sh: Fix up T-bit error handling in SH-4A mutex fastpath.
This corrects a deadlock encountered on ap325 in the cases where the mutex is contended and the slow-path needs to be fallen back upon. Signed-off-by: Takashi YOSHII <yoshii.takashi@renesas.com> Signed-off-by: Kuninori Morimoto <morimoto.kuninori@renesas.com> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
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					 1 changed files with 9 additions and 12 deletions
				
			
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			@ -21,38 +21,36 @@
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static inline void
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__mutex_fastpath_lock(atomic_t *count, void (*fail_fn)(atomic_t *))
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{
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	int __ex_flag, __res;
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	int __done, __res;
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	__asm__ __volatile__ (
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		"movli.l	@%2, %0	\n"
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		"add		#-1, %0	\n"
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		"movco.l	%0, @%2	\n"
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		"movt		%1	\n"
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		: "=&z" (__res), "=&r" (__ex_flag)
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		: "=&z" (__res), "=&r" (__done)
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		: "r" (&(count)->counter)
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		: "t");
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	__res |= !__ex_flag;
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	if (unlikely(__res != 0))
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	if (unlikely(!__done || __res != 0))
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		fail_fn(count);
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}
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static inline int
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__mutex_fastpath_lock_retval(atomic_t *count, int (*fail_fn)(atomic_t *))
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{
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	int __ex_flag, __res;
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	int __done, __res;
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	__asm__ __volatile__ (
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		"movli.l	@%2, %0	\n"
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		"add		#-1, %0	\n"
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		"movco.l	%0, @%2	\n"
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		"movt		%1	\n"
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		: "=&z" (__res), "=&r" (__ex_flag)
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		: "=&z" (__res), "=&r" (__done)
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		: "r" (&(count)->counter)
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		: "t");
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	__res |= !__ex_flag;
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	if (unlikely(__res != 0))
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	if (unlikely(!__done || __res != 0))
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		__res = fail_fn(count);
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	return __res;
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			@ -61,19 +59,18 @@ __mutex_fastpath_lock_retval(atomic_t *count, int (*fail_fn)(atomic_t *))
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static inline void
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__mutex_fastpath_unlock(atomic_t *count, void (*fail_fn)(atomic_t *))
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{
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	int __ex_flag, __res;
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	int __done, __res;
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	__asm__ __volatile__ (
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		"movli.l	@%2, %0	\n\t"
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		"add		#1, %0	\n\t"
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		"movco.l	%0, @%2 \n\t"
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		"movt		%1	\n\t"
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		: "=&z" (__res), "=&r" (__ex_flag)
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		: "=&z" (__res), "=&r" (__done)
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		: "r" (&(count)->counter)
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		: "t");
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	__res |= !__ex_flag;
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	if (unlikely(__res <= 0))
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	if (unlikely(!__done || __res <= 0))
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		fail_fn(count);
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}
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