Re: [PATCH 1/5] ftrace: remove redundant strsep in mod_callback

[Steven Rostedt <rostedt@goodmis.org>]

On Tue, 29 Sep 2015 19:46:12 +0300
Dmitry Safonov <0x7f454c46@gmail.com> wrote:

> By now there isn't any subcommand for mod.
> 
> Before:
> 	sh$ echo '*:mod:ipv6:a' > set_ftrace_filter
> 	sh$ echo '*:mod:ipv6' > set_ftrace_filter
> had the same results, but now first will result in:
> 	sh$ echo '*:mod:ipv6:a' > set_ftrace_filter
> 	-bash: echo: write error: Invalid argument
> 
> Also, I clarified ftrace_mod_callback code a little.

Thanks for the patches. I don't have time to look at them at the moment
as I'm trying to finish up some stuff before I leave for LinuxCon EU.

If you don't hear from me by Monday, feel free to ping me again. I'll
be in Dublin (for LinuxCon), but I should be able to take a look at the
patches while I'm there. What do you think keynotes are for ;-)

-- Steve

> 
> Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com>
> ---
>  kernel/trace/ftrace.c | 17 ++++++-----------
>  1 file changed, 6 insertions(+), 11 deletions(-)
> 
> diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
> index b0623ac..f87401b 100644
> --- a/kernel/trace/ftrace.c
> +++ b/kernel/trace/ftrace.c
> @@ -3564,8 +3564,7 @@ static int
>  ftrace_mod_callback(struct ftrace_hash *hash,
>  		    char *func, char *cmd, char *param, int enable)
>  {
> -	char *mod;
> -	int ret = -EINVAL;
> +	int ret;
>  
>  	/*
>  	 * cmd == 'mod' because we only registered this func
> @@ -3576,16 +3575,12 @@ ftrace_mod_callback(struct ftrace_hash *hash,
>  	 */
>  
>  	/* we must have a module name */
> -	if (!param)
> -		return ret;
> -
> -	mod = strsep(&param, ":");
> -	if (!strlen(mod))
> -		return ret;
> +	if (!param || !strlen(param))
> +		return -EINVAL;
>  
> -	ret = ftrace_match_module_records(hash, func, mod);
> -	if (!ret)
> -		ret = -EINVAL;
> +	ret = ftrace_match_module_records(hash, func, param);
> +	if (ret == 0)
> +		return -EINVAL;
>  	if (ret < 0)
>  		return ret;
>