2007-06-09 Ulrich Drepper <drepper@redhat.com>

	* elf/do-lookup.h (do_lookup_x): Read r_nlist before r_list and
	make sure gcc doesn't mess around with this.

2007-06-08  Ulrich Drepper  <drepper@redhat.com>

	* elf/dl-lookup.c (_dl_lookup_symbol_x): Remove use of r_nlist.

2007-06-08  Jakub Jelinek  <jakub@redhat.com>

	* elf/dl-close.c (_dl_close_worker): Remove all to be removed
	libraries from the global scope at once and call THREAD_GSCOPE_WAIT

2007-05-18  Ulrich Drepper  <drepper@redhat.com>

	* elf/dl-close.c (_dl_close_worker): When removing object from
	global scope, wait for all lookups to finish afterwards.
	* elf/dl-open.c (add_to_global): When global scope array must
	grow, allocate a new one and free old array only after all
	lookups finish.
	* elf/dl-runtime.c (_dl_fixup): Protect using global scope.
	(_dl_lookup_symbol_x): Likewise.
	* elf/dl-support.c: Define _dl_wait_lookup_done.
	* sysdeps/generic/ldsodefs.h (struct rtld_global): Add
	_dl_wait_lookup_done.

nptl/
2007-05-28  Jakub Jelinek  <jakub@redhat.com>

	* sysdeps/i386/tls.h (THREAD_GSCOPE_RESET_FLAG): Use explicit
	insn suffix.
	(THREAD_GSCOPE_GET_FLAG): Remove.
	* sysdeps/x86_64/tls.h (THREAD_GSCOPE_GET_FLAG): Remove.
	* allocatestack.c (__wait_lookup_done): Revert 2007-05-24
	changes.
	* sysdeps/powerpc/tls.h (tcbhead_t): Remove gscope_flag.
	(THREAD_GSCOPE_GET_FLAG): Remove.
	(THREAD_GSCOPE_RESET_FLAG): Use THREAD_SELF->header.gscope_flag
	instead of THREAD_GSCOPE_GET_FLAG.
	(THREAD_GSCOPE_SET_FLAG): Likewise.  Add atomic_write_barrier after
	it.
	* sysdeps/s390/tls.h (THREAD_GSCOPE_FLAG_UNUSED,
	THREAD_GSCOPE_FLAG_USED, THREAD_GSCOPE_FLAG_WAIT,
	THREAD_GSCOPE_RESET_FLAG, THREAD_GSCOPE_SET_FLAG,
	THREAD_GSCOPE_WAIT): Define.
	* sysdeps/sparc/tls.h (THREAD_GSCOPE_FLAG_UNUSED,
	THREAD_GSCOPE_FLAG_USED, THREAD_GSCOPE_FLAG_WAIT,
	THREAD_GSCOPE_RESET_FLAG, THREAD_GSCOPE_SET_FLAG,
	THREAD_GSCOPE_WAIT): Define.
	* sysdeps/sh/tls.h (THREAD_GSCOPE_FLAG_UNUSED,
	THREAD_GSCOPE_FLAG_USED, THREAD_GSCOPE_FLAG_WAIT,
	THREAD_GSCOPE_RESET_FLAG, THREAD_GSCOPE_SET_FLAG,
	THREAD_GSCOPE_WAIT): Define.
	* sysdeps/ia64/tls.h (THREAD_GSCOPE_FLAG_UNUSED,
	THREAD_GSCOPE_FLAG_USED, THREAD_GSCOPE_FLAG_WAIT,
	THREAD_GSCOPE_RESET_FLAG, THREAD_GSCOPE_SET_FLAG,
	THREAD_GSCOPE_WAIT): Define.

2007-05-24  Richard Henderson  <rth@redhat.com>

	* descr.h (struct pthread): Add header.gscope_flag.
	* sysdeps/alpha/tls.h (THREAD_GSCOPE_FLAG_UNUSED,
	THREAD_GSCOPE_FLAG_USED, THREAD_GSCOPE_FLAG_WAIT,
	THREAD_GSCOPE_RESET_FLAG, THREAD_GSCOPE_SET_FLAG,
	THREAD_GSCOPE_WAIT): Define.

