/* * Copyright (c) 2003-2009 Apple, Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. The rights granted to you under the License * may not be used to create, or enable the creation or redistribution of, * unlawful or unlicensed copies of an Apple operating system, or to * circumvent, violate, or enable the circumvention or violation of, any * terms of an Apple operating system software license agreement. * * Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ #include <sys/appleapiopts.h> #include <machine/cpu_capabilities.h> #include <platfunc.h> #include <mach/i386/syscall_sw.h> PLATFUNC_FUNCTION_START(OSSpinLockTry, up, 32, 4) PLATFUNC_FUNCTION_START(_spin_lock_try, up, 32, 4) movl 4(%esp), %ecx xorl %eax, %eax orl $-1, %edx cmpxchgl %edx, (%ecx) setz %dl movzbl %dl, %eax ret PLATFUNC_DESCRIPTOR(OSSpinLockTry,up,kUP,0) PLATFUNC_DESCRIPTOR(_spin_lock_try,up,kUP,0) PLATFUNC_FUNCTION_START_GENERIC(OSSpinLockTry, mp, 32, 4) PLATFUNC_FUNCTION_START_GENERIC(_spin_lock_try, mp, 32, 4) movl 4(%esp), %ecx xorl %eax, %eax orl $-1, %edx lock cmpxchgl %edx, (%ecx) setz %dl movzbl %dl, %eax ret PLATFUNC_DESCRIPTOR(OSSpinLockTry,mp,0,kUP) PLATFUNC_DESCRIPTOR(_spin_lock_try,mp,0,kUP) PLATFUNC_FUNCTION_START(spin_lock, up, 32, 4) PLATFUNC_FUNCTION_START(OSSpinLockLock, up, 32, 4) PLATFUNC_FUNCTION_START(_spin_lock, up, 32, 4) Lspin_lock_up: movl 4(%esp), %ecx xorl %eax, %eax orl $-1, %edx cmpxchgl %edx, (%ecx) jnz 1f ret 1: /* failed to get lock so relinquish the processor immediately on UP */ pushl $1 /* 1 ms */ pushl $1 /* SWITCH_OPTION_DEPRESS */ pushl $0 /* THREAD_NULL */ pushl $0 /* push dummy stack ret addr */ movl $-61,%eax /* SYSCALL_THREAD_SWITCH */ int $(MACH_INT) addl $16, %esp /* adjust stack*/ jmp Lspin_lock_up PLATFUNC_DESCRIPTOR(spin_lock,up,kUP,0) PLATFUNC_DESCRIPTOR(OSSpinLockLock,up,kUP,0) PLATFUNC_DESCRIPTOR(_spin_lock,up,kUP,0) PLATFUNC_FUNCTION_START_GENERIC(spin_lock, mp, 32, 4) PLATFUNC_FUNCTION_START_GENERIC(OSSpinLockLock, mp, 32, 4) PLATFUNC_FUNCTION_START_GENERIC(_spin_lock, mp, 32, 4) Lspin_lock_mp: movl 4(%esp), %ecx xorl %eax, %eax 0: orl $-1, %edx lock cmpxchgl %edx, (%ecx) jnz 1f ret 1: xorl %eax, %eax movl $(MP_SPIN_TRIES), %edx 2: pause cmpl %eax, (%ecx) jz 0b /* favor success and slow down spin loop */ decl %edx jnz 2b /* failed to get lock after spinning so relinquish */ pushl $1 /* 1 ms */ pushl $1 /* SWITCH_OPTION_DEPRESS */ pushl $0 /* THREAD_NULL */ pushl $0 /* push dummy stack ret addr */ movl $-61,%eax /* SYSCALL_THREAD_SWITCH */ int $(MACH_INT) addl $16, %esp /* adjust stack*/ jmp Lspin_lock_mp PLATFUNC_DESCRIPTOR(spin_lock,mp,0,kUP) PLATFUNC_DESCRIPTOR(OSSpinLockLock,mp,0,kUP) PLATFUNC_DESCRIPTOR(_spin_lock,mp,0,kUP) .align 2, 0x90 .globl _OSSpinLockUnlock .globl _spin_unlock .globl __spin_unlock _OSSpinLockUnlock: _spin_unlock: __spin_unlock: movl 4(%esp), %eax movl $0, (%eax) ret