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locking,arch,xtensa: Fold atomic_ops
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Many of the atomic op implementations are the same except for one
instruction; fold the lot into a few CPP macros and reduce LoC.

This also prepares for easy addition of new ops.

Signed-off-by: Peter Zijlstra <[email protected]>
Cc: Chris Zankel <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Max Filippov <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Paul E. McKenney <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
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Peter Zijlstra authored and Ingo Molnar committed Aug 14, 2014
1 parent 4f3316c commit d4608dd
Showing 1 changed file with 82 additions and 151 deletions.
233 changes: 82 additions & 151 deletions arch/xtensa/include/asm/atomic.h
Original file line number Diff line number Diff line change
Expand Up @@ -58,165 +58,96 @@
*/
#define atomic_set(v,i) ((v)->counter = (i))

/**
* atomic_add - add integer to atomic variable
* @i: integer value to add
* @v: pointer of type atomic_t
*
* Atomically adds @i to @v.
*/
static inline void atomic_add(int i, atomic_t * v)
{
#if XCHAL_HAVE_S32C1I
unsigned long tmp;
int result;

__asm__ __volatile__(
"1: l32i %1, %3, 0\n"
" wsr %1, scompare1\n"
" add %0, %1, %2\n"
" s32c1i %0, %3, 0\n"
" bne %0, %1, 1b\n"
: "=&a" (result), "=&a" (tmp)
: "a" (i), "a" (v)
: "memory"
);
#else
unsigned int vval;

__asm__ __volatile__(
" rsil a15, "__stringify(LOCKLEVEL)"\n"
" l32i %0, %2, 0\n"
" add %0, %0, %1\n"
" s32i %0, %2, 0\n"
" wsr a15, ps\n"
" rsync\n"
: "=&a" (vval)
: "a" (i), "a" (v)
: "a15", "memory"
);
#endif
}

/**
* atomic_sub - subtract the atomic variable
* @i: integer value to subtract
* @v: pointer of type atomic_t
*
* Atomically subtracts @i from @v.
*/
static inline void atomic_sub(int i, atomic_t *v)
{
#if XCHAL_HAVE_S32C1I
unsigned long tmp;
int result;

__asm__ __volatile__(
"1: l32i %1, %3, 0\n"
" wsr %1, scompare1\n"
" sub %0, %1, %2\n"
" s32c1i %0, %3, 0\n"
" bne %0, %1, 1b\n"
: "=&a" (result), "=&a" (tmp)
: "a" (i), "a" (v)
: "memory"
);
#else
unsigned int vval;

__asm__ __volatile__(
" rsil a15, "__stringify(LOCKLEVEL)"\n"
" l32i %0, %2, 0\n"
" sub %0, %0, %1\n"
" s32i %0, %2, 0\n"
" wsr a15, ps\n"
" rsync\n"
: "=&a" (vval)
: "a" (i), "a" (v)
: "a15", "memory"
);
#endif
#define ATOMIC_OP(op) \
static inline void atomic_##op(int i, atomic_t * v) \
{ \
unsigned long tmp; \
int result; \
\
__asm__ __volatile__( \
"1: l32i %1, %3, 0\n" \
" wsr %1, scompare1\n" \
" " #op " %0, %1, %2\n" \
" s32c1i %0, %3, 0\n" \
" bne %0, %1, 1b\n" \
: "=&a" (result), "=&a" (tmp) \
: "a" (i), "a" (v) \
: "memory" \
); \
} \

#define ATOMIC_OP_RETURN(op) \
static inline int atomic_##op##_return(int i, atomic_t * v) \
{ \
unsigned long tmp; \
int result; \
\
__asm__ __volatile__( \
"1: l32i %1, %3, 0\n" \
" wsr %1, scompare1\n" \
" " #op " %0, %1, %2\n" \
" s32c1i %0, %3, 0\n" \
" bne %0, %1, 1b\n" \
" " #op " %0, %0, %2\n" \
: "=&a" (result), "=&a" (tmp) \
: "a" (i), "a" (v) \
: "memory" \
); \
\
return result; \
}

/*
* We use atomic_{add|sub}_return to define other functions.
*/

static inline int atomic_add_return(int i, atomic_t * v)
{
#if XCHAL_HAVE_S32C1I
unsigned long tmp;
int result;

__asm__ __volatile__(
"1: l32i %1, %3, 0\n"
" wsr %1, scompare1\n"
" add %0, %1, %2\n"
" s32c1i %0, %3, 0\n"
" bne %0, %1, 1b\n"
" add %0, %0, %2\n"
: "=&a" (result), "=&a" (tmp)
: "a" (i), "a" (v)
: "memory"
);

return result;
#else
unsigned int vval;

__asm__ __volatile__(
" rsil a15,"__stringify(LOCKLEVEL)"\n"
" l32i %0, %2, 0\n"
" add %0, %0, %1\n"
" s32i %0, %2, 0\n"
" wsr a15, ps\n"
" rsync\n"
: "=&a" (vval)
: "a" (i), "a" (v)
: "a15", "memory"
);

return vval;
#endif
#else /* XCHAL_HAVE_S32C1I */

#define ATOMIC_OP(op) \
static inline void atomic_##op(int i, atomic_t * v) \
{ \
unsigned int vval; \
\
__asm__ __volatile__( \
" rsil a15, "__stringify(LOCKLEVEL)"\n"\
" l32i %0, %2, 0\n" \
" " #op " %0, %0, %1\n" \
" s32i %0, %2, 0\n" \
" wsr a15, ps\n" \
" rsync\n" \
: "=&a" (vval) \
: "a" (i), "a" (v) \
: "a15", "memory" \
); \
} \

#define ATOMIC_OP_RETURN(op) \
static inline int atomic_##op##_return(int i, atomic_t * v) \
{ \
unsigned int vval; \
\
__asm__ __volatile__( \
" rsil a15,"__stringify(LOCKLEVEL)"\n" \
" l32i %0, %2, 0\n" \
" " #op " %0, %0, %1\n" \
" s32i %0, %2, 0\n" \
" wsr a15, ps\n" \
" rsync\n" \
: "=&a" (vval) \
: "a" (i), "a" (v) \
: "a15", "memory" \
); \
\
return vval; \
}

static inline int atomic_sub_return(int i, atomic_t * v)
{
#if XCHAL_HAVE_S32C1I
unsigned long tmp;
int result;
#endif /* XCHAL_HAVE_S32C1I */

__asm__ __volatile__(
"1: l32i %1, %3, 0\n"
" wsr %1, scompare1\n"
" sub %0, %1, %2\n"
" s32c1i %0, %3, 0\n"
" bne %0, %1, 1b\n"
" sub %0, %0, %2\n"
: "=&a" (result), "=&a" (tmp)
: "a" (i), "a" (v)
: "memory"
);
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op)

return result;
#else
unsigned int vval;

__asm__ __volatile__(
" rsil a15,"__stringify(LOCKLEVEL)"\n"
" l32i %0, %2, 0\n"
" sub %0, %0, %1\n"
" s32i %0, %2, 0\n"
" wsr a15, ps\n"
" rsync\n"
: "=&a" (vval)
: "a" (i), "a" (v)
: "a15", "memory"
);
ATOMIC_OPS(add)
ATOMIC_OPS(sub)

return vval;
#endif
}
#undef ATOMIC_OPS
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP

/**
* atomic_sub_and_test - subtract value from variable and test result
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