Re: [PATCH 12/20] arch,metag: Fold atomic_ops

From: James Hogan
Date: Tue May 13 2014 - 06:06:58 EST


On 08/05/14 14:58, Peter Zijlstra wrote:
> 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: James Hogan <james.hogan@xxxxxxxxxx>
> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx>

Looks good and disassembly is unchanged for both lnkget/lnkset and lock1.

Acked-by: James Hogan <james.hogan@xxxxxxxxxx>

Let me know if you want this patch taken separately through the metag tree.

Thanks
James

> ---
> arch/metag/include/asm/atomic_lnkget.h | 121 ++++++++++++---------------------
> arch/metag/include/asm/atomic_lock1.h | 76 ++++++++------------
> 2 files changed, 77 insertions(+), 120 deletions(-)
>
> Index: linux-2.6/arch/metag/include/asm/atomic_lnkget.h
> ===================================================================
> --- linux-2.6.orig/arch/metag/include/asm/atomic_lnkget.h
> +++ linux-2.6/arch/metag/include/asm/atomic_lnkget.h
> @@ -27,85 +27,56 @@ static inline int atomic_read(const atom
> return temp;
> }
>
> -static inline void atomic_add(int i, atomic_t *v)
> -{
> - int temp;
> -
> - asm volatile (
> - "1: LNKGETD %0, [%1]\n"
> - " ADD %0, %0, %2\n"
> - " LNKSETD [%1], %0\n"
> - " DEFR %0, TXSTAT\n"
> - " ANDT %0, %0, #HI(0x3f000000)\n"
> - " CMPT %0, #HI(0x02000000)\n"
> - " BNZ 1b\n"
> - : "=&d" (temp)
> - : "da" (&v->counter), "bd" (i)
> - : "cc");
> +#define ATOMIC_OP(op) \
> +static inline void atomic_##op(int i, atomic_t *v) \
> +{ \
> + int temp; \
> + \
> + asm volatile ( \
> + "1: LNKGETD %0, [%1]\n" \
> + " " #op " %0, %0, %2\n" \
> + " LNKSETD [%1], %0\n" \
> + " DEFR %0, TXSTAT\n" \
> + " ANDT %0, %0, #HI(0x3f000000)\n" \
> + " CMPT %0, #HI(0x02000000)\n" \
> + " BNZ 1b\n" \
> + : "=&d" (temp) \
> + : "da" (&v->counter), "bd" (i) \
> + : "cc"); \
> +} \
> +
> +#define ATOMIC_OP_RETURN(op) \
> +static inline int atomic_##op##_return(int i, atomic_t *v) \
> +{ \
> + int result, temp; \
> + \
> + smp_mb(); \
> + \
> + asm volatile ( \
> + "1: LNKGETD %1, [%2]\n" \
> + " " #op " %1, %1, %3\n" \
> + " LNKSETD [%2], %1\n" \
> + " DEFR %0, TXSTAT\n" \
> + " ANDT %0, %0, #HI(0x3f000000)\n" \
> + " CMPT %0, #HI(0x02000000)\n" \
> + " BNZ 1b\n" \
> + : "=&d" (temp), "=&da" (result) \
> + : "da" (&v->counter), "bd" (i) \
> + : "cc"); \
> + \
> + smp_mb(); \
> + \
> + return result; \
> }
>
> -static inline void atomic_sub(int i, atomic_t *v)
> -{
> - int temp;
> -
> - asm volatile (
> - "1: LNKGETD %0, [%1]\n"
> - " SUB %0, %0, %2\n"
> - " LNKSETD [%1], %0\n"
> - " DEFR %0, TXSTAT\n"
> - " ANDT %0, %0, #HI(0x3f000000)\n"
> - " CMPT %0, #HI(0x02000000)\n"
> - " BNZ 1b\n"
> - : "=&d" (temp)
> - : "da" (&v->counter), "bd" (i)
> - : "cc");
> -}
> -
> -static inline int atomic_add_return(int i, atomic_t *v)
> -{
> - int result, temp;
> -
> - smp_mb();
> -
> - asm volatile (
> - "1: LNKGETD %1, [%2]\n"
> - " ADD %1, %1, %3\n"
> - " LNKSETD [%2], %1\n"
> - " DEFR %0, TXSTAT\n"
> - " ANDT %0, %0, #HI(0x3f000000)\n"
> - " CMPT %0, #HI(0x02000000)\n"
