Re: [PATCH RFC 1/7] perf jevents: Add support for an extra directory level

[Jiri Olsa]

On Fri, Jan 24, 2020 at 10:34:59PM +0800, John Garry wrote:
> Currently we support upto a level 2 directory, and level 2 would be in the
> form vendor/platform.
> 
> Add support for a further level, to hold specific categories of events for
> when we want to segregate them for matching purposes.
> 
> Signed-off-by: John Garry <john.garry@xxxxxxxxxx>
> ---
>  tools/perf/pmu-events/jevents.c | 11 ++++++++---
>  1 file changed, 8 insertions(+), 3 deletions(-)
> 
> diff --git a/tools/perf/pmu-events/jevents.c b/tools/perf/pmu-events/jevents.c
> index 079c77b6a2fd..8af05b94a37d 100644
> --- a/tools/perf/pmu-events/jevents.c
> +++ b/tools/perf/pmu-events/jevents.c
> @@ -960,15 +960,20 @@ static int process_one_file(const char *fpath, const struct stat *sb,
>  	int level   = ftwbuf->level;
>  	int err = 0;
>  
> -	if (level == 2 && is_dir) {
> +	if (level >= 2 && is_dir) {
> +		int count = 0;
>  		/*
>  		 * For level 2 directory, bname will include parent name,
>  		 * like vendor/platform. So search back from platform dir
>  		 * to find this.
> +		 * Something similar for level 3 directory, but we're a PMU
> +		 * category folder, like vendor/platform/cpu.
>  		 */
>  		bname = (char *) fpath + ftwbuf->base - 2;
>  		for (;;) {
>  			if (*bname == '/')
> +				count++;
> +			if (count == level - 1)
>  				break;
>  			bname--;

I was wondering why we just don't use different filename for that,
but it's true that the code transforms directory chain to the table
name.. so I guess another directory level is justified ;-)

jirka


>  		}
> @@ -981,13 +986,13 @@ static int process_one_file(const char *fpath, const struct stat *sb,
>  		 level, sb->st_size, bname, fpath);
>  
>  	/* base dir or too deep */
> -	if (level == 0 || level > 3)
> +	if (level == 0 || level > 4)
>  		return 0;
>  
>  
>  	/* model directory, reset topic */
>  	if ((level == 1 && is_dir && is_leaf_dir(fpath)) ||
> -	    (level == 2 && is_dir)) {
> +	    (level >= 2 && is_dir && is_leaf_dir(fpath))) {
>  		if (close_table)
>  			print_events_table_suffix(eventsfp);
>  
> -- 
> 2.17.1
>