Re: [PATCH v6 2/7] perf util: Get the evsel_streams by evsel_idx

[Arnaldo Carvalho de Melo <acme@kernel.org>]

Em Fri, Sep 11, 2020 at 04:03:48PM +0800, Jin Yao escreveu:
> In previous patch, we have created evsel_streams array
> 
> This patch returns the specified evsel_streams according to the
> evsel_idx.
> 
> Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
> ---
>  v6:
>    - Rebase to perf/core
> 
>  v5:
>    - Rebase to perf/core
> 
>  v4:
>    - Rename the patch from 'perf util: Return per-event callchain
>      streams' to 'perf util: Get the evsel_streams by evsel_idx'
> 
>  tools/perf/util/stream.c | 11 +++++++++++
>  tools/perf/util/stream.h |  3 +++
>  2 files changed, 14 insertions(+)
> 
> diff --git a/tools/perf/util/stream.c b/tools/perf/util/stream.c
> index 015c1d07ce3a..7882a7f05d97 100644
> --- a/tools/perf/util/stream.c
> +++ b/tools/perf/util/stream.c
> @@ -146,3 +146,14 @@ struct evsel_streams *perf_evlist__create_streams(struct evlist *evlist,
>  
>  	return es;
>  }
> +
> +struct evsel_streams *evsel_streams_get(struct evsel_streams *es,
> +					int nr_evsel, int evsel_idx)

  foo__get() is the idiom for refcount_t method to bump the refcount for
  'struct foo', so please rename it to:

  struct evsel_streams__entry(struct evsel_streams *es, int nr_evsel, int evsel_idx)

Also please consider having the array and the number of entries in
'struct evsel_streams', so that you don't have to always pass the
number of entries around.

> +{
> +	for (int i = 0; i < nr_evsel; i++) {
> +		if (es[i].evsel_idx == evsel_idx)
> +			return &es[i];
> +	}
> +
> +	return NULL;
> +}
> diff --git a/tools/perf/util/stream.h b/tools/perf/util/stream.h
> index c6844c5787cb..66f61d954eef 100644
> --- a/tools/perf/util/stream.h
> +++ b/tools/perf/util/stream.h
> @@ -20,4 +20,7 @@ struct evlist;
>  struct evsel_streams *perf_evlist__create_streams(struct evlist *evlist,
>  						  int nr_streams_max);
>  
> +struct evsel_streams *evsel_streams_get(struct evsel_streams *es,
> +					int nr_evsel, int evsel_idx);
> +
>  #endif /* __PERF_STREAM_H */
> -- 
> 2.17.1
> 

-- 

- Arnaldo