acrn-kernel/arch/x86/lib/rwlock_64.S

39 lines
646 B
ArmAsm

/* 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)