Update.

1998-08-26 15:46  Ulrich Drepper  <drepper@cygnus.com>

	* internals.h: Define THREAD_GETMEM and THREAD_SETMEM to default if
	not already defined.
	(struct _pthread_descr_struct): Add p_self and p_nr field.
	* manager.c (__pthread_handles): Define second element to point
	to manager thread.
	(__pthread_handles_num): Initialize to 2.
	(__pthread_manager): Use INIT_THREAD_SELF with two arguments.
	(pthread_start_thread): Likewise.
	(pthread_handle_create): Start search for free slot at entry 2.
	Initialize new fields p_self and p_nr.
	Call __clone with CLONE_PTRACE if available.
	(pthread_free): Call FREE_THREAD_SELF if available.
	* pthread.c (__pthread_initial_thread): Initialize new fields.
	(__pthread_manager_thread): Likewise.
	(__pthread_initialize_manager): Call __clone with CLONE_PTRACE.

	* cancel.c: Use THREAD_GETMEM and THREAD_SETMEM to access the
	elements of the thread descriptor.
	* condvar.c: Likewise.
	* errno.c: Likewise.
	* join.c: Likewise.
	* manager.c: Likewise.
	* pthread.c: Likewise.
	* ptlongjmp.c: Likewise.
	* semaphore.c: Likewise.
	* signals.c: Likewise.
	* specific.c: Likewise.
	* spinlock.c: Likewise.

	* sysdeps/alpha/pt-machine.h (INIT_THREAD_SELF): Add extra parameter.

	* sysdeps/i386/useldt.h: New file.
	* sysdeps/i386/i686/pt-machine.h: Show how to use this file.

	* sysdeps/sparc/sparc32/pt-machine.h: Define THREAD_GETMEM and
	THREAD_SETMEM using __thread_self.
	* sysdeps/sparc/sparc64/pt-machine.h: Likewise.

2 files changed, 128 insertions, 0 deletions

diff --git a/linuxthreads/sysdeps/i386/i686/pt-machine.h b/linuxthreads/sysdeps/i386/i686/pt-machine.h
index bb0f0bc8e1..a4b3a63f1c 100644
--- a/linuxthreads/sysdeps/i386/i686/pt-machine.h
+++ b/linuxthreads/sysdeps/i386/i686/pt-machine.h
@@ -70,3 +70,7 @@ set_eflags (int newflags)
 {
   __asm__ __volatile__ ("pushl %0; popfl" : : "r" (newflags) : "cc");
 }
+
+
+/* Use the LDT implementation only if the kernel is fixed.  */
+//#include "../useldt.h"
diff --git a/linuxthreads/sysdeps/i386/useldt.h b/linuxthreads/sysdeps/i386/useldt.h
new file mode 100644
index 0000000000..2fdc0ce767
--- /dev/null
+++ b/linuxthreads/sysdeps/i386/useldt.h
@@ -0,0 +1,124 @@
+/* Special definitions for ix86 machine using segment register based
+   thread descriptor.
+   Copyright (C) 1998 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@cygnus.com>.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <stddef.h>	/* For offsetof.  */
+
+
+/* We don't want to include the kernel header.  So duplicate the
+   information.  */
+
+/* Structure passed on `modify_ldt' call.  */
+struct modify_ldt_ldt_s
+{
+  unsigned int entry_number;
+  unsigned long int base_addr;
+  unsigned int limit;
+  unsigned int seg_32bit:1;
+  unsigned int contents:2;
+  unsigned int read_exec_only:1;
+  unsigned int limit_in_pages:1;
+  unsigned int seg_not_present:1;
+  unsigned int useable:1;
+  unsigned int empty:25;
+};
+
+/* System call to set LDT entry.  */
+extern int __modify_ldt (int, struct modify_ldt_ldt_s *, size_t);
+
+
+/* Return the thread descriptor for the current thread.
+
+   The contained asm must *not* be marked volatile since otherwise
+   assignments like
+	pthread_descr self = thread_self();
+   do not get optimized away.  */
+#define THREAD_SELF \
+({									      \
+  register pthread_descr __self;					      \
+  __asm__ ("movl %%gs:%c1,%0" : "=r" (__self)				      \
+	   : "i" (offsetof (struct _pthread_descr_struct, p_self)));	      \
+  __self;								      \
+})
+
+/* Initialize the thread-unique value.  */
+#define INIT_THREAD_SELF(descr, nr) \
+{									      \
+  struct modify_ldt_ldt_s ldt_entry =					      \
+    { nr, (unsigned long int) descr, sizeof (*descr), 1, 0, 0, 0, 0, 1, 0 };  \
+  if (__modify_ldt (1, &ldt_entry, sizeof (ldt_entry)) != 0)		      \
+    abort ();								      \
+  __asm__ __volatile__ ("movw %w0, %%gs" : : "r" (nr * 8 + 7));		      \
+}
+
+/* Free resources associated with thread descriptor.  */
+#define FREE_THREAD_SELF(descr, nr) \
+{									      \
+  struct modify_ldt_ldt_s ldt_entry =					      \
+    { nr, 0, 0, 0, 0, 1, 0, 1, 0, 0 };					      \
+  __asm__ __volatile__ ("movw %w0,%%gs" : : "r" (0));			      \
+  __modify_ldt (1, &ldt_entry, sizeof (ldt_entry));			      \
+}
+
+/* Read member of the thread descriptor directly.  */
+#define THREAD_GETMEM(descr, member) \
+({									      \
+  __typeof__ (descr->member) __value;					      \
+  if (sizeof (__value) == 1)						      \
+    __asm__ __volatile__ ("movb %%gs:%c1,%b0"				      \
+			  : "=r" (__value)				      \
+			  : "0" (0),					      \
+			    "i" (offsetof (struct _pthread_descr_struct,      \
+					   member)));			      \
+  else									      \
+    {									      \
+      if (sizeof (__value) != 4)					      \
+	/* There should not be any value with a size other than 1 or 4.  */   \
+	abort ();							      \
+									      \
+      __asm__ __volatile__ ("movl %%gs:%c1,%0"				      \
+			    : "=r" (__value)				      \
+			    : "i" (offsetof (struct _pthread_descr_struct,    \
+					     member)));			      \
+    }									      \
+  __value;								      \
+})
+
+/* Set member of the thread descriptor directly.  */
+#define THREAD_SETMEM(descr, member, value) \
+({									      \
+  __typeof__ (descr->member) __value = (value);				      \
+  if (sizeof (__value) == 1)						      \
+    __asm__ __volatile__ ("movb %0,%%gs:%c1" :				      \
+			  : "r" (__value),				      \
+			    "i" (offsetof (struct _pthread_descr_struct,      \
+					   member)));			      \
+  else									      \
+    {									      \
+      if (sizeof (__value) != 4)					      \
+	/* There should not be any value with a size other than 1 or 4.  */   \
+	abort ();							      \
+									      \
+      __asm__ __volatile__ ("movl %0,%%gs:%c1" :			      \
+			    : "r" (__value),				      \
+			      "i" (offsetof (struct _pthread_descr_struct,    \
+					     member)));			      \
+    }									      \
+})