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Date:   Mon, 10 Aug 2020 17:04:53 +0200
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Eugene Lubarsky <elubarsky.linux@gmail.com>
Cc:     linux-api@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org, adobriyan@gmail.com,
        avagin@gmail.com, dsahern@gmail.com
Subject: Re: [RFC PATCH 0/5] Introduce /proc/all/ to gather stats from all
 processes
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References: <20200810145852.9330-1-elubarsky.linux@gmail.com>
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On Tue, Aug 11, 2020 at 12:58:47AM +1000, Eugene Lubarsky wrote:
> This is an idea for substantially reducing the number of syscalls needed
> by monitoring tools whilst mostly re-using the existing API.

How many syscalls does this save on?

Perhaps you want my proposed readfile(2) syscall:
	https://lore.kernel.org/r/20200704140250.423345-1-gregkh@linuxfoundation.org
to help out with things like this?  :)

> The proposed files in this proof-of-concept patch set are:
> 
> * /proc/all/stat

I think the problem will be defining "all" in the case of the specific
namespace you are dealing with, right?  How will this handle all of
those issues properly for all of these different statisics?

thanks,

greg k-h