cvs commit: src/sys/net if_ethersubr.c

[M. Warner Losh]

In message: <20061212.140133.1649770385.imp at bsdimp.com>
            "M. Warner Losh" <imp at bsdimp.com> writes:
: In message: <20061212183825.GF781 at funkthat.com>
:             John-Mark Gurney <gurney_j at resnet.uoregon.edu> writes:
: : Luigi Rizzo wrote this message on Tue, Dec 12, 2006 at 06:24 -0800:
: : > On Tue, Dec 12, 2006 at 03:17:59PM +0100, Bernd Walter wrote:
: : > > On Tue, Dec 12, 2006 at 05:57:56AM -0800, Luigi Rizzo wrote:
: : > ...
: : > > > then i suppose the proper fix is to revert to m_copy() and
: : > > > work on if_simloop() so that 1. it handles a readonly chain, and
: : > > > 2. when doing so, it passes up a properly aligned packet...
: : > > 
: : > > Can't comment on this, as I don't have enough knowledge about network
: : > > code.
: : > > According to the xscale report it was likely never properly aligned,
: : > > the alignment obviously just moved with your change.
: : > > 
: : > > > however note that there is already some code in net/if_loop.c::if_simloop(),
: : > > > just that it uses this:
: : > > > 
: : > > > 	#if defined(__ia64__) || defined(__sparc64__)
: : > ...
: : > > > to detect whether the architecture is alignment-sensitive.
: : > > > Is there any other identifier that we can use to check ?
: : > > 
: : > > I wonder how many of these are missing __arm__?
: : > 
: : > and this is why i wonder if there is a generic identifier
: : > that we can use to provide alignment.
: : 
: : How about?
: : #define __NO_STRICT_ALIGNMENT
: : 
: : It's already defined for amd64 and i386, so all you have to do it test
: : that it isn't defined...
: 
: __NO_STRICT_ALIGNMENT is relatively new.  Its definition in _types.h,
: while established practice in NetBSD, met with considerable
: controversy when I tried to expand it in FreeBSD land.  However,
: putting things in param.h met with no resistance whatsoever and was
: actively suggested.  Maybe we should move this straggler from _types.h
: to param.h and start using it more often.
: 
: Warner
: 

Here's what I came up with this afternoon between fires at work.

Comments?

Warner

http://perforce.freebsd.org/chv.cgi?CH=111579

Change 111579 by imp at imp_lighthouse on 2006/12/12 22:08:26

	Move __NO_STRICT_ALIGNMENT and use it.

Affected files ...

.. //depot/projects/arm/src/sys/amd64/include/_types.h#7 edit
.. //depot/projects/arm/src/sys/amd64/include/param.h#5 edit
.. //depot/projects/arm/src/sys/i386/include/_types.h#7 edit
.. //depot/projects/arm/src/sys/i386/include/param.h#4 edit
.. //depot/projects/arm/src/sys/net/bpf_filter.c#5 edit
.. //depot/projects/arm/src/sys/net/if_loop.c#8 edit

Differences ...

==== //depot/projects/arm/src/sys/amd64/include/_types.h#7 (text+ko) ====

@@ -43,8 +43,6 @@
 #error this file needs sys/cdefs.h as a prerequisite
 #endif
 
-#define __NO_STRICT_ALIGNMENT
-
 /*
  * Basic types upon which most other types are built.
  */

==== //depot/projects/arm/src/sys/amd64/include/param.h#5 (text+ko) ====

@@ -66,6 +66,7 @@
 
 #ifndef _NO_NAMESPACE_POLLUTION
 
+#define __NO_STRICT_ALIGNMENT
 #define __HAVE_ACPI
 #define __PCI_REROUTE_INTERRUPT
 

==== //depot/projects/arm/src/sys/i386/include/_types.h#7 (text+ko) ====

@@ -43,8 +43,6 @@
 #error this file needs sys/cdefs.h as a prerequisite
 #endif
 
-#define __NO_STRICT_ALIGNMENT
-
 /*
  * Basic types upon which most other types are built.
  */

==== //depot/projects/arm/src/sys/i386/include/param.h#4 (text+ko) ====

@@ -51,6 +51,7 @@
 
 #ifndef _NO_NAMESPACE_POLLUTION
 
+#define __NO_STRICT_ALIGNMENT
 #define __HAVE_ACPI
 #define __PCI_REROUTE_INTERRUPT
 

==== //depot/projects/arm/src/sys/net/bpf_filter.c#5 (text+ko) ====

@@ -38,11 +38,7 @@
 
 #include <sys/param.h>
 
-#ifdef sun
-#include <netinet/in.h>
-#endif
-
-#ifndef __i386__
+#ifndef __NO_STRICT_ALIGNMENT
 #define BPF_ALIGN
 #endif
 

==== //depot/projects/arm/src/sys/net/if_loop.c#8 (text+ko) ====

@@ -290,7 +290,7 @@
 	/* Strip away media header */
 	if (hlen > 0) {
 		m_adj(m, hlen);
-#if defined(__ia64__) || defined(__sparc64__)
+#ifndef __NO_STRICT_ALIGNMENT
 		/*
 		 * Some archs do not like unaligned data, so
 		 * we move data down in the first mbuf.