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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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