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5a8075b116
private futexes are available. * allocatestack.c (allocate_stack): Copy private_futex field from current thread into the new stack. * sysdeps/unix/sysv/linux/x86_64/libc-lowlevellock.S: Use private futexes if they are available. * sysdeps/unix/sysv/linux/i386/i486/libc-lowlevellock.S: Likewise * sysdeps/unix/sysv/linux/x86_64/lowlevellock.S: Adjust so that change in libc-lowlevellock.S allow using private futexes. * sysdeps/unix/sysv/linux/i386/i486/lowlevellock.S: Likewise. * sysdeps/unix/sysv/linux/x86_64/lowlevellock.h: Define FUTEX_PRIVATE_FLAG. * sysdeps/unix/sysv/linux/i386/lowlevellock.h: Likewise. * sysdeps/unix/sysv/linux/x86_64/pthread_once.S: Use private futexes if they are available. * sysdeps/unix/sysv/linux/i386/pthread_once.S: Likewise. * sysdeps/x86_64/tcb-offsets.sym: Add PRIVATE_FUTEX. * sysdeps/i386/tcb-offsets.sym: Likewise. * sysdeps/x86_64/tls.h (tcbhead_t): Add private_futex field. * sysdeps/i386/tls.h (tcbhead_t): Likewise.
600 lines
21 KiB
C
600 lines
21 KiB
C
/* Copyright (C) 2002, 2003, 2004, 2006, 2007 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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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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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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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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#ifndef _LOWLEVELLOCK_H
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#define _LOWLEVELLOCK_H 1
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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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#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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#define SYS_futex 240
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#define FUTEX_WAIT 0
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#define FUTEX_WAKE 1
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#define FUTEX_LOCK_PI 6
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#define FUTEX_UNLOCK_PI 7
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#define FUTEX_TRYLOCK_PI 8
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#define FUTEX_PRIVATE_FLAG 128
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/* Initializer for compatibility lock. */
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#define LLL_MUTEX_LOCK_INITIALIZER (0)
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#define LLL_MUTEX_LOCK_INITIALIZER_LOCKED (1)
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#define LLL_MUTEX_LOCK_INITIALIZER_WAITERS (2)
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#ifdef PIC
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# define LLL_EBX_LOAD "xchgl %2, %%ebx\n"
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# define LLL_EBX_REG "D"
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#else
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# define LLL_EBX_LOAD
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# define LLL_EBX_REG "b"
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#endif
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#ifdef I386_USE_SYSENTER
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# ifdef SHARED
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# define LLL_ENTER_KERNEL "call *%%gs:%P6\n\t"
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# else
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# define LLL_ENTER_KERNEL "call *_dl_sysinfo\n\t"
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# endif
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#else
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# define LLL_ENTER_KERNEL "int $0x80\n\t"
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#endif
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/* Delay in spinlock loop. */
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#define BUSY_WAIT_NOP asm ("rep; nop")
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#define LLL_STUB_UNWIND_INFO_START \
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".section .eh_frame,\"a\",@progbits\n" \
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"5:\t" ".long 7f-6f # Length of Common Information Entry\n" \
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"6:\t" ".long 0x0 # CIE Identifier Tag\n\t" \
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".byte 0x1 # CIE Version\n\t" \
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".ascii \"zR\\0\" # CIE Augmentation\n\t" \
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".uleb128 0x1 # CIE Code Alignment Factor\n\t" \
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".sleb128 -4 # CIE Data Alignment Factor\n\t" \
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".byte 0x8 # CIE RA Column\n\t" \
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".uleb128 0x1 # Augmentation size\n\t" \
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".byte 0x1b # FDE Encoding (pcrel sdata4)\n\t" \
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".byte 0xc # DW_CFA_def_cfa\n\t" \
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".uleb128 0x4\n\t" \
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".uleb128 0x0\n\t" \
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".align 4\n" \
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"7:\t" ".long 17f-8f # FDE Length\n" \
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"8:\t" ".long 8b-5b # FDE CIE offset\n\t" \
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".long 1b-. # FDE initial location\n\t" \
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".long 4b-1b # FDE address range\n\t" \
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".uleb128 0x0 # Augmentation size\n\t" \
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".byte 0x16 # DW_CFA_val_expression\n\t" \
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".uleb128 0x8\n\t" \
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".uleb128 10f-9f\n" \
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"9:\t" ".byte 0x78 # DW_OP_breg8\n\t" \
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".sleb128 3b-1b\n"
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#define LLL_STUB_UNWIND_INFO_END \
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".byte 0x16 # DW_CFA_val_expression\n\t" \
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".uleb128 0x8\n\t" \
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".uleb128 12f-11f\n" \
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"11:\t" ".byte 0x78 # DW_OP_breg8\n\t" \
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".sleb128 3b-2b\n" \
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"12:\t" ".byte 0x40 + (3b-2b-1) # DW_CFA_advance_loc\n\t" \
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".byte 0x16 # DW_CFA_val_expression\n\t" \
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".uleb128 0x8\n\t" \
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".uleb128 16f-13f\n" \
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"13:\t" ".byte 0x78 # DW_OP_breg8\n\t" \
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".sleb128 15f-14f\n\t" \
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".byte 0x0d # DW_OP_const4s\n" \
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"14:\t" ".4byte 3b-.\n\t" \
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".byte 0x1c # DW_OP_minus\n\t" \
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".byte 0x0d # DW_OP_const4s\n" \
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"15:\t" ".4byte 18f-.\n\t" \
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".byte 0x22 # DW_OP_plus\n" \
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"16:\t" ".align 4\n" \
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"17:\t" ".previous\n"
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/* Unwind info for
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1: lea ..., ...
