Re: [PATCH v2] perf tools: use PTR_ERR_OR_ZERO inetead of return code

[Arnaldo Carvalho de Melo]

Em Thu, Sep 06, 2018 at 07:42:51PM +0800, Ding Xiang escreveu:
> use PTR_ERR_OR_ZERO for bpf__setup_stdout return code
> 
> v2: add macro PTR_ERR_OR_ZERO to err.h

This really should be done in two patches, one introducing the
PTR_ERR_OR_ZERO() macro, and then the use of it in bpf-loader.c.

Thanks,

- Arnaldo
 
> Signed-off-by: Ding Xiang <dingxiang@xxxxxxxxxxxxxxxxxxxx>
> ---
>  tools/include/linux/err.h    | 7 +++++++
>  tools/perf/util/bpf-loader.c | 2 +-
>  2 files changed, 8 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/include/linux/err.h b/tools/include/linux/err.h
> index 7a8b61a..0946496 100644
> --- a/tools/include/linux/err.h
> +++ b/tools/include/linux/err.h
> @@ -52,4 +52,11 @@ static inline bool __must_check IS_ERR_OR_NULL(__force const void *ptr)
>  	return unlikely(!ptr) || IS_ERR_VALUE((unsigned long)ptr);
>  }
>  
> +static inline int __must_check PTR_ERR_OR_ZERO(__force const void *ptr)
> +{
> +	if (IS_ERR(ptr))
> +		return PTR_ERR(ptr);
> +	else
> +		return 0;
> +}
>  #endif /* _LINUX_ERR_H */
> diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c
> index 47aac41..f9ae1a9 100644
> --- a/tools/perf/util/bpf-loader.c
> +++ b/tools/perf/util/bpf-loader.c
> @@ -1615,7 +1615,7 @@ struct perf_evsel *bpf__setup_output_event(struct perf_evlist *evlist, const cha
>  int bpf__setup_stdout(struct perf_evlist *evlist)
>  {
>  	struct perf_evsel *evsel = bpf__setup_output_event(evlist, "__bpf_stdout__");
> -	return IS_ERR(evsel) ? PTR_ERR(evsel) : 0;
> +	return PTR_ERR_OR_ZERO(evsel);
>  }
>  
>  #define ERRNO_OFFSET(e)		((e) - __BPF_LOADER_ERRNO__START)
> -- 
> 1.9.1
> 
>