[src-draft/trunk]: src/sys/dev/usb No need to hold two locks.

[Nathanial Sloss <nat%netbsd.org@localhost>]

details:   https://anonhg.NetBSD.org/src-all/rev/055aad2b5d77
branches:  trunk
changeset: 369390:055aad2b5d77
user:      Nathanial Sloss <nat%netbsd.org@localhost>
date:      Fri Aug 05 23:32:36 2022 +1000

description:
No need to hold two locks.

diffstat:

 sys/dev/usb/if_urtwn.c |  12 ++----------
 1 files changed, 2 insertions(+), 10 deletions(-)

diffs (58 lines):

diff -r 476ff48c78c4 -r 055aad2b5d77 sys/dev/usb/if_urtwn.c
--- a/sys/dev/usb/if_urtwn.c    Fri Aug 05 23:30:49 2022 +1000
+++ b/sys/dev/usb/if_urtwn.c    Fri Aug 05 23:32:36 2022 +1000
@@ -674,7 +674,6 @@
        struct ieee80211vap *vap;
        struct urtwn_host_cmd_ring *ring = &sc->cmdq;
        struct urtwn_host_cmd *cmd;
-       int s;
 
        URTWNHIST_FUNC(); URTWNHIST_CALLED();
 
@@ -700,22 +699,18 @@
        usbwifi_unlock_ic(&sc->sc_uw);
 
        /* Process host commands. */
-       s = splusb();
        mutex_spin_enter(&sc->sc_task_mtx);
        while (ring->next != ring->cur) {
                cmd = &ring->cmd[ring->next];
+               ring->queued--;
+               ring->next = (ring->next + 1) % URTWN_HOST_CMD_RING_COUNT;
                mutex_spin_exit(&sc->sc_task_mtx);
-               splx(s);
                /* Invoke callback with kernel lock held. */
                cmd->cb(sc, cmd->data);
-               s = splusb();
                mutex_spin_enter(&sc->sc_task_mtx);
-               ring->queued--;
-               ring->next = (ring->next + 1) % URTWN_HOST_CMD_RING_COUNT;
        }
        cv_broadcast(&sc->sc_task_cv);
        mutex_spin_exit(&sc->sc_task_mtx);
-       splx(s);
 }
 
 static void
@@ -725,13 +720,11 @@
 {
        struct urtwn_host_cmd_ring *ring = &sc->cmdq;
        struct urtwn_host_cmd *cmd;
-       int s;
 
        URTWNHIST_FUNC(); URTWNHIST_CALLED();
        DPRINTFN(DBG_FN, "cb=%jd, arg=%jd, len=%jd", (intptr_t)cb,
            (intptr_t)arg, len, 0);
 
-       s = splusb();
        mutex_spin_enter(&sc->sc_task_mtx);
        cmd = &ring->cmd[ring->cur];
        cmd->cb = cb;
@@ -745,7 +738,6 @@
                usb_add_task(sc->sc_uw.uw_udev, &sc->sc_task, USB_TASKQ_DRIVER);
        } else
                mutex_spin_exit(&sc->sc_task_mtx);
-       splx(s);
 }
 
 __unused static void