Re: [PATCH V2 4/6] perf tools: Add FIFO file names as alternative options to --control

[Jiri Olsa <jolsa@redhat.com>]

On Tue, Sep 01, 2020 at 12:37:56PM +0300, Adrian Hunter wrote:

SNIP

> +	fd = open(s, O_RDWR | O_NONBLOCK | O_CLOEXEC);
> +	if (fd < 0) {
> +		pr_err("Failed to open '%s'\n", s);
> +		ret = -errno;
> +		goto out_free;
> +	}
> +	*ctl_fd = fd;
> +	*ctl_fd_close = true;
> +
> +	if (p && *++p) {
> +		/* O_RDWR | O_NONBLOCK means the other end need not be open */
> +		fd = open(p, O_RDWR | O_NONBLOCK | O_CLOEXEC);
> +		if (fd < 0) {
> +			pr_err("Failed to open '%s'\n", p);
> +			ret = -errno;
> +			goto out_free;
> +		}
> +		*ctl_fd_ack = fd;
> +	}
> +
> +out_free:
> +	free(s);
> +	return ret;
> +}
> +
> +int evlist__parse_control(const char *str, int *ctl_fd, int *ctl_fd_ack, bool *ctl_fd_close)
>  {
>  	char *comma = NULL, *endptr = NULL;
>  
>  	if (strncmp(str, "fd:", 3))
> -		return -EINVAL;
> +		return evlist__parse_control_names(str, ctl_fd, ctl_fd_ack, ctl_fd_close);

could you please proactively set *ctl_fd_close = false in here,
so it's obvious.. also evlist__parse_control_fifo might be better
name, other that that it all looks great

we were recently asked to prvide faster intel_pt snapshot control
and we were thinking of putting input_pt support to libperf, but
your change might just fix this

for the patchset:

Acked-by: Jiri Olsa <jolsa@redhat.com>

Alexey, could you please check on this?

thanks,
jirka

>  
>  	*ctl_fd = strtoul(&str[3], &endptr, 0);
>  	if (endptr == &str[3])

SNIP