Re: [RFC][PATCH 19/24] s390: Provide atomic_{or,xor,and}

From: Heiko Carstens
Date: Fri Jul 10 2015 - 03:17:29 EST


On Thu, Jul 09, 2015 at 07:29:14PM +0200, Peter Zijlstra wrote:
> Implement atomic logic ops -- atomic_{or,xor,and}.
>
> These will replace the atomic_{set,clear}_mask functions that are
> available on some archs.
>
> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
> ---
> arch/s390/include/asm/atomic.h | 45 ++++++++++++++++++++++++++++-------------
> 1 file changed, 31 insertions(+), 14 deletions(-)
>
> --- a/arch/s390/include/asm/atomic.h
> +++ b/arch/s390/include/asm/atomic.h
> @@ -28,6 +28,7 @@
> #define __ATOMIC_AND "lan"
> #define __ATOMIC_ADD "laa"
> #define __ATOMIC_BARRIER "bcr 14,0\n"
> +#define __ATOMIC_XOR "lax"
>
> #define __ATOMIC_LOOP(ptr, op_val, op_string, __barrier) \
> ({ \
> @@ -50,6 +51,7 @@
> #define __ATOMIC_AND "nr"
> #define __ATOMIC_ADD "ar"
> #define __ATOMIC_BARRIER "\n"
> +#define __ATOMIC_XOR "xr"

Would you mind moving the two XOR define above the BARRIER?
Just to keep it consistent with ATOMIC64 stuff within this patch ;)

> #define __ATOMIC_LOOP(ptr, op_val, op_string, __barrier) \
> ({ \
> @@ -118,14 +120,26 @@ static inline void atomic_add(int i, ato
> #define atomic_dec_return(_v) atomic_sub_return(1, _v)
> #define atomic_dec_and_test(_v) (atomic_sub_return(1, _v) == 0)
>
> -static inline void atomic_clear_mask(unsigned int mask, atomic_t *v)
> +#define ATOMIC_OP(op, OP) \
> +static inline void atomic_##op(int i, atomic_t *v) \
> +{ \
> + __ATOMIC_LOOP(v, i, __ATOMIC_##OP, __ATOMIC_NO_BARRIER); \
> +}
> +
> +ATOMIC_OP(and, AND)
> +ATOMIC_OP(or, OR)
> +ATOMIC_OP(xor, XOR)
> +
> +#undef ATOMIC_OP
> +
> +static inline __deprecated void atomic_clear_mask(unsigned int mask, atomic_t *v)
> {
> - __ATOMIC_LOOP(v, ~mask, __ATOMIC_AND, __ATOMIC_NO_BARRIER);
> + atomic_and(~mask, v);
> }
>
> -static inline void atomic_set_mask(unsigned int mask, atomic_t *v)
> +static inline __deprecated void atomic_set_mask(unsigned int mask, atomic_t *v)
> {
> - __ATOMIC_LOOP(v, mask, __ATOMIC_OR, __ATOMIC_NO_BARRIER);
> + atomic_or(mask, v);
> }

If you insist on the __deprecated (no problem with that), I'd like to apply
your patch to the s390 tree so I can convert all users.
I would like to avoid to see tons of warnings.

Besides that:

Acked-by: Heiko Carstens <heiko.carstens@xxxxxxxxxx>

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