[SPARC64]: Fix futex_atomic_cmpxchg_inatomic implementation. (c7fed9d7) · Commits · 戴 / test

I copied the logic from ll/sc arch implementations, but that was wrong and makes no sense at all. Just do a straight compare-exchange instruction, just like x86. Based upon bug reports from Dennis Gilmore and Fabio Massimo. Signed-off-by:

David S. Miller <davem@davemloft.net>

include/asm-sparc64/futex.h

+8 −10

Original line number	Diff line number	Diff line
		@@ -87,24 +87,22 @@ static inline int
		futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval)
		{
		__asm__ __volatile__(
		"\n1: lduwa [%2] %%asi, %0\n"
		"2: casa [%2] %%asi, %0, %1\n"
		"3:\n"
		"\n1: casa [%3] %%asi, %2, %0\n"
		"2:\n"
		" .section .fixup,#alloc,#execinstr\n"
		" .align 4\n"
		"4: ba 3b\n"
		" mov %3, %0\n"
		"3: ba 2b\n"
		" mov %4, %0\n"
		" .previous\n"
		" .section __ex_table,\"a\"\n"
		" .align 4\n"
		" .word 1b, 4b\n"
		" .word 2b, 4b\n"
		" .word 1b, 3b\n"
		" .previous\n"
		: "=&r" (oldval)
		: "r" (newval), "r" (uaddr), "i" (-EFAULT)
		: "=r" (newval)
		: "0" (newval), "r" (oldval), "r" (uaddr), "i" (-EFAULT)
		: "memory");

		return oldval;
		return newval;
		}

		#endif /* !(_SPARC64_FUTEX_H) */

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