Re: [PATCH 7/8] ACPI: property: Skip MIPI property table without "mipi-img" prefix

Sakari Ailus
2023-01-20T12:07:49Z

On Thu, Jan 19, 2023 at 06:11:11PM +0200, Andy Shevchenko wrote:
> On Thu, Jan 19, 2023 at 06:09:26PM +0200, Andy Shevchenko wrote:
> > On Thu, Jan 19, 2023 at 03:51:33PM +0000, Sakari Ailus wrote:
> > > On Tue, Jan 17, 2023 at 05:29:54PM +0200, Andy Shevchenko wrote:
> > > > On Tue, Jan 17, 2023 at 02:22:43PM +0200, Sakari Ailus wrote:
>
> ...
>
> > > > > + if (memcmp(elements[0].string.pointer, MIPI_IMG_PREFIX,
> > > > > + sizeof(MIPI_IMG_PREFIX) - 1))
> > > >
> > > > str_has_prefix()
> > >
> > > str_has_prefix() calls strlen() on prefix on every call. sizeof() will
> > > generate much less code --- it's just a number.
> >
> > Have you tried that? Because the strlen() over const string literals will be
> > optimized away on compilation time.
>
> Probably that's the reason behind __always_inline for that function.

For str_has_prefix() the reason probably is that inlining that function
generates less code than when not doing so.

--
Sakari Ailus