[PATCH] global scope locking for ppc/ppc64

[Jakub Jelinek <jakub at redhat dot com>]

Hi!

On ppc* (and I vaguely remember other arches) tcbhead_t
is not inside of struct pthread, so making ppc compile
needs some generic changes.  The following patch introduces
new THREAD_GSCOPE_GET_FLAG macro, so that gscope_flag field
can live outside of struct pthread.

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.

--- libc/nptl/sysdeps/powerpc/tls.h.jj	2006-11-28 11:25:16.000000000 +0100
+++ libc/nptl/sysdeps/powerpc/tls.h	2007-05-24 18:54:03.000000000 +0200
@@ -1,5 +1,5 @@
 /* Definition for thread-local data handling.  NPTL/PowerPC version.
-   Copyright (C) 2003, 2005, 2006 Free Software Foundation, Inc.
+   Copyright (C) 2003, 2005, 2006, 2007 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
@@ -63,10 +63,11 @@ typedef union dtv
 # include <nptl/descr.h>
 
 /* The stack_guard is accessed directly by GCC -fstack-protector code,
-   so it is a part of public ABI.  The dtv and pointer_guard fields
-   are private.  */
+   so it is a part of public ABI.  The dtv, pointer_guard and gscope_flag
+   fields are private.  */
 typedef struct
 {
+  int gscope_flag;
   uintptr_t pointer_guard;
   uintptr_t stack_guard;
   dtv_t *dtv;
@@ -180,6 +181,27 @@ register void *__thread_register __asm__
    different value to mean unset l_tls_offset.  */
 # define NO_TLS_OFFSET		-1
 
+/* 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_GET_FLAG(descr) \
+  (((tcbhead_t *) ((char *) (descr)					     \
+		   + TLS_PRE_TCB_SIZE))[-1].gscope_flag)
+#define THREAD_GSCOPE_RESET_FLAG() \
+  do									     \
+    { int __res								     \
+	= atomic_exchange_rel (&THREAD_GSCOPE_GET_FLAG (THREAD_SELF),	     \
+			       THREAD_GSCOPE_FLAG_UNUSED);		     \
+      if (__res == THREAD_GSCOPE_FLAG_WAIT)				     \
+	lll_futex_wake (&THREAD_GSCOPE_GET_FLAG (THREAD_SELF), 1);	     \
+    }									     \
+  while (0)
+#define THREAD_GSCOPE_SET_FLAG() \
+  (THREAD_GSCOPE_GET_FLAG (THREAD_SELF) = THREAD_GSCOPE_FLAG_USED)
+#define THREAD_GSCOPE_WAIT() \
+  GL(dl_wait_lookup_done) ()
+
 #endif /* __ASSEMBLER__ */
 
 #endif	/* tls.h */
--- libc/nptl/sysdeps/i386/tls.h.jj	2007-05-24 16:41:06.000000000 +0200
+++ libc/nptl/sysdeps/i386/tls.h	2007-05-24 17:53:37.000000000 +0200
@@ -454,16 +454,9 @@ union user_desc_init
   while (0)
 #define THREAD_GSCOPE_SET_FLAG() \
   THREAD_SETMEM (THREAD_SELF, header.gscope_flag, THREAD_GSCOPE_FLAG_USED)
-#ifdef PTR_DEMANGLE
-# define THREAD_GSCOPE_WAIT() \
-  do { void (*ptr) (void) = GL(dl_wait_lookup_done);			      \
-       PTR_DEMANGLE (ptr);						      \
-       ptr ();								      \
-  } while (0)
-#else
-# define THREAD_GSCOPE_WAIT() \
+#define THREAD_GSCOPE_GET_FLAG(descr) (descr)->header.gscope_flag
+#define THREAD_GSCOPE_WAIT() \
   GL(dl_wait_lookup_done) ()
-#endif
 
 
 #endif /* __ASSEMBLER__ */
--- libc/nptl/sysdeps/x86_64/tls.h.jj	2007-05-24 16:41:08.000000000 +0200
+++ libc/nptl/sysdeps/x86_64/tls.h	2007-05-24 17:53:58.000000000 +0200
@@ -360,6 +360,7 @@ typedef struct
   while (0)
 #define THREAD_GSCOPE_SET_FLAG() \
   THREAD_SETMEM (THREAD_SELF, header.gscope_flag, THREAD_GSCOPE_FLAG_USED)
+#define THREAD_GSCOPE_GET_FLAG(descr) (descr)->header.gscope_flag
 #define THREAD_GSCOPE_WAIT() \
   GL(dl_wait_lookup_done) ()
 
--- libc/nptl/allocatestack.c.jj	2007-05-24 16:41:06.000000000 +0200
+++ libc/nptl/allocatestack.c	2007-05-24 18:01:04.000000000 +0200
@@ -1023,10 +1023,10 @@ __wait_lookup_done (void)
   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)
+      if (t == self || THREAD_GSCOPE_GET_FLAG (t) == THREAD_GSCOPE_FLAG_UNUSED)
 	continue;
 
-      int *const gscope_flagp = &t->header.gscope_flag;
+      int *const gscope_flagp = &THREAD_GSCOPE_GET_FLAG (t);
 
       /* We have to wait until this thread is done with the global
 	 scope.  First tell the thread that we are waiting and
@@ -1045,10 +1045,10 @@ __wait_lookup_done (void)
   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)
+      if (t == self || THREAD_GSCOPE_GET_FLAG (t) == THREAD_GSCOPE_FLAG_UNUSED)
 	continue;
 
-      int *const gscope_flagp = &t->header.gscope_flag;
+      int *const gscope_flagp = &THREAD_GSCOPE_GET_FLAG (t);
 
       /* We have to wait until this thread is done with the global
 	 scope.  First tell the thread that we are waiting and

	Jakub