Re: [PATCH] tracing: remove unused ret

[Alex Shi <alex.shi@linux.alibaba.com>]

在 2020/1/22 上午6:35, Steven Rostedt 写道:
> On Tue, 21 Jan 2020 13:54:43 +0800
> Alex Shi <alex.shi@linux.alibaba.com> wrote:
> 
>> No body care the variable 'ret' in function unregister_field_var_hists,
>> better to remove it.
>>
>> Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
>> Cc: Steven Rostedt <rostedt@goodmis.org> 
>> Cc: Ingo Molnar <mingo@redhat.com> 
>> Cc: linux-kernel@vger.kernel.org 
>> ---
>>  kernel/trace/trace_events_hist.c | 3 +--
>>  1 file changed, 1 insertion(+), 2 deletions(-)
>>
>> diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
>> index f62de5f43e79..0acfac95ca2a 100644
>> --- a/kernel/trace/trace_events_hist.c
>> +++ b/kernel/trace/trace_events_hist.c
>> @@ -5712,12 +5712,11 @@ static void unregister_field_var_hists(struct hist_trigger_data *hist_data)
>>  	struct trace_event_file *file;
>>  	unsigned int i;
>>  	char *cmd;
>> -	int ret;
>>  
>>  	for (i = 0; i < hist_data->n_field_var_hists; i++) {
>>  		file = hist_data->field_var_hists[i]->hist_data->event_file;
>>  		cmd = hist_data->field_var_hists[i]->cmd;
>> -		ret = event_hist_trigger_func(&trigger_hist_cmd, file,
>> +		event_hist_trigger_func(&trigger_hist_cmd, file,
> 
> I pulled in some of your other patches (removing unused macros), but
> these that remove 'ret' I prefer not to take. Yes, we currently do not
> use ret here, but the compiler will easily remove its existence. I'm
> thinking if anything, we should report an error if they do return
> something other than success.
> 
> -- Steve
> 

Pretty make sense. :)

Thanks!
Alex