Re: [PATCH] padata: Use RCU when fetching pd from do_serial

From: Herbert Xu
Date: Tue Jul 16 2019 - 09:18:21 EST


On Tue, Jul 16, 2019 at 03:15:20PM +0200, Peter Zijlstra wrote:
>
> > @@ -367,7 +368,7 @@ void padata_do_serial(struct padata_priv *padata)
> > struct parallel_data *pd;
> > int reorder_via_wq = 0;
> >
> > - pd = padata->pd;
> > + pd = rcu_dereference_bh(padata->inst->pd);
> >
> > cpu = get_cpu();
> >
>
> That's weird for not having a matching assign and lacking comments to
> explain that.

There is a matching rcu_assign_pointer. But we should add some
RCU markers.

Or perhaps you're misreading the level of indirections :)

Cheers,
--
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
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