               q = &srv->queue;
-               max_ptr = &srv->counters.nbpend_max;
+               unsigned int old_max, new_max;
+
+               new_max = _HA_ATOMIC_ADD_FETCH(&srv->queue.length, 1);
+               old_max = srv->counters.nbpend_max;
+               while (new_max > old_max) {
+                       if (likely(_HA_ATOMIC_CAS(&srv->counters.nbpend_max, &old_max, new_max)))
+                               break;
+               }
+               __ha_barrier_atomic_store();
+
+               HA_SPIN_LOCK(QUEUE_LOCK, &p->srv->queue.lock);
+               p->queue_idx = srv->queue.idx - 1; // for increment
+               eb32_insert(&srv->queue.head, &p->node);
+               HA_SPIN_UNLOCK(QUEUE_LOCK, &p->srv->queue.lock);
        }
        else {
-               q = &px->queue;
-               max_ptr = &px->be_counters.nbpend_max;
-       }
+               unsigned int old_max, new_max;
 
-       new_max = _HA_ATOMIC_ADD_FETCH(&q->length, 1);
-       old_max = _HA_ATOMIC_LOAD(max_ptr);
-       while (new_max > old_max) {
-               if (likely(_HA_ATOMIC_CAS(max_ptr, &old_max, new_max)))
-                       break;
-       }
-       __ha_barrier_atomic_store();
+               new_max = _HA_ATOMIC_ADD_FETCH(&px->queue.length, 1);
+               old_max = px->be_counters.nbpend_max;
+               while (new_max > old_max) {
+                       if (likely(_HA_ATOMIC_CAS(&px->be_counters.nbpend_max, &old_max, new_max)))
+                               break;
+               }
+               __ha_barrier_atomic_store();
 
-       HA_SPIN_LOCK(QUEUE_LOCK, &q->lock);
-       p->queue_idx = q->idx - 1; // for increment
-       eb32_insert(&q->head, &p->node);
-       HA_SPIN_UNLOCK(QUEUE_LOCK, &q->lock);
+               HA_SPIN_LOCK(QUEUE_LOCK, &p->px->queue.lock);
+               p->queue_idx = px->queue.idx - 1; // for increment
+               eb32_insert(&px->queue.head, &p->node);
+               HA_SPIN_UNLOCK(QUEUE_LOCK, &p->px->queue.lock);
+       }
 
        _HA_ATOMIC_INC(&px->totpend);
        return p;