Re: [PATCH] perf stat: Use nftw() instead of ftw()

[Arnaldo Carvalho de Melo]

Em Mon, Feb 08, 2021 at 06:11:57PM +0000, Paul Cercueil escreveu:
> ftw() has been obsolete for about 12 years now.
> 
> Fixes: bb1c15b60b98 ("perf stat: Support regex pattern in --for-each-cgroup")
> CC: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
> ---
> 
> Notes:
>     NOTE: Not runtime-tested, I have no idea what I need to do in perf
>     to test this. But at least it compiles now with my uClibc-based
>     toolchain.

Seems safe from reading the nftw() man page, the only typeflag that this
code is using is FTW_D and that is present in both ftw() and nftw().

Applying,

- Arnaldo
 
>  tools/perf/util/cgroup.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/tools/perf/util/cgroup.c b/tools/perf/util/cgroup.c
> index 5dff7e489921..f24ab4585553 100644
> --- a/tools/perf/util/cgroup.c
> +++ b/tools/perf/util/cgroup.c
> @@ -161,7 +161,7 @@ void evlist__set_default_cgroup(struct evlist *evlist, struct cgroup *cgroup)
>  
>  /* helper function for ftw() in match_cgroups and list_cgroups */
>  static int add_cgroup_name(const char *fpath, const struct stat *sb __maybe_unused,
> -			   int typeflag)
> +			   int typeflag, struct FTW *ftwbuf __maybe_unused)
>  {
>  	struct cgroup_name *cn;
>  
> @@ -209,12 +209,12 @@ static int list_cgroups(const char *str)
>  			if (!s)
>  				return -1;
>  			/* pretend if it's added by ftw() */
> -			ret = add_cgroup_name(s, NULL, FTW_D);
> +			ret = add_cgroup_name(s, NULL, FTW_D, NULL);
>  			free(s);
>  			if (ret)
>  				return -1;
>  		} else {
> -			if (add_cgroup_name("", NULL, FTW_D) < 0)
> +			if (add_cgroup_name("", NULL, FTW_D, NULL) < 0)
>  				return -1;
>  		}
>  
> @@ -247,7 +247,7 @@ static int match_cgroups(const char *str)
>  	prefix_len = strlen(mnt);
>  
>  	/* collect all cgroups in the cgroup_list */
> -	if (ftw(mnt, add_cgroup_name, 20) < 0)
> +	if (nftw(mnt, add_cgroup_name, 20, 0) < 0)
>  		return -1;
>  
>  	for (;;) {
> -- 
> 2.30.0
> 

-- 

- Arnal