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Date: Thu, 5 Dec 2013 15:26:38 -0800
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Christopher Covington <cov@codeaurora.org>
Cc: Adrien =?iso-8859-1?Q?Verg=E9?= <adrienverge@gmail.com>,
        Russell King <linux@arm.linux.org.uk>,
        Randy Dunlap <rdunlap@infradead.org>,
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        Dietmar Eggemann <dietmar.eggemann@arm.com>,
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        "zhangwei(Jovi)" <jovi.zhangwei@huawei.com>
Subject: Re: [PATCH 0/3] ARM Coresight: Enhance ETM tracing control
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On Thu, Dec 05, 2013 at 05:45:12PM -0500, Christopher Covington wrote:
> On 12/05/2013 03:16 PM, Greg Kroah-Hartman wrote:
> > On Thu, Dec 05, 2013 at 03:12:50PM -0500, Christopher Covington wrote:
> [...]
> > And adding new features to code that is "dead" and should probably be
> > removed isn't a good idea, as I'm sure you can understand.
> 
> I would consider feature additions to be a sign of life. Maybe the
> architecture or user interface isn't ideal, but would you suggest just as
> quickly for media codec or cryptography hardware support be removed?

No, but I would ask that they be moved to use the same userspace api
for the same functionality, and not create custom ones just because
"they can".

> > How much work is it to incorportate ETM into the perf framework?  Don't
> > you think that this is a better thing to do overall, instead of having
> > duplicating interfaces for the same thing?
> 
> I'm not familiar enough with the ETM hardware (and the ETB, the buffer where
> the data is stored) and driver to say. One factor may be whether the perf
> events framework would need to be extended for complete functionality or could
> be used as-is.

How about moving this conversation to the proper mailing list for this
type of thing then?

thanks,

greg k-h