From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sasha Levin