Module Name: src
Committed By: riastradh
Date: Sun Jun 13 14:46:07 UTC 2021
Modified Files:
src/sys/dev/usb: uhub.c
Log Message:
uhub(4): Defer rescan to USB event thread.
Keep all of the USB bus exploration in a single thread -- this
appears to have been the original assumption, violated back in 2008
when uhub_rescan was added, and will make everything simpler.
To generate a diff of this commit:
cvs rdiff -u -r1.151 -r1.152 src/sys/dev/usb/uhub.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/dev/usb/uhub.c
diff -u src/sys/dev/usb/uhub.c:1.151 src/sys/dev/usb/uhub.c:1.152
--- src/sys/dev/usb/uhub.c:1.151 Sun Jun 13 00:11:57 2021
+++ src/sys/dev/usb/uhub.c Sun Jun 13 14:46:07 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: uhub.c,v 1.151 2021/06/13 00:11:57 riastradh Exp $ */
+/* $NetBSD: uhub.c,v 1.152 2021/06/13 14:46:07 riastradh Exp $ */
/* $FreeBSD: src/sys/dev/usb/uhub.c,v 1.18 1999/11/17 22:33:43 n_hibma Exp $ */
/* $OpenBSD: uhub.c,v 1.86 2015/06/29 18:27:40 mpi Exp $ */
@@ -37,7 +37,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: uhub.c,v 1.151 2021/06/13 00:11:57 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: uhub.c,v 1.152 2021/06/13 14:46:07 riastradh Exp $");
#ifdef _KERNEL_OPT
#include "opt_usb.h"
@@ -119,6 +119,7 @@ struct uhub_softc {
bool sc_explorepending;
bool sc_first_explore;
bool sc_running;
+ bool sc_rescan;
struct lwp *sc_exploring;
};
@@ -130,8 +131,6 @@ struct uhub_softc {
#define PORTSTAT_ISSET(sc, port) \
((sc)->sc_status[(port) / 8] & (1 << ((port) % 8)))
-Static usbd_status uhub_explore_enter(struct uhub_softc *);
-Static void uhub_explore_exit(struct uhub_softc *);
Static usbd_status uhub_explore(struct usbd_device *);
Static void uhub_intr(struct usbd_xfer *, void *, usbd_status);
@@ -482,51 +481,17 @@ uhub_attach(device_t parent, device_t se
config_pending_decr(self);
}
-Static usbd_status
-uhub_explore_enter(struct uhub_softc *sc)
-{
- usbd_status err;
-
- mutex_enter(&sc->sc_lock);
- for (;;) {
- if (sc->sc_exploring == NULL) {
- sc->sc_exploring = curlwp;
- err = 0;
- break;
- }
- KASSERT(sc->sc_exploring != curlwp);
- if (cv_wait_sig(&sc->sc_cv, &sc->sc_lock)) {
- err = USBD_INTERRUPTED;
- break;
- }
- }
- mutex_exit(&sc->sc_lock);
-
- return err;
-}
-
-Static void
-uhub_explore_exit(struct uhub_softc *sc)
-{
-
- mutex_enter(&sc->sc_lock);
- KASSERTMSG(sc->sc_exploring == curlwp, "lwp %p exploring %s",
- sc->sc_exploring, device_xname(sc->sc_dev));
- sc->sc_exploring = NULL;
- cv_broadcast(&sc->sc_cv);
- mutex_exit(&sc->sc_lock);
-}
-
usbd_status
uhub_explore(struct usbd_device *dev)
{
usb_hub_descriptor_t *hd = &dev->ud_hub->uh_hubdesc;
struct uhub_softc *sc = dev->ud_hub->uh_hubsoftc;
struct usbd_port *up;
+ struct usbd_device *subdev;
usbd_status err;
int speed;
int port;
- int change, status, reconnect;
+ int change, status, reconnect, rescan;
UHUBHIST_FUNC();
UHUBHIST_CALLARGS("uhub%jd dev=%#jx addr=%jd speed=%ju",
@@ -542,10 +507,19 @@ uhub_explore(struct usbd_device *dev)
if (dev->ud_depth > USB_HUB_MAX_DEPTH)
return USBD_TOO_DEEP;
- /* Only one explore at a time, please. */
- err = uhub_explore_enter(sc);
- if (err)
- return err;
+ /* Process rescan if requested. */
+ mutex_enter(&sc->sc_lock);
+ rescan = sc->sc_rescan;
+ sc->sc_rescan = false;
+ mutex_exit(&sc->sc_lock);
+ if (rescan) {
+ for (port = 1; port <= hd->bNbrPorts; port++) {
+ subdev = dev->ud_hub->uh_ports[port - 1].up_dev;
+ if (subdev == NULL)
+ continue;
+ usbd_reattach_device(sc->sc_dev, subdev, port, NULL);
+ }
+ }
if (PORTSTAT_ISSET(sc, 0)) { /* hub status change */
usb_hub_status_t hs;
@@ -851,7 +825,6 @@ uhub_explore(struct usbd_device *dev)
}
}
mutex_exit(&sc->sc_lock);
- uhub_explore_exit(sc);
if (sc->sc_first_explore) {
config_pending_decr(sc->sc_dev);
sc->sc_first_explore = false;
@@ -928,26 +901,17 @@ static int
uhub_rescan(device_t self, const char *ifattr, const int *locators)
{
struct uhub_softc *sc = device_private(self);
- struct usbd_hub *hub = sc->sc_hub->ud_hub;
- struct usbd_device *dev;
- int port;
UHUBHIST_FUNC();
UHUBHIST_CALLARGS("uhub%jd", device_unit(sc->sc_dev), 0, 0, 0);
KASSERT(KERNEL_LOCKED_P());
- if (uhub_explore_enter(sc) != 0)
- return EBUSY;
- for (port = 1; port <= hub->uh_hubdesc.bNbrPorts; port++) {
- dev = hub->uh_ports[port - 1].up_dev;
- if (dev == NULL)
- continue;
- usbd_reattach_device(sc->sc_dev, dev, port, locators);
- }
- uhub_explore_exit(sc);
-
- /* Arrange to recursively explore hubs we may have found. */
+ /* Trigger bus exploration. */
+ /* XXX locators */
+ mutex_enter(&sc->sc_lock);
+ sc->sc_rescan = true;
+ mutex_exit(&sc->sc_lock);
usb_needs_explore(sc->sc_hub);
return 0;
