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From:   SeongJae Park <sjpark@amazon.com>
To:     Jonathan Cameron <Jonathan.Cameron@Huawei.com>
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Subject: Re: Re: [PATCH v6 06/14] mm/damon: Implement access pattern recording
Date:   Tue, 10 Mar 2020 12:55:49 +0100
Message-ID: <20200310115550.24668-1-sjpark@amazon.com>
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On Tue, 10 Mar 2020 09:01:34 +0000 Jonathan Cameron <Jonathan.Cameron@Huawei.com> wrote:

> On Mon, 24 Feb 2020 13:30:39 +0100
> SeongJae Park <sjpark@amazon.com> wrote:
> 
> > From: SeongJae Park <sjpark@amazon.de>
> > 
> > This commit implements the recording feature of DAMON. If this feature
> > is enabled, DAMON writes the monitored access patterns in its binary
> > format into a file which specified by the user. This is already able to
> > be implemented by each user using the callbacks.  However, as the
> > recording is expected to be used widely, this commit implements the
> > feature in the DAMON, for more convenience and efficiency.
> > 
> > Signed-off-by: SeongJae Park <sjpark@amazon.de>
> 
> I guess this work whilst you are still developing, but I'm not convinced
> writing to a file should be a standard feature...

I also not sure whether this is right feature of the kernel or not, but this
would minimize many efforts in user space.  I also thought that this might be
not out of the intention of the 'kernel_write()'.

Nonetheless, this patch could be simply removed, as DAMON supports tracepoints
and the recording can be implemented on user space using it.

Could I ask your other suggestions for this feature?


Thanks,
SeongJae Park

> 
> > ---
[...]