> - " BNZ 1b\n"
> - : "=&d" (temp), "=&da" (result)
> - : "da" (&v->counter), "bd" (i)
> - : "cc");
> +#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op)
>
> - smp_mb();
> +ATOMIC_OPS(add)
> +ATOMIC_OPS(sub)
>
> - return result;
> -}
> -
> -static inline int atomic_sub_return(int i, atomic_t *v)
> -{
> - int result, temp;
> -
> - smp_mb();
> -
> - asm volatile (
> - "1: LNKGETD %1, [%2]\n"
> - " SUB %1, %1, %3\n"
> - " LNKSETD [%2], %1\n"
> - " DEFR %0, TXSTAT\n"
> - " ANDT %0, %0, #HI(0x3f000000)\n"
> - " CMPT %0, #HI(0x02000000)\n"
> - " BNZ 1b\n"
> - : "=&d" (temp), "=&da" (result)
> - : "da" (&v->counter), "bd" (i)
> - : "cc");
> -
> - smp_mb();
> -
> - return result;
> -}
> +#undef ATOMIC_OPS
> +#undef ATOMIC_OP_RETURN
> +#undef ATOMIC_OP
>
> static inline void atomic_clear_mask(unsigned int mask, atomic_t *v)
> {
> Index: linux-2.6/arch/metag/include/asm/atomic_lock1.h
> ===================================================================
> --- linux-2.6.orig/arch/metag/include/asm/atomic_lock1.h
> +++ linux-2.6/arch/metag/include/asm/atomic_lock1.h
> @@ -37,55 +37,41 @@ static inline int atomic_set(atomic_t *v
> return i;
> }
>
> -static inline void atomic_add(int i, atomic_t *v)
> -{
> - unsigned long flags;
> -
> - __global_lock1(flags);
> - fence();
> - v->counter += i;
> - __global_unlock1(flags);
> +#define ATOMIC_OP(op, c_op) \
> +static inline void atomic_##op(int i, atomic_t *v) \
> +{ \
> + unsigned long flags; \
> + \
> + __global_lock1(flags); \
> + fence(); \
> + v->counter c_op i; \
> + __global_unlock1(flags); \
> +} \
> +
> +#define ATOMIC_OP_RETURN(op, c_op) \
> +static inline int atomic_##op##_return(int i, atomic_t *v) \
> +{ \
> + unsigned long result; \
> + unsigned long flags; \
> + \
> + __global_lock1(flags); \
> + result = v->counter; \
> + result c_op i; \
> + fence(); \
> + v->counter = result; \
> + __global_unlock1(flags); \
> + \
> + return result; \
> }
>
> -static inline void atomic_sub(int i, atomic_t *v)
> -{
> - unsigned long flags;
> -
> - __global_lock1(flags);
> - fence();
> - v->counter -= i;
> - __global_unlock1(flags);
> -}
> -
> -static inline int atomic_add_return(int i, atomic_t *v)
> -{
> - unsigned long result;
> - unsigned long flags;
> +#define ATOMIC_OPS(op, c_op) ATOMIC_OP(op, c_op) ATOMIC_OP_RETURN(op, c_op)
>
> - __global_lock1(flags);
> - result = v->counter;
> - result += i;
> - fence();
> - v->counter = result;
> - __global_unlock1(flags);
> +ATOMIC_OPS(add, +=)
> +ATOMIC_OPS(sub, -=)
>
> - return result;
> -}
> -
> -static inline int atomic_sub_return(int i, atomic_t *v)
> -{
> - unsigned long result;
> - unsigned long flags;
> -
> - __global_lock1(flags);
> - result = v->counter;
> - result -= i;
> - fence();
> - v->counter = result;
> - __global_unlock1(flags);
> -
> - return result;
> -}
> +#undef ATOMIC_OPS
> +#undef ATOMIC_OP_RETURN
> +#undef ATOMIC_OP
>
> static inline void atomic_clear_mask(unsigned int mask, atomic_t *v)
> {
>
>
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