Thu Mar 3 05:49:29 2022 UTC ()

usbnet: Omit needless locking/busying/testing in usbnet_tick_task.

usbnet_stop waits for the task to complete before resetting the
hardware, and usbnet_detach waits for usbnet_stop to complete before
destroying anything, so there's no need for any of this.


(riastradh)

diff -r1.64 -r1.65 src/sys/dev/usb/usbnet.c

--- src/sys/dev/usb/usbnet.c 2022/03/03 05:49:22	1.64
+++ src/sys/dev/usb/usbnet.c 2022/03/03 05:49:29	1.65

 @@ -1,14 +1,14 @@
-/*	$NetBSD: usbnet.c,v 1.64 2022/03/03 05:49:22 riastradh Exp $	*/
+/*	$NetBSD: usbnet.c,v 1.65 2022/03/03 05:49:29 riastradh Exp $	*/
 /*
  * Copyright (c) 2019 Matthew R. Green
  * All rights reserved.
+ *
  * 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.
 @@ -21,27 +21,27 @@
  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
 /*
  * Common code shared between USB network drivers.
  */
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: usbnet.c,v 1.64 2022/03/03 05:49:22 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: usbnet.c,v 1.65 2022/03/03 05:49:29 riastradh Exp $");
 #include <sys/param.h>
 #include <sys/kernel.h>
 #include <sys/kmem.h>
 #include <sys/module.h>
 #include <sys/atomic.h>
 #include <dev/usb/usbnet.h>
 #include <dev/usb/usbhist.h>
 struct usbnet_cdata {
 	struct usbnet_chain	*uncd_tx_chain;
 	struct usbnet_chain	*uncd_rx_chain;
 @@ -1229,63 +1229,50 @@ usbnet_watchdog(struct ifnet *ifp)
 			DPRINTF("uncd_tx_cnt now %ju", cd->uncd_tx_cnt, 0, 0, 0);
+	}
 	if (!IFQ_IS_EMPTY(&ifp->if_snd))
 		(*ifp->if_start)(ifp);
+}
 static void
 usbnet_tick_task(void *arg)
+{
 	USBNETHIST_FUNC();
 	struct usbnet * const un = arg;
 	struct usbnet_private * const unp = un->un_pri;
 	USBNETHIST_CALLARGSN(8, "%jd: enter", unp->unp_number, 0, 0, 0);
 	mutex_enter(&unp->unp_core_lock);
 	if (unp->unp_stopping || unp->unp_dying) {
 		mutex_exit(&unp->unp_core_lock);
 		return;
 	struct ifnet * const ifp = usbnet_ifp(un);
 	struct mii_data * const mii = usbnet_mii(un);
-	KASSERT(ifp != NULL);	/* embedded member */
+	USBNETHIST_CALLARGSN(8, "%jd: enter", unp->unp_number, 0, 0, 0);
 	usbnet_busy(un);
 	mutex_exit(&unp->unp_core_lock);
 	mutex_enter(&unp->unp_txlock);
 	const bool timeout = unp->unp_timer != 0 && --unp->unp_timer == 0;
 	mutex_exit(&unp->unp_txlock);
 	if (timeout)
 		usbnet_watchdog(ifp);
 	DPRINTFN(8, "mii %#jx ifp %#jx", (uintptr_t)mii, (uintptr_t)ifp, 0, 0);
 	if (mii) {
 		mutex_enter(&unp->unp_core_lock);
 		mii_tick(mii);
 		if (!unp->unp_link)
 			(*mii->mii_statchg)(ifp);
 		mutex_exit(&unp->unp_core_lock);
+	}
 	/* Call driver if requested. */
 	uno_tick(un);
 	mutex_enter(&unp->unp_core_lock);
 	usbnet_unbusy(un);
 	if (!unp->unp_stopping && !unp->unp_dying)
 		callout_schedule(&unp->unp_stat_ch, hz);
 	mutex_exit(&unp->unp_core_lock);
+}
 static int
 usbnet_if_init(struct ifnet *ifp)
+{
 	USBNETHIST_FUNC(); USBNETHIST_CALLED();
 	struct usbnet * const un = ifp->if_softc;
 	bool dying;
 	KASSERTMSG(IFNET_LOCKED(ifp), "%s", ifp->if_xname);