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2: call ...
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3: jmp 18f
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4:
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snippet. */
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#define LLL_STUB_UNWIND_INFO_3 \
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LLL_STUB_UNWIND_INFO_START \
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"10:\t" ".byte 0x40 + (2b-1b) # DW_CFA_advance_loc\n\t" \
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LLL_STUB_UNWIND_INFO_END
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/* Unwind info for
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1: lea ..., ...
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0: movl ..., ...
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2: call ...
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3: jmp 18f
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4:
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snippet. */
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#define LLL_STUB_UNWIND_INFO_4 \
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LLL_STUB_UNWIND_INFO_START \
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"10:\t" ".byte 0x40 + (0b-1b) # DW_CFA_advance_loc\n\t" \
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".byte 0x16 # DW_CFA_val_expression\n\t" \
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".uleb128 0x8\n\t" \
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".uleb128 20f-19f\n" \
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"19:\t" ".byte 0x78 # DW_OP_breg8\n\t" \
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".sleb128 3b-0b\n" \
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"20:\t" ".byte 0x40 + (2b-0b) # DW_CFA_advance_loc\n\t" \
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LLL_STUB_UNWIND_INFO_END
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#define lll_futex_wait(futex, val) \
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({ \
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int __status; \
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register __typeof (val) _val asm ("edx") = (val); \
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__asm __volatile (LLL_EBX_LOAD \
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LLL_ENTER_KERNEL \
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LLL_EBX_LOAD \
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: "=a" (__status) \
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: "0" (SYS_futex), LLL_EBX_REG (futex), "S" (0), \
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"c" (FUTEX_WAIT), "d" (_val), \
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"i" (offsetof (tcbhead_t, sysinfo)) \
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: "memory"); \
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__status; \
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})
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#define lll_futex_timed_wait(futex, val, timeout) \
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({ \
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int __status; \
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register __typeof (val) _val asm ("edx") = (val); \
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__asm __volatile (LLL_EBX_LOAD \
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LLL_ENTER_KERNEL \
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LLL_EBX_LOAD \
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: "=a" (__status) \
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: "0" (SYS_futex), LLL_EBX_REG (futex), "S" (timeout), \
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"c" (FUTEX_WAIT), "d" (_val), \
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"i" (offsetof (tcbhead_t, sysinfo)) \
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: "memory"); \
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__status; \
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})
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#define lll_futex_wake(futex, nr) \
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do { \
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int __ignore; \
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register __typeof (nr) _nr asm ("edx") = (nr); \
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__asm __volatile (LLL_EBX_LOAD \
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LLL_ENTER_KERNEL \
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LLL_EBX_LOAD \
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: "=a" (__ignore) \
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: "0" (SYS_futex), LLL_EBX_REG (futex), \
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"c" (FUTEX_WAKE), "d" (_nr), \
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"i" (0) /* phony, to align next arg's number */, \
