Module Name: src
Committed By: riastradh
Date: Sat Feb 25 00:34:25 UTC 2023
Modified Files:
src/sys/arch/xen/xen: xennetback_xenbus.c
Log Message:
xennetback(4): Fix membars in xennetback_rx_copy_process.
- No need for barrier around touching req_cons and rsp_prod_pvt,
which are private.
- RING_PUSH_RESPONSES_AND_CHECK_NOTIFY already issues xen_wmb, no
need to add one explicitly.
- After pushing responses, must issue xen_wmb (not xen_rmb) before
hypervisor_notify_via_evtchn.
To generate a diff of this commit:
cvs rdiff -u -r1.109 -r1.110 src/sys/arch/xen/xen/xennetback_xenbus.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/xen/xen/xennetback_xenbus.c
diff -u src/sys/arch/xen/xen/xennetback_xenbus.c:1.109 src/sys/arch/xen/xen/xennetback_xenbus.c:1.110
--- src/sys/arch/xen/xen/xennetback_xenbus.c:1.109 Sat Feb 25 00:34:13 2023
+++ src/sys/arch/xen/xen/xennetback_xenbus.c Sat Feb 25 00:34:25 2023
@@ -1,4 +1,4 @@
-/* $NetBSD: xennetback_xenbus.c,v 1.109 2023/02/25 00:34:13 riastradh Exp $ */
+/* $NetBSD: xennetback_xenbus.c,v 1.110 2023/02/25 00:34:25 riastradh Exp $ */
/*
* Copyright (c) 2006 Manuel Bouyer.
@@ -25,7 +25,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: xennetback_xenbus.c,v 1.109 2023/02/25 00:34:13 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: xennetback_xenbus.c,v 1.110 2023/02/25 00:34:25 riastradh Exp $");
#include <sys/types.h>
#include <sys/param.h>
@@ -1022,14 +1022,13 @@ xennetback_rx_copy_process(struct ifnet
}
/* update pointer */
- xen_rmb();
xneti->xni_rxring.req_cons += queued;
xneti->xni_rxring.rsp_prod_pvt += queued;
RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&xneti->xni_rxring, notify);
/* send event */
if (notify) {
- xen_rmb();
+ xen_wmb();
XENPRINTF(("%s receive event\n",
xneti->xni_if.if_xname));
hypervisor_notify_via_evtchn(xneti->xni_evtchn);
