Wang Jinchao <wangjinchao@xxxxxxxxxxx> wrote:
>
> diff --git a/kernel/padata.c b/kernel/padata.c
> index 222d60195de6..79d04a97ded6 100644
> --- a/kernel/padata.c
> +++ b/kernel/padata.c
> @@ -1102,12 +1102,16 @@ EXPORT_SYMBOL(padata_alloc_shell);
> */
> void padata_free_shell(struct padata_shell *ps)
> {
> + struct parallel_data *pd;
> +
> if (!ps)
> return;
>
> mutex_lock(&ps->pinst->lock);
> list_del(&ps->list);
> - padata_free_pd(rcu_dereference_protected(ps->pd, 1));
> + pd = rcu_dereference_protected(ps->pd, 1);
> + if (refcount_dec_and_test(&pd->refcnt))
> + padata_free_pd(rcu_dereference_protected(ps->pd, 1));
Why is this dereferencing ps->pd again after the refcount_dec_and_test?
If this is necessary please explain it in the code because it is not
at all obvious.
Thanks,
--
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
