From: phk <phk@d4fa192b-c00b-0410-8231-f00ffab90ce4>
Date: Fri, 17 Oct 2008 21:29:49 +0000 (+0000)
Subject: ESI includes can hit the waiting list and since the state is stored
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=cdeb57416f476cd1291400e87830edf5dec5197b;p=varnish

ESI includes can hit the waiting list and since the state is stored
on the worker thread stack, we cannot just let another thread pick
up.

This is not as much a fix as a workaround: simply sleep until the
object we wait for is no longer busy.

The issue may have to be revisited in the long run, but for 2.0.x
this will have to do.

Fixes #345



git-svn-id: svn+ssh://projects.linpro.no/svn/varnish/trunk@3322 d4fa192b-c00b-0410-8231-f00ffab90ce4
---

diff --git a/varnish-cache/bin/varnishd/cache_hash.c b/varnish-cache/bin/varnishd/cache_hash.c
index ce6b7c0d..7ef852cb 100644
--- a/varnish-cache/bin/varnishd/cache_hash.c
+++ b/varnish-cache/bin/varnishd/cache_hash.c
@@ -266,7 +266,8 @@ HSH_Lookup(struct sess *sp)
 
 	if (busy_o != NULL) {
 		/* There are one or more busy objects, wait for them */
-		VTAILQ_INSERT_TAIL(&oh->waitinglist, sp, list);
+		if (sp->esis == 0)
+			VTAILQ_INSERT_TAIL(&oh->waitinglist, sp, list);
 		sp->objhead = oh;
 		UNLOCK(&oh->mtx);
 		return (NULL);
diff --git a/varnish-cache/bin/varnishd/cache_vrt_esi.c b/varnish-cache/bin/varnishd/cache_vrt_esi.c
index 8eb52aa3..c4975546 100644
--- a/varnish-cache/bin/varnishd/cache_vrt_esi.c
+++ b/varnish-cache/bin/varnishd/cache_vrt_esi.c
@@ -796,7 +796,6 @@ VRT_ESI(struct sess *sp)
 void
 ESI_Deliver(struct sess *sp)
 {
-
 	struct esi_bit *eb;
 	struct object *obj;
 
@@ -839,7 +838,16 @@ ESI_Deliver(struct sess *sp)
 		sp->step = STP_RECV;
 		http_ForceGet(sp->http);
 		http_Unset(sp->http, H_Content_Length);
-		CNT_Session(sp);
+		while (1) {
+			CNT_Session(sp);
+			if (sp->step == STP_DONE)
+				break;
+			AN(sp->wrk);
+			WSL_Flush(sp->wrk, 0);
+			DSL(0x20, SLT_Debug, sp->id, "loop waiting for ESI");
+			usleep(10000);
+		}
+		assert(sp->step == STP_DONE);
 		sp->esis--;
 		sp->obj = obj;
 
diff --git a/varnish-cache/bin/varnishtest/tests/r00345.vtc b/varnish-cache/bin/varnishtest/tests/r00345.vtc
new file mode 100644
index 00000000..b39030c5
--- /dev/null
+++ b/varnish-cache/bin/varnishtest/tests/r00345.vtc
@@ -0,0 +1,40 @@
+# $Id$
+
+test "#345, ESI waitinglist trouble"
+
+server s1 {
+	rxreq 
+	txresp -body {<esi:include src="someurl">}
+	rxreq 
+	sema r1 sync 2
+	delay 1
+	txresp -body {DATA}
+} -start
+
+varnish v1 -arg "-p diag_bitmap=0x20" -vcl+backend {
+	sub vcl_fetch {
+		if (req.url == "/") {
+			esi;
+		}
+	}
+} -start
+
+client c1 {
+	txreq
+	rxresp
+	expect resp.bodylen == 4
+} -start
+
+client c2 {
+	txreq
+	sema r1 sync 2
+	rxresp
+	expect resp.bodylen == 4
+} -run
+
+client c1 {
+	txreq
+	rxresp
+	expect resp.bodylen == 4
+} -run
+