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	2002-12-13 Ulrich Drepper <drepper@redhat.com> * misc/syslog.c (log_cleanup): Don't use parameter in __libc_lock_unlock call, use syslog_lock directly. Adjust callers to pass NULL instead of a pointer to syslog_lock.
		
			
				
	
	
		
			328 lines
		
	
	
		
			10 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			328 lines
		
	
	
		
			10 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* Copyright (C) 2002 Free Software Foundation, Inc.
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|    This file is part of the GNU C Library.
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|    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
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| 
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|    The GNU C Library is free software; you can redistribute it and/or
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|    modify it under the terms of the GNU Lesser General Public
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|    License as published by the Free Software Foundation; either
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|    version 2.1 of the License, or (at your option) any later version.
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| 
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|    The GNU C Library is distributed in the hope that it will be useful,
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|    but WITHOUT ANY WARRANTY; without even the implied warranty of
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|    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|    Lesser General Public License for more details.
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| 
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|    You should have received a copy of the GNU Lesser General Public
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|    License along with the GNU C Library; if not, write to the Free
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|    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
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|    02111-1307 USA.  */
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| 
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| #ifndef _LOWLEVELLOCK_H
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| #define _LOWLEVELLOCK_H	1
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| 
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| #include <time.h>
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| #include <sys/param.h>
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| #include <bits/pthreadtypes.h>
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| 
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| #ifndef LOCK_INSTR
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| # ifdef UP
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| #  define LOCK_INSTR	/* nothing */
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| # else
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| #  define LOCK_INSTR "lock;"
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| # endif
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| #endif
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| 
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| #define SYS_futex		240
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| #define FUTEX_WAIT		0
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| #define FUTEX_WAKE		1
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| 
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| 
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| /* Initializer for compatibility lock.  */
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| #define LLL_MUTEX_LOCK_INITIALIZER (0)
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| 
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| 
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| /* Does not preserve %eax and %ecx.  */
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| extern int __lll_mutex_lock_wait (int val, int *__futex)
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|      __attribute ((regparm (2))) attribute_hidden;
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| /* Does not preserver %eax, %ecx, and %edx.  */
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| extern int __lll_mutex_timedlock_wait (int val, int *__futex,
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| 				 const struct timespec *abstime)
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|      __attribute ((regparm (3))) attribute_hidden;
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| /* Preserves all registers but %eax.  */
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| extern int __lll_mutex_unlock_wait (int *__futex)
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|      __attribute ((regparm (1))) attribute_hidden;
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| 
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| 
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| #define lll_mutex_trylock(futex) \
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|   ({ unsigned char ret;							      \
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|      __asm __volatile (LOCK_INSTR "cmpxchgl %2, %1; setne %0"		      \
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| 		       : "=a" (ret), "=m" (futex)			      \
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| 		       : "r" (1), "1" (futex), "0" (0)			      \
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| 		       : "memory");					      \
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|      ret; })
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| 
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| 
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| #define lll_mutex_lock(futex) \
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|   (void) ({ int ignore1, ignore2;					      \
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| 	    __asm __volatile (LOCK_INSTR "xaddl %0, %2\n\t"		      \
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| 			      "testl %0, %0\n\t"			      \
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| 			      "jne 1f\n\t"				      \
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| 			      ".subsection 1\n"				      \
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| 			      "1:\tleal %2, %%ecx\n\t"			      \
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| 			      "call __lll_mutex_lock_wait\n\t"		      \
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| 			      "jmp 2f\n\t"				      \
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| 			      ".previous\n"				      \
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| 			      "2:"					      \
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| 			      : "=a" (ignore1), "=&c" (ignore2), "=m" (futex) \
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| 			      : "0" (1), "2" (futex)			      \
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| 			      : "memory"); })
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| 
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| 
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| #define lll_mutex_timedlock(futex, timeout) \
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|   ({ int result, ignore1, ignore2;					      \
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|      __asm __volatile (LOCK_INSTR "xaddl %0, %3\n\t"			      \
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| 		       "testl %0, %0\n\t"				      \
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| 		       "jne 1f\n\t"					      \
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| 		       ".subsection 1\n"				      \
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| 		       "1:\tleal %3, %%ecx\n\t"				      \
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| 		       "movl %6, %%edx\n\t"				      \
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| 		       "call __lll_mutex_timedlock_wait\n\t"		      \
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| 		       "jmp 2f\n\t"					      \
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| 		       ".previous\n"					      \
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| 		       "2:"						      \
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| 		       : "=a" (result), "=&c" (ignore1), "=&d" (ignore2),     \
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| 			 "=m" (futex)					      \
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| 		       : "0" (1), "3" (futex), "m" (timeout)		      \
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| 		       : "memory");					      \
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|      result; })
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| 
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| 
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| #define lll_mutex_unlock(futex) \
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|   (void) ({ int ignore;							      \
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|             __asm __volatile (LOCK_INSTR "decl %0\n\t"			      \
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| 			      "jne 1f\n\t"				      \
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| 			      ".subsection 1\n"				      \
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| 			      "1:\tleal %0, %%eax\n\t"			      \