2007-05-26  Ulrich Drepper  <drepper@redhat.com>

	* allocatestack.c: Revert last change.
	* init.c: Likewise.
	* sysdeps/i386/tls.h: Likewise.
	* sysdeps/x86_64/tls.h: Likewise.

2007-05-24  Jakub Jelinek  <jakub@redhat.com>

	* sysdeps/powerpc/tls.h (tcbhead_t): Add gscope_flag.
	(THREAD_GSCOPE_FLAG_UNUSED, THREAD_GSCOPE_FLAG_USED,
	THREAD_GSCOPE_FLAG_WAIT): Define.
	(THREAD_GSCOPE_GET_FLAG, THREAD_GSCOPE_SET_FLAG,
	THREAD_GSCOPE_RESET_FLAG, THREAD_GSCOPE_WAIT): Define.
	* sysdeps/i386/tls.h (THREAD_GSCOPE_WAIT): Don't use
	PTR_DEMANGLE.
	(THREAD_GSCOPE_GET_FLAG): Define.
	* sysdeps/x86_64/tls.h (THREAD_GSCOPE_GET_FLAG): Define.
	* allocatestack.c (__wait_lookup_done): Use THREAD_GSCOPE_GET_FLAG
	instead of ->header.gscope_flag directly.

2007-05-21  Ulrich Drepper  <drepper@redhat.com>

	* sysdeps/pthread/pthread-functions.h (struct pthread_functions):
	Remove ptr_wait_lookup_done again.
	* init.c (pthread_functions): Don't add .ptr_wait_lookup_done here.
	(__pthread_initialize_minimal_internal): Initialize
	_dl_wait_lookup_done pointer in _rtld_global directly.
	* sysdeps/unix/sysv/linux/libc_pthread_init.c (__libc_pthread_init):
	Remove code to code _dl_wait_lookup_done.
	* sysdeps/x86_64/tls.h (THREAD_GSCOPE_WAIT): The pointer is not
	encrypted for now.

2007-05-19  Ulrich Drepper  <drepper@redhat.com>

	* allocatestack.c (__wait_lookup_done): New function.
	* sysdeps/pthread/pthread-functions.h (struct pthread_functions):
	Add ptr_wait_lookup_done.
	* init.c (pthread_functions): Initialize .ptr_wait_lookup_done.
	* pthreadP.h: Declare __wait_lookup_done.
	* sysdeps/i386/tls.h (tcbhead_t): Add gscope_flag.
	Define macros to implement reference handling of global scope.
	* sysdeps/x86_64/tls.h: Likewise.
	* sysdeps/unix/sysv/linux/libc_pthread_init.c (__libc_pthread_init):
	Initialize GL(dl_wait_lookup_done).

