From 83bcd693b084b044a988fffc9fa63edd856c9f10 Mon Sep 17 00:00:00 2001
From: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Date: Wed, 11 Dec 2019 19:40:36 -0500
Subject: [PATCH] lib/iscsi: Assert if PDU ref count goes negative

Error log had been collected if PDU ref count went negative. However,
error log is not easy to notice.  SPDK iSCSI target is more stable
than before and SPDK iSCSI task has such assert.  Hence replace
error log by assert for PDU.

Signed-off-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Change-Id: I28c4f5e29f0dfd72436b0131e09f9707822165fc
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/477630
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Changpeng Liu <changpeng.liu@intel.com>
---
 lib/iscsi/iscsi_subsystem.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/lib/iscsi/iscsi_subsystem.c b/lib/iscsi/iscsi_subsystem.c
index 4b77dae84..528e48fd3 100644
--- a/lib/iscsi/iscsi_subsystem.c
+++ b/lib/iscsi/iscsi_subsystem.c
@@ -294,13 +294,9 @@ void spdk_put_pdu(struct spdk_iscsi_pdu *pdu)
 		return;
 	}
 
+	assert(pdu->ref > 0);
 	pdu->ref--;
 
-	if (pdu->ref < 0) {
-		SPDK_ERRLOG("Negative PDU refcount: %p\n", pdu);
-		pdu->ref = 0;
-	}
-
 	if (pdu->ref == 0) {
 		if (pdu->mobj) {
 			spdk_mempool_put(pdu->mobj->mp, (void *)pdu->mobj);