Re: [PATCH V2 1/8] perf tools: remove stale perf evlist mmap read for backward

[Wangnan (F)]

On 2017/12/7 7:32, kan.liang@xxxxxxxxx wrote:
> From: Kan Liang <kan.liang@xxxxxxxxx>
>
> perf_evlist__mmap_read_catchup and perf_evlist__mmap_read_backward are
> only for overwrite mode.
> But they read the evlist->mmap buffer which is for non-overwrite mode.
>
> It did not bring any serious problem yet, because there is no one use
> it.
>
> Remove the unused interfaces.
>
> Signed-off-by: Kan Liang <kan.liang@xxxxxxxxx>

Acked-by: Wang Nan <wangnan0@xxxxxxxxxx>

> ---
>   tools/perf/util/evlist.c | 17 -----------------
>   tools/perf/util/evlist.h |  4 ----
>   2 files changed, 21 deletions(-)
>
> diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
> index 3570355..4b6a06d 100644
> --- a/tools/perf/util/evlist.c
> +++ b/tools/perf/util/evlist.c
> @@ -714,28 +714,11 @@ union perf_event *perf_evlist__mmap_read_forward(struct perf_evlist *evlist, int
>   	return perf_mmap__read_forward(md);
>   }
>   
> -union perf_event *perf_evlist__mmap_read_backward(struct perf_evlist *evlist, int idx)
> -{
> -	struct perf_mmap *md = &evlist->mmap[idx];
> -
> -	/*
> -	 * No need to check messup for backward ring buffer:
> -	 * We can always read arbitrary long data from a backward
> -	 * ring buffer unless we forget to pause it before reading.
> -	 */
> -	return perf_mmap__read_backward(md);
> -}
> -
>   union perf_event *perf_evlist__mmap_read(struct perf_evlist *evlist, int idx)
>   {
>   	return perf_evlist__mmap_read_forward(evlist, idx);
>   }
>   
> -void perf_evlist__mmap_read_catchup(struct perf_evlist *evlist, int idx)
> -{
> -	perf_mmap__read_catchup(&evlist->mmap[idx]);
> -}
> -
>   void perf_evlist__mmap_consume(struct perf_evlist *evlist, int idx)
>   {
>   	perf_mmap__consume(&evlist->mmap[idx], false);
> diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h
> index 7516066..a80fd47 100644
> --- a/tools/perf/util/evlist.h
> +++ b/tools/perf/util/evlist.h
> @@ -132,10 +132,6 @@ union perf_event *perf_evlist__mmap_read(struct perf_evlist *evlist, int idx);
>   
>   union perf_event *perf_evlist__mmap_read_forward(struct perf_evlist *evlist,
>   						 int idx);
> -union perf_event *perf_evlist__mmap_read_backward(struct perf_evlist *evlist,
> -						  int idx);
> -void perf_evlist__mmap_read_catchup(struct perf_evlist *evlist, int idx);
> -
>   void perf_evlist__mmap_consume(struct perf_evlist *evlist, int idx);
>   
>   int perf_evlist__open(struct perf_evlist *evlist);