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Subject: Re: [RFC] [PATCH] mtd: add tracepoints for mtd_read and mtd_write
To: Brian Norris <computersforpeace@gmail.com>,
 Richard Weinberger <richard.weinberger@gmail.com>
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From: Daniel Walter <dwalter@sigma-star.at>
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Date: Thu, 14 Jan 2016 02:12:15 +0100
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On 01/08/2016 06:57 PM, Brian Norris wrote:
> On Fri, Jan 08, 2016 at 10:33:03AM +0100, Richard Weinberger wrote:
>> On Tue, Nov 17, 2015 at 8:18 PM, Daniel Walter <dwalter@sigma-star.at> wrote:
>>> Add tracepoints to mtd subsystem for read and write
>>> operations. This should allow us to identify applications
>>> which are generating too much reads/writes on a flash-device.
>>>
>>> Signed-off-by: Daniel Walter <dwalter@sigma-star.at>
>>
>> Brian, any comments on this?
> 
> Only a few. I'm not very familiar with writing trace events. I've only
> barely used them! And I haven't run this patch yet.
> 
> But I thought Daniel reported having some difficulty here -- that it
> isn't actually that useful to get real "user" information, since most
> writing/erasing happens from background UBI tasks in practice. So is
> this still the best mechanism for tracking this information? (Even if
> there's better ways to get info directly out of UBI, I guess maybe it'd
> still be good to have this infrastructure.)
> 
> Also, maybe I'm missing something, but it doesn't look like this
> attempts to record *which* MTD is being accessed, right? I'd think
> logging mtd->name could help?
> 
> Brian
> 
Hi,

sorry for the late reply, filters ate your mail :/
I'll add mtd->name, since this sounds like a great idea.
regarding your other mail (mtd_erase/read/write_oob), I'll add
tracepoints for them as well (they have been on my list anyway).

Thanks for the input, expect a v2 later this week.

cheers,

daniel