14 files changed, 328 insertions, 30 deletions

diff --git a/nptl/ChangeLog b/nptl/ChangeLog
index ea877d0374..bb7dd528ab 100644
--- a/nptl/ChangeLog
+++ b/nptl/ChangeLog
@@ -1,3 +1,88 @@
+2007-05-28  Jakub Jelinek  <jakub@redhat.com>
+
+	* sysdeps/i386/tls.h (THREAD_GSCOPE_RESET_FLAG): Use explicit
+	insn suffix.
+	(THREAD_GSCOPE_GET_FLAG): Remove.
+	* sysdeps/x86_64/tls.h (THREAD_GSCOPE_GET_FLAG): Remove.
+	* allocatestack.c (__wait_lookup_done): Revert 2007-05-24
+	changes.
+	* sysdeps/powerpc/tls.h (tcbhead_t): Remove gscope_flag.
+	(THREAD_GSCOPE_GET_FLAG): Remove.
+	(THREAD_GSCOPE_RESET_FLAG): Use THREAD_SELF->header.gscope_flag
+	instead of THREAD_GSCOPE_GET_FLAG.
+	(THREAD_GSCOPE_SET_FLAG): Likewise.  Add atomic_write_barrier after
+	it.
+	* sysdeps/s390/tls.h (THREAD_GSCOPE_FLAG_UNUSED,
+	THREAD_GSCOPE_FLAG_USED, THREAD_GSCOPE_FLAG_WAIT,
+	THREAD_GSCOPE_RESET_FLAG, THREAD_GSCOPE_SET_FLAG,
+	THREAD_GSCOPE_WAIT): Define.
+	* sysdeps/sparc/tls.h (THREAD_GSCOPE_FLAG_UNUSED,
+	THREAD_GSCOPE_FLAG_USED, THREAD_GSCOPE_FLAG_WAIT,
+	THREAD_GSCOPE_RESET_FLAG, THREAD_GSCOPE_SET_FLAG,
+	THREAD_GSCOPE_WAIT): Define.
+	* sysdeps/sh/tls.h (THREAD_GSCOPE_FLAG_UNUSED,
+	THREAD_GSCOPE_FLAG_USED, THREAD_GSCOPE_FLAG_WAIT,
+	THREAD_GSCOPE_RESET_FLAG, THREAD_GSCOPE_SET_FLAG,
+	THREAD_GSCOPE_WAIT): Define.
+	* sysdeps/ia64/tls.h (THREAD_GSCOPE_FLAG_UNUSED,
+	THREAD_GSCOPE_FLAG_USED, THREAD_GSCOPE_FLAG_WAIT,
+	THREAD_GSCOPE_RESET_FLAG, THREAD_GSCOPE_SET_FLAG,
+	THREAD_GSCOPE_WAIT): Define.
+
+2007-05-24  Richard Henderson  <rth@redhat.com>
+
+	* descr.h (struct pthread): Add header.gscope_flag.
+	* sysdeps/alpha/tls.h (THREAD_GSCOPE_FLAG_UNUSED,
+	THREAD_GSCOPE_FLAG_USED, THREAD_GSCOPE_FLAG_WAIT,
+	THREAD_GSCOPE_RESET_FLAG, THREAD_GSCOPE_SET_FLAG,
+	THREAD_GSCOPE_WAIT): Define.
+
+2007-05-26  Ulrich Drepper  <drepper@redhat.com>
+
+	* allocatestack.c: Revert last change.
+	* init.c: Likewise.
+	* sysdeps/i386/tls.h: Likewise.
+	* sysdeps/x86_64/tls.h: Likewise.
+
+2007-05-24  Jakub Jelinek  <jakub@redhat.com>
+
+	* sysdeps/powerpc/tls.h (tcbhead_t): Add gscope_flag.
+	(THREAD_GSCOPE_FLAG_UNUSED, THREAD_GSCOPE_FLAG_USED,
+	THREAD_GSCOPE_FLAG_WAIT): Define.
+	(THREAD_GSCOPE_GET_FLAG, THREAD_GSCOPE_SET_FLAG,
+	THREAD_GSCOPE_RESET_FLAG, THREAD_GSCOPE_WAIT): Define.
+	* sysdeps/i386/tls.h (THREAD_GSCOPE_WAIT): Don't use
+	PTR_DEMANGLE.
+	(THREAD_GSCOPE_GET_FLAG): Define.
+	* sysdeps/x86_64/tls.h (THREAD_GSCOPE_GET_FLAG): Define.
+	* allocatestack.c (__wait_lookup_done): Use THREAD_GSCOPE_GET_FLAG
+	instead of ->header.gscope_flag directly.
+
+2007-05-21  Ulrich Drepper  <drepper@redhat.com>
+
+	* sysdeps/pthread/pthread-functions.h (struct pthread_functions):
+	Remove ptr_wait_lookup_done again.
+	* init.c (pthread_functions): Don't add .ptr_wait_lookup_done here.
+	(__pthread_initialize_minimal_internal): Initialize
+	_dl_wait_lookup_done pointer in _rtld_global directly.
+	* sysdeps/unix/sysv/linux/libc_pthread_init.c (__libc_pthread_init):
+	Remove code to code _dl_wait_lookup_done.
+	* sysdeps/x86_64/tls.h (THREAD_GSCOPE_WAIT): The pointer is not
+	encrypted for now.
+
+2007-05-19  Ulrich Drepper  <drepper@redhat.com>
+
+	* allocatestack.c (__wait_lookup_done): New function.
+	* sysdeps/pthread/pthread-functions.h (struct pthread_functions):
+	Add ptr_wait_lookup_done.
+	* init.c (pthread_functions): Initialize .ptr_wait_lookup_done.
+	* pthreadP.h: Declare __wait_lookup_done.
+	* sysdeps/i386/tls.h (tcbhead_t): Add gscope_flag.
+	Define macros to implement reference handling of global scope.
+	* sysdeps/x86_64/tls.h: Likewise.
+	* sysdeps/unix/sysv/linux/libc_pthread_init.c (__libc_pthread_init):
+	Initialize GL(dl_wait_lookup_done).
+
 2007-05-25  Ulrich Drepper  <drepper@redhat.com>
 
