projects / apple / libc.git / blame
| Commit | Line | Data |
|---|---|---|
| 8e029c65 A |
1 | /* |
| 2 | * Copyright (c) 2006 Apple Computer, Inc. All rights reserved. | |
| 3 | * | |
| 4 | * @APPLE_LICENSE_HEADER_START@ | |
| 5 | * | |
| 6 | * This file contains Original Code and/or Modifications of Original Code | |
| 7 | * as defined in and that are subject to the Apple Public Source License | |
| 8 | * Version 2.0 (the 'License'). You may not use this file except in | |
| 9 | * compliance with the License. Please obtain a copy of the License at | |
| 10 | * http://www.opensource.apple.com/apsl/ and read it before using this | |
| 11 | * file. | |
| 12 | * | |
| 13 | * The Original Code and all software distributed under the License are | |
| 14 | * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER | |
| 15 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, | |
| 16 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, | |
| 17 | * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. | |
| 18 | * Please see the License for the specific language governing rights and | |
| 19 | * limitations under the License. | |
| 20 | * | |
| 21 | * @APPLE_LICENSE_HEADER_END@ | |
| 22 | */ | |
| 8e029c65 | 23 | |
| 224c7076 | 24 | #include <machine/cpu_capabilities.h> |
| ad3c9f2a | 25 | #include <architecture/i386/asm_help.h> |
| 224c7076 A |
26 | |
| 27 | .text | |
| 28 | .align 2 | |
| 34e8f829 A |
29 | .globl __commpage_pthread_mutex_lock |
| 30 | __commpage_pthread_mutex_lock: | |
| 1f2f436a A |
31 | pushl %ebp // set up frame for backtrace |
| 32 | movl %esp,%ebp | |
| 33 | pushl %esi | |
| 34 | pushl %edi | |
| 35 | pushl %ebx | |
| 36 | xorl %ebx,%ebx // clear "preemption pending" flag | |
| 37 | movl 20(%esp),%edi // %edi == ptr to LVAL/UVAL structure | |
| 38 | lea 20(%esp),%esi // %esi == ptr to argument list | |
| 39 | movl _COMM_PAGE_SPIN_COUNT, %edx | |
| 40 | movl 16(%esi),%ecx // get mask (ie, PTHRW_EBIT etc) | |
| 41 | 1: | |
| 42 | testl 0(%edi),%ecx // is mutex available? | |
| 43 | jz 2f // yes, it is available | |
| 44 | pause | |
| 45 | decl %edx // decrement max spin count | |
| 46 | jnz 1b // keep spinning | |
| 47 | 2: | |
| ad3c9f2a A |
48 | EXTERN_TO_REG(_commpage_pfz_base, %ecx) |
| 49 | movl (%ecx), %ecx | |
| 50 | addl $(_COMM_TEXT_PFZ_MUTEX_LOCK_OFFSET), %ecx | |
| 1f2f436a A |
51 | call *%ecx |
| 52 | testl %ebx,%ebx // pending preemption? | |
| 53 | jz 3f | |
| 54 | pushl %eax // save return value across sysenter | |
| 55 | call _preempt | |
| 56 | popl %eax | |
| 57 | 3: | |
| 58 | popl %ebx | |
| 59 | popl %edi | |
| 60 | popl %esi | |
| 61 | popl %ebp | |
| 62 | ret |