Re: [PATCH v4 2/3] perf/sdt : Support perf-list to print SDT events in a single file

[Masami Hiramatsu <masami dot hiramatsu dot pt at hitachi dot com>]

(2014/08/28 6:50), Hemant Kumar wrote:
[...]
> +/*
> + * get_sdt_note_info(): flush the SDT notes onto stdout
> + */
> +static void get_sdt_note_info(struct list_head *start, const char *target)
> +{
> +	struct sdt_note *pos;
> +
> +	if (list_empty(start))
> +		return;
> +
> +	printf("%s :\n", target);
> +	list_for_each_entry(pos, start, note_list) {
> +		printf("%%%s : %s\n", pos->provider, pos->name);

Hmm, this will show

 %app : marker

instead of

 %app:marker

(blanks are placed around ":")
I think it should be the latter format.

> +	}
> +}
> +
> +/*
> + * Error displayed in case of query of a
> + * single file for SDT markers
> + */
> +static int sdt_err(int val, const char *target)
> +{
> +	switch (-val) {
> +	case 0:
> +		break;
> +	case ENOENT:
> +		/* Absence of SDT markers */
> +		printf("%s : No SDT events found\n", target);

Please use pr_err or pr_warning for error messages.

> +		break;
> +	case EBADF:
> +		printf("%s : Bad file name\n", target);
> +		break;
> +	default:
> +		printf("%s\n", strerror(val));
> +	}

And strerror_r instead of strerror (see https://lkml.org/lkml/2014/8/13/828)

> +
> +	return val;
> +}
> +
> +/*
> + * cleanup_sdt_note_list() : Free the sdt note list
> + */
> +static void cleanup_sdt_note_list(struct list_head *sdt_notes)
> +{
> +	struct sdt_note *tmp, *pos;
> +
> +	if (list_empty(sdt_notes))
> +		return;

You don't need to check this. If the list is empty list_for_each...
just skips loops.

> +
> +	list_for_each_entry_safe(pos, tmp, sdt_notes, note_list) {
> +		list_del(&pos->note_list);
> +		free(pos->name);
> +		free(pos->provider);
> +		free(pos);
> +	}
> +}

Thank you,

> +
> +/*
> + * filename__find_sdt() : looks for sdt markers and the list is
> + * stored in sdt_notes
> + */
> +static int filename__find_sdt(const char *target)
> +{
> +	int ret;
> +
> +	LIST_HEAD(sdt_notes);
> +
> +	ret = get_sdt_note_list(&sdt_notes, target);
> +	if (!ret)
> +		get_sdt_note_info(&sdt_notes, target);
> +	else
> +		sdt_err(ret, target);
> +
> +	cleanup_sdt_note_list(&sdt_notes);
> +
> +	return ret;
> +}
> +
> +/*
> + * print_sdt_notes() : wrapper function
> + */
> +void print_sdt_events(const char *arg)
> +{
> +	if (arg) {
> +		filename__find_sdt(arg);
> +		return;
> +	}
> +	pr_err("Error : File Name must be specified with \"sdt\" option!\n"
> +	       "Usage :\n  perf list sdt <file-name>\n");
> +
> +	return;
> +}
> 
> 


-- 
Masami HIRAMATSU
Software Platform Research Dept. Linux Technology Research Center
Hitachi, Ltd., Yokohama Research Laboratory
E-mail: masami.hiramatsu.pt@hitachi.com