[src/netbsd-3]: src/sys/kern Pull up revision 1.150 (requested by yamt in tic...

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

details:   https://anonhg.NetBSD.org/src/rev/bf012ee9d6fa
branches:  netbsd-3
changeset: 577010:bf012ee9d6fa
user:      tron <tron%NetBSD.org@localhost>
date:      Sun Aug 21 22:06:14 2005 +0000

description:
Pull up revision 1.150 (requested by yamt in ticket #679):
exit_lwps: fix a race with eg. sa_setwoken.
ie. "exit_lwps: lwp_wait1 failed with error 11"
PR/30689.

diffstat:

 sys/kern/kern_exit.c |  13 +++++++++++--
 1 files changed, 11 insertions(+), 2 deletions(-)

diffs (41 lines):

diff -r 3ad7293ef406 -r bf012ee9d6fa sys/kern/kern_exit.c
--- a/sys/kern/kern_exit.c      Sun Aug 21 22:04:22 2005 +0000
+++ b/sys/kern/kern_exit.c      Sun Aug 21 22:06:14 2005 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: kern_exit.c,v 1.145.2.1 2005/08/21 22:04:22 tron Exp $ */
+/*     $NetBSD: kern_exit.c,v 1.145.2.2 2005/08/21 22:06:14 tron Exp $ */
 
 /*-
  * Copyright (c) 1998, 1999 The NetBSD Foundation, Inc.
@@ -74,7 +74,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_exit.c,v 1.145.2.1 2005/08/21 22:04:22 tron Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_exit.c,v 1.145.2.2 2005/08/21 22:06:14 tron Exp $");
 
 #include "opt_ktrace.h"
 #include "opt_perfctrs.h"
@@ -590,6 +590,7 @@
                }
        }
 
+retry:
        /*
         * Interrupt LWPs in interruptable sleep, unsuspend suspended
         * LWPs, make detached LWPs undetached (so we can wait for
@@ -613,6 +614,14 @@
                DPRINTF(("exit_lwps: waiting for %d LWPs (%d runnable, %d zombies)\n",
                    p->p_nlwps, p->p_nrlwps, p->p_nzlwps));
                error = lwp_wait1(l, 0, &waited, LWPWAIT_EXITCONTROL);
+               if (error == EDEADLK) {
+                       /*
+                        * LWPs can get suspended/slept behind us.
+                        * (eg. sa_setwoken)
+                        * kick them again and retry.
+                        */
+                       goto retry;
+               }
                if (error)
                        panic("exit_lwps: lwp_wait1 failed with error %d\n",
                            error);