 	* Makefile (tests): Add tst-sem10.
@@ -16,12 +101,6 @@
 	* tst-robust9.c (do_test): Don't fail if ENABLE_PI and
 	pthread_mutex_init failed with ENOTSUP.
 
-2007-01-15  Jakub Jelinek  <jakub@redhat.com>
-
-	* pthread_create.c (__pthread_create_2_1): On the first pthread_create
-	in a process make sure main search list can store at least 256
-	entries.
-
 2007-05-17  Ulrich Drepper  <drepper@redhat.com>
 
 	[BZ #4512]
diff --git a/nptl/allocatestack.c b/nptl/allocatestack.c
index 6b60642042..e556dbac08 100644
--- a/nptl/allocatestack.c
+++ b/nptl/allocatestack.c
@@ -996,3 +996,60 @@ __pthread_init_static_tls (struct link_map *map)
 
   lll_unlock (stack_cache_lock);
 }
+
+
+void
+attribute_hidden
+__wait_lookup_done (void)
+{
+  lll_lock (stack_cache_lock);
+
+  struct pthread *self = THREAD_SELF;
+
+  /* Iterate over the list with system-allocated threads first.  */
+  list_t *runp;
+  list_for_each (runp, &stack_used)
+    {
+      struct pthread *t = list_entry (runp, struct pthread, list);
+      if (t == self || t->header.gscope_flag == THREAD_GSCOPE_FLAG_UNUSED)
+	continue;
+
+      int *const gscope_flagp = &t->header.gscope_flag;
+
+      /* We have to wait until this thread is done with the global
+	 scope.  First tell the thread that we are waiting and
+	 possibly have to be woken.  */
+      if (atomic_compare_and_exchange_bool_acq (gscope_flagp,
+						THREAD_GSCOPE_FLAG_WAIT,
+						THREAD_GSCOPE_FLAG_USED))
+	continue;
+
+      do
+	lll_futex_wait (gscope_flagp, THREAD_GSCOPE_FLAG_WAIT);
+      while (*gscope_flagp == THREAD_GSCOPE_FLAG_WAIT);
+    }
+
+  /* Now the list with threads using user-allocated stacks.  */
+  list_for_each (runp, &__stack_user)
+    {
+      struct pthread *t = list_entry (runp, struct pthread, list);
+      if (t == self || t->header.gscope_flag == THREAD_GSCOPE_FLAG_UNUSED)
+	continue;
+
+      int *const gscope_flagp = &t->header.gscope_flag;
+
+      /* We have to wait until this thread is done with the global
+	 scope.  First tell the thread that we are waiting and
+	 possibly have to be woken.  */
+      if (atomic_compare_and_exchange_bool_acq (gscope_flagp,
+						THREAD_GSCOPE_FLAG_WAIT,
+						THREAD_GSCOPE_FLAG_USED))
+	continue;
+
+      do
+	lll_futex_wait (gscope_flagp, THREAD_GSCOPE_FLAG_WAIT);
+      while (*gscope_flagp == THREAD_GSCOPE_FLAG_WAIT);
+    }
+
+  lll_unlock (stack_cache_lock);
+}
diff --git a/nptl/descr.h b/nptl/descr.h
index 00cad1aa83..74d8c44140 100644
--- a/nptl/descr.h
+++ b/nptl/descr.h
@@ -131,6 +131,7 @@ struct pthread
     struct
     {
       int multiple_threads;
+      int gscope_flag;
     } header;
 #endif
 
diff --git a/nptl/init.c b/nptl/init.c
index dddc975a5e..827e795c2d 100644
--- a/nptl/init.c
+++ b/nptl/init.c
@@ -386,6 +386,8 @@ __pthread_initialize_minimal_internal (void)
 
