Avoid race between {,__de}allocate_stack and __reclaim_stacks during fork

nptl/ChangeLog

@@ -1,3 +1,12 @@
+2011-09-15  Andreas Schwab  <schwab@redhat.com>
+
+	* sysdeps/pthread/list.h: Define only list_t if __need_list_t is
+	defined.
+	(list_add): Add atomic_write_barrier.
+	* descr.h: Define __need_list_t before including <list.h>.
+	* nptl-init.c: Include <list.h>
+	* allocatestack.c: Likewise.
+
 2011-09-11  Ulrich Drepper  <drepper@gmail.com>
 
 	* sysdeps/i386/tls.h: Remove HAVE_TLS_SUPPORT test.

nptl/allocatestack.c

@@ -28,6 +28,7 @@
 #include <dl-sysdep.h>
 #include <dl-tls.h>
 #include <tls.h>
+#include <list.h>
 #include <lowlevellock.h>
 #include <kernel-features.h>
 

nptl/descr.h

@@ -26,6 +26,7 @@
 #include <stdbool.h>
 #include <sys/types.h>
 #include <hp-timing.h>
+#define __need_list_t
 #include <list.h>
 #include <lowlevellock.h>
 #include <pthreaddef.h>

nptl/nptl-init.c

@@ -29,6 +29,7 @@
 #include <atomic.h>
 #include <ldsodefs.h>
 #include <tls.h>
+#include <list.h>
 #include <fork.h>
 #include <version.h>
 #include <shlib-compat.h>

nptl/sysdeps/pthread/list.h

@@ -1,4 +1,4 @@
-/* Copyright (C) 2002, 2009 Free Software Foundation, Inc.
+/* Copyright (C) 2002, 2009, 2011 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
 
@@ -18,20 +18,32 @@
    02111-1307 USA.  */
 
 #ifndef _LIST_H
+
+#ifndef __need_list_t
 # define _LIST_H	1
+#endif
 
 /* The definitions of this file are adopted from those which can be
    found in the Linux kernel headers to enable people familiar with
    the latter find their way in these sources as well.  */
 
 
+#if defined __need_list_t || defined _LIST_H
+# ifndef __list_t_defined
+#  define __list_t_defined
 /* Basic type for the double-link list.  */
 typedef struct list_head
 {
   struct list_head *next;
   struct list_head *prev;
 } list_t;
+# endif
+# undef __need_list_t
+#endif
 
+#ifdef _LIST_H
+
+# include <atomic.h>
 
 /* Define a variable with the head and tail of the list.  */
 # define LIST_HEAD(name) \
@@ -49,6 +61,7 @@ list_add (list_t *newp, list_t *head)
   newp->next = head->next;
   newp->prev = head;
   head->next->prev = newp;
+  atomic_write_barrier ();
   head->next = newp;
 }
 
@@ -100,4 +113,6 @@ list_splice (list_t *add, list_t *head)
        pos != (head); \
        pos = p, p = pos->prev)
 
+#endif /* _LIST_H */
+
 #endif	/* list.h */

nptl_db/ChangeLog

@@ -1,3 +1,7 @@
+2011-09-15  Andreas Schwab  <schwab@redhat.com>
+
+	* thread_dbP.h: Include <list.h>
+
 2009-08-23  Roland McGrath  <roland@redhat.com>
 
 	* td_ta_map_lwp2thr.c (__td_ta_lookup_th_unique): Move ta_ok check

nptl_db/thread_dbP.h

@@ -1,5 +1,5 @@
 /* Private header for thread debug library
-   Copyright (C) 2003, 2004, 2007 Free Software Foundation, Inc.
+   Copyright (C) 2003, 2004, 2007, 2011 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -29,6 +29,7 @@
 #include "proc_service.h"
 #include "thread_db.h"
 #include "../nptl/pthreadP.h"  	/* This is for *_BITMASK only.  */
+#include <list.h>
 
 /* Indeces for the symbol names.  */
 enum