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| 			      "call __lll_mutex_unlock_wake\n\t"	      \
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| 			      "jmp 2f\n\t"				      \
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| 			      ".previous\n"				      \
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| 			      "2:"					      \
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| 			      : "=m" (futex), "=&a" (ignore)		      \
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| 			      : "0" (futex)				      \
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| 			      : "memory"); })
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| 
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| 
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| #define lll_mutex_islocked(futex) \
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|   (futex != 0)
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| 
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| 
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| /* We have a separate internal lock implementation which is not tied
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|    to binary compatibility.  */
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| 
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| /* Type for lock object.  */
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| typedef int lll_lock_t;
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| 
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| /* Initializers for lock.  */
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| #define LLL_LOCK_INITIALIZER		(1)
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| #define LLL_LOCK_INITIALIZER_LOCKED	(0)
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| 
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| 
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| extern int __lll_lock_wait (int val, int *__futex)
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|      __attribute ((regparm (2))) attribute_hidden;
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| extern int __lll_unlock_wake (int *__futex)
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|      __attribute ((regparm (1))) attribute_hidden;
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| extern int lll_unlock_wake_cb (int *__futex) attribute_hidden;
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| 
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| 
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| /* The states of a lock are:
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|     1  -  untaken
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|     0  -  taken by one user
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|    <0  -  taken by more users */
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| 
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| 
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| #if defined NOT_IN_libc || defined UP
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| # define lll_trylock(futex) \
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|   ({ unsigned char ret;							      \
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|      __asm __volatile (LOCK_INSTR "cmpxchgl %2, %1; setne %0"		      \
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| 		       : "=a" (ret), "=m" (futex)			      \
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| 		       : "r" (0), "1" (futex), "0" (1)			      \
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| 		       : "memory");					      \
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|      ret; })
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| 
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| 
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| # define lll_lock(futex) \
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|   (void) ({ int ignore1, ignore2;					      \
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| 	    __asm __volatile (LOCK_INSTR "xaddl %0, %2\n\t"		      \
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| 			      "jne 1f\n\t"				      \
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| 			      ".subsection 1\n"				      \
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| 			      "1:\tleal %2, %%ecx\n\t"			      \
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| 			      "call __lll_lock_wait\n\t"		      \
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| 			      "jmp 2f\n\t"				      \
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| 			      ".previous\n"				      \
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| 			      "2:"					      \
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| 			      : "=a" (ignore1), "=&c" (ignore2), "=m" (futex) \
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| 			      : "0" (-1), "2" (futex)			      \
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| 			      : "memory"); })
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| 
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| 
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| # define lll_unlock(futex) \
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|   (void) ({ int ignore;							      \
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|             __asm __volatile (LOCK_INSTR "incl %0\n\t"			      \
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| 			      "jng 1f\n\t"				      \
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| 			      ".subsection 1\n"				      \
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| 			      "1:\tleal %0, %%eax\n\t"			      \
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| 			      "call __lll_unlock_wake\n\t"		      \
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| 			      "jmp 2f\n\t"				      \
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| 			      ".previous\n"				      \
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| 			      "2:"					      \
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| 			      : "=m" (futex), "=&a" (ignore)		      \
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| 			      : "0" (futex)				      \
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| 			      : "memory"); })
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| #else
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| /* Special versions of the macros for use in libc itself.  They avoid
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|    the lock prefix when the thread library is not used.
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| 
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|    XXX In future we might even want to avoid it on UP machines.  */
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| # include <tls.h>
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| 
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| /* Nonzero if locking is needed.  */
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| extern int __libc_locking_needed attribute_hidden;
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| 
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| # define lll_trylock(futex) \
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|   ({ unsigned char ret;							      \
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|      __asm __volatile ("cmpl $0, %%gs:%P5\n\t"				      \
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| 		       "je,pt 0f\n\t"					      \
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| 		       "lock\n"						      \
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| 		       "0:\tcmpxchgl %2, %1; setne %0"			      \
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| 		       : "=a" (ret), "=m" (futex)			      \
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| 		       : "r" (0), "1" (futex), "0" (1),			      \
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| 		         "i" (offsetof (tcbhead_t, multiple_threads))	      \
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| 		       : "memory");					      \
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|      ret; })
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| 
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| 
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| # define lll_lock(futex) \
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|   (void) ({ int ignore1, ignore2;					      \
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| 	    __asm __volatile ("cmpl $0, %%gs:%P5\n\t"			      \
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| 			      "je,pt 0f\n\t"				      \
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| 			      "lock\n"					      \
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| 			      "0:\txaddl %0, %2\n\t"			      \
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| 			      "jne 1f\n\t"				      \
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| 			      ".subsection 1\n"				      \
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| 			      "1:\tleal %2, %%ecx\n\t"			      \
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| 			      "call __lll_lock_wait\n\t"		      \
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| 			      "jmp 2f\n\t"				      \
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| 			      ".previous\n"				      \
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| 			      "2:"					      \
