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Date:   Fri, 22 Jan 2021 16:00:52 -0500
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Tom Zanussi <zanussi@kernel.org>
Cc:     axelrasmussen@google.com, mhiramat@kernel.org,
        dan.carpenter@oracle.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v6 2/6] tracing: Rework synthetic event command parsing
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References: <cover.1611243025.git.zanussi@kernel.org>
        <f3c2d2841307de0a7624a250f8f9653d435602c9.1611243025.git.zanussi@kernel.org>
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On Thu, 21 Jan 2021 11:01:05 -0600
Tom Zanussi <zanussi@kernel.org> wrote:

> @@ -1208,13 +1173,14 @@ static int __create_synth_event(int argc, const char *name, const char **argv)
>  	 *      where 'field' = type field_name
>  	 */
>  
> -	if (name[0] == '\0' || argc < 1) {
> +	mutex_lock(&event_mutex);

I'm curious, why is the event_mutex taken here? I'm guessing it is first
needed for the find_synth_event() call, in which case, it can be moved
after the is_good_name() check. I don't see why the goto out is required
here or for the is_good_name() check.

-- Steve

> +
> +	if (name[0] == '\0') {
>  		synth_err(SYNTH_ERR_CMD_INCOMPLETE, 0);
> -		return -EINVAL;
> +		ret = -EINVAL;
> +		goto out;
>  	}
>  
> -	mutex_lock(&event_mutex);
> -
>  	if (!is_good_name(name)) {
>  		synth_err(SYNTH_ERR_BAD_NAME, errpos(name));
>  		ret = -EINVAL;