From mboxrd@z Thu Jan  1 00:00:00 1970
From: rusty@rustcorp.com.au (Rusty Russell)
Date: Wed, 25 Mar 2009 11:43:11 +1030
Subject: [ltt-dev] [patch 7/9] LTTng instrumentation - kernel
In-Reply-To: <20090324183313.GH31117@elte.hu>
References: <20090324155625.420966314@polymtl.ca>
	<20090324160148.872305963@polymtl.ca>
	<20090324183313.GH31117@elte.hu>
Message-ID: <200903251143.12472.rusty@rustcorp.com.au>

On Wednesday 25 March 2009 05:03:13 Ingo Molnar wrote:
> 
> (Rusty Cc:-ed - for the module.c tracepoints below)

Thanks, tho they look fine and non-intrusive to me.

> I believe that to have a complete picture of module usage, module 
> refcount get/put events should be included as well, beyond the basic 
> load/free events.
> 
> These both have performance impact (a module get/put in a fastpath 
> hurts scalability), and are informative in terms of establishing the 
> module dependency graph.

A module_get()/put() should not hurt scalability at all!  I went to great and
horrible lengths to ensure that was the case since the rewrite in 2.4.

But a module dependency graph et. al. would be kind of cool.

Thanks,
Rusty.