diff options
author | Ingo Molnar <mingo@elte.hu> | 2009-10-13 09:31:28 +0200 |
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committer | Ingo Molnar <mingo@elte.hu> | 2009-10-13 09:31:34 +0200 |
commit | 9dbdd6c41c12fb42ee7188eafa7e1917b192af3a (patch) | |
tree | 06a9eb894bc976c5c20e84ccd74fd82b9b71aed4 /arch/x86/lib/cmpxchg8b_emu.S | |
parent | 7a693d3f0d10f978ebdf3082c41404ab97106567 (diff) | |
parent | 161291396e76e0832c08f617eb9bd364d1648148 (diff) |
Merge commit 'v2.6.32-rc4' into perf/core
Merge reason: we were on an -rc1 base, merge up to -rc4.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/lib/cmpxchg8b_emu.S')
-rw-r--r-- | arch/x86/lib/cmpxchg8b_emu.S | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/arch/x86/lib/cmpxchg8b_emu.S b/arch/x86/lib/cmpxchg8b_emu.S new file mode 100644 index 00000000000..828cb710dec --- /dev/null +++ b/arch/x86/lib/cmpxchg8b_emu.S @@ -0,0 +1,57 @@ +/* + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; version 2 + * of the License. + * + */ + +#include <linux/linkage.h> +#include <asm/alternative-asm.h> +#include <asm/frame.h> +#include <asm/dwarf2.h> + + +.text + +/* + * Inputs: + * %esi : memory location to compare + * %eax : low 32 bits of old value + * %edx : high 32 bits of old value + * %ebx : low 32 bits of new value + * %ecx : high 32 bits of new value + */ +ENTRY(cmpxchg8b_emu) +CFI_STARTPROC + +# +# Emulate 'cmpxchg8b (%esi)' on UP except we don't +# set the whole ZF thing (caller will just compare +# eax:edx with the expected value) +# +cmpxchg8b_emu: + pushfl + cli + + cmpl (%esi), %eax + jne not_same + cmpl 4(%esi), %edx + jne half_same + + movl %ebx, (%esi) + movl %ecx, 4(%esi) + + popfl + ret + + not_same: + movl (%esi), %eax + half_same: + movl 4(%esi), %edx + + popfl + ret + +CFI_ENDPROC +ENDPROC(cmpxchg8b_emu) |