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Tip revision: cbd9c883696da72b2b1f03f909dbacc04bbf8b58 authored by Linus Torvalds on 16 January 2008, 04:22:48 UTC
Linux 2.6.24-rc8
Tip revision: cbd9c88
rwlock_64.S
/* Slow paths of read/write spinlocks. */

#include <linux/linkage.h>
#include <asm/rwlock.h>
#include <asm/alternative-asm.h>
#include <asm/dwarf2.h>

/* rdi:	pointer to rwlock_t */
ENTRY(__write_lock_failed)
	CFI_STARTPROC
	LOCK_PREFIX
	addl $RW_LOCK_BIAS,(%rdi)
1:	rep
	nop
	cmpl $RW_LOCK_BIAS,(%rdi)
	jne 1b
	LOCK_PREFIX
	subl $RW_LOCK_BIAS,(%rdi)
	jnz  __write_lock_failed
	ret
	CFI_ENDPROC
END(__write_lock_failed)

/* rdi:	pointer to rwlock_t */
ENTRY(__read_lock_failed)
	CFI_STARTPROC
	LOCK_PREFIX
	incl (%rdi)
1:	rep
	nop
	cmpl $1,(%rdi)
	js 1b
	LOCK_PREFIX
	decl (%rdi)
	js __read_lock_failed
	ret
	CFI_ENDPROC
END(__read_lock_failed)
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