syscons - Fix comments related to do_switch_scr()

do_switch_scr() no longer releases critical sections so all
the comments remarking this are now wrong, remove them.

Most of the code uses now tty_token for the non-critical paths
and it no longer needs a critical section.

Pointed-out-by: @dillon

diff --git a/sys/dev/misc/syscons/syscons.c b/sys/dev/misc/syscons/syscons.c
index a721f41..618cfe4 100644 (file)
--- a/sys/dev/misc/syscons/syscons.c
+++ b/sys/dev/misc/syscons/syscons.c
@@ -570,10 +570,6 @@ scclose(struct dev_close_args *ap)
        DPRINTF(5, ("sc%d: scclose(), ", scp->sc->unit));
        if ((scp == scp->sc->cur_scp) && (scp->sc->unit == sc_console_unit))
            cons_unavail = FALSE;
-       /* 
-        * note: must be called from a critical section because finish_vt_rel
-        * will call do_switch_scr which releases it temporarily 
-        */
        if (finish_vt_rel(scp, TRUE) == 0)      /* force release */
            DPRINTF(5, ("reset WAIT_REL, "));
        if (finish_vt_acq(scp) == 0)            /* force acknowledge */
@@ -981,11 +977,6 @@ scioctl(struct dev_ioctl_args *ap)
            DPRINTF(5, ("VT_AUTO, "));
            if ((scp == sc->cur_scp) && (sc->unit == sc_console_unit))
                cons_unavail = FALSE;
-           /* 
-            * note: must be called from a critical section because 
-            * finish_vt_rel will call do_switch_scr which releases it
-            * temporarily.
-            */
            if (finish_vt_rel(scp, TRUE) == 0)
                DPRINTF(5, ("reset WAIT_REL, "));
            if (finish_vt_acq(scp) == 0)
@@ -1040,20 +1031,10 @@ scioctl(struct dev_ioctl_args *ap)
        error = EINVAL;
        switch(*(int *)data) {
        case VT_FALSE:          /* user refuses to release screen, abort */
-           /* 
-            * note: must be called from a critical section because 
-            * finish_vt_rel will call do_switch_scr which releases it
-            * temporarily.
-            */
            if ((error = finish_vt_rel(scp, FALSE)) == 0)
                DPRINTF(5, ("sc%d: VT_FALSE\n", sc->unit));
            break;
        case VT_TRUE:           /* user has released screen, go on */
-           /* 
-            * note: must be called from a critical section because 
-            * finish_vt_rel will call do_switch_scr which releases it
-            * temporarily.
-            */
            if ((error = finish_vt_rel(scp, TRUE)) == 0)
                DPRINTF(5, ("sc%d: VT_TRUE\n", sc->unit));
            break;
@@ -2368,9 +2349,6 @@ sc_switch_scr(sc_softc_t *sc, u_int next_scr)
                 * Force the previous switch to finish, but return now 
                 * with error.
                 *
-                * note: must be called from a critical section because 
-                * finish_vt_rel will call do_switch_scr which releases it
-                * temporarily.
                 */
                DPRINTF(5, ("reset WAIT_REL, "));
                finish_vt_rel(cur_scp, TRUE);
@@ -2412,9 +2390,6 @@ sc_switch_scr(sc_softc_t *sc, u_int next_scr)
                     * Act as if the controlling program returned
                     * VT_FALSE.
                     *
-                    * note: must be called from a critical section because 
-                    * finish_vt_rel will call do_switch_scr which releases it
-                    * temporarily.
                     */
                    DPRINTF(5, ("force reset WAIT_REL, "));
                    finish_vt_rel(cur_scp, FALSE);
@@ -2529,10 +2504,6 @@ sc_switch_scr(sc_softc_t *sc, u_int next_scr)
     return 0;
 }
 
-/*
- * NOTE: must be called from a critical section because do_switch_scr
- * will release it temporarily.
- */
 static void
 do_switch_scr(sc_softc_t *sc)
 {
@@ -2608,10 +2579,6 @@ signal_vt_acq(scr_stat *scp)
     return TRUE;
 }
 
-/*
- * NOTE: must be called from a critical section because do_switch_scr
- * will release it temporarily.
- */
 static int
 finish_vt_rel(scr_stat *scp, int release)
 {