Re: [PATCH] include/uapi/linux/swab: Fix potentially missing __always_inline

[Florian Fainelli]

On 10/6/22 13:33, Florian Fainelli wrote:
> Hi Nathan,
>
> On 9/28/2022 3:36 PM, Nathan Chancellor wrote:
> > Hi Florian,
> >
> > On Tue, Sep 27, 2022 at 02:52:56PM -0700, Florian Fainelli wrote:
> > > From: Matt Redfearn <matt.redfearn@xxxxxxxx>
> > >
> > > Commit bc27fb68aaad ("include/uapi/linux/byteorder, swab: force inlining
> > > of some byteswap operations") added __always_inline to swab functions
> > > and commit 283d75737837 ("uapi/linux/stddef.h: Provide 
> > > __always_inline to
> > > userspace headers") added a definition of __always_inline for use in
> > > exported headers when the kernel's compiler.h is not available.
> > >
> > > However, since swab.h does not include stddef.h, if the header soup does
> > > not indirectly include it, the definition of __always_inline is missing,
> > > resulting in a compilation failure, which was observed compiling the
> > > perf tool using exported headers containing this commit:
> > >
> > > In file included from /usr/include/linux/byteorder/little_endian.h:12:0,
> > >                   from /usr/include/asm/byteorder.h:14,
> > >                   from tools/include/uapi/linux/perf_event.h:20,
> > >                   from perf.h:8,
> > >                   from builtin-bench.c:18:
> > > /usr/include/linux/swab.h:160:8: error: unknown type name 
> > > `__always_inline'
> > >   static __always_inline __u16 __swab16p(const __u16 *p)
> > >
> > > Fix this by replacing the inclusion of linux/compiler.h with
> > > linux/stddef.h to ensure that we pick up that definition if required,
> > > without relying on it's indirect inclusion. compiler.h is then included
> > > indirectly, via stddef.h.
> > >
> > > Fixes: 283d75737837 ("uapi/linux/stddef.h: Provide __always_inline to 
> > > userspace headers")
> > > Signed-off-by: Matt Redfearn <matt.redfearn@xxxxxxxx>
> > > Reviewed-by: Petr Vaněk <arkamar@xxxxxxxx>
> > > Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
> >
> > I took this through my kernel build matrix and did not see any new
> > issues.
> >
> > Tested-by: Nathan Chancellor <nathan@xxxxxxxxxx>
>
> Great thanks! Since this is really useful for kernel-headers in 
> toolchains, it would be great to get this picked up. Arnd is this 
> something that would go via your tree?

Arnd, is this a patch you can merge? Thanks
--
Florian