MEDIUM: quic: Remove the QUIC connection reference counter
There is no need to use such a reference counter anymore since the QUIC
connections are always handled by the same thread.
quic_conn_drop() is removed. Its code is merged into quic_conn_release().
diff --git a/include/haproxy/xprt_quic-t.h b/include/haproxy/xprt_quic-t.h
index 37bfad4..4174924 100644
--- a/include/haproxy/xprt_quic-t.h
+++ b/include/haproxy/xprt_quic-t.h
@@ -661,13 +661,6 @@
#define QUIC_FL_ACCEPT_REGISTERED (1U << QUIC_FL_ACCEPT_REGISTERED_BIT)
#define QUIC_FL_CONN_IMMEDIATE_CLOSE (1U << 31)
struct quic_conn {
- /* The quic_conn instance is refcounted as it can be used by threads
- * outside of the connection pinned thread.
- *
- * By default it is initialized to 0.
- */
- uint refcount;
-
uint32_t version;
/* QUIC transport parameters TLS extension */
int tps_tls_ext;
diff --git a/src/xprt_quic.c b/src/xprt_quic.c
index 66b6e4f..bb35f70 100644
--- a/src/xprt_quic.c
+++ b/src/xprt_quic.c
@@ -3514,33 +3514,30 @@
return 0;
}
-/* Increment the <qc> refcount.
+/* Release the quic_conn <qc>. The connection is removed from the CIDs tree.
+ * The connection tasklet is killed.
*
- * This operation must be conducted when manipulating the quic_conn outside of
- * the connection pinned thread. These threads can only retrieve the connection
- * in the CID tree, so this function must be conducted under the CID lock.
+ * This function must only be called by the thread responsible of the quic_conn
+ * tasklet.
*/
-static inline void quic_conn_take(struct quic_conn *qc)
-{
- HA_ATOMIC_INC(&qc->refcount);
-}
-
-/* Decrement the <qc> refcount. If the refcount is zero *BEFORE* the
- * subtraction, the quic_conn is freed.
- */
-static void quic_conn_drop(struct quic_conn *qc)
+static void quic_conn_release(struct quic_conn *qc)
{
- struct ssl_sock_ctx *conn_ctx;
int i;
+ struct ssl_sock_ctx *conn_ctx;
- if (!qc)
- return;
+ if (qc->timer_task) {
+ task_destroy(qc->timer_task);
+ qc->timer_task = NULL;
+ }
- if (HA_ATOMIC_FETCH_SUB(&qc->refcount, 1))
- return;
+ /* remove the connection from receiver cids trees */
+ ebmb_delete(&qc->odcid_node);
+ ebmb_delete(&qc->scid_node);
+ free_quic_conn_cids(qc);
conn_ctx = HA_ATOMIC_LOAD(&qc->xprt_ctx);
if (conn_ctx) {
+ tasklet_free(conn_ctx->wait_event.tasklet);
SSL_free(conn_ctx->ssl);
pool_free(pool_head_quic_conn_ctx, conn_ctx);
}
@@ -3553,44 +3550,12 @@
TRACE_PROTO("QUIC conn. freed", QUIC_EV_CONN_FREED, qc);
}
-/* Release the quic_conn <qc>. It will decrement its refcount so that the
- * connection will be freed once all threads have finished to work with it. The
- * connection is removed from the CIDs tree and thus cannot be found by other
- * threads after it. The connection tasklet is killed.
- *
- * Do not use <qc> after it as it may be freed. This function must only be
- * called by the thread responsible of the quic_conn tasklet.
- */
-static void quic_conn_release(struct quic_conn *qc)
-{
- struct ssl_sock_ctx *conn_ctx;
-
- /* remove the connection from receiver cids trees */
- ebmb_delete(&qc->odcid_node);
- ebmb_delete(&qc->scid_node);
- free_quic_conn_cids(qc);
-
- /* Kill the tasklet. Do not use tasklet_free as this is not thread safe
- * as other threads may call tasklet_wakeup after this.
- */
- conn_ctx = HA_ATOMIC_LOAD(&qc->xprt_ctx);
- if (conn_ctx)
- tasklet_kill(conn_ctx->wait_event.tasklet);
-
- quic_conn_drop(qc);
-}
-
void quic_close(struct connection *conn, void *xprt_ctx)
{
struct ssl_sock_ctx *conn_ctx = xprt_ctx;
struct quic_conn *qc = conn_ctx->qc;
TRACE_ENTER(QUIC_EV_CONN_CLOSE, qc);
- /* This task must be deleted by the connection-pinned thread. */
- if (qc->timer_task) {
- task_destroy(qc->timer_task);
- qc->timer_task = NULL;
- }
/* Next application data can be dropped. */
qc->mux_state = QC_MUX_RELEASED;
@@ -3691,8 +3656,6 @@
goto err;
}
- HA_ATOMIC_STORE(&qc->refcount, 0);
-
buf_area = pool_alloc(pool_head_quic_conn_rxbuf);
if (!buf_area) {
TRACE_PROTO("Could not allocate a new RX buffer", QUIC_EV_CONN_INIT, qc);
@@ -3791,7 +3754,7 @@
pool_free(pool_head_quic_conn_rxbuf, buf_area);
if (qc)
qc->rx.buf.area = NULL;
- quic_conn_drop(qc);
+ quic_conn_release(qc);
return NULL;
}
@@ -4163,9 +4126,6 @@
found_in_dcid = 1;
end:
- if (qc)
- quic_conn_take(qc);
-
/* If found in DCIDs tree, remove the quic_conn from the ODCIDs tree.
* If already done, this is a noop.
*/
@@ -4506,14 +4466,12 @@
pkt->qc = qc;
}
- quic_conn_take(qc);
-
if (likely(!qc_to_purge)) {
/* Enqueue this packet. */
pkt->qc = qc;
}
else {
- quic_conn_drop(qc_to_purge);
+ quic_conn_release(qc_to_purge);
}
}
else {
@@ -4619,9 +4577,6 @@
TRACE_LEAVE(QUIC_EV_CONN_LPKT, qc ? qc : NULL, pkt);
- if (qc)
- quic_conn_drop(qc);
-
return pkt->len;
err:
@@ -4639,9 +4594,6 @@
TRACE_DEVEL("Leaving in error", QUIC_EV_CONN_LPKT,
qc ? qc : NULL, pkt);
- if (qc)
- quic_conn_drop(qc);
-
return -1;
}