From owner-svn-src-projects@FreeBSD.ORG  Mon Jun  1 09:43:58 2009
Return-Path: <owner-svn-src-projects@FreeBSD.ORG>
Delivered-To: svn-src-projects@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id EF11B106566C;
	Mon,  1 Jun 2009 09:43:58 +0000 (UTC)
	(envelope-from rwatson@FreeBSD.org)
Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:4f8:fff6::2c])
	by mx1.freebsd.org (Postfix) with ESMTP id DD7148FC17;
	Mon,  1 Jun 2009 09:43:58 +0000 (UTC)
	(envelope-from rwatson@FreeBSD.org)
Received: from svn.freebsd.org (localhost [127.0.0.1])
	by svn.freebsd.org (8.14.3/8.14.3) with ESMTP id n519hwNN071610;
	Mon, 1 Jun 2009 09:43:58 GMT (envelope-from rwatson@svn.freebsd.org)
Received: (from rwatson@localhost)
	by svn.freebsd.org (8.14.3/8.14.3/Submit) id n519hwH8071609;
	Mon, 1 Jun 2009 09:43:58 GMT (envelope-from rwatson@svn.freebsd.org)
Message-Id: <200906010943.n519hwH8071609@svn.freebsd.org>
From: Robert Watson <rwatson@FreeBSD.org>
Date: Mon, 1 Jun 2009 09:43:58 +0000 (UTC)
To: src-committers@freebsd.org, svn-src-projects@freebsd.org
X-SVN-Group: projects
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Cc: 
Subject: svn commit: r193215 - projects/pnet/sys/netinet
X-BeenThere: svn-src-projects@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: "SVN commit messages for the src &quot; projects&quot;
	tree" <svn-src-projects.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-projects>, 
	<mailto:svn-src-projects-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/svn-src-projects>
List-Post: <mailto:svn-src-projects@freebsd.org>
List-Help: <mailto:svn-src-projects-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-projects>, 
	<mailto:svn-src-projects-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Mon, 01 Jun 2009 09:43:59 -0000

Author: rwatson
Date: Mon Jun  1 09:43:58 2009
New Revision: 193215
URL: http://svn.freebsd.org/changeset/base/193215

Log:
  When cheaply calculating flow identifiers for packets coming in from
  network device drivers without hardware flow calculation, or for loopback
  traffic, use a different cheap hash that puts all interesting entropy
  into the bottom 8 bits of the flow ID, which works well with our default
  flow ID -> CPU mapping.

Modified:
  projects/pnet/sys/netinet/ip_input.c

Modified: projects/pnet/sys/netinet/ip_input.c
==============================================================================
--- projects/pnet/sys/netinet/ip_input.c	Mon Jun  1 09:32:12 2009	(r193214)
+++ projects/pnet/sys/netinet/ip_input.c	Mon Jun  1 09:43:58 2009	(r193215)
@@ -442,7 +442,10 @@ ip_input_m2flow(struct mbuf *m, uintptr_
 		goto bad;
 	}
 	m->m_flags |= M_FLOWID;
-	m->m_pkthdr.flowid = ip->ip_src.s_addr ^ ip->ip_dst.s_addr;
+	m->m_pkthdr.flowid = ((ip->ip_src.s_addr & 0xff000000) >> 24) ^
+	    ((ip->ip_src.s_addr & 0xff0000) >> 16) ^
+	    ((ip->ip_src.s_addr & 0xff00) >> 8) ^
+	    (ip->ip_src.s_addr & 0xff) ^ ip->ip_p;
 	return (m);
 
 bad: