On Tue, Oct 22, 2019 at 05:53:33PM -0700, Ian Rogers wrote:
> Use realloc rather than malloc+memcpy to possibly avoid a memory
> allocation when appending array elements.
> 
> Signed-off-by: Ian Rogers <irog...@google.com>

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

thanks,
jirka

> ---
>  tools/perf/util/parse-events.y | 8 +++-----
>  1 file changed, 3 insertions(+), 5 deletions(-)
> 
> diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y
> index 26cb65798522..545ab7cefc20 100644
> --- a/tools/perf/util/parse-events.y
> +++ b/tools/perf/util/parse-events.y
> @@ -691,14 +691,12 @@ array_terms ',' array_term
>       struct parse_events_array new_array;
>  
>       new_array.nr_ranges = $1.nr_ranges + $3.nr_ranges;
> -     new_array.ranges = malloc(sizeof(new_array.ranges[0]) *
> -                               new_array.nr_ranges);
> +     new_array.ranges = realloc($1.ranges,
> +                             sizeof(new_array.ranges[0]) *
> +                             new_array.nr_ranges);
>       ABORT_ON(!new_array.ranges);
> -     memcpy(&new_array.ranges[0], $1.ranges,
> -            $1.nr_ranges * sizeof(new_array.ranges[0]));
>       memcpy(&new_array.ranges[$1.nr_ranges], $3.ranges,
>              $3.nr_ranges * sizeof(new_array.ranges[0]));
> -     free($1.ranges);
>       free($3.ranges);
>       $$ = new_array;
>  }
> -- 
> 2.23.0.866.gb869b98d4c-goog
> 

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