[src/trunk]: src/sys/dev/usb usbnet: No need for the core lock in usbnet_iffl...

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

details:   https://anonhg.NetBSD.org/src/rev/7f11a4d5d7b5
branches:  trunk
changeset: 362525:7f11a4d5d7b5
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Thu Mar 03 05:52:27 2022 +0000

description:
usbnet: No need for the core lock in usbnet_ifflags_cb.

The only state this touches is unp_if_flags, and all paths touching
it also hold IFNET_LOCK -- not to mention this is the only path that
touches unp_if_flags in the first place!

diffstat:

 sys/dev/usb/usbnet.c |  8 ++------
 1 files changed, 2 insertions(+), 6 deletions(-)

diffs (36 lines):

diff -r d9d04265779e -r 7f11a4d5d7b5 sys/dev/usb/usbnet.c
--- a/sys/dev/usb/usbnet.c      Thu Mar 03 05:52:20 2022 +0000
+++ b/sys/dev/usb/usbnet.c      Thu Mar 03 05:52:27 2022 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: usbnet.c,v 1.79 2022/03/03 05:52:20 riastradh Exp $    */
+/*     $NetBSD: usbnet.c,v 1.80 2022/03/03 05:52:27 riastradh Exp $    */
 
 /*
  * Copyright (c) 2019 Matthew R. Green
@@ -31,7 +31,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: usbnet.c,v 1.79 2022/03/03 05:52:20 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: usbnet.c,v 1.80 2022/03/03 05:52:27 riastradh Exp $");
 
 #include <sys/param.h>
 #include <sys/kernel.h>
@@ -987,8 +987,6 @@
 
        KASSERTMSG(IFNET_LOCKED(ifp), "%s", ifp->if_xname);
 
-       mutex_enter(&unp->unp_core_lock);
-
        const u_short changed = ifp->if_flags ^ unp->unp_if_flags;
        if ((changed & ~(IFF_CANTCHANGE | IFF_DEBUG)) == 0) {
                unp->unp_if_flags = ifp->if_flags;
@@ -998,8 +996,6 @@
                rv = ENETRESET;
        }
 
-       mutex_exit(&unp->unp_core_lock);
-
        return rv;
 }