changeset 9052:2e51cf3ffd90 quic

QUIC: defer stream removal until all its data is acked. Previously, stream was kept alive until all its data is sent. This resulted in disabling retransmission of final part of stream when QUIC connection was closed right after closing stream connection.
author Roman Arutyunyan <arut@nginx.com>
date Mon, 22 Aug 2022 15:33:23 +0400
parents 37d5dddabaea
children 740d7d6e8ff0
files src/event/quic/ngx_event_quic.h src/event/quic/ngx_event_quic_ack.c src/event/quic/ngx_event_quic_streams.c
diffstat 3 files changed, 67 insertions(+), 26 deletions(-) [+]
line wrap: on
line diff
--- a/src/event/quic/ngx_event_quic.h	Tue Nov 29 17:46:46 2022 +0400
+++ b/src/event/quic/ngx_event_quic.h	Mon Aug 22 15:33:23 2022 +0400
@@ -85,6 +85,7 @@
     ngx_connection_t              *parent;
     ngx_connection_t              *connection;
     uint64_t                       id;
+    uint64_t                       sent;
     uint64_t                       acked;
     uint64_t                       send_max_data;
     uint64_t                       send_offset;
@@ -98,7 +99,8 @@
     ngx_quic_buffer_t              recv;
     ngx_quic_stream_send_state_e   send_state;
     ngx_quic_stream_recv_state_e   recv_state;
-    ngx_uint_t                     cancelable;  /* unsigned  cancelable:1; */
+    unsigned                       cancelable:1;
+    unsigned                       fin_acked:1;
 };
 
 
--- a/src/event/quic/ngx_event_quic_ack.c	Tue Nov 29 17:46:46 2022 +0400
+++ b/src/event/quic/ngx_event_quic_ack.c	Mon Aug 22 15:33:23 2022 +0400
@@ -253,6 +253,7 @@
                 break;
 
             case NGX_QUIC_FT_STREAM:
+            case NGX_QUIC_FT_RESET_STREAM:
                 ngx_quic_handle_stream_ack(c, f);
                 break;
             }
--- a/src/event/quic/ngx_event_quic_streams.c	Tue Nov 29 17:46:46 2022 +0400
+++ b/src/event/quic/ngx_event_quic_streams.c	Mon Aug 22 15:33:23 2022 +0400
@@ -887,7 +887,7 @@
 
     qs->send_state = NGX_QUIC_STREAM_SEND_SEND;
 
-    flow = qs->acked + qc->conf->stream_buffer_size - c->sent;
+    flow = qs->acked + qc->conf->stream_buffer_size - qs->sent;
 
     if (flow == 0) {
         wev->ready = 0;
@@ -900,13 +900,14 @@
 
     n = qs->send.size;
 
-    in = ngx_quic_write_buffer(pc, &qs->send, in, limit, c->sent);
+    in = ngx_quic_write_buffer(pc, &qs->send, in, limit, qs->sent);
     if (in == NGX_CHAIN_ERROR) {
         return NGX_CHAIN_ERROR;
     }
 
     n = qs->send.size - n;
     c->sent += n;
+    qs->sent += n;
     qc->streams.sent += n;
 
     if (flow == n) {
@@ -1045,9 +1046,12 @@
     if (!qc->closing) {
         /* make sure everything is sent and final size is received */
 
-        if (qs->recv_state == NGX_QUIC_STREAM_RECV_RECV
-            || qs->send_state == NGX_QUIC_STREAM_SEND_READY
-            || qs->send_state == NGX_QUIC_STREAM_SEND_SEND)
+        if (qs->recv_state == NGX_QUIC_STREAM_RECV_RECV) {
+            return NGX_OK;
+        }
+
+        if (qs->send_state != NGX_QUIC_STREAM_SEND_DATA_RECVD
+            && qs->send_state != NGX_QUIC_STREAM_SEND_RESET_RECVD)
         {
             return NGX_OK;
         }
@@ -1488,36 +1492,70 @@
 void
 ngx_quic_handle_stream_ack(ngx_connection_t *c, ngx_quic_frame_t *f)
 {
-    uint64_t                sent, unacked;
+    uint64_t                acked;
     ngx_quic_stream_t      *qs;
     ngx_quic_connection_t  *qc;
 
     qc = ngx_quic_get_connection(c);
 
-    qs = ngx_quic_find_stream(&qc->streams.tree, f->u.stream.stream_id);
-    if (qs == NULL) {
+    switch (f->type) {
+
+    case NGX_QUIC_FT_RESET_STREAM:
+
+        qs = ngx_quic_find_stream(&qc->streams.tree, f->u.reset_stream.id);
+        if (qs == NULL) {
+            return;
+        }
+
+        qs->send_state = NGX_QUIC_STREAM_SEND_RESET_RECVD;
+
+        ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0,
+                       "quic stream id:0x%xL ack reset final_size:%uL",
+                       qs->id, f->u.reset_stream.final_size);
+
+        break;
+
+    case NGX_QUIC_FT_STREAM:
+
+        qs = ngx_quic_find_stream(&qc->streams.tree, f->u.stream.stream_id);
+        if (qs == NULL) {
+            return;
+        }
+
+        acked = qs->acked;
+        qs->acked += f->u.stream.length;
+
+        if (f->u.stream.fin) {
+            qs->fin_acked = 1;
+        }
+
+        if (qs->send_state == NGX_QUIC_STREAM_SEND_DATA_SENT
+            && qs->acked == qs->sent && qs->fin_acked)
+        {
+            qs->send_state = NGX_QUIC_STREAM_SEND_DATA_RECVD;
+        }
+
+        ngx_log_debug4(NGX_LOG_DEBUG_EVENT, c->log, 0,
+                       "quic stream id:0x%xL ack len:%uL fin:%d unacked:%uL",
+                       qs->id, f->u.stream.length, f->u.stream.fin,
+                       qs->sent - qs->acked);
+
+        if (qs->connection
+            && qs->sent - acked == qc->conf->stream_buffer_size
+            && f->u.stream.length > 0)
+        {
+            ngx_quic_set_event(qs->connection->write);
+        }
+
+        break;
+
+    default:
         return;
     }
 
     if (qs->connection == NULL) {
-        qs->acked += f->u.stream.length;
-        return;
+        ngx_quic_close_stream(qs);
     }
-
-    sent = qs->connection->sent;
-    unacked = sent - qs->acked;
-    qs->acked += f->u.stream.length;
-
-    ngx_log_debug4(NGX_LOG_DEBUG_EVENT, c->log, 0,
-                   "quic stream id:0x%xL ack len:%uL acked:%uL unacked:%uL",
-                   qs->id, f->u.stream.length, qs->acked, sent - qs->acked);
-
-    if (unacked != qc->conf->stream_buffer_size) {
-        /* not blocked on buffer size */
-        return;
-    }
-
-    ngx_quic_set_event(qs->connection->write);
 }