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| 			      : "=a" (ignore1), "=&c" (ignore2), "=m" (futex) \
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| 			      : "0" (-1), "2" (futex),			      \
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| 		                "i" (offsetof (tcbhead_t, multiple_threads))  \
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| 			      : "memory"); })
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| 
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| 
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| # define lll_unlock(futex) \
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|   (void) ({ int ignore;							      \
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|             __asm __volatile ("cmpl $0, %%gs:%P3\n\t"			      \
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| 			      "je,pt 0f\n\t"				      \
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| 			      "lock\n"					      \
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| 			      "0:\tincl %0\n\t"				      \
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| 			      "jng 1f\n\t"				      \
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| 			      ".subsection 1\n"				      \
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| 			      "1:\tleal %0, %%eax\n\t"			      \
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| 			      "call __lll_unlock_wake\n\t"		      \
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| 			      "jmp 2f\n\t"				      \
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| 			      ".previous\n"				      \
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| 			      "2:"					      \
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| 			      : "=m" (futex), "=&a" (ignore)		      \
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| 			      : "0" (futex),				      \
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| 				"i" (offsetof (tcbhead_t, multiple_threads))  \
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| 			      : "memory"); })
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| #endif
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| 
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| 
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| #define lll_islocked(futex) \
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|   (futex != 0)
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| 
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| 
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| /* The kernel notifies a process with uses CLONE_CLEARTID via futex
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|    wakeup when the clone terminates.  The memory location contains the
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|    thread ID while the clone is running and is reset to zero
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|    afterwards.
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| 
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|    The macro parameter must not have any side effect.  */
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| #ifdef PIC
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| # define LLL_TID_EBX_LOAD	"xchgl %2, %%ebx\n"
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| # define LLL_TID_EBX_REG	"D"
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| #else
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| # define LLL_TID_EBX_LOAD
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| # define LLL_TID_EBX_REG	"b"
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| #endif
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| #define lll_wait_tid(tid) \
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|   do {									      \
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|     int __ignore;							      \
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|     register __typeof (tid) _tid asm ("edx") = (tid);			      \
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|     if (_tid != 0)							      \
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|       __asm __volatile (LLL_TID_EBX_LOAD				      \
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| 			"1:\tmovl %1, %%eax\n\t"			      \
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| 			"int $0x80\n\t"					      \
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| 			"cmpl $0, (%%ebx)\n\t"				      \
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| 			"jne,pn 1b\n\t"					      \
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| 			LLL_TID_EBX_LOAD				      \
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| 			: "=&a" (__ignore)				      \
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| 			: "i" (SYS_futex), LLL_TID_EBX_REG (&tid), "S" (0),   \
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| 			  "c" (FUTEX_WAIT), "d" (_tid));		      \
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|   } while (0)
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| 
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| extern int __lll_timedwait_tid (int *tid, const struct timespec *abstime)
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|      __attribute__ ((regparm (2))) attribute_hidden;
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| #define lll_timedwait_tid(tid, abstime) \
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|   ({									      \
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|     int __result = 0;							      \
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|     if (tid != 0)							      \
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|       {									      \
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| 	if (abstime == NULL || abstime->tv_nsec >= 1000000000)		      \
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| 	  __result = EINVAL;						      \
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| 	else								      \
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| 	  __result = __lll_timedwait_tid (&tid, abstime);		      \
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|       }									      \
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|     __result; })
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| 
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| 
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| #define lll_wake_tid(tid) \
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|   do {									      \
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|     int __ignore;							      \
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|     (tid) = 0;								      \
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|     __asm __volatile (LLL_TID_EBX_LOAD					      \
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| 		      "\tint $0x80\n\t"					      \
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| 		      LLL_TID_EBX_LOAD					      \
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| 		      : "=a" (__ignore)					      \
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| 		      : "0" (SYS_futex), LLL_TID_EBX_REG (&(tid)), "S" (0),   \
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| 			"c" (FUTEX_WAKE), "d" (0x7fffffff));		      \
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|   } while (0)
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| 
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| 
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| /* Conditional variable handling.  */
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| 
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| extern void __lll_cond_wait (pthread_cond_t *cond)
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|      __attribute ((regparm (1))) attribute_hidden;
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| extern int __lll_cond_timedwait (pthread_cond_t *cond,
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| 				 const struct timespec *abstime)
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|      __attribute ((regparm (2))) attribute_hidden;
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| extern void __lll_cond_wake (pthread_cond_t *cond)
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|      __attribute ((regparm (1))) attribute_hidden;
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| extern void __lll_cond_broadcast (pthread_cond_t *cond)
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|      __attribute ((regparm (1))) attribute_hidden;
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| 
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| 
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| #define lll_cond_wait(cond) \
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|   __lll_cond_wait (cond)
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| #define lll_cond_timedwait(cond, abstime) \
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|   __lll_cond_timedwait (cond, abstime)
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| #define lll_cond_wake(cond) \
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|   __lll_cond_wake (cond)
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| #define lll_cond_broadcast(cond) \
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|   __lll_cond_broadcast (cond)
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| 
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| 
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| #endif	/* lowlevellock.h */
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