Re: [PATCH] perf beauty: Fix AT_EACCESS undeclared build error for system with kernel versions lower than v5.8

[Ian Rogers <irogers@google.com>]

On Wed, Apr 3, 2024 at 7:21 AM Arnaldo Carvalho de Melo <acme@kernel.org> wrote:
>
> On Wed, Apr 03, 2024 at 08:25:58PM +0800, Yang Jihong wrote:
> > In the environment of ubuntu20.04 (the version of kernel headers is 5.4),
> > there is an error in building perf:
> >
> >     CC      trace/beauty/fs_at_flags.o
> >   trace/beauty/fs_at_flags.c: In function ‘faccessat2__scnprintf_flags’:
> >   trace/beauty/fs_at_flags.c:35:14: error: ‘AT_EACCESS’ undeclared (first use in this function); did you mean ‘DN_ACCESS’?
> >      35 |  if (flags & AT_EACCESS) {
> >         |              ^~~~~~~~~~
> >         |              DN_ACCESS
> >   trace/beauty/fs_at_flags.c:35:14: note: each undeclared identifier is reported only once for each function it appears in
> >
> > commit 8a1ad4413519 ("tools headers: Remove now unused copies of
> > uapi/{fcntl,openat2}.h and asm/fcntl.h") removes fcntl.h from tools
> > headers directory, and fs_at_flags.c uses the 'AT_EACCESS' macro.
> > This macro was introduced in the kernel version v5.8.
> > For system with a kernel version older than this version,
> > it will cause compilation to fail.
>
> Thanks, I test on it, but since I didn't found libtraceevent-devel
> available there, then I have to build with NO_LIBTRACEEVENT=1 and thus
> this doesn't get built :-\
>
> Thanks, applying.

Yang also wrote:
https://lore.kernel.org/lkml/20240314063000.2139877-1-yangjihong@bytedance.com/
that may have helped you with this.

Thanks,
Ian

> - Arnaldo
>
> > Fixes: 8a1ad4413519 ("tools headers: Remove now unused copies of uapi/{fcntl,openat2}.h and asm/fcntl.h")
> > Signed-off-by: Yang Jihong <yangjihong@bytedance.com>
> > ---
> >  tools/perf/trace/beauty/fs_at_flags.c | 8 ++++++++
> >  1 file changed, 8 insertions(+)
> >
> > diff --git a/tools/perf/trace/beauty/fs_at_flags.c b/tools/perf/trace/beauty/fs_at_flags.c
> > index c1365e8f0b96..c200669cb944 100644
> > --- a/tools/perf/trace/beauty/fs_at_flags.c
> > +++ b/tools/perf/trace/beauty/fs_at_flags.c
> > @@ -10,6 +10,14 @@
> >  #include <linux/fcntl.h>
> >  #include <linux/log2.h>
> >
> > +/*
> > + * uapi/linux/fcntl.h does not keep a copy in tools headers directory,
> > + * for system with kernel versions before v5.8, need to sync AT_EACCESS macro.
> > + */
> > +#ifndef AT_EACCESS
> > +#define AT_EACCESS 0x200
> > +#endif
> > +
> >  #include "trace/beauty/generated/fs_at_flags_array.c"
> >  static DEFINE_STRARRAY(fs_at_flags, "AT_");
> >
> > --
> > 2.25.1
> >