On 10/06/2016 03:45 PM, Paul E. McKenney wrote: > On Wed, Oct 05, 2016 at 05:18:09PM +0300, Nikolay Borisov wrote: >> >> >> 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 <[email protected]> >>>> --- >>>> >>>> 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? > > Please see below for the current state. > > Thanx, Paul
Splendid, ACK. > > ------------------------------------------------------------------------ > > commit a30cd69bdcb1ae12cb243e75eddd608c1798d438 > Author: Nikolay Borisov <[email protected]> > Date: Thu Oct 6 05:42:39 2016 -0700 > > rcu: RCU_TRACE enables event tracing as well as debugfs > > The commit brings the RCU_TRACE Kconfig option's help text up to date > by noting that it enables additional event tracing as well as debugfs. > > Signed-off-by: Nikolay Borisov <[email protected]> > [ paulmck: Do some wordsmithing. ] > Signed-off-by: Paul E. McKenney <[email protected]> > > diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug > index 2b5441812214..7f8e8f3c72ea 100644 > --- a/lib/Kconfig.debug > +++ b/lib/Kconfig.debug > @@ -1450,7 +1450,8 @@ config RCU_TRACE > select TRACE_CLOCK > help > This option provides tracing in RCU which presents stats > - in debugfs for debugging RCU implementation. > + in debugfs for debugging RCU implementation. It also enables > + additional tracepoints for ftrace-style event tracing. > > Say Y here if you want to enable RCU tracing > Say N if you are unsure. >