   GL(dl_init_static_tls) = &__pthread_init_static_tls;
 
+  GL(dl_wait_lookup_done) = &__wait_lookup_done;
+
   /* Register the fork generation counter with the libc.  */
 #ifndef TLS_MULTIPLE_THREADS_IN_TCB
   __libc_multiple_threads_ptr =
diff --git a/nptl/pthreadP.h b/nptl/pthreadP.h
index f9634ab0ff..f560f72e4e 100644
--- a/nptl/pthreadP.h
+++ b/nptl/pthreadP.h
@@ -545,6 +545,8 @@ extern int __nptl_setxid (struct xid_command *cmdp) attribute_hidden;
 
 extern void __free_stack_cache (void) attribute_hidden;
 
+extern void __wait_lookup_done (void) attribute_hidden;
+
 #ifdef SHARED
 # define PTHREAD_STATIC_FN_REQUIRE(name)
 #else
diff --git a/nptl/pthread_create.c b/nptl/pthread_create.c
index 22e8f01804..79729ced03 100644
--- a/nptl/pthread_create.c
+++ b/nptl/pthread_create.c
@@ -462,30 +462,6 @@ __pthread_create_2_1 (newthread, attr, start_routine, arg)
   pd->flags = ((iattr->flags & ~(ATTR_FLAG_SCHED_SET | ATTR_FLAG_POLICY_SET))
 	       | (self->flags & (ATTR_FLAG_SCHED_SET | ATTR_FLAG_POLICY_SET)));
 
-  /* Hack: realloc the main search list on the first pthread_create call
-     to minimize the number of global search scope reallocations.
-     Wastes at most 1KB on 32-bit and 2KB on 64-bit per process
-     which calls pthread_create.  */
-  if (__builtin_expect (self->header.multiple_threads == 0, 0)
-      && GL(dl_ns)[0]._ns_main_searchlist
-      && GL(dl_ns)[0]._ns_main_searchlist->r_nlist < 256
-      && GL(dl_ns)[0]._ns_global_scope_alloc < 256)
-    {
-      struct link_map **new_global = (struct link_map **)
-	realloc (GL(dl_ns)[0]._ns_global_scope_alloc == 0
-		 ? NULL : GL(dl_ns)[0]._ns_main_searchlist->r_list,
-		 256 * sizeof (struct link_map *));
-      if (new_global != NULL)
-	{
-	  if (GL(dl_ns)[0]._ns_global_scope_alloc == 0)
-	    memcpy (new_global, GL(dl_ns)[0]._ns_main_searchlist->r_list,
-		    GL(dl_ns)[0]._ns_main_searchlist->r_nlist
-		    * sizeof (struct link_map *));
-	  GL(dl_ns)[0]._ns_global_scope_alloc = 256;
-	  GL(dl_ns)[0]._ns_main_searchlist->r_list = new_global;
-	}
-    }
-
   /* Initialize the field for the ID of the thread which is waiting
      for us.  This is a self-reference in case the thread is created
      detached.  */
diff --git a/nptl/sysdeps/alpha/tls.h b/nptl/sysdeps/alpha/tls.h
index be2430f676..9072e2d6fb 100644
--- a/nptl/sysdeps/alpha/tls.h
+++ b/nptl/sysdeps/alpha/tls.h
@@ -121,6 +121,29 @@ typedef struct
 #define THREAD_SETMEM_NC(descr, member, idx, value) \
   descr->member[idx] = (value)
 
+/* Get and set the global scope generation counter in struct pthread.  */
+#define THREAD_GSCOPE_FLAG_UNUSED 0
+#define THREAD_GSCOPE_FLAG_USED   1
+#define THREAD_GSCOPE_FLAG_WAIT   2
+#define THREAD_GSCOPE_RESET_FLAG() \
+  do									     \
+    { int __res								     \
+	= atomic_exchange_rel (&THREAD_SELF->header.gscope_flag,	     \
+			       THREAD_GSCOPE_FLAG_UNUSED);		     \
+      if (__res == THREAD_GSCOPE_FLAG_WAIT)				     \
+	lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1);		     \
+    }									     \
+  while (0)
+#define THREAD_GSCOPE_SET_FLAG() \
+  do									     \
+    {									     \
+      THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED;	     \
+      atomic_write_barrier ();						     \
+    }									     \
+  while (0)
+#define THREAD_GSCOPE_WAIT() \
+  GL(dl_wait_lookup_done) ()
+
 #endif /* __ASSEMBLER__ */
 
