projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 79e1dd05 AV |
1 | /* |
| 2 | * This program is free software; you can redistribute it and/or | |
| 3 | * modify it under the terms of the GNU General Public License | |
| 4 | * as published by the Free Software Foundation; version 2 | |
| 5 | * of the License. | |
| 6 | * | |
| 7 | */ | |
| 8 | ||
| 9 | #include <linux/linkage.h> | |
| 10 | #include <asm/alternative-asm.h> | |
| 11 | #include <asm/frame.h> | |
| 12 | #include <asm/dwarf2.h> | |
| 13 | ||
| 14 | ||
| 15 | .text | |
| 16 | ||
| 17 | /* | |
| 18 | * Inputs: | |
| 19 | * %esi : memory location to compare | |
| 20 | * %eax : low 32 bits of old value | |
| 21 | * %edx : high 32 bits of old value | |
| 22 | * %ebx : low 32 bits of new value | |
| 23 | * %ecx : high 32 bits of new value | |
| 24 | */ | |
| 25 | ENTRY(cmpxchg8b_emu) | |
| 26 | CFI_STARTPROC | |
| 27 | ||
| 28 | # | |
| 29 | # Emulate 'cmpxchg8b (%esi)' on UP except we don't | |
| 30 | # set the whole ZF thing (caller will just compare | |
| 31 | # eax:edx with the expected value) | |
| 32 | # | |
| 33 | cmpxchg8b_emu: | |
| 34 | pushfl | |
| 35 | cli | |
| 36 | ||
| 37 | cmpl (%esi), %eax | |
| 38 | jne not_same | |
| 39 | cmpl 4(%esi), %edx | |
| 40 | jne half_same | |
| 41 | ||
| 42 | movl %ebx, (%esi) | |
| 43 | movl %ecx, 4(%esi) | |
| 44 | ||
| 45 | popfl | |
| 46 | ret | |
| 47 | ||
| 48 | not_same: | |
| 49 | movl (%esi), %eax | |
| 50 | half_same: | |
| 51 | movl 4(%esi), %edx | |
| 52 | ||
| 53 | popfl | |
| 54 | ret | |
| 55 | ||
| 56 | CFI_ENDPROC | |
| 57 | ENDPROC(cmpxchg8b_emu) |