MINOR: mux-quic: use send-list for STOP_SENDING/RESET_STREAM emission
When a STOP_SENDING or RESET_STREAM must be send, its corresponding qcs
is inserted into <qcc.send_list> via qcc_reset_stream() or
qcc_abort_stream_read().
This allows to remove the iteration on full qcs tree in qc_send().
Instead, STOP_SENDING and RESET_STREAM is done in the loop over
<qcc.send_list> as with STREAM frames. This should improve slightly the
performance, most notably when large number of streams are opened.
This must be backported up to 2.7.
diff --git a/src/mux_quic.c b/src/mux_quic.c
index bb30f58..195ba9f 100644
--- a/src/mux_quic.c
+++ b/src/mux_quic.c
@@ -818,6 +818,8 @@
TRACE_STATE("reset stream", QMUX_EV_QCS_END, qcc->conn, qcs);
qcs->flags |= QC_SF_TO_RESET;
qcs->err = err;
+
+ qcc_send_stream(qcs, 1);
tasklet_wakeup(qcc->wait_event.tasklet);
}
@@ -858,6 +860,8 @@
TRACE_STATE("abort stream read", QMUX_EV_QCS_END, qcc->conn, qcs);
qcs->flags |= (QC_SF_TO_STOP_SENDING|QC_SF_READ_ABORTED);
+
+ qcc_send_stream(qcs, 1);
tasklet_wakeup(qcc->wait_event.tasklet);
end:
@@ -1445,6 +1449,13 @@
return qcs->flags & QC_SF_FIN_STREAM && !b_data(&qcs->tx.buf);
}
+/* Return true if <qcs> has data to send in new STREAM frames. */
+static forceinline int qcs_need_sending(struct qcs *qcs)
+{
+ return b_data(&qcs->tx.buf) || qcs->tx.sent_offset < qcs->tx.offset ||
+ qcs_stream_fin(qcs);
+}
+
/* This function must be called by the upper layer to inform about the sending
* of a STREAM frame for <qcs> instance. The frame is of <data> length and on
* <offset>.
@@ -1713,7 +1724,6 @@
static int qc_send(struct qcc *qcc)
{
struct list frms = LIST_HEAD_INIT(frms);
- struct eb64_node *node;
struct qcs *qcs, *qcs_tmp;
int total = 0, tmp_total = 0;
@@ -1733,7 +1743,7 @@
}
if (qcc->flags & QC_CF_BLK_MFCTL)
- return 0;
+ goto err;
if (!(qcc->flags & QC_CF_APP_FINAL) && !eb_is_empty(&qcc->streams_by_id) &&
qcc->app_ops->finalize) {
@@ -1744,43 +1754,41 @@
qcc->flags |= QC_CF_APP_FINAL;
}
- /* Loop through all streams for STOP_SENDING/RESET_STREAM sending. Each
- * frame is send individually to guarantee emission.
- *
- * TODO Optimize sending by multiplexing several frames in one datagram.
- */
- node = eb64_first(&qcc->streams_by_id);
- while (node) {
- uint64_t id;
+ /* Send STREAM/STOP_SENDING/RESET_STREAM data for registered streams. */
+ list_for_each_entry_safe(qcs, qcs_tmp, &qcc->send_list, el_send) {
+ /* Stream must not be present in send_list if it has nothing to send. */
+ BUG_ON(!(qcs->flags & (QC_SF_TO_STOP_SENDING|QC_SF_TO_RESET)) &&
+ !qcs_need_sending(qcs));
- qcs = eb64_entry(node, struct qcs, by_id);
- id = qcs->id;
+ /* Each STOP_SENDING/RESET_STREAM frame is sent individually to
+ * guarantee its emission.
+ *
+ * TODO multiplex several frames in same datagram to optimize sending
+ */
+ if (qcs->flags & QC_SF_TO_STOP_SENDING) {
+ if (qcs_send_stop_sending(qcs))
+ goto out;
- if (quic_stream_is_uni(id) && quic_stream_is_remote(qcc, id)) {
- node = eb64_next(node);
- continue;
+ /* Remove stream from send_list if it had only STOP_SENDING
+ * to send.
+ */
+ if (!(qcs->flags & QC_SF_TO_RESET) && !qcs_need_sending(qcs)) {
+ LIST_DEL_INIT(&qcs->el_send);
+ continue;
+ }
}
- if (qcs->flags & QC_SF_TO_STOP_SENDING)
- qcs_send_stop_sending(qcs);
-
if (qcs->flags & QC_SF_TO_RESET) {
- qcs_send_reset(qcs);
- node = eb64_next(node);
- continue;
- }
-
- node = eb64_next(node);
- }
-
- /* Send STREAM data for registered streams. */
- list_for_each_entry(qcs, &qcc->send_list, el_send) {
- /* Stream must not be present in send_list if it has nothing to send. */
- BUG_ON(!b_data(&qcs->tx.buf) &&
- qcs->tx.sent_offset == qcs->tx.offset &&
- !qcs_stream_fin(qcs));
+ if (qcs_send_reset(qcs))
+ goto out;
- if (qcs_is_close_local(qcs)) {
+ /* RFC 9000 3.3. Permitted Frame Types
+ *
+ * A sender MUST NOT send
+ * a STREAM or STREAM_DATA_BLOCKED frame for a stream in the
+ * "Reset Sent" state or any terminal state -- that is, after
+ * sending a RESET_STREAM frame.
+ */
LIST_DEL_INIT(&qcs->el_send);
continue;
}