[master] 5ecbde381 Make a special case for sending h2 RST frames

[Dridi Boukelmoune]

commit 5ecbde3812f9d17b47faf3b6c44567bcb7060fac
Author: Dridi Boukelmoune <dridi.boukelmoune at gmail.com>
Date:   Fri Apr 19 11:48:43 2019 +0200

    Make a special case for sending h2 RST frames

diff --git a/bin/varnishd/http2/cache_http2.h b/bin/varnishd/http2/cache_http2.h
index 83bf5460c..44bd91783 100644
--- a/bin/varnishd/http2/cache_http2.h
+++ b/bin/varnishd/http2/cache_http2.h
@@ -223,6 +223,9 @@ void H2_Send_Frame(struct worker *, struct h2_sess *,
     h2_frame type, uint8_t flags, uint32_t len, uint32_t stream,
     const void *);
 
+void H2_Send_RST(struct worker *wrk, struct h2_sess *h2, struct h2_req *r2,
+    uint32_t stream, h2_error h2e);
+
 void H2_Send(struct worker *, struct h2_req *, h2_frame type, uint8_t flags,
     uint32_t len, const void *, uint64_t *acct);
 
diff --git a/bin/varnishd/http2/cache_http2_proto.c b/bin/varnishd/http2/cache_http2_proto.c
index 68c52e54f..577f777c2 100644
--- a/bin/varnishd/http2/cache_http2_proto.c
+++ b/bin/varnishd/http2/cache_http2_proto.c
@@ -1,5 +1,5 @@
 /*-
- * Copyright (c) 2016 Varnish Software AS
+ * Copyright (c) 2016-2019 Varnish Software AS
  * All rights reserved.
  *
  * Author: Poul-Henning Kamp <phk at phk.freebsd.dk>
@@ -132,28 +132,6 @@ h2_connectionerror(uint32_t u)
 
 /**********************************************************************/
 
-static void
-h2_tx_rst(struct worker *wrk, struct h2_sess *h2, struct h2_req *r2,
-    uint32_t stream, h2_error h2e)
-{
-	char b[4];
-
-	CHECK_OBJ_NOTNULL(h2, H2_SESS_MAGIC);
-	CHECK_OBJ_NOTNULL(r2, H2_REQ_MAGIC);
-
-	Lck_Lock(&h2->sess->mtx);
-	VSLb(h2->vsl, SLT_Debug, "H2: stream %u: %s", stream, h2e->txt);
-	Lck_Unlock(&h2->sess->mtx);
-	vbe32enc(b, h2e->val);
-
-	H2_Send_Get(wrk, h2, r2);
-	H2_Send_Frame(wrk, h2, H2_F_RST_STREAM, 0, sizeof b, stream, b);
-	H2_Send_Rel(h2, r2);
-}
-
-/**********************************************************************
- */
-
 struct h2_req *
 h2_new_req(const struct worker *wrk, struct h2_sess *h2,
     unsigned stream, struct req *req)
@@ -875,8 +853,10 @@ h2_vfp_body_fini(struct vfp_ctx *vc, struct vfp_entry *vfe)
 
 	if (vc->failed) {
 		CHECK_OBJ_NOTNULL(r2->req->wrk, WORKER_MAGIC);
-		h2_tx_rst(r2->req->wrk, h2, r2, r2->stream,
+		H2_Send_Get(r2->req->wrk, h2, r2);
+		H2_Send_RST(r2->req->wrk, h2, r2, r2->stream,
 		    H2SE_REFUSED_STREAM);
+		H2_Send_Rel(h2, r2);
 		Lck_Lock(&h2->sess->mtx);
 		r2->error = H2SE_REFUSED_STREAM;
 		if (h2->mailcall == r2) {
@@ -980,7 +960,9 @@ h2_procframe(struct worker *wrk, struct h2_sess *h2, h2_frame h2f)
 	if (h2->rxf_stream == 0 || h2e->connection)
 		return (h2e);	// Connection errors one level up
 
-	h2_tx_rst(wrk, h2, h2->req0, h2->rxf_stream, h2e);
+	H2_Send_Get(wrk, h2, h2->req0);
+	H2_Send_RST(wrk, h2, h2->req0, h2->rxf_stream, h2e);
+	H2_Send_Rel(h2, h2->req0);
 	return (0);
 }
 
@@ -1041,8 +1023,10 @@ h2_sweep(struct worker *wrk, struct h2_sess *h2)
 			break;
 		case H2_S_CLOS_REM:
 			if (!r2->scheduled) {
-				h2_tx_rst(wrk, h2, h2->req0, r2->stream,
+				H2_Send_Get(wrk, h2, h2->req0);
+				H2_Send_RST(wrk, h2, h2->req0, r2->stream,
 				    H2SE_REFUSED_STREAM);
+				H2_Send_Rel(h2, h2->req0);
 				h2_del_req(wrk, r2);
 				continue;
 			}
diff --git a/bin/varnishd/http2/cache_http2_send.c b/bin/varnishd/http2/cache_http2_send.c
index d1c3573ef..a778b35ea 100644
--- a/bin/varnishd/http2/cache_http2_send.c
+++ b/bin/varnishd/http2/cache_http2_send.c
@@ -113,7 +113,7 @@ h2_mk_hdr(uint8_t *hdr, h2_frame ftyp, uint8_t flags,
 }
 
 /*
- * This is the "raw" frame sender, all per stream accounting and
+ * This is the "raw" frame sender, all per-stream accounting and
  * prioritization must have happened before this is called, and
  * the session mtx must be held.
  */
@@ -349,6 +349,24 @@ h2_send(struct worker *wrk, struct h2_req *r2, h2_frame ftyp, uint8_t flags,
 	}
 }
 
+void
+H2_Send_RST(struct worker *wrk, struct h2_sess *h2, struct h2_req *r2,
+    uint32_t stream, h2_error h2e)
+{
+	char b[4];
+
+	CHECK_OBJ_NOTNULL(h2, H2_SESS_MAGIC);
+	CHECK_OBJ_NOTNULL(r2, H2_REQ_MAGIC);
+	AN(H2_SEND_HELD(h2, r2));
+
+	Lck_Lock(&h2->sess->mtx);
+	VSLb(h2->vsl, SLT_Debug, "H2: stream %u: %s", stream, h2e->txt);
+	Lck_Unlock(&h2->sess->mtx);
+	vbe32enc(b, h2e->val);
+
+	H2_Send_Frame(wrk, h2, H2_F_RST_STREAM, 0, sizeof b, stream, b);
+}
+
 void
 H2_Send(struct worker *wrk, struct h2_req *r2, h2_frame ftyp, uint8_t flags,
     uint32_t len, const void *ptr, uint64_t *counter)