Re: [PATCH 1/4] perf cgroup: Avoid needless closing of unopened fd

From: Jiri Olsa
Date: Mon Apr 20 2020 - 04:49:27 EST


On Fri, Apr 17, 2020 at 04:23:26PM +0300, Tommi Rantala wrote:
> Do not bother with close() if fd is not valid, just to silence valgrind:
>
> $ valgrind ./perf script
> ==59169== Memcheck, a memory error detector
> ==59169== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
> ==59169== Using Valgrind-3.14.0 and LibVEX; rerun with -h for copyright info
> ==59169== Command: ./perf script
> ==59169==
> ==59169== Warning: invalid file descriptor -1 in syscall close()
> ==59169== Warning: invalid file descriptor -1 in syscall close()
> ==59169== Warning: invalid file descriptor -1 in syscall close()
> ==59169== Warning: invalid file descriptor -1 in syscall close()
> ==59169== Warning: invalid file descriptor -1 in syscall close()
> ==59169== Warning: invalid file descriptor -1 in syscall close()
> ==59169== Warning: invalid file descriptor -1 in syscall close()
> ==59169== Warning: invalid file descriptor -1 in syscall close()
>
> Signed-off-by: Tommi Rantala <tommi.t.rantala@xxxxxxxxx>

Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>

thanks,
jirka

> ---
> tools/perf/util/cgroup.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/tools/perf/util/cgroup.c b/tools/perf/util/cgroup.c
> index b73fb7823048..050dea9f1e88 100644
> --- a/tools/perf/util/cgroup.c
> +++ b/tools/perf/util/cgroup.c
> @@ -107,7 +107,8 @@ static int add_cgroup(struct evlist *evlist, const char *str)
>
> static void cgroup__delete(struct cgroup *cgroup)
> {
> - close(cgroup->fd);
> + if (cgroup->fd >= 0)
> + close(cgroup->fd);
> zfree(&cgroup->name);
> free(cgroup);
> }
> --
> 2.25.2
>