Update.

2002-12-12  Ulrich Drepper  <drepper@redhat.com>

	* sysdeps/unix/sysv/linux/fork-gen.c: Renamed to...
	* sysdeps/unix/sysv/linux/libc_pthread_init.c: ...this.
	Initialize __libc_locking_needed.
	* init.c (__pthread_initialize_minimal): Call __libc_pthread_init
	instead of __register_pthread_fork_handler.
	* sysdeps/pthread/bits/libc-lock.h: Declare __libc_locking_needed.
	* sysdeps/unix/sysv/linux/Makefile (sysdep_routimes): Replace
	fork-gen with libc_pthread_init.
	* sysdeps/unix/sysv/linux/Versions: Use __libc_pthread_init instead
	of __register_pthread_fork_handler.
	* sysdeps/unix/sysv/linux/fork.h: Declare __libc_pthread_init instead
	of __register_pthread_fork_handler.
	* sysdeps/unix/sysv/linux/i386/lowlevellock.h: Use
	__libc_locking_needed to determine whether lock prefix can be avoided.
	* sysdeps/unix/sysv/linux/i386/i486/libc-lowlevellock.S: Likewise.

6 files changed, 256 insertions, 9 deletions

diff --git a/nptl/sysdeps/unix/sysv/linux/Makefile b/nptl/sysdeps/unix/sysv/linux/Makefile
index 9a84534d5b..c079a4013d 100644
--- a/nptl/sysdeps/unix/sysv/linux/Makefile
+++ b/nptl/sysdeps/unix/sysv/linux/Makefile
@@ -18,7 +18,7 @@
 # 02111-1307 USA.  */
 
 ifeq ($(subdir),nptl)
-sysdep_routines += register-atfork unregister-atfork fork-gen
+sysdep_routines += register-atfork unregister-atfork libc_pthread_init
 
 libpthread-sysdep_routines += pt-fork
 endif
diff --git a/nptl/sysdeps/unix/sysv/linux/Versions b/nptl/sysdeps/unix/sysv/linux/Versions
index 117598c95f..8fea097e43 100644
--- a/nptl/sysdeps/unix/sysv/linux/Versions
+++ b/nptl/sysdeps/unix/sysv/linux/Versions
@@ -1,6 +1,6 @@
 libc {
   GLIBC_PRIVATE {
-    __register_atfork; __register_pthread_fork_handler;
+    __register_atfork; __libc_pthread_init;
     __libc_current_sigrtmin_private; __libc_current_sigrtmax_private;
     __libc_allocate_rtsig_private;
   }
diff --git a/nptl/sysdeps/unix/sysv/linux/fork.h b/nptl/sysdeps/unix/sysv/linux/fork.h
index 85722a59eb..0bc283d1bc 100644
--- a/nptl/sysdeps/unix/sysv/linux/fork.h
+++ b/nptl/sysdeps/unix/sysv/linux/fork.h
@@ -56,5 +56,5 @@ extern int __register_atfork (void (*__prepare) (void),
 			      void *dso_handle);
 
