Messages in this thread | | | Date | Fri, 3 Feb 2023 13:27:17 +0200 | From | 'Andy Shevchenko' <> | Subject | Re: [PATCH v1 1/1] usb: gadget: configfs: Use memcpy_and_pad() |
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On Thu, Feb 02, 2023 at 10:21:09PM +0000, David Laight wrote: > From: Andy Shevchenko > > Sent: 02 February 2023 15:18 > > > > Instead of zeroing some memory and then copying data in part or all of it, > > use memcpy_and_pad(). > > This avoids writing some memory twice and should save a few cycles. > > Maybe, maybe not. > It rather depends on the lengths involved (the code doesn't seem to be in the > main tree). > > The cost of the conditionals and the misaligned length/start for the > memset() could easily overwhelm any apparent saving. > > A memset() of a constant whole number of words is going to be significantly > faster than the partial one.
Then you can put some (little I suppose) efforts in optimizing memcpy_and_pad() once for all, no?
-- With Best Regards, Andy Shevchenko
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