Re: [PATCH 06/21] perf hists: Return error from hists__collapse_resort()

[Arnaldo Carvalho de Melo]

Em Tue, Feb 02, 2016 at 11:39:48PM +0900, Namhyung Kim escreveu:
> Currently hists__collapse_resort() and hists__collapse_insert_entry()
> don't return error code. Now callchain_merge() can check error case,
> abort and pass the error to the user.  Later patch can add more work
> which can be failed too.
> 
> Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>
> Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
> ---
>  tools/perf/util/hist.c | 27 +++++++++++++++++----------
>  tools/perf/util/hist.h |  4 ++--
>  2 files changed, 19 insertions(+), 12 deletions(-)
> 
> diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
> index 098310bc4489..b476b599e415 100644
> --- a/tools/perf/util/hist.c
> +++ b/tools/perf/util/hist.c
> @@ -1016,8 +1016,8 @@ void hist_entry__delete(struct hist_entry *he)
>   * collapse the histogram
>   */
>  
> -bool hists__collapse_insert_entry(struct hists *hists __maybe_unused,
> -				  struct rb_root *root, struct hist_entry *he)
> +int hists__collapse_insert_entry(struct hists *hists, struct rb_root *root,
> +				 struct hist_entry *he)
>  {
>  	struct rb_node **p = &root->rb_node;
>  	struct rb_node *parent = NULL;
> @@ -1037,12 +1037,13 @@ bool hists__collapse_insert_entry(struct hists *hists __maybe_unused,
>  
>  			if (symbol_conf.use_callchain) {
>  				callchain_cursor_reset(&callchain_cursor);
> -				callchain_merge(&callchain_cursor,
> -						iter->callchain,
> -						he->callchain);
> +				if (callchain_merge(&callchain_cursor,
> +						    iter->callchain,
> +						    he->callchain) < 0)
> +					return -1;

So now we're exiting on error here, whereas before we would
unconditionally call hist_entry__delete() right after this branch... Is
that right?

Looking at it...

>  			}
>  			hist_entry__delete(he);
> -			return false;
> +			return 0;
>  		}
>  
>  		if (cmp < 0)
> @@ -1054,7 +1055,7 @@ bool hists__collapse_insert_entry(struct hists *hists __maybe_unused,
>  
>  	rb_link_node(&he->rb_node_in, parent, p);
>  	rb_insert_color(&he->rb_node_in, root);
> -	return true;
> +	return 1;
>  }
>  
>  struct rb_root *hists__get_rotate_entries_in(struct hists *hists)
> @@ -1080,14 +1081,15 @@ static void hists__apply_filters(struct hists *hists, struct hist_entry *he)
>  	hists__filter_entry_by_socket(hists, he);
>  }
>  
> -void hists__collapse_resort(struct hists *hists, struct ui_progress *prog)
> +int hists__collapse_resort(struct hists *hists, struct ui_progress *prog)
>  {
>  	struct rb_root *root;
>  	struct rb_node *next;
>  	struct hist_entry *n;
> +	int ret;
>  
>  	if (!sort__need_collapse)
> -		return;
> +		return 0;
>  
>  	hists->nr_entries = 0;
>  
> @@ -1102,7 +1104,11 @@ void hists__collapse_resort(struct hists *hists, struct ui_progress *prog)
>  		next = rb_next(&n->rb_node_in);
>  
>  		rb_erase(&n->rb_node_in, root);
> -		if (hists__collapse_insert_entry(hists, &hists->entries_collapsed, n)) {
> +		ret = hists__collapse_insert_entry(hists, &hists->entries_collapsed, n);
> +		if (ret < 0)
> +			return -1;
> +
> +		if (ret) {
>  			/*
>  			 * If it wasn't combined with one of the entries already
>  			 * collapsed, we need to apply the filters that may have
> @@ -1113,6 +1119,7 @@ void hists__collapse_resort(struct hists *hists, struct ui_progress *prog)
>  		if (prog)
>  			ui_progress__update(prog, 1);
>  	}
> +	return 0;
>  }
>  
>  static int hist_entry__sort(struct hist_entry *a, struct hist_entry *b)
> diff --git a/tools/perf/util/hist.h b/tools/perf/util/hist.h
> index d4ec4822a103..9c72f8331d1c 100644
> --- a/tools/perf/util/hist.h
> +++ b/tools/perf/util/hist.h
> @@ -129,7 +129,7 @@ int hist_entry__sort_snprintf(struct hist_entry *he, char *bf, size_t size,
>  void hist_entry__delete(struct hist_entry *he);
>  
>  void hists__output_resort(struct hists *hists, struct ui_progress *prog);
> -void hists__collapse_resort(struct hists *hists, struct ui_progress *prog);
> +int hists__collapse_resort(struct hists *hists, struct ui_progress *prog);
>  
>  void hists__decay_entries(struct hists *hists, bool zap_user, bool zap_kernel);
>  void hists__delete_entries(struct hists *hists);
> @@ -188,7 +188,7 @@ int hists__init(void);
>  int __hists__init(struct hists *hists);
>  
>  struct rb_root *hists__get_rotate_entries_in(struct hists *hists);
> -bool hists__collapse_insert_entry(struct hists *hists __maybe_unused,
> +int hists__collapse_insert_entry(struct hists *hists,
>  				  struct rb_root *root, struct hist_entry *he);
>  
>  struct perf_hpp {
> -- 
> 2.6.4