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"i" (offsetof (tcbhead_t, sysinfo))); \
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} while (0)
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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 preserve %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_wake (int *__futex)
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__attribute ((regparm (1))) attribute_hidden;
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/* NB: in the lll_mutex_trylock macro we simply return the value in %eax
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after the cmpxchg instruction. In case the operation succeded this
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value is zero. In case the operation failed, the cmpxchg instruction
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has loaded the current value of the memory work which is guaranteed
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to be nonzero. */
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#define lll_mutex_trylock(futex) \
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({ int ret; \
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__asm __volatile (LOCK_INSTR "cmpxchgl %2, %1" \
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: "=a" (ret), "=m" (futex) \
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: "r" (LLL_MUTEX_LOCK_INITIALIZER_LOCKED), "m" (futex),\
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"0" (LLL_MUTEX_LOCK_INITIALIZER) \
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: "memory"); \
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ret; })
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#define lll_robust_mutex_trylock(futex, id) \
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({ int ret; \
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__asm __volatile (LOCK_INSTR "cmpxchgl %2, %1" \
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: "=a" (ret), "=m" (futex) \
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: "r" (id), "m" (futex), \
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"0" (LLL_MUTEX_LOCK_INITIALIZER) \
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: "memory"); \
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ret; })
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#define lll_mutex_cond_trylock(futex) \
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({ int ret; \
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__asm __volatile (LOCK_INSTR "cmpxchgl %2, %1" \
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: "=a" (ret), "=m" (futex) \
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: "r" (LLL_MUTEX_LOCK_INITIALIZER_WAITERS), \
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"m" (futex), "0" (LLL_MUTEX_LOCK_INITIALIZER) \
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: "memory"); \
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ret; })
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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 "cmpxchgl %1, %2\n\t" \
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"jnz _L_mutex_lock_%=\n\t" \
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".subsection 1\n\t" \
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".type _L_mutex_lock_%=,@function\n" \
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"_L_mutex_lock_%=:\n" \
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"1:\tleal %2, %%ecx\n" \
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"2:\tcall __lll_mutex_lock_wait\n" \
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"3:\tjmp 18f\n" \
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"4:\t.size _L_mutex_lock_%=, 4b-1b\n\t" \
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".previous\n" \
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LLL_STUB_UNWIND_INFO_3 \
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"18:" \
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: "=a" (ignore1), "=c" (ignore2), "=m" (futex) \
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: "0" (0), "1" (1), "m" (futex) \
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: "memory"); })
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#define lll_robust_mutex_lock(futex, id) \
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({ int result, ignore; \
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__asm __volatile (LOCK_INSTR "cmpxchgl %1, %2\n\t" \
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"jnz _L_robust_mutex_lock_%=\n\t" \
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".subsection 1\n\t" \
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".type _L_robust_mutex_lock_%=,@function\n" \
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"_L_robust_mutex_lock_%=:\n" \
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"1:\tleal %2, %%ecx\n" \