 #endif	/* tls.h */
diff --git a/nptl/sysdeps/i386/tls.h b/nptl/sysdeps/i386/tls.h
index d5b3797e69..7c80cd7d14 100644
--- a/nptl/sysdeps/i386/tls.h
+++ b/nptl/sysdeps/i386/tls.h
@@ -51,6 +51,7 @@ typedef struct
   uintptr_t sysinfo;
   uintptr_t stack_guard;
   uintptr_t pointer_guard;
+  int gscope_flag;
 } tcbhead_t;
 
 # define TLS_MULTIPLE_THREADS_IN_TCB 1
@@ -431,6 +432,26 @@ union user_desc_init
    = THREAD_GETMEM (THREAD_SELF, header.pointer_guard))
 
 
+/* Get and set the global scope generation counter in the TCB head.  */
+#define THREAD_GSCOPE_FLAG_UNUSED 0
+#define THREAD_GSCOPE_FLAG_USED   1
+#define THREAD_GSCOPE_FLAG_WAIT   2
+#define THREAD_GSCOPE_RESET_FLAG() \
+  do									      \
+    { int __res;							      \
+      asm volatile ("xchgl %0, %%gs:%P1"				      \
+		    : "=r" (__res)					      \
+		    : "i" (offsetof (struct pthread, header.gscope_flag)),    \
+		      "0" (THREAD_GSCOPE_FLAG_UNUSED));			      \
+      if (__res == THREAD_GSCOPE_FLAG_WAIT)				      \
+	lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1);		      \
+    }									      \
+  while (0)
+#define THREAD_GSCOPE_SET_FLAG() \
+  THREAD_SETMEM (THREAD_SELF, header.gscope_flag, THREAD_GSCOPE_FLAG_USED)
+#define THREAD_GSCOPE_WAIT() \
+  GL(dl_wait_lookup_done) ()
+
 #endif /* __ASSEMBLER__ */
 
 #endif	/* tls.h */
diff --git a/nptl/sysdeps/ia64/tls.h b/nptl/sysdeps/ia64/tls.h
index 22a8b08144..4270723b9a 100644
--- a/nptl/sysdeps/ia64/tls.h
+++ b/nptl/sysdeps/ia64/tls.h
@@ -163,6 +163,29 @@ register struct pthread *__thread_self __asm__("r13");
   (((uintptr_t *) ((char *) (descr) + TLS_PRE_TCB_SIZE))[-2] \
    = THREAD_GET_POINTER_GUARD ())
 
+/* Get and set the global scope generation counter in struct pthread.  */
+#define THREAD_GSCOPE_FLAG_UNUSED 0
+#define THREAD_GSCOPE_FLAG_USED   1
+#define THREAD_GSCOPE_FLAG_WAIT   2
+#define THREAD_GSCOPE_RESET_FLAG() \
+  do									     \
+    { int __res								     \
+	= atomic_exchange_rel (&THREAD_SELF->header.gscope_flag,	     \
+			       THREAD_GSCOPE_FLAG_UNUSED);		     \
+      if (__res == THREAD_GSCOPE_FLAG_WAIT)				     \
+	lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1);		     \
+    }									     \
+  while (0)
+#define THREAD_GSCOPE_SET_FLAG() \
+  do									     \
+    {									     \
+      THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED;	     \
+      atomic_write_barrier ();						     \
+    }									     \
+  while (0)
+#define THREAD_GSCOPE_WAIT() \
+  GL(dl_wait_lookup_done) ()
+
 #endif /* __ASSEMBLER__ */
 
