[ltt-dev] LTTng-UST tracepoint API updates

[Mathieu Desnoyers]

* Matthew Khouzam (matthew.khouzam at ericsson.com) wrote:
> 
> 
> On 11-11-14 05:09 PM, Mathieu Desnoyers wrote:
> > * Matthew Khouzam (matthew.khouzam at ericsson.com) wrote:
> >> To clarify:
> >> A tracepoint event now takes
> >> provider name /*a string no spaces, starts with a letter, alpha numeric
> >> + _. */
> >> the event name /* same as above */
> >> TP_ARGS( type , arg , ... ) /* every odd element is the type of the
> >> argument in the next place, must be a c type, not void... that's looking
> >> for trouble */
> > yep. Although we might be able to deal with TP_ARGS(void) without much
> > problem, but I'd need to adapt the code to support it.

TP_ARGS(void) is now supported too:

commit 992abe1193e04da4c224f74fbe0e5c3aeb9bfeb5
Author: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>
Date:   Mon Nov 14 20:01:36 2011 -0500

    tracepoint: support TP_ARGS(void)
    
    Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>

Thanks,

Mathieu

> >
> >>                                          /* every even element is the
> >> name of the argument */
> >>                                          /* theres always an even number
> >> of args */
> >> TP_FIELDS( ctf_type( type, fieldname, arg) ... ));
> >>
> >> I like the improvements... I don't know if it's just me, but this makes
> >> TP_ARGS and ctf_type much more harmonized, IMO.
> > agreed.
> >
> >> Why is ctf_type not CTF_TYPE, it is a macro and can be clearer to the
> >> user that the args need not be declared, they can be strings without
> >> quotes or types? I'm sure you have a well thought out answer. :)
> > too much CAPS makes my eyes hurt ;)
> >
> >> I really like that TP_ARGS() works.
> >
> > :)
> 
> To better clarify, I really like that tp_args_noargs has been banished.
> >
> > Mathieu
> >>
> >>
> >>
> >>
> >> On 11-11-13 02:12 PM, Mathieu Desnoyers wrote:
> >>> * Mathieu Desnoyers (mathieu.desnoyers at efficios.com) wrote:
> >>>> Hi,
> >>>>
> >>>> I introduced the following API changes for LTTng-UST, after receiving
> >>>> very appropriate feedback:
> >>>>
> >>>>     Tracepoint API change: rename TRACEPOINT_SYSTEM to TRACEPOINT_PROVIDER
> >>>>     
> >>>>     Eliminates the confusion between the first TRACEPOINT_EVENT "provider"
> >>>>     argument and the "TRACEPOINT_SYSTEM", which need to be the same thing.
> >>>>     
> >>>> and made sure TRACEPOINT_PROVIDER always match TRACEPOINT_SYSTEM by
> >>>> adding a compiler warning:
> >>>>
> >>>>     Tracepoints: add provider mismatch check
> >>>>     
> >>>> Finally, rename TP_ARGS to TP_VARS, in preparation for combining
> >>>> TP_PROTO and TP_ARGS:
> >>>>
> >>>>     tracepoint API change: rename TP_ARGS to TP_VARS
> >>>>     
> >>>>     In preparation of folding of both TP_PROTO and TP_ARGS into TP_ARGS.
> >>>>
> >>>> Hopefully I'll succeed to getting both TP_PROTO and TP_VARS combined
> >>>> into TP_ARGS, but even if this does not work out, TP_VARS seems much
> >>>> more appropriate than TP_ARGS here.
> >>> The API change is completed by the following commit:
> >>>
> >>> commit 63ef26930fe613a266cc69f5089cf643dd59b012
> >>> Author: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>
> >>> Date:   Sun Nov 13 14:07:57 2011 -0500
> >>>
> >>>     Tracepoint API change: combine TP_PROTO and TP_VARS into TP_ARGS, remove _NOARGS macros
> >>>     
> >>>     New API for tracepoints, combining the TP_PROTO and TP_VARS arguments
> >>>     into a single "TP_ARGS" macro. It takes up to 10 parameters (from 0 to
> >>>     10). The "_NOARGS" special-case is not needed anymore: it can be
> >>>     achieved simply by passing an empty TP_ARGS:
> >>>     
> >>>       TP_ARGS(),
> >>>     
> >>>     to the standard tracepoint event declarations.
> >>>     
> >>>     Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>
> >>>
> >>> Best regards,
> >>>
> >>> Mathieu
> >>>
> >>>> Thanks,
> >>>>
> >>>> Mathieu
> >>>>
> >>>> -- 
> >>>> Mathieu Desnoyers
> >>>> Operating System Efficiency R&D Consultant
> >>>> EfficiOS Inc.
> >>>> http://www.efficios.com
> >> _______________________________________________
> >> ltt-dev mailing list
> >> ltt-dev at lists.casi.polymtl.ca
> >> http://lists.casi.polymtl.ca/cgi-bin/mailman/listinfo/ltt-dev
> >>
> 

-- 
Mathieu Desnoyers
Operating System Efficiency R&D Consultant
EfficiOS Inc.
http://www.efficios.com