Re: [PATCH 08/23] perf tools: Introduce perf data file version CHECK macro

[Jiri Olsa <jolsa@redhat.com>]

On Wed, Jul 17, 2013 at 04:42:50PM -0300, Arnaldo Carvalho de Melo wrote:
> Em Wed, Jul 17, 2013 at 07:49:48PM +0200, Jiri Olsa escreveu:
> > Introducing perf data file version CHECK macro, so the check
> > is easily extensible for new versions.
> > 
> > Signed-off-by: Jiri Olsa <jolsa@redhat.com>
> > Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
> > Cc: Frederic Weisbecker <fweisbec@gmail.com>
> > Cc: Ingo Molnar <mingo@elte.hu>
> > Cc: Namhyung Kim <namhyung@kernel.org>
> > Cc: Paul Mackerras <paulus@samba.org>
> > Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
> > Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
> > Cc: Andi Kleen <ak@linux.intel.com>
> > Cc: David Ahern <dsahern@gmail.com>
> > ---
> >  tools/perf/util/header.c | 27 ++++++++++++++++-----------
> >  1 file changed, 16 insertions(+), 11 deletions(-)
> > 
> > diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
> > index f558f83..4ebe4a1 100644
> > --- a/tools/perf/util/header.c
> > +++ b/tools/perf/util/header.c
> > @@ -2493,18 +2493,23 @@ static int check_magic_endian(u64 magic, uint64_t hdr_sz,
> >  	 * - encode endianness of file
> >  	 */
> >  
> > -	/* check magic number with one endianness */
> > -	if (magic == __perf_magic2)
> > -		return 0;
> > -
> > -	/* check magic number with opposite endianness */
> > -	if (magic != __perf_magic2_sw)
> > -		return -1;
> > +#define CHECK(__m, __v)						\
> > +do {								\
> > +	/* check magic number with one endianness */		\
> > +	if (magic == __m)					\
> > +		goto v ## __v;					\
> > +	/* check magic number with opposite endianness */	\
> > +	if (magic != __m ## _sw)				\
> > +		break;						\
> > +	ph->needs_swap = true;					\
> > + v ## __v:							\
> > +	ph->version = __v;					\
> > +	return 0;						\
> > +} while (0)
> 
> Ouch, why not:
> 
> #define PERF_CHECK_VERSION(__m, __v)
> 	/* check magic number with one endianness */		\
> 	if (magic == __m) {					\
> 		ph->version = __v;				\
> 		return 0;					\
> 	/* check magic number with opposite endianness */	\
> 	} else if (magic == __m ## _sw) {			\
> 		ph->needs_swap = true;				\
> 	}

ok, will change

thanks,
jirka