 #endif	/* tls.h */
diff --git a/nptl/sysdeps/powerpc/tls.h b/nptl/sysdeps/powerpc/tls.h
index ddaafe23d0..de822833f9 100644
--- a/nptl/sysdeps/powerpc/tls.h
+++ b/nptl/sysdeps/powerpc/tls.h
@@ -180,6 +180,29 @@ register void *__thread_register __asm__ ("r13");
    different value to mean unset l_tls_offset.  */
 # define NO_TLS_OFFSET		-1
 
+/* Get and set the global scope generation counter in struct pthread.  */
+#define THREAD_GSCOPE_FLAG_UNUSED 0
+#define THREAD_GSCOPE_FLAG_USED   1
+#define THREAD_GSCOPE_FLAG_WAIT   2
+#define THREAD_GSCOPE_RESET_FLAG() \
+  do									     \
+    { int __res								     \
+	= atomic_exchange_rel (&THREAD_SELF->header.gscope_flag,	     \
+			       THREAD_GSCOPE_FLAG_UNUSED);		     \
+      if (__res == THREAD_GSCOPE_FLAG_WAIT)				     \
+	lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1);		     \
+    }									     \
+  while (0)
+#define THREAD_GSCOPE_SET_FLAG() \
+  do									     \
+    {									     \
+      THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED;	     \
+      atomic_write_barrier ();						     \
+    }									     \
+  while (0)
+#define THREAD_GSCOPE_WAIT() \
+  GL(dl_wait_lookup_done) ()
+
 #endif /* __ASSEMBLER__ */
 
 #endif	/* tls.h */
diff --git a/nptl/sysdeps/s390/tls.h b/nptl/sysdeps/s390/tls.h
index 6f6f17b975..1c86a19676 100644
--- a/nptl/sysdeps/s390/tls.h
+++ b/nptl/sysdeps/s390/tls.h
@@ -50,6 +50,7 @@ typedef struct
   int multiple_threads;
   uintptr_t sysinfo;
   uintptr_t stack_guard;
+  int gscope_flag;
 } tcbhead_t;
 
 # ifndef __s390x__
@@ -168,6 +169,29 @@ typedef struct
 #define THREAD_SET_POINTER_GUARD(value)
 #define THREAD_COPY_POINTER_GUARD(descr)
 
+/* Get and set the global scope generation counter in struct pthread.  */
+#define THREAD_GSCOPE_FLAG_UNUSED 0
+#define THREAD_GSCOPE_FLAG_USED   1
+#define THREAD_GSCOPE_FLAG_WAIT   2
+#define THREAD_GSCOPE_RESET_FLAG() \
+  do									     \
+    { int __res								     \
+	= atomic_exchange_rel (&THREAD_SELF->header.gscope_flag,	     \
+			       THREAD_GSCOPE_FLAG_UNUSED);		     \
+      if (__res == THREAD_GSCOPE_FLAG_WAIT)				     \
+	lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1);		     \
+    }									     \
+  while (0)
+#define THREAD_GSCOPE_SET_FLAG() \
+  do									     \
+    {									     \
+      THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED;	     \
+      atomic_write_barrier ();						     \
+    }									     \
+  while (0)
+#define THREAD_GSCOPE_WAIT() \
+  GL(dl_wait_lookup_done) ()
+
 #endif /* __ASSEMBLER__ */
 
 #endif	/* tls.h */
diff --git a/nptl/sysdeps/sh/tls.h b/nptl/sysdeps/sh/tls.h
index d9aa1073b8..09522189a6 100644
--- a/nptl/sysdeps/sh/tls.h
+++ b/nptl/sysdeps/sh/tls.h
@@ -150,6 +150,29 @@ typedef struct
      __asm __volatile ("stc gbr,%0" : "=r" (__tcbp));			      \
      ((tcbhead_t *) (descr + 1))->pointer_guard	= __tcbp->pointer_guard;})
 
