Sat May 2 18:18:44 2009 UTC ()

Patch from Brian Marcotte on port-xen@:
write a "feature-rx-notify" to the xenstore, which is used by recent
linux dom0 kernels. This reduce packet loss when using a NetBSD domU
on such linux dom0.
This entry is ignored by NetBSD and older linux domUs.


(bouyer)

diff -r1.35 -r1.36 src/sys/arch/xen/xen/if_xennet_xenbus.c

--- src/sys/arch/xen/xen/if_xennet_xenbus.c 2009/04/29 22:21:49	1.35
+++ src/sys/arch/xen/xen/if_xennet_xenbus.c 2009/05/02 18:18:44	1.36

 @@ -1,14 +1,14 @@
-/*      $NetBSD: if_xennet_xenbus.c,v 1.35 2009/04/29 22:21:49 jym Exp $      */
+/*      $NetBSD: if_xennet_xenbus.c,v 1.36 2009/05/02 18:18:44 bouyer Exp $      */
 /*
  * Copyright (c) 2006 Manuel Bouyer.
+ *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  * 3. All advertising materials mentioning features or use of this software
 @@ -85,27 +85,27 @@
  * Purpose is to process the packets received from the outside. RX buffers
  * are pre-allocated through xennet_alloc_rx_buffer(), during xennet autoconf
  * attach. During pre-allocation, frontend pushes requests in the I/O ring, in
  * preparation for incoming packets from backend.
  * When RX packets need to be processed, backend takes the requests previously
  * offered by frontend and pushes the associated responses inside the I/O ring.
  * When done, it notifies frontend through an event notification, which will
  * asynchronously call xennet_handler() in frontend.
  * xennet_handler() processes the responses, generates the associated mbuf, and
  * passes it to the MI layer for further processing.
  */
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_xennet_xenbus.c,v 1.35 2009/04/29 22:21:49 jym Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_xennet_xenbus.c,v 1.36 2009/05/02 18:18:44 bouyer Exp $");
 #include "opt_xen.h"
 #include "opt_nfs_boot.h"
 #include "rnd.h"
 #include "bpfilter.h"
 #include <sys/param.h>
 #include <sys/device.h>
 #include <sys/conf.h>
 #include <sys/kernel.h>
 #include <sys/proc.h>
 #include <sys/systm.h>
 #include <sys/intr.h>
 @@ -492,26 +492,32 @@ again:
 	error = xenbus_printf(xbt, sc->sc_xbusd->xbusd_path,
 	    "tx-ring-ref","%u", sc->sc_tx_ring_gntref);
 	if (error) {
 		errmsg = "writing tx ring-ref";
 		goto abort_transaction;
+	}
 	error = xenbus_printf(xbt, sc->sc_xbusd->xbusd_path,
 	    "rx-ring-ref","%u", sc->sc_rx_ring_gntref);
 	if (error) {
 		errmsg = "writing rx ring-ref";
 		goto abort_transaction;
+	}
 	error = xenbus_printf(xbt, sc->sc_xbusd->xbusd_path,
 	    "feature-rx-notify", "%u", 1);
 	if (error) {
 		errmsg = "writing feature-rx-notify";
 		goto abort_transaction;
+	}
 	error = xenbus_printf(xbt, sc->sc_xbusd->xbusd_path,
 	    "event-channel", "%u", sc->sc_evtchn);
 	if (error) {
 		errmsg = "writing event channel";
 		goto abort_transaction;
+	}
 	error = xenbus_printf(xbt, sc->sc_xbusd->xbusd_path,
 	    "state", "%d", XenbusStateConnected);
 	if (error) {
 		errmsg = "writing frontend XenbusStateConnected";
 		goto abort_transaction;
+	}
 	error = xenbus_transaction_end(xbt, 0);
 	if (error == EAGAIN)