[PATCH 19/20] arch,xtensa: Fold atomic_ops

From: Peter Zijlstra
Date: Thu May 08 2014 - 10:02:49 EST


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.

Cc: Chris Zankel <chris@xxxxxxxxxx>
Cc: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Max Filippov <jcmvbkbc@xxxxxxxxx>
Signed-off-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
---
arch/xtensa/include/asm/atomic.h | 231 +++++++++++++--------------------------
1 file changed, 81 insertions(+), 150 deletions(-)

Index: linux-2.6/arch/xtensa/include/asm/atomic.h
===================================================================
--- linux-2.6.orig/arch/xtensa/include/asm/atomic.h
+++ linux-2.6/arch/xtensa/include/asm/atomic.h
@@ -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
+#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; \
}

-/**
- * 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;
+#else /* 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"
- : "=&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 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; \
}

-/*
- * 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;
+#endif /* XCHAL_HAVE_S32C1I */

- __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"
- );
+#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op)

- return vval;
-#endif
-}
+ATOMIC_OPS(add)
+ATOMIC_OPS(sub)

-static inline int atomic_sub_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"
- " 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"
- );
-
- 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"
- );
-
- 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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