From owner-svn-src-stable-7@FreeBSD.ORG  Tue Apr  7 18:14:02 2015
Return-Path: <owner-svn-src-stable-7@FreeBSD.ORG>
Delivered-To: svn-src-stable-7@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115])
 (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits))
 (No client certificate requested)
 by hub.freebsd.org (Postfix) with ESMTPS id 62CC6556;
 Tue,  7 Apr 2015 18:14:02 +0000 (UTC)
Received: from svn.freebsd.org (svn.freebsd.org
 [IPv6:2001:1900:2254:2068::e6a:0])
 (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits))
 (Client did not present a certificate)
 by mx1.freebsd.org (Postfix) with ESMTPS id 4CF01D43;
 Tue,  7 Apr 2015 18:14:02 +0000 (UTC)
Received: from svn.freebsd.org ([127.0.1.70])
 by svn.freebsd.org (8.14.9/8.14.9) with ESMTP id t37IE2w7069677;
 Tue, 7 Apr 2015 18:14:02 GMT (envelope-from davidcs@FreeBSD.org)
Received: (from davidcs@localhost)
 by svn.freebsd.org (8.14.9/8.14.9/Submit) id t37IE2qb069676;
 Tue, 7 Apr 2015 18:14:02 GMT (envelope-from davidcs@FreeBSD.org)
Message-Id: <201504071814.t37IE2qb069676@svn.freebsd.org>
X-Authentication-Warning: svn.freebsd.org: davidcs set sender to
 davidcs@FreeBSD.org using -f
From: David C Somayajulu <davidcs@FreeBSD.org>
Date: Tue, 7 Apr 2015 18:14:02 +0000 (UTC)
To: src-committers@freebsd.org, svn-src-all@freebsd.org,
 svn-src-stable@freebsd.org, svn-src-stable-7@freebsd.org
Subject: svn commit: r281219 - stable/7/sys/dev/bxe
X-SVN-Group: stable-7
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
X-BeenThere: svn-src-stable-7@freebsd.org
X-Mailman-Version: 2.1.18-1
Precedence: list
List-Id: SVN commit messages for only the 7-stable src tree
 <svn-src-stable-7.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/options/svn-src-stable-7>, 
 <mailto:svn-src-stable-7-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/svn-src-stable-7/>
List-Post: <mailto:svn-src-stable-7@freebsd.org>
List-Help: <mailto:svn-src-stable-7-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-stable-7>, 
 <mailto:svn-src-stable-7-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Tue, 07 Apr 2015 18:14:02 -0000

Author: davidcs
Date: Tue Apr  7 18:14:01 2015
New Revision: 281219
URL: https://svnweb.freebsd.org/changeset/base/281219

Log:
  MFC r281006
  When an mbuf allocation fails in the receive path, the mbuf containing the received packet is not sent to the host network stack and is reused again on the receive ring.  Remaining received packets in the ring are not processed in that invocation of bxe_rxeof() and defered to the task thread

Modified:
  stable/7/sys/dev/bxe/bxe.c
Directory Properties:
  stable/7/sys/   (props changed)

Modified: stable/7/sys/dev/bxe/bxe.c
==============================================================================
--- stable/7/sys/dev/bxe/bxe.c	Tue Apr  7 18:10:58 2015	(r281218)
+++ stable/7/sys/dev/bxe/bxe.c	Tue Apr  7 18:14:01 2015	(r281219)
@@ -3257,7 +3257,7 @@ bxe_rxeof(struct bxe_softc    *sc,
     uint16_t bd_cons, bd_prod, bd_prod_fw, comp_ring_cons;
     uint16_t hw_cq_cons, sw_cq_cons, sw_cq_prod;
     int rx_pkts = 0;
-    int rc;
+    int rc = 0;
 
     BXE_FP_RX_LOCK(fp);
 
@@ -3399,6 +3399,10 @@ bxe_rxeof(struct bxe_softc    *sc,
                                   (sc->max_rx_bufs != RX_BD_USABLE) ?
                                       bd_prod : bd_cons);
         if (rc != 0) {
+
+            /* we simply reuse the received mbuf and don't post it to the stack */
+            m = NULL;
+
             BLOGE(sc, "mbuf alloc fail for fp[%02d] rx chain (%d)\n",
                   fp->index, rc);
             fp->eth_q_stats.rx_soft_errors++;
@@ -3487,6 +3491,9 @@ next_cqe:
         sw_cq_cons = RCQ_NEXT(sw_cq_cons);
 
         /* limit spinning on the queue */
+        if (rc != 0)
+            break;
+
         if (rx_pkts == sc->rx_budget) {
             fp->eth_q_stats.rx_budget_reached++;
             break;