> Yes you can. cmpxchg() is atomic. Several archs implement atomic_inc() and co
> with cmpxchg() or similar.
>
> Something like:
>
> static inline struct namespace *grab_namespace(struct namespace *n)
> {
> int old = atomic_read(&n->count);
>
> while (old > 0) {
> /* attempt to increment the counter */
> old = cmpxchg(&n->count, old, old + 1);
> }
>
> return old > 0 ? n : NULL;
> }
>
Ahh OK :)
There's still the problem of cmpxchg meddling in the internals of an
atomic_t. Is that OK? Will that work on all archs?
Miklos
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