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Date: Tue, 27 Jul 2010 10:27:49 +0200
From: Robert Richter <robert.richter@amd.com>
To: Lin Ming <ming.m.lin@intel.com>
CC: Ingo Molnar <mingo@elte.hu>, Corey Ashford <cjashfor@linux.vnet.ibm.com>,
        Johannes Berg <johannes@sipsolutions.net>,
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        Frederic Weisbecker <fweisbec@gmail.com>,
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        lkml <linux-kernel@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Steven Rostedt <rostedt@goodmis.org>
Subject: Re: [RFC][PATCH v1 02/15] perf: export generic hardware events via
 sysfs
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On 26.07.10 22:18:23, Lin Ming wrote:

> > > /sys/devices/system/cpu/cpu0/events
> > > |-- L1-dcache-load-misses
> > > |   |-- config
> > > |   `-- type

vs.

> >  |-- L1-dcache-load-misses  ===> event name
> >  |   `-- id                 ===> event id

> > This is very simple and flexible and solves the original problem too.
> 
> Yeah, this is flexible. I'll think about this closely.

The thing is, if you start introducing the config/type i/f, we will
stick with it for a long time. I want to avoid this from the
beginning.

Using an id only would work with your current implementation too, you
only need to maintain an id -> config/type mapping, maybe in some
private data section, without exporting it to userspace.

-Robert

-- 
Advanced Micro Devices, Inc.
Operating System Research Center