[DTrace-devel] [PATCH v2 08/20] providers: allow providers with no trampoline

[Nick Alcock]

On 20 Sep 2022, Kris Van Hees uttered the following:

> On Wed, Sep 07, 2022 at 01:59:56PM +0100, Nick Alcock via DTrace-devel wrote:
>> Such providers can be enabled just like any other, but generate no code.
>> 
>> Meant for use by things like the pid provider which have two probes
>> associated with each system-side probe, one of which gets fired and
>> generates code for the others in its trampoline method. Right now, both
>> probes get the same trampoline, but only one probe's trampoline is
>> necessary. Doing this lets us drop the unnecessary ones in a future
>> commit.
>
> This is not quite accurate.  Perhaps just omit this and simply mention that
> the patch is needed to support providers that do not generate trampoline code
> for their probes (because the probes are alises for probes in an provider that
> takes care of the trampoline code generatopn)?

OK, and yeah that's just wrong given what I now understand about the pid
provider's operation.

Adjusted the last para to:
> Meant for use by providers like pid which have some probes without
> trampolines (but which enable other probes which do contain trampolines
> that execute on their behalf).  Both such probes need enabling because
> we want to ensure their names are interned, etc: we only want to avoid
> trying to execute their trampoline when there is none.

>> Signed-off-by: Nick Alcock <nick.alcock at oracle.com>
>
> Reviewed-by: Kris Van Hees <kris.van.hees at oracle.com>
>
> ... assuming you fix the commit message as outlined above.

(hope that's good enough)