[master] 350e158d8 Retire the MAIN.sess_drop VSC

[Dridi Boukelmoune]

commit 350e158d86453356c4519ad67bf60e69e8fc9505
Author: Dridi Boukelmoune <dridi.boukelmoune at gmail.com>
Date:   Fri Sep 27 12:21:51 2019 +0200

    Retire the MAIN.sess_drop VSC
    
    When de16dba24abf landed its documentation was mixed up with the other
    sess_dropped counter. When sess_dropped appeared in ac393c4b825a the
    sess_drop counter was still function, it died short after as a side
    effect of ac2e067b0dac.

diff --git a/bin/varnishd/VSC_main.vsc b/bin/varnishd/VSC_main.vsc
index 0377f9659..ca5704267 100644
--- a/bin/varnishd/VSC_main.vsc
+++ b/bin/varnishd/VSC_main.vsc
@@ -27,12 +27,6 @@
 
 	Count of sessions successfully accepted
 
-.. varnish_vsc:: sess_drop
-	:group: wrk
-	:oneliner:	Sessions dropped
-
-	Count of sessions silently dropped due to lack of worker thread.
-
 .. varnish_vsc:: sess_fail
 	:group: wrk
 	:oneliner:	Session accept failures
diff --git a/bin/varnishd/cache/cache_acceptor.c b/bin/varnishd/cache/cache_acceptor.c
index 3336fd89f..68e61524e 100644
--- a/bin/varnishd/cache/cache_acceptor.c
+++ b/bin/varnishd/cache/cache_acceptor.c
@@ -373,19 +373,6 @@ vca_make_session(struct worker *wrk, void *arg)
 	/* Turn accepted socket into a session */
 	AN(wrk->aws->r);
 	sp = SES_New(wrk->pool);
-	if (sp == NULL) {
-		/*
-		 * We consider this a DoS situation and silently close the
-		 * connection with minimum effort and fuzz, rather than try
-		 * to send an intelligent message back.
-		 */
-		vca_pace_bad();
-		VTCP_nonblocking(wa->acceptsock);
-		closefd(&wa->acceptsock);
-		wrk->stats->sess_drop++;
-		WS_Release(wrk->aws, 0);
-		return;
-	}
 	CHECK_OBJ_NOTNULL(sp, SESS_MAGIC);
 	wrk->stats->s_sess++;
 
diff --git a/bin/varnishd/cache/cache_session.c b/bin/varnishd/cache/cache_session.c
index 875129f68..647b43665 100644
--- a/bin/varnishd/cache/cache_session.c
+++ b/bin/varnishd/cache/cache_session.c
@@ -365,7 +365,8 @@ SES_New(struct pool *pp)
 
 	CHECK_OBJ_NOTNULL(pp, POOL_MAGIC);
 	sp = MPL_Get(pp->mpl_sess, &sz);
-	sp->magic = SESS_MAGIC;
+	AN(sp);
+	INIT_OBJ(sp, SESS_MAGIC);
 	sp->pool = pp;
 	sp->refcnt = 1;
 	memset(sp->sattr, 0xff, sizeof sp->sattr);
diff --git a/bin/varnishtest/tests/t02011.vtc b/bin/varnishtest/tests/t02011.vtc
index 9c2269e74..45ec730c6 100644
--- a/bin/varnishtest/tests/t02011.vtc
+++ b/bin/varnishtest/tests/t02011.vtc
@@ -72,7 +72,6 @@ client c1 {
 varnish v1 -cliok "param.set thread_pool_min 3"
 delay 1
 varnish v1 -vsl_catchup
-varnish v1 -expect sess_drop == 0
 varnish v1 -expect sess_dropped == 0
 varnish v1 -expect req_dropped == 1
 varnish v1 -expect MEMPOOL.req0.live == 0
diff --git a/doc/changes.rst b/doc/changes.rst
index ac1b47902..06ebc0630 100644
--- a/doc/changes.rst
+++ b/doc/changes.rst
@@ -30,7 +30,7 @@ release process.
 NEXT (2020-03-15)
 ================================
 
-(nothing yet)
+* The ``MAIN.sess_drop`` counter is gone.
 
 ================================
 Varnish Cache 6.3.0 (2019-09-15)