Re: [RFC PATCH] libtraceevent: Increase libtraceevent logging when verbose

From: Steven Rostedt
Date: Thu Jun 10 2021 - 10:39:32 EST


On Wed, 9 Jun 2021 23:06:43 -0700
Ian Rogers <irogers@xxxxxxxxxx> wrote:

> libtraceevent has added more levels of debug printout and with changes
> like:
> https://lore.kernel.org/linux-trace-devel/20210507095022.1079364-3-tz.stoyanov@xxxxxxxxx
> previously generated output like "registering plugin" is no longer
> displayed. This change makes it so that if perf's verbose debug output
> is enabled then the debug and info libtraceevent messages can be
> displayed.
> As this API isn't present in the deprecated tools version of
> libtracevent I'm uploading this as an RFC.

Thanks Ian,

We need to start porting perf to using the upstream libtraceevent
library. I think the best way to do that is what we did with trace-cmd.
That is to have the make files check if the minimum version of
libtraceevent is installed, and if so, use that instead of the local
version. If it is not installed, produce a message encouraging the
developer to install the upstream libtraceevent and warn that it will
be using a deprecated older versino, then build the deprecated local
version. After some time, we could simply remove it and make it a
dependency, but I want to do that when all the main distros being used
have it.

Currently its in the latest Debian, Ubuntu, and Fedora. I also believe
its in SUSE but have not checked. It's in Fedora 34, but it doesn't
appear to be in Fedora 33. As that's not too old, I don't think we
should make it a dependency as of yet.

-- Steve