RE: [PATCH] /dev/zero: also implement ->read

David Laight
2020-09-03T21:35:07Z

From: Christophe Leroy
>
>
> Le 03/09/2020 à 17:59, Christoph Hellwig a écrit :
> > Christophe reported a major speedup due to avoiding the iov_iter
> > overhead, so just add this trivial function. Note that /dev/zero
> > already implements both an iter and non-iter writes so this just
> > makes it more symmetric.
> >
> > Christophe Leroy <christophe.leroy@csgroup.eu>
> > Signed-off-by: Christoph Hellwig <hch@lst.de>
>
> Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu>

Any idea what has happened to make the 'iter' version so bad?

David

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