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"2:\tcall __lll_robust_mutex_lock_wait\n" \
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"3:\tjmp 18f\n" \
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"4:\t.size _L_robust_mutex_lock_%=, 4b-1b\n\t" \
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".previous\n" \
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LLL_STUB_UNWIND_INFO_3 \
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"18:" \
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: "=a" (result), "=c" (ignore), "=m" (futex) \
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: "0" (0), "1" (id), "m" (futex) \
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: "memory"); \
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result; })
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/* Special version of lll_mutex_lock which causes the unlock function to
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always wakeup waiters. */
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#define lll_mutex_cond_lock(futex) \
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(void) ({ int ignore1, ignore2; \
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__asm __volatile (LOCK_INSTR "cmpxchgl %1, %2\n\t" \
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"jnz _L_mutex_cond_lock_%=\n\t" \
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".subsection 1\n\t" \
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".type _L_mutex_cond_lock_%=,@function\n" \
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"_L_mutex_cond_lock_%=:\n" \
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"1:\tleal %2, %%ecx\n" \
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"2:\tcall __lll_mutex_lock_wait\n" \
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"3:\tjmp 18f\n" \
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"4:\t.size _L_mutex_cond_lock_%=, 4b-1b\n\t" \
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".previous\n" \
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LLL_STUB_UNWIND_INFO_3 \
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"18:" \
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: "=a" (ignore1), "=c" (ignore2), "=m" (futex) \
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: "0" (0), "1" (2), "m" (futex) \
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: "memory"); })
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#define lll_robust_mutex_cond_lock(futex, id) \
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({ int result, ignore; \
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__asm __volatile (LOCK_INSTR "cmpxchgl %1, %2\n\t" \
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"jnz _L_robust_mutex_cond_lock_%=\n\t" \
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".subsection 1\n\t" \
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".type _L_robust_mutex_cond_lock_%=,@function\n" \
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"_L_robust_mutex_cond_lock_%=:\n" \
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"1:\tleal %2, %%ecx\n" \
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"2:\tcall __lll_robust_mutex_lock_wait\n" \
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"3:\tjmp 18f\n" \
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"4:\t.size _L_robust_mutex_cond_lock_%=, 4b-1b\n\t" \
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".previous\n" \
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LLL_STUB_UNWIND_INFO_3 \
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"18:" \
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: "=a" (result), "=c" (ignore), "=m" (futex) \
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: "0" (0), "1" (id | FUTEX_WAITERS), "m" (futex) \
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: "memory"); \
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result; })
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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 "cmpxchgl %1, %3\n\t" \
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"jnz _L_mutex_timedlock_%=\n\t" \
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".subsection 1\n\t" \
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".type _L_mutex_timedlock_%=,@function\n" \
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"_L_mutex_timedlock_%=:\n" \
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"1:\tleal %3, %%ecx\n" \
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"0:\tmovl %7, %%edx\n" \
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"2:\tcall __lll_mutex_timedlock_wait\n" \
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"3:\tjmp 18f\n" \
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"4:\t.size _L_mutex_timedlock_%=, 4b-1b\n\t" \
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".previous\n" \
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LLL_STUB_UNWIND_INFO_4 \
