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>
This commit is contained in:
Takashi Yoshii 2009-01-28 09:29:13 +00:00 committed by Paul Mundt
parent 03f07876df
commit c20f326a62
1 changed files with 9 additions and 12 deletions

View File

@ -21,38 +21,36 @@
static inline void static inline void
__mutex_fastpath_lock(atomic_t *count, void (*fail_fn)(atomic_t *)) __mutex_fastpath_lock(atomic_t *count, void (*fail_fn)(atomic_t *))
{ {
int __ex_flag, __res; int __done, __res;
__asm__ __volatile__ ( __asm__ __volatile__ (
"movli.l @%2, %0 \n" "movli.l @%2, %0 \n"
"add #-1, %0 \n" "add #-1, %0 \n"
"movco.l %0, @%2 \n" "movco.l %0, @%2 \n"
"movt %1 \n" "movt %1 \n"
: "=&z" (__res), "=&r" (__ex_flag) : "=&z" (__res), "=&r" (__done)
: "r" (&(count)->counter) : "r" (&(count)->counter)
: "t"); : "t");
__res |= !__ex_flag; if (unlikely(!__done || __res != 0))
if (unlikely(__res != 0))
fail_fn(count); fail_fn(count);
} }
static inline int static inline int
__mutex_fastpath_lock_retval(atomic_t *count, int (*fail_fn)(atomic_t *)) __mutex_fastpath_lock_retval(atomic_t *count, int (*fail_fn)(atomic_t *))
{ {
int __ex_flag, __res; int __done, __res;
__asm__ __volatile__ ( __asm__ __volatile__ (
"movli.l @%2, %0 \n" "movli.l @%2, %0 \n"
"add #-1, %0 \n" "add #-1, %0 \n"
"movco.l %0, @%2 \n" "movco.l %0, @%2 \n"
"movt %1 \n" "movt %1 \n"
: "=&z" (__res), "=&r" (__ex_flag) : "=&z" (__res), "=&r" (__done)
: "r" (&(count)->counter) : "r" (&(count)->counter)
: "t"); : "t");
__res |= !__ex_flag; if (unlikely(!__done || __res != 0))
if (unlikely(__res != 0))
__res = fail_fn(count); __res = fail_fn(count);
return __res; return __res;
@ -61,19 +59,18 @@ __mutex_fastpath_lock_retval(atomic_t *count, int (*fail_fn)(atomic_t *))
static inline void static inline void
__mutex_fastpath_unlock(atomic_t *count, void (*fail_fn)(atomic_t *)) __mutex_fastpath_unlock(atomic_t *count, void (*fail_fn)(atomic_t *))
{ {
int __ex_flag, __res; int __done, __res;
__asm__ __volatile__ ( __asm__ __volatile__ (
"movli.l @%2, %0 \n\t" "movli.l @%2, %0 \n\t"
"add #1, %0 \n\t" "add #1, %0 \n\t"
"movco.l %0, @%2 \n\t" "movco.l %0, @%2 \n\t"
"movt %1 \n\t" "movt %1 \n\t"
: "=&z" (__res), "=&r" (__ex_flag) : "=&z" (__res), "=&r" (__done)
: "r" (&(count)->counter) : "r" (&(count)->counter)
: "t"); : "t");
__res |= !__ex_flag; if (unlikely(!__done || __res <= 0))
if (unlikely(__res <= 0))
fail_fn(count); fail_fn(count);
} }