Re: [PATCH] perf tool: Fix cross-endian analysis

[Jiri Olsa <jolsa@redhat.com>]

On Thu, Apr 09, 2015 at 04:15:46PM -0400, David Ahern wrote:
> Trying to analyze a big endian data file on little endian system
> fails with the error:
>   0xa9b40 [0x70]: failed to process type: 9
> 
> The problem is that header parsing is not done correctly because
> the file attributes are not swapped. Make it so. With this patch
> able to analyze a sparc64 data file on x86_64.
> 
> Signed-off-by: David Ahern <david.ahern@oracle.com>
> Cc: Jiri Olsa <jolsa@kernel.org>
> Cc: Namhyung Kim <namhyung@kernel.org>
> ---
>  tools/perf/util/header.c |    5 ++++-
>  1 files changed, 4 insertions(+), 1 deletions(-)
> 
> diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
> index e38cf62..45b7e72 100644
> --- a/tools/perf/util/header.c
> +++ b/tools/perf/util/header.c
> @@ -2586,8 +2586,11 @@ int perf_session__read_header(struct perf_session *session)
>  		if (read_attr(fd, header, &f_attr) < 0)
>  			goto out_errno;
>  
> -		if (header->needs_swap)
> +		if (header->needs_swap) {
> +			f_attr.ids.size   = bswap_64(f_attr.ids.size);
> +			f_attr.ids.offset = bswap_64(f_attr.ids.offset);
>  			perf_event__attr_swap(&f_attr.attr);
> +		}

so people do actually use it ;-)

Acked-by: Jiri Olsa <jolsa@kernel.org>

thanks,
jirka