Re: [PATCH 2/5] Blackfin arch: SMP supporting patchset: Blackfin header files and machine common code

Bryan Wu
2008-11-19T07:44:59Z

On Wed, Nov 19, 2008 at 3:05 PM, Nick Piggin <nickpiggin@yahoo.com.au> wrote:
> On Wednesday 19 November 2008 17:56, Andrew Morton wrote:
>> On Tue, 18 Nov 2008 17:05:05 +0800 Bryan Wu <cooloney@kernel.org> wrote:
>
>> > +#define smp_mb__before_clear_bit() barrier()
>> > +#define smp_mb__after_clear_bit() barrier()
>> > +
>> > +static inline void __set_bit(int nr, volatile unsigned long *addr)
>> > +{
>> > + int *a = (int *)addr;
>> > + int mask;
>> > +
>> > + a += nr >> 5;
>> > + mask = 1 << (nr & 0x1f);
>> > + *a |= mask;
>> > +}
>> > +
>> > +static inline void __clear_bit(int nr, volatile unsigned long *addr)
>> > +{
>> > + int *a = (int *)addr;
>> > + int mask;
>> > +
>> > + a += nr >> 5;
>> > + mask = 1 << (nr & 0x1f);
>> > + *a &= ~mask;
>> > +}
>> > +
>> > +static inline void __change_bit(int nr, volatile unsigned long *addr)
>> > +{
>> > + int mask;
>> > + unsigned long *ADDR = (unsigned long *)addr;
>> > +
>> > + ADDR += nr >> 5;
>> > + mask = 1 << (nr & 31);
>> > + *ADDR ^= mask;
>> > +}
>>
>> I'm surprised there isn't any generic code which can be used for the above.
>
> include/asm-generic/bitops/non-atomic.h
>
>
>> > ...
>>
>> Gad what a lot of code. I don't think I have time to read it all, sorry.
>
> :) I don't know who is expected to. Cc'ing linux-arch for something
> like this might attract some helpful comments.

Yeah, I posted it to linux-arch.
Thanks
-Bryan