MEDIUM: mux-quic: respect peer connection data limit
This commit is similar to the previous one, but this time on the
connection level instead of the stream.
When the connection limit is reached, the connection is flagged with
QC_CF_BLK_MFCTL. This flag is checked in qc_send.
qcs_push_frame uses a new parameter which is used to not exceed the
connection flow-limit while calling it repeatdly over multiple streams
instance before transfering data to the transport layer.
diff --git a/include/haproxy/mux_quic-t.h b/include/haproxy/mux_quic-t.h
index c3aac18..b15b884 100644
--- a/include/haproxy/mux_quic-t.h
+++ b/include/haproxy/mux_quic-t.h
@@ -22,7 +22,8 @@
QCS_MAX_TYPES
};
-#define QC_CF_CC_RECV 0x00000001
+#define QC_CF_CC_RECV 0x00000001
+#define QC_CF_BLK_MFCTL 0x00000002 /* sending blocked due to connection flow-control */
struct qcc {
struct connection *conn;
@@ -51,6 +52,7 @@
/* flow-control fields set by the peer which we must respect. */
struct {
+ uint64_t md; /* connection flow control limit updated on MAX_DATA frames reception */
uint64_t msd_bidi_l; /* initial max-stream-data for peer local streams */
uint64_t msd_bidi_r; /* initial max-stream-data for peer remote streams */
} rfctl;
@@ -59,7 +61,7 @@
uint64_t max_data; /* Maximum number of bytes which may be received */
} rx;
struct {
- uint64_t max_data; /* Maximum number of bytes which may be sent */
+ uint64_t sent_offsets; /* sum of all offset sent */
} tx;
struct eb_root streams_by_id; /* all active streams by their ID */
diff --git a/src/mux_quic.c b/src/mux_quic.c
index eda6347..7a8ccfa 100644
--- a/src/mux_quic.c
+++ b/src/mux_quic.c
@@ -361,14 +361,18 @@
* buffer. The frame is then pushed to <frm_list>. If <fin> is set, and the
* <payload> buf is emptied after transfer, FIN bit is set on the STREAM frame.
* Transfer is automatically adjusted to not exceed the stream flow-control
- * limit.
+ * limit. <max_data> must contains the current sum offsets for the connection.
+ * This is useful to not exceed the connection flow-control limit when using
+ * repeatdly this function on multiple streams before passing the data to the
+ * lower layer.
*
* Returns the total bytes of newly transferred data or a negative error code.
*/
static int qcs_push_frame(struct qcs *qcs, struct buffer *out,
struct buffer *payload, int fin,
- struct list *frm_list)
+ struct list *frm_list, uint64_t max_data)
{
+ struct qcc *qcc = qcs->qcc;
struct quic_frame *frm;
int head, left, to_xfer;
int total = 0;
@@ -403,6 +407,11 @@
if (qcs->tx.offset + to_xfer > qcs->tx.msd)
to_xfer = qcs->tx.msd - qcs->tx.offset;
+ BUG_ON_HOT(max_data > qcc->rfctl.md);
+ /* do not overcome flow control limit on connection */
+ if (max_data + to_xfer > qcc->rfctl.md)
+ to_xfer = qcc->rfctl.md - max_data;
+
if (!left && !to_xfer)
goto out;
@@ -449,7 +458,8 @@
*/
void qcc_streams_sent_done(struct qcs *qcs, uint64_t data, uint64_t offset)
{
- uint64_t diff = data;
+ struct qcc *qcc = qcs->qcc;
+ uint64_t diff;
BUG_ON(offset > qcs->tx.sent_offset);
@@ -461,6 +471,12 @@
diff = offset + data - qcs->tx.sent_offset;
+ /* increase offset sum on connection */
+ qcc->tx.sent_offsets += diff;
+ BUG_ON_HOT(qcc->tx.sent_offsets > qcc->rfctl.md);
+ if (qcc->tx.sent_offsets == qcc->rfctl.md)
+ qcc->flags |= QC_CF_BLK_MFCTL;
+
/* increase offset on stream */
qcs->tx.sent_offset += diff;
BUG_ON_HOT(qcs->tx.sent_offset > qcs->tx.msd);
@@ -549,6 +565,9 @@
fprintf(stderr, "%s\n", __func__);
+ if (qcc->flags & QC_CF_BLK_MFCTL)
+ return 0;
+
/* loop through all streams, construct STREAM frames if data available.
* TODO optimize the loop to favor streams which are not too heavy.
*/
@@ -577,7 +596,8 @@
int ret;
char fin = qcs->flags & QC_SF_FIN_STREAM;
- ret = qcs_push_frame(qcs, out, buf, fin, &frms);
+ ret = qcs_push_frame(qcs, out, buf, fin, &frms,
+ qcc->tx.sent_offsets + total);
BUG_ON(ret < 0); /* TODO handle this properly */
if (ret > 0) {
@@ -742,7 +762,7 @@
lparams = &conn->qc->rx.params;
qcc->rx.max_data = lparams->initial_max_data;
- qcc->tx.max_data = 0;
+ qcc->tx.sent_offsets = 0;
/* Client initiated streams must respect the server flow control. */
qcc->strms[QCS_CLT_BIDI].max_streams = lparams->initial_max_streams_bidi;
@@ -774,6 +794,7 @@
qcc->lfctl.cl_bidi_r = 0;
rparams = &conn->qc->tx.params;
+ qcc->rfctl.md = rparams->initial_max_data;
qcc->rfctl.msd_bidi_l = rparams->initial_max_stream_data_bidi_local;
qcc->rfctl.msd_bidi_r = rparams->initial_max_stream_data_bidi_remote;