 /* Register the generation counter in the libpthread with the libc.  */
-extern void __register_pthread_fork_handler (unsigned long int *__ptr,
-					     void (*reclaim) (void));
+extern void __libc_pthread_int (unsigned long int *__ptr,
+				void (*reclaim) (void));
diff --git a/nptl/sysdeps/unix/sysv/linux/i386/i486/libc-lowlevellock.S b/nptl/sysdeps/unix/sysv/linux/i386/i486/libc-lowlevellock.S
index 3ce1d6fe72..9a124ab0c2 100644
--- a/nptl/sysdeps/unix/sysv/linux/i386/i486/libc-lowlevellock.S
+++ b/nptl/sysdeps/unix/sysv/linux/i386/i486/libc-lowlevellock.S
@@ -1 +1,184 @@
-#include "lowlevellock.S"
+/* Copyright (C) 2002 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <sysdep.h>
+
+	.text
+
+#define SYS_gettimeofday	__NR_gettimeofday
+#define SYS_futex		240
+#define FUTEX_WAIT		0
+#define FUTEX_WAKE		1
+
+#define ETIMEDOUT               110
+
+
+	.globl	__lll_lock_wait
+	.type	__lll_lock_wait,@function
+	.hidden	__lll_lock_wait
+	.align	16
+__lll_lock_wait:
+	pushl	%esi
+	pushl	%ebx
+	pushl	%edx
+
+	movl	%ecx, %ebx
+	xorl	%esi, %esi	/* No timeout.  */
+	xorl	%ecx, %ecx	/* movl $FUTEX_WAIT, %ecx */
+1:
+	leal	-1(%eax), %edx	/* account for the preceeded xadd.  */
+	movl	$SYS_futex, %eax
+	int	$0x80
+
+	orl	$-1, %eax	/* Load -1.  */
+#ifndef UP
+	cmpl	$0, __libc_locking_needed
+	je,pt	0f
+	lock
+0:
+#endif
+	xaddl	%eax, (%ebx)
+	jne	1b
+
+	movl	$-1, (%ebx)
+
+	popl	%edx
+	popl	%ebx
+	popl	%esi
+	ret
+	.size	__lll_lock_wait,.-__lll_lock_wait
+
+
+	.globl	lll_unlock_wake_cb
+	.type	lll_unlock_wake_cb,@function
+	.hidden	lll_unlock_wake_cb
+	.align	16
+lll_unlock_wake_cb:
+	pushl	%esi
+	pushl	%ebx
+	pushl	%ecx
+	pushl	%edx
+
+	movl	20(%esp), %ebx
+#ifndef UP
+	cmpl	$0, __libc_locking_needed
+	je,pt	0f
+	lock
+0:
+#endif
+	incl	(%ebx)
+	jng	1f
+
+	popl	%edx
+	popl	%ecx
+	popl	%ebx
+	popl	%esi
+	ret
+	.size	lll_unlock_wake_cb,.-lll_unlock_wake_cb
+
+
+	.globl	__lll_unlock_wake
+	.type	__lll_unlock_wake,@function
+	.hidden	__lll_unlock_wake
+__lll_unlock_wake:
+	pushl	%esi
+	pushl	%ebx
+	pushl	%ecx
+	pushl	%edx
+
+	movl	%eax, %ebx
+1:	movl	$FUTEX_WAKE, %ecx
+	movl	$1, %edx	/* Wake one thread.  */
+	xorl	%esi, %esi
+	movl	%edx, (%ebx)	/* Stores '$1'.  */
+	movl	$SYS_futex, %eax
+	int	$0x80
+
+	popl	%edx
+	popl	%ecx
+	popl	%ebx
+	popl	%esi
+	ret
+	.size	__lll_unlock_wake,.-__lll_unlock_wake
+
+
+	.globl	__lll_timedwait_tid
+	.type	__lll_timedwait_tid,@function
+	.hidden	__lll_timedwait_tid
+__lll_timedwait_tid:
+	pushl	%edi
+	pushl	%esi
+	pushl	%ebx
+	pushl	%ebp
+
+	movl	%eax, %ebp
+	movl	%edx, %edi
+	subl	$8, %esp
+
+	/* Get current time.  */
+2:	movl	%esp, %ebx
+	xorl	%ecx, %ecx
+	movl	$SYS_gettimeofday, %eax
+	int	$0x80
+
+	/* Compute relative timeout.  */
+	movl	4(%esp), %eax
+	movl	$1000, %edx
+	mul	%edx		/* Milli seconds to nano seconds.  */
+	movl	(%edi), %ecx
+	movl	4(%edi), %edx
+	subl	(%esp), %ecx
+	subl	%eax, %edx
+	jns	5f
+	addl	$1000000000, %edx
+	decl	%ecx
+5:	testl	%ecx, %ecx
+	js	6f		/* Time is already up.  */
+
+	movl	%ecx, (%esp)	/* Store relative timeout.  */
+	movl	%edx, 4(%esp)
+
+	movl	(%ebp), %edx
+	testl	%edx, %edx
+	jz	4f
+
+	movl	%esp, %esi
+	xorl	%ecx, %ecx	/* movl $FUTEX_WAIT, %ecx */
+	movl	%ebp, %ebx
+	movl	$SYS_futex, %eax
+	int	$0x80
+
+	movl	%eax, %edx
+
+	cmpl	$0, (%ebx)
+	jne	1f
+4:	xorl	%eax, %eax
+
+3:	addl	$8, %esp
+	popl	%ebp
+	popl	%ebx
+	popl	%esi
+	popl	%edi
+	ret
+
+1:	cmpl	$-ETIMEDOUT, %edx
+	jne	2b
+6:	movl	$ETIMEDOUT, %eax
+	jmp	3b
+	.size	__lll_timedwait_tid,.-__lll_timedwait_tid
diff --git a/nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h b/nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h
index a3c02498f4..470dcf6108 100644
--- a/nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h
+++ b/nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h
@@ -139,7 +139,8 @@ extern int lll_unlock_wake_cb (int *__futex) attribute_hidden;
    <0  -  taken by more users */
 
 
-#define lll_trylock(futex) \
+#if defined NOT_IN_libc || defined UP
+# define lll_trylock(futex) \
   ({ unsigned char ret;							      \
      __asm __volatile (LOCK_INSTR "cmpxchgl %2, %1; setne %0"		      \
 		       : "=a" (ret), "=m" (futex)			      \
@@ -148,7 +149,7 @@ extern int lll_unlock_wake_cb (int *__futex) attribute_hidden;
      ret; })
 
