Re: [PATCH] target/file: don't zero iter before iov_iter_bvec

From: Pavel Begunkov
Date: Sat Jan 09 2021 - 16:30:24 EST


On 09/01/2021 20:52, Chaitanya Kulkarni wrote:
> On 1/9/21 12:40, Pavel Begunkov wrote:
>> I expect you won't find any, but such little things can pile up
>> into a not-easy-to-spot overhead over time.
>
> That is what I suspected with the resulting assembly. The commit log
> needs to document that there is no direct impact on the performance

It's obvious that 3-4 extra mov $0 off(%reg) won't change performance
but still hasn't been formally confirmed ...

> which can be seen with this patch, but this is nice to have

... so if you don't mind, I won't be resending just for that.

--
Pavel Begunkov