Re: [PATCH] rcu: Reword help of RCU_TRACE option

[Nikolay Borisov]

On 10/05/2016 05:03 PM, Paul E. McKenney wrote:
> On Wed, Oct 05, 2016 at 10:06:21AM +0300, Nikolay Borisov wrote:
>> Explicitly state that enabling RCU_TRACE enables more
>> tracepoints and not just "additional tracing".
>>
>> Signed-off-by: Nikolay Borisov <kernel@xxxxxxxx>
>> ---
>>
>> Hello Paul, 
>>
>> Following our latest conversation re. enabling RCU tracing
>> I had to actually go and look into the code to see which 
>> option enables the additional tracepoints. I wasn't sure
>> while reading the help of TRACE_RCU. So here is a patch
>> which explicitly states that this enables additional 
>> tracepoints. 
>>
>> Apply it if you deem necessary it might be just me that 
>> thinks the description is not verbose enough. 
>>
>>  lib/Kconfig.debug | 4 ++--
>>  1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
>> index cab7405f48d2..f8c3468ec7ef 100644
>> --- a/lib/Kconfig.debug
>> +++ b/lib/Kconfig.debug
>> @@ -1429,8 +1429,8 @@ config RCU_TRACE
>>  	depends on DEBUG_KERNEL
>>  	select TRACE_CLOCK
>>  	help
>> -	  This option provides tracing in RCU which presents stats
>> -	  in debugfs for debugging RCU implementation.
>> +	  This option enables additional tracepoints in RCU which present
>> +	  stats in debugfs for debugging RCU implementation.
> 
> How about something like this?
> 
> 	This option provides tracing in RCU which presents stats
> 	in debugfs for debugging RCU implementation.  It also enables
> 	additional tracepoints for ftrace-style event tracing.

So long as it's explicitly stated that it also enables tracepoints it's
all fine by me. Apparently I'm not the only one who got confused. In a
question re. CONFIG_RCU_TRACE here is what someone said on IRC:

"what's tracepoints do you mean? this option enables the additional
statistics permanently."

Care to apply it with the revised wording or shall I resend?

> 
> 							Thanx, Paul
> 
>>
>>  	  Say Y here if you want to enable RCU tracing
>>  	  Say N if you are unsure.
>> -- 
>> 2.5.0
>>
>