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			72 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			72 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* low level locking for pthread library.  Generic futex-using version.
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|    Copyright (C) 2003-2025 Free Software Foundation, Inc.
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|    This file is part of the GNU C Library.
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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, see
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|    <https://www.gnu.org/licenses/>.  */
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| 
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| #include <sysdep.h>
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| #include <futex-internal.h>
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| #include <atomic.h>
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| #include <stap-probe.h>
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| 
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| void
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| __lll_lock_wait_private (int *futex)
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| {
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|   if (atomic_load_relaxed (futex) == 2)
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|     goto futex;
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| 
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|   while (atomic_exchange_acquire (futex, 2) != 0)
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|     {
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|     futex:
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|       LIBC_PROBE (lll_lock_wait_private, 1, futex);
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|       futex_wait ((unsigned int *) futex, 2, LLL_PRIVATE); /* Wait if *futex == 2.  */
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|     }
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| }
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| libc_hidden_def (__lll_lock_wait_private)
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| 
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| void
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| __lll_lock_wait (int *futex, int private)
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| {
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|   if (atomic_load_relaxed (futex) == 2)
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|     goto futex;
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| 
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|   while (atomic_exchange_acquire (futex, 2) != 0)
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|     {
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|     futex:
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|       LIBC_PROBE (lll_lock_wait, 1, futex);
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|       futex_wait ((unsigned int *) futex, 2, private); /* Wait if *futex == 2.  */
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|     }
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| }
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| libc_hidden_def (__lll_lock_wait)
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| 
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| void
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| __lll_lock_wake_private (int *futex)
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| {
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|   lll_futex_wake (futex, 1, LLL_PRIVATE);
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| }
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| libc_hidden_def (__lll_lock_wake_private)
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| 
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| void
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| __lll_lock_wake (int *futex, int private)
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| {
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|   lll_futex_wake (futex, 1, private);
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| }
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| libc_hidden_def (__lll_lock_wake)
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| 
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| #if ENABLE_ELISION_SUPPORT
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| int __pthread_force_elision;
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| libc_hidden_data_def (__pthread_force_elision)
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| #endif
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