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From: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
To: Michal Hocko <mhocko@kernel.org>
CC: Andrew Morton <akpm@linux-foundation.org>,
        David Rientjes <rientjes@google.com>,
        =?utf-8?B?SsO2cm4gRW5nZWw=?= <joern@purestorage.com>,
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        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Naoya Horiguchi <nao.horiguchi@gmail.com>
Subject: Re: [PATCH v5 2/2] mm: hugetlb: proc: add HugetlbPages field to
 /proc/PID/status
Thread-Topic: [PATCH v5 2/2] mm: hugetlb: proc: add HugetlbPages field to
 /proc/PID/status
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Date: Thu, 20 Aug 2015 23:34:51 +0000
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On Thu, Aug 20, 2015 at 01:00:05PM +0200, Michal Hocko wrote:
> On Thu 20-08-15 08:26:27, Naoya Horiguchi wrote:
> > Currently there's no easy way to get per-process usage of hugetlb pages,
> 
> Is this really the case after your previous patch? You have both 
> HugetlbPages and KernelPageSize which should be sufficient no?

We can calcurate it from these info, so saying "no easy way" was incorrect :(

> Reading a single file is, of course, easier but is it really worth the
> additional code? I haven't really looked at the patch so I might be
> missing something but what would be an advantage over reading
> /proc/<pid>/smaps and extracting the information from there?

My first idea was just "users should feel it useful", but permission as David
commented sounds a good technical reason to me.

Thanks,
Naoya Horiguchi????{.n?+???????+%?????ݶ??w??{.n?+????{??G?????{ay?ʇڙ?,j??f???h?????????z_??(?階?ݢj"???m??????G????????????&???~???iO???z??v?^?m????????????I?