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SubjectRe: [PATCH 3/3] WorkStruct: Use direct assignment rather than cmpxchg()
Date
Russell King <rmk+lkml@arm.linux.org.uk> wrote:

> Incorrect. pre-v6 ARM bitops for test_and_xxx_bit() all do:
>
> save and disable irqs
> load value
> test bit
> if not in desired state, alter bit and write it back
> restore irqs

Hmmm... ARM has two implementations. One in the header files which is what I
consulted when writing that email:

static inline void ____atomic_set_bit(unsigned int bit, volatile unsigned long *p)
{
unsigned long flags;
unsigned long mask = 1UL << (bit & 31);

p += bit >> 5;

raw_local_irq_save(flags);
*p |= mask;
raw_local_irq_restore(flags);
}

And the other in the libs which does as you say. Why the one in the header
file at all?

David
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