[src/trunk]: src/sys/net - deal with softint_establish failure

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

details:   https://anonhg.NetBSD.org/src/rev/38f611c049f1
branches:  trunk
changeset: 789487:38f611c049f1
user:      yamt <yamt%NetBSD.org@localhost>
date:      Tue Aug 20 12:28:12 2013 +0000

description:
- deal with softint_establish failure
- establish softint only when necessary

diffstat:

 sys/net/if_tap.c |  30 ++++++++++++++++++++++++------
 1 files changed, 24 insertions(+), 6 deletions(-)

diffs (74 lines):

diff -r 557b61529779 -r 38f611c049f1 sys/net/if_tap.c
--- a/sys/net/if_tap.c  Tue Aug 20 10:33:03 2013 +0000
+++ b/sys/net/if_tap.c  Tue Aug 20 12:28:12 2013 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if_tap.c,v 1.70 2013/01/28 15:05:03 yamt Exp $ */
+/*     $NetBSD: if_tap.c,v 1.71 2013/08/20 12:28:12 yamt Exp $ */
 
 /*
  *  Copyright (c) 2003, 2004, 2008, 2009 The NetBSD Foundation.
@@ -33,7 +33,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_tap.c,v 1.70 2013/01/28 15:05:03 yamt Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_tap.c,v 1.71 2013/08/20 12:28:12 yamt Exp $");
 
 #if defined(_KERNEL_OPT)
 
@@ -268,7 +268,7 @@
        char enaddrstr[3 * ETHER_ADDR_LEN];
 
        sc->sc_dev = self;
-       sc->sc_sih = softint_establish(SOFTINT_CLOCK, tap_softintr, sc);
+       sc->sc_sih = NULL;
        getnanotime(&sc->sc_btime);
        sc->sc_atime = sc->sc_mtime = sc->sc_btime;
 
@@ -391,7 +391,10 @@
        if_down(ifp);
        splx(s);
 
-       softint_disestablish(sc->sc_sih);
+       if (sc->sc_sih != NULL) {
+               softint_disestablish(sc->sc_sih);
+               sc->sc_sih = NULL;
+       }
 
 #if defined(COMPAT_40) || defined(MODULAR)
        /*
@@ -852,6 +855,10 @@
        }
        splx(s);
 
+       if (sc->sc_sih != NULL) {
+               softint_disestablish(sc->sc_sih);
+               sc->sc_sih = NULL;
+       }
        sc->sc_flags &= ~(TAP_INUSE | TAP_ASYNCIO);
 
        return (0);
@@ -1104,10 +1111,21 @@
        case FIOGETOWN:
                return fgetown(sc->sc_pgid, cmd, data);
        case FIOASYNC:
-               if (*(int *)data)
+               if (*(int *)data) {
+                       if (sc->sc_sih == NULL) {
+                               sc->sc_sih = softint_establish(SOFTINT_CLOCK,
+                                   tap_softintr, sc);
+                               if (sc->sc_sih == NULL)
+                                       return EBUSY; /* XXX */
+                       }
                        sc->sc_flags |= TAP_ASYNCIO;
-               else
+               } else {
                        sc->sc_flags &= ~TAP_ASYNCIO;
+                       if (sc->sc_sih != NULL) {
+                               softint_disestablish(sc->sc_sih);
+                               sc->sc_sih = NULL;
+                       }
+               }
                return 0;
        case FIONBIO:
                if (*(int *)data)