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"18:" \
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: "=a" (result), "=c" (ignore1), "=&d" (ignore2), \
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"=m" (futex) \
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: "0" (0), "1" (1), "m" (futex), "m" (timeout) \
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: "memory"); \
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result; })
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#define lll_robust_mutex_timedlock(futex, timeout, id) \
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({ int result, ignore1, ignore2; \
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__asm __volatile (LOCK_INSTR "cmpxchgl %1, %3\n\t" \
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"jnz _L_robust_mutex_timedlock_%=\n\t" \
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".subsection 1\n\t" \
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".type _L_robust_mutex_timedlock_%=,@function\n" \
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"_L_robust_mutex_timedlock_%=:\n" \
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"1:\tleal %3, %%ecx\n" \
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"0:\tmovl %7, %%edx\n" \
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"2:\tcall __lll_robust_mutex_timedlock_wait\n" \
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"3:\tjmp 18f\n" \
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"4:\t.size _L_robust_mutex_timedlock_%=, 4b-1b\n\t" \
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".previous\n" \
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LLL_STUB_UNWIND_INFO_4 \
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"18:" \
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: "=a" (result), "=c" (ignore1), "=&d" (ignore2), \
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"=m" (futex) \
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: "0" (0), "1" (id), "m" (futex), "m" (timeout) \
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: "memory"); \
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result; })
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#define lll_mutex_unlock(futex) \
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(void) ({ int ignore; \
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__asm __volatile (LOCK_INSTR "subl $1, %0\n\t" \
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"jne _L_mutex_unlock_%=\n\t" \
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".subsection 1\n\t" \
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".type _L_mutex_unlock_%=,@function\n" \
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"_L_mutex_unlock_%=:\n" \
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"1:\tleal %0, %%eax\n" \
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"2:\tcall __lll_mutex_unlock_wake\n" \
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"3:\tjmp 18f\n" \
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"4:\t.size _L_mutex_unlock_%=, 4b-1b\n\t" \
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".previous\n" \
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LLL_STUB_UNWIND_INFO_3 \
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"18:" \
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: "=m" (futex), "=&a" (ignore) \
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: "m" (futex) \
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: "memory"); })
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#define lll_robust_mutex_unlock(futex) \
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(void) ({ int ignore; \
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__asm __volatile (LOCK_INSTR "andl %2, %0\n\t" \
|
|
"jne _L_robust_mutex_unlock_%=\n\t" \
|
|
".subsection 1\n\t" \
|
|
".type _L_robust_mutex_unlock_%=,@function\n" \
|
|
"_L_robust_mutex_unlock_%=:\n\t" \
|
|
"1:\tleal %0, %%eax\n" \
|
|
"2:\tcall __lll_mutex_unlock_wake\n" \
|
|
"3:\tjmp 18f\n" \
|
|
"4:\t.size _L_robust_mutex_unlock_%=, 4b-1b\n\t"\
|
|
".previous\n" \
|
|
LLL_STUB_UNWIND_INFO_3 \
|
|
"18:" \
|
|
: "=m" (futex), "=&a" (ignore) \
|
|
: "i" (FUTEX_WAITERS), "m" (futex) \
|
|
: "memory"); })
|
|
|
|
|
|
#define lll_robust_mutex_dead(futex) \
|
|
(void) ({ int __ignore; \
|
|
register int _nr asm ("edx") = 1; \
|
|
__asm __volatile (LOCK_INSTR "orl %5, (%2)\n\t" \
|
|
LLL_EBX_LOAD \
|
|
LLL_ENTER_KERNEL \
|
|
LLL_EBX_LOAD \
|
|
: "=a" (__ignore) \
|
|
: "0" (SYS_futex), LLL_EBX_REG (&(futex)), \
|
|
"c" (FUTEX_WAKE), "d" (_nr), \
|
|
"i" (FUTEX_OWNER_DIED), \
|
|
"i" (offsetof (tcbhead_t, sysinfo))); })
|
|
|
|
|
|
#define lll_futex_wake(futex, nr) \
|
|
do { \
|
|
int __ignore; \
|
|
register __typeof (nr) _nr asm ("edx") = (nr); \
|
|
__asm __volatile (LLL_EBX_LOAD \
|
|
LLL_ENTER_KERNEL \
|
|
LLL_EBX_LOAD \
|
|
: "=a" (__ignore) \
|
|
: "0" (SYS_futex), LLL_EBX_REG (futex), \
|
|
