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SubjectRe: [PATCH 2/5] atomic: introduce atomic_inc_not_zero
Hi,

On Thu, 15 Sep 2005, Nick Piggin wrote:

> Or here is possible pseudo code for an architecture with ll/sc
> instructions:
>
> do {
> tmp = load_locked(v);
> if (!tmp)
> break;
> tmp++;
> } while (!store_cond(v, tmp));
>
> return tmp;
>
> As opposed to using the cmpxchg version, which would have more
> loads and conditional branches, AFAIKS.

I'd prefer to generalize this construct, than polluting atomic.h with all
kinds of esoteric atomic operations.
So you would get:

do {
old = atomic_load_locked(v);
if (!old)
break;
new = old + 1;
} while (!atomic_store_lock(v, old, new));
bye, Roman
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