 
-#define lll_lock(futex) \
+# define lll_lock(futex) \
   (void) ({ int ignore1, ignore2;					      \
 	    __asm __volatile (LOCK_INSTR "xaddl %0, %2\n\t"		      \
 			      "jne 1f\n\t"				      \
@@ -163,7 +164,7 @@ extern int lll_unlock_wake_cb (int *__futex) attribute_hidden;
 			      : "memory"); })
 
 
-#define lll_unlock(futex) \
+# define lll_unlock(futex) \
   (void) ({ int ignore;							      \
             __asm __volatile (LOCK_INSTR "incl %0\n\t"			      \
 			      "jng 1f\n\t"				      \
@@ -176,6 +177,59 @@ extern int lll_unlock_wake_cb (int *__futex) attribute_hidden;
 			      : "=m" (futex), "=&a" (ignore)		      \
 			      : "0" (futex)				      \
 			      : "memory"); })
+#else
+/* Special versions of the macros for use in libc itself.  They avoid
+   the lock prefix when the thread library is not used.
+
+   XXX In future we might even want to avoid it on UP machines.  */
+
+# define lll_trylock(futex) \
+  ({ unsigned char ret;							      \
+     __asm __volatile ("cmpl $0, __libc_locking_needed\n\t"		      \
+		       "je,pt 0f\n\t"					      \
+		       "lock\n"						      \
+		       "0:\tcmpxchgl %2, %1; setne %0"			      \
+		       : "=a" (ret), "=m" (futex)			      \
+		       : "r" (0), "1" (futex), "0" (1)			      \
+		       : "memory");					      \
+     ret; })
+
+
+# define lll_lock(futex) \
+  (void) ({ int ignore1, ignore2;					      \
+	    __asm __volatile ("cmpl $0, __libc_locking_needed\n\t"	      \
+			      "je,pt 0f\n\t"				      \
+			      "lock\n"					      \
+			      "0:\txaddl %0, %2\n\t"			      \
+			      "jne 1f\n\t"				      \
+			      ".subsection 1\n"				      \
+			      "1:\tleal %2, %%ecx\n\t"			      \
+			      "call __lll_lock_wait\n\t"		      \
+			      "jmp 2f\n\t"				      \
+			      ".previous\n"				      \
+			      "2:"					      \
+			      : "=a" (ignore1), "=&c" (ignore2), "=m" (futex) \
+			      : "0" (-1), "2" (futex)			      \
+			      : "memory"); })
+
+
+# define lll_unlock(futex) \
+  (void) ({ int ignore;							      \
+            __asm __volatile ("cmpl $0, __libc_locking_needed\n\t"	      \
+			      "je,pt 0f\n\t"				      \
+			      "lock\n"					      \
+			      "0:\tincl %0\n\t"				      \
+			      "jng 1f\n\t"				      \
+			      ".subsection 1\n"				      \
+			      "1:\tleal %0, %%eax\n\t"			      \
+			      "call __lll_unlock_wake\n\t"		      \
+			      "jmp 2f\n\t"				      \
+			      ".previous\n"				      \
+			      "2:"					      \
+			      : "=m" (futex), "=&a" (ignore)		      \
+			      : "0" (futex)				      \
+			      : "memory"); })
+#endif
 
 
 #define lll_islocked(futex) \
diff --git a/nptl/sysdeps/unix/sysv/linux/fork-gen.c b/nptl/sysdeps/unix/sysv/linux/libc_pthread_init.c
index ff00261404..d7f1c03b5e 100644
--- a/nptl/sysdeps/unix/sysv/linux/fork-gen.c
+++ b/nptl/sysdeps/unix/sysv/linux/libc_pthread_init.c
@@ -19,19 +19,29 @@
 
 #include <list.h>
 #include "fork.h"
+#include <bits/libc-lock.h>
 
 
 static struct fork_handler pthread_child_handler;
 
+/* Global variable signalled when locking is needed.  */
+int __libc_locking_needed;
+
 
 void
-__register_pthread_fork_handler (ptr, reclaim)
+__libc_pthread_init (ptr, reclaim)
      unsigned long int *ptr;
      void (*reclaim) (void);
 {
+  /* Remember the pointer to the generation counter in libpthread.  */
   __fork_generation_pointer = ptr;
 
+  /* Called by a child after fork.  */
   pthread_child_handler.handler = reclaim;
 
+  /* The fork handler needed by libpthread.  */
   list_add_tail (&pthread_child_handler.list, &__fork_child_list);
+
+  /* Signal the internal locking code that locking is needed now.  */
+  __libc_locking_needed = 1;
 }