+/* Get and set the global scope generation counter in struct pthread.  */
+#define THREAD_GSCOPE_FLAG_UNUSED 0
+#define THREAD_GSCOPE_FLAG_USED   1
+#define THREAD_GSCOPE_FLAG_WAIT   2
+#define THREAD_GSCOPE_RESET_FLAG() \
+  do									     \
+    { int __res								     \
+	= atomic_exchange_rel (&THREAD_SELF->header.gscope_flag,	     \
+			       THREAD_GSCOPE_FLAG_UNUSED);		     \
+      if (__res == THREAD_GSCOPE_FLAG_WAIT)				     \
+	lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1);		     \
+    }									     \
+  while (0)
+#define THREAD_GSCOPE_SET_FLAG() \
+  do									     \
+    {									     \
+      THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED;	     \
+      atomic_write_barrier ();						     \
+    }									     \
+  while (0)
+#define THREAD_GSCOPE_WAIT() \
+  GL(dl_wait_lookup_done) ()
+
 #endif /* __ASSEMBLER__ */
 
 #endif	/* tls.h */
diff --git a/nptl/sysdeps/sparc/tls.h b/nptl/sysdeps/sparc/tls.h
index 4fbe426595..8a0c930b3e 100644
--- a/nptl/sysdeps/sparc/tls.h
+++ b/nptl/sysdeps/sparc/tls.h
@@ -141,6 +141,29 @@ register struct pthread *__thread_self __asm__("%g7");
 # define THREAD_COPY_POINTER_GUARD(descr) \
   ((descr)->header.pointer_guard = THREAD_GET_POINTER_GUARD ())
 
+/* Get and set the global scope generation counter in struct pthread.  */
+#define THREAD_GSCOPE_FLAG_UNUSED 0
+#define THREAD_GSCOPE_FLAG_USED   1
+#define THREAD_GSCOPE_FLAG_WAIT   2
+#define THREAD_GSCOPE_RESET_FLAG() \
+  do									     \
+    { int __res								     \
+	= atomic_exchange_rel (&THREAD_SELF->header.gscope_flag,	     \
+			       THREAD_GSCOPE_FLAG_UNUSED);		     \
+      if (__res == THREAD_GSCOPE_FLAG_WAIT)				     \
+	lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1);		     \
+    }									     \
+  while (0)
+#define THREAD_GSCOPE_SET_FLAG() \
+  do									     \
+    {									     \
+      THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED;	     \
+      atomic_write_barrier ();						     \
+    }									     \
+  while (0)
+#define THREAD_GSCOPE_WAIT() \
+  GL(dl_wait_lookup_done) ()
+
 #endif /* !ASSEMBLER */
 
 #endif	/* tls.h */
diff --git a/nptl/sysdeps/x86_64/tls.h b/nptl/sysdeps/x86_64/tls.h
index 0b5aeb00ff..4a614c02af 100644
--- a/nptl/sysdeps/x86_64/tls.h
+++ b/nptl/sysdeps/x86_64/tls.h
@@ -47,6 +47,7 @@ typedef struct
   dtv_t *dtv;
   void *self;		/* Pointer to the thread descriptor.  */
   int multiple_threads;
+  int gscope_flag;
   uintptr_t sysinfo;
   uintptr_t stack_guard;
   uintptr_t pointer_guard;
@@ -337,6 +338,26 @@ typedef struct
    = THREAD_GETMEM (THREAD_SELF, header.pointer_guard))
 
 
+/* Get and set the global scope generation counter in the TCB head.  */
+#define THREAD_GSCOPE_FLAG_UNUSED 0
+#define THREAD_GSCOPE_FLAG_USED   1
+#define THREAD_GSCOPE_FLAG_WAIT   2
+#define THREAD_GSCOPE_RESET_FLAG() \
+  do									      \
+    { int __res;							      \
+      asm volatile ("xchgl %0, %%fs:%P1"				      \
+		    : "=r" (__res)					      \
+		    : "i" (offsetof (struct pthread, header.gscope_flag)),    \
+		      "0" (THREAD_GSCOPE_FLAG_UNUSED));			      \
+      if (__res == THREAD_GSCOPE_FLAG_WAIT)				      \
+	lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1);		      \
+    }									      \
+  while (0)
+#define THREAD_GSCOPE_SET_FLAG() \
+  THREAD_SETMEM (THREAD_SELF, header.gscope_flag, THREAD_GSCOPE_FLAG_USED)
+#define THREAD_GSCOPE_WAIT() \
+  GL(dl_wait_lookup_done) ()
+
 #endif /* __ASSEMBLER__ */
 
 #endif	/* tls.h */