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

David Laight
2020-09-07T08:18:25Z

From: Christophe Leroy
> Sent: 07 September 2020 05:44
...
> If you are talking about the tests around the set_fs series from
> Christoph, I identified that the degradation was linked to
> CONFIG_STACKPROTECTOR_STRONG being selected by default, which provides
> unreliable results from one patch to another, GCC doing some strange
> things linked to unrelated changes.
>
> With CONFIG_STACKPROTECTOR set to N, I get stable performance and no
> degradation with any of the patches of the set_fs series.

Ah I didn't spot that response going through.

Sounds like that option should be disabled if it causes that
much of a performance drop.

David

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