Subject: Re: Kernel marker has no performance impact on ia64.
From: Peter Zijlstra <peterz@infradead.org>
To: "Frank Ch. Eigler" <fche@redhat.com>
Cc: Masami Hiramatsu <mhiramat@redhat.com>,
       Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>,
       Hideo AOKI <haoki@redhat.com>, mingo@elte.hu,
       linux-kernel@vger.kernel.org, Steven Rostedt <rostedt@goodmis.org>
In-Reply-To: <20080612164318.GB17814@redhat.com>
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Date: Thu, 12 Jun 2008 18:56:18 +0200
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On Thu, 2008-06-12 at 12:43 -0400, Frank Ch. Eigler wrote:

> This is another reason why markers are a nice solution.  They allow
> passing of actual useful values: not just the %p pointers but the most
> interesting derived values (e.g., prev->pid). 

Useful to whoem? stap isn't the holy grail of tracing and certainly not
the only consumer of trace points, so restricting the information to
just what stap needs is actually making trace points less useful.

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