Re: [PATCH 1/2] tracing: Fix function graph duration format for 7-digit number

[Jungseok Lee <jungseoklee85@gmail.com>]

On Jul 17, 2015, at 10:44 AM, Steven Rostedt wrote:

Hi, Steve

Thanks for caring about this!

> On Sat, 11 Jul 2015 14:51:39 +0000
> Jungseok Lee <jungseoklee85@gmail.com> wrote:
> 
>> diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
>> index 8968bf7..0bc16c4 100644
>> --- a/kernel/trace/trace_functions_graph.c
>> +++ b/kernel/trace/trace_functions_graph.c
>> @@ -716,6 +716,8 @@ trace_print_graph_duration(unsigned long long duration, struct trace_seq *s)
>> 		snprintf(nsecs_str, slen, "%03lu", nsecs_rem);
>> 		trace_seq_printf(s, ".%s", nsecs_str);
>> 		len += strlen(nsecs_str);
>> +	} else if (len == 7) {
>> +		len -= 1;
> 
> Don't you mean len--;

You're right.

>> 	}
>> 
>> 	trace_seq_puts(s, " us ");
> 
> I don't care much for an extra branch here. I'm going to go with the
> following patch:
> 
> -- Steve
> 
> diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
> index 8968bf720c12..ca98445782ac 100644
> --- a/kernel/trace/trace_functions_graph.c
> +++ b/kernel/trace/trace_functions_graph.c
> @@ -715,13 +715,13 @@ trace_print_graph_duration(unsigned long long duration, struct trace_seq *s)
> 
> 		snprintf(nsecs_str, slen, "%03lu", nsecs_rem);
> 		trace_seq_printf(s, ".%s", nsecs_str);
> -		len += strlen(nsecs_str);
> +		len += strlen(nsecs_str) + 1;
> 	}
> 
> 	trace_seq_puts(s, " us ");
> 
> 	/* Print remaining spaces to fit the row's width */
> -	for (i = len; i < 7; i++)
> +	for (i = len; i < 8; i++)
> 		trace_seq_putc(s, ' ');
> }

This change is better than my approach. As expected, it works well.

Best Regards
Jungseok Lee