Module Name: src
Committed By: dyoung
Date: Wed Oct 19 21:59:38 UTC 2011
Modified Files:
src/sys/net: if_gre.c
Log Message:
Get rid of gre's deadlock-prone, one-off ifioctl locking. The standard
ifioctl locking will do.
To generate a diff of this commit:
cvs rdiff -u -r1.145 -r1.146 src/sys/net/if_gre.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/net/if_gre.c
diff -u src/sys/net/if_gre.c:1.145 src/sys/net/if_gre.c:1.146
--- src/sys/net/if_gre.c:1.145 Tue May 24 16:37:49 2011
+++ src/sys/net/if_gre.c Wed Oct 19 21:59:38 2011
@@ -1,4 +1,4 @@
-/* $NetBSD: if_gre.c,v 1.145 2011/05/24 16:37:49 joerg Exp $ */
+/* $NetBSD: if_gre.c,v 1.146 2011/10/19 21:59:38 dyoung Exp $ */
/*
* Copyright (c) 1998, 2008 The NetBSD Foundation, Inc.
@@ -45,7 +45,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_gre.c,v 1.145 2011/05/24 16:37:49 joerg Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_gre.c,v 1.146 2011/10/19 21:59:38 dyoung Exp $");
#include "opt_atalk.h"
#include "opt_gre.h"
@@ -266,14 +266,6 @@ greintr(void *arg)
/* Caller must hold sc->sc_mtx. */
static void
-gre_wait(struct gre_softc *sc)
-{
- sc->sc_waiters++;
- cv_wait(&sc->sc_condvar, &sc->sc_mtx);
- sc->sc_waiters--;
-}
-
-static void
gre_fp_wait(struct gre_softc *sc)
{
sc->sc_fp_waiters++;
@@ -362,7 +354,6 @@ gre_clone_create(struct if_clone *ifc, i
if_attach(&sc->sc_if);
if_alloc_sadl(&sc->sc_if);
bpf_attach(&sc->sc_if, DLT_NULL, sizeof(uint32_t));
- sc->sc_state = GRE_S_IDLE;
return 0;
}
@@ -378,23 +369,6 @@ gre_clone_destroy(struct ifnet *ifp)
s = splnet();
if_detach(ifp);
- /* Some LWPs may still wait in gre_ioctl_lock(), however,
- * no new LWP will enter gre_ioctl_lock(), because ifunit()
- * cannot locate the interface any longer.
- */
- mutex_enter(&sc->sc_mtx);
- GRE_DPRINTF(sc, "\n");
- while (sc->sc_state != GRE_S_IDLE)
- gre_wait(sc);
- GRE_DPRINTF(sc, "\n");
- sc->sc_state = GRE_S_DIE;
- cv_broadcast(&sc->sc_condvar);
- while (sc->sc_waiters > 0)
- cv_wait(&sc->sc_condvar, &sc->sc_mtx);
- /* At this point, no other LWP will access the gre_softc, so
- * we can release the mutex.
- */
- mutex_exit(&sc->sc_mtx);
GRE_DPRINTF(sc, "\n");
/* Note that we must not hold the mutex while we call gre_reconf(). */
gre_reconf(sc, NULL);
@@ -1242,39 +1216,6 @@ gre_clearconf(struct gre_soparm *sp, boo
}
static int
-gre_ioctl_lock(struct gre_softc *sc)
-{
- mutex_enter(&sc->sc_mtx);
-
- while (sc->sc_state == GRE_S_IOCTL)
- gre_wait(sc);
-
- if (sc->sc_state != GRE_S_IDLE) {
- cv_signal(&sc->sc_condvar);
- mutex_exit(&sc->sc_mtx);
- GRE_DPRINTF(sc, "\n");
- return ENXIO;
- }
-
- sc->sc_state = GRE_S_IOCTL;
-
- mutex_exit(&sc->sc_mtx);
- return 0;
-}
-
-static void
-gre_ioctl_unlock(struct gre_softc *sc)
-{
- mutex_enter(&sc->sc_mtx);
-
- KASSERT(sc->sc_state == GRE_S_IOCTL);
- sc->sc_state = GRE_S_IDLE;
- cv_signal(&sc->sc_condvar);
-
- mutex_exit(&sc->sc_mtx);
-}
-
-static int
gre_ioctl(struct ifnet *ifp, const u_long cmd, void *data)
{
struct ifreq *ifr;
@@ -1308,10 +1249,6 @@ gre_ioctl(struct ifnet *ifp, const u_lon
break;
}
- if ((error = gre_ioctl_lock(sc)) != 0) {
- GRE_DPRINTF(sc, "\n");
- return error;
- }
s = splnet();
sp0 = sc->sc_soparm;
@@ -1549,7 +1486,6 @@ gre_ioctl(struct ifnet *ifp, const u_lon
out:
GRE_DPRINTF(sc, "\n");
splx(s);
- gre_ioctl_unlock(sc);
return error;
}