"c" (FUTEX_WAKE), "d" (_nr), \
|
|
"i" (0) /* phony, to align next arg's number */, \
|
|
"i" (offsetof (tcbhead_t, sysinfo))); \
|
|
} while (0)
|
|
|
|
|
|
#define lll_mutex_islocked(futex) \
|
|
(futex != 0)
|
|
|
|
|
|
/* We have a separate internal lock implementation which is not tied
|
|
to binary compatibility. */
|
|
|
|
/* Type for lock object. */
|
|
typedef int lll_lock_t;
|
|
|
|
/* Initializers for lock. */
|
|
#define LLL_LOCK_INITIALIZER (0)
|
|
#define LLL_LOCK_INITIALIZER_LOCKED (1)
|
|
|
|
|
|
extern int __lll_lock_wait (int val, int *__futex)
|
|
__attribute ((regparm (2))) attribute_hidden;
|
|
extern int __lll_unlock_wake (int *__futex)
|
|
__attribute ((regparm (1))) attribute_hidden;
|
|
extern int lll_unlock_wake_cb (int *__futex) attribute_hidden;
|
|
|
|
|
|
/* The states of a lock are:
|
|
0 - untaken
|
|
1 - taken by one user
|
|
2 - taken by more users */
|
|
|
|
|
|
#if defined NOT_IN_libc || defined UP
|
|
# define lll_trylock(futex) lll_mutex_trylock (futex)
|
|
# define lll_lock(futex) lll_mutex_lock (futex)
|
|
# define lll_unlock(futex) lll_mutex_unlock (futex)
|
|
#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. */
|
|
# include <tls.h>
|
|
|
|
# define lll_trylock(futex) \
|
|
({ unsigned char ret; \
|
|
__asm __volatile ("cmpl $0, %%gs:%P5\n\t" \
|
|
"je 0f\n\t" \
|
|
"lock\n" \
|
|
"0:\tcmpxchgl %2, %1; setne %0" \
|
|
: "=a" (ret), "=m" (futex) \
|
|
: "r" (LLL_MUTEX_LOCK_INITIALIZER_LOCKED), "m" (futex),\
|
|
"0" (LLL_MUTEX_LOCK_INITIALIZER), \
|
|
"i" (offsetof (tcbhead_t, multiple_threads)) \
|
|
: "memory"); \
|
|
ret; })
|
|
|
|
|
|
# define lll_lock(futex) \
|
|
(void) ({ int ignore1, ignore2; \
|
|
__asm __volatile ("cmpl $0, %%gs:%P6\n\t" \
|
|
"je 0f\n\t" \
|
|
"lock\n" \
|
|
"0:\tcmpxchgl %1, %2\n\t" \
|
|
"jnz _L_lock_%=\n\t" \
|
|
".subsection 1\n\t" \
|
|
".type _L_lock_%=,@function\n" \
|
|
"_L_lock_%=:\n" \
|
|
"1:\tleal %2, %%ecx\n" \
|
|
"2:\tcall __lll_mutex_lock_wait\n" \
|
|
"3:\tjmp 18f\n" \
|
|
"4:\t.size _L_lock_%=, 4b-1b\n\t" \
|
|
".previous\n" \
|
|
LLL_STUB_UNWIND_INFO_3 \
|
|
"18:" \
|
|
: "=a" (ignore1), "=c" (ignore2), "=m" (futex) \
|
|
: "0" (0), "1" (1), "m" (futex), \
|
|
"i" (offsetof (tcbhead_t, multiple_threads)) \
|
|
: "memory"); })
|
|
|
|
|
|
# define lll_unlock(futex) \
|
|
(void) ({ int ignore; \
|
|
__asm __volatile ("cmpl $0, %%gs:%P3\n\t" \
|
|
"je 0f\n\t" \
|
|
"lock\n" \
|
|
"0:\tsubl $1,%0\n\t" \
|
|
"jne _L_unlock_%=\n\t" \
|
|
".subsection 1\n\t" \
|
|
".type _L_unlock_%=,@function\n" \
|
|
"_L_unlock_%=:\n" \
|
|
"1:\tleal %0, %%eax\n" \
|
|
"2:\tcall __lll_mutex_unlock_wake\n" \
|
|
"3:\tjmp 18f\n\t" \
|
|
"4:\t.size _L_unlock_%=, 4b-1b\n\t" \
|
|
".previous\n" \
|
|
LLL_STUB_UNWIND_INFO_3 \
|
|
"18:" \
|
|
: "=m" (futex), "=&a" (ignore) \
|
|
: "m" (futex), \
|
|
"i" (offsetof (tcbhead_t, multiple_threads)) \
|
|
: "memory"); })
|
|
#endif
|
|
|
|
|
|
#define lll_islocked(futex) \
|
|
(futex != LLL_LOCK_INITIALIZER)
|
|
|
|
|
|
/* The kernel notifies a process with uses CLONE_CLEARTID via futex
|
|
wakeup when the clone terminates. The memory location contains the
|
|
thread ID while the clone is running and is reset to zero
|
|
afterwards.
|
|
|
|
The macro parameter must not have any side effect. */
|
|
#define lll_wait_tid(tid) \
|
|
do { \
|
|
int __ignore; \
|
|
register __typeof (tid) _tid asm ("edx") = (tid); \
|
|
if (_tid != 0) \
|
|
__asm __volatile (LLL_EBX_LOAD \
|
|
"1:\tmovl %1, %%eax\n\t" \
|
|
LLL_ENTER_KERNEL \
|
|
"cmpl $0, (%%ebx)\n\t" \
|
|
"jne 1b\n\t" \
|
|
LLL_EBX_LOAD \
|
|
: "=&a" (__ignore) \
|
|
: "i" (SYS_futex), LLL_EBX_REG (&tid), "S" (0), \
|
|
"c" (FUTEX_WAIT), "d" (_tid), \
|
|
"i" (offsetof (tcbhead_t, sysinfo)) \
|
|
: "memory"); \
|
|
} while (0)
|
|
|
|
extern int __lll_timedwait_tid (int *tid, const struct timespec *abstime)
|
|
__attribute__ ((regparm (2))) attribute_hidden;
|
|
#define lll_timedwait_tid(tid, abstime) \
|
|
({ \
|
|
int __result = 0; \
|
|
if (tid != 0) \
|
|
{ \
|
|
if (abstime->tv_nsec < 0 || abstime->tv_nsec >= 1000000000) \
|
|
__result = EINVAL; \
|
|
else \
|
|
__result = __lll_timedwait_tid (&tid, abstime); \
|
|
} \
|
|
__result; })
|
|
|
|
|
|
/* Conditional variable handling. */
|
|
|
|
extern void __lll_cond_wait (pthread_cond_t *cond)
|
|
__attribute ((regparm (1))) attribute_hidden;
|
|
extern int __lll_cond_timedwait (pthread_cond_t *cond,
|
|
const struct timespec *abstime)
|
|
__attribute ((regparm (2))) attribute_hidden;
|
|
extern void __lll_cond_wake (pthread_cond_t *cond)
|
|
__attribute ((regparm (1))) attribute_hidden;
|
|
extern void __lll_cond_broadcast (pthread_cond_t *cond)
|
|
__attribute ((regparm (1))) attribute_hidden;
|
|
|
|
|
|
#define lll_cond_wait(cond) \
|
|
__lll_cond_wait (cond)
|
|
#define lll_cond_timedwait(cond, abstime) \
|
|
__lll_cond_timedwait (cond, abstime)
|
|
#define lll_cond_wake(cond) \
|
|
__lll_cond_wake (cond)
|
|
#define lll_cond_broadcast(cond) \
|
|
__lll_cond_broadcast (cond)
|
|
|
|
|
|
#endif /* lowlevellock.h */
|