Re: [PATCH v2] malloc: Remove malloc hooks (Bug 23328)

[Carlos O'Donell <carlos at redhat dot com>]

On 07/23/2018 11:54 AM, Joseph Myers wrote:
> On Fri, 20 Jul 2018, Carlos O'Donell wrote:
> 
>> Joseph,
>>
>> Does this design of this patch implement what you thought would be
>> an appropriate solution to deprecating the hooks? Part of this design
>> is based on your feedback that you wanted to see some kind of shared
>> library that provided the features that the hooks used to provide,
>> and that's what we do here as we finalize (make compat symbolis) the
>> hooks and other APIs.
> 
> Having a library providing the functionality required to use mtrace 
> accords with my expectations, yes.  (This is not a more general design 
> review of the patch.)

OK, thank you, I just wanted to make sure that we were still in line with
what you were expecting. You expressed an opinion on the patches originally
and so I counted you among those developers with a concerned opinion on the
class of changes we were making.

I think there is a class of API which will always be useful, like mtrace
and muntrace, but by default they will do nothing, then you preload libmalloc-extras.so
and they start working. We have enough technology in place from the tracer
that DJ/Florian/I built that we can deliver a thread-safe version that is
very fast (faster for local use than lttng-ust, but with less features).

Cheers,
Carlos.