[src/trunk]: src/sys/arch/xen/xenbus xenbus_comms.c: Membar audit.

[riastradh <riastradh%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/c416f9775bfe
branches:  trunk
changeset: 373718:c416f9775bfe
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Sat Feb 25 00:34:01 2023 +0000

description:
xenbus_comms.c: Membar audit.

This had the sense of membars reversed, presumably because xen_rmb
and xen_wmb had gotten reversed at some point.

diffstat:

 sys/arch/xen/xenbus/xenbus_comms.c |  12 ++++++------
 1 files changed, 6 insertions(+), 6 deletions(-)

diffs (42 lines):

diff -r 7fefbfbf02f0 -r c416f9775bfe sys/arch/xen/xenbus/xenbus_comms.c
--- a/sys/arch/xen/xenbus/xenbus_comms.c        Sat Feb 25 00:33:50 2023 +0000
+++ b/sys/arch/xen/xenbus/xenbus_comms.c        Sat Feb 25 00:34:01 2023 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: xenbus_comms.c,v 1.24 2020/05/13 13:19:38 jdolecek Exp $ */
+/* $NetBSD: xenbus_comms.c,v 1.25 2023/02/25 00:34:01 riastradh Exp $ */
 /******************************************************************************
  * xenbus_comms.c
  *
@@ -29,7 +29,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: xenbus_comms.c,v 1.24 2020/05/13 13:19:38 jdolecek Exp $");
+__KERNEL_RCSID(0, "$NetBSD: xenbus_comms.c,v 1.25 2023/02/25 00:34:01 riastradh Exp $");
 
 #include <sys/types.h>
 #include <sys/null.h> 
@@ -153,9 +153,9 @@
                len -= avail;
 
                /* Other side must not see new header until data is there. */
-               xen_rmb();
+               xen_wmb();
                intf->req_prod += avail;
-               xen_rmb();
+               xen_wmb();
 
                hypervisor_notify_via_evtchn(xen_start_info.store_evtchn);
        }
@@ -202,9 +202,9 @@
                len -= avail;
 
                /* Other side must not see free space until we've copied out */
-               xen_rmb();
+               xen_wmb();
                intf->rsp_cons += avail;
-               xen_rmb();
+               xen_wmb();
 
                XENPRINTF(("Finished read of %i bytes (%i to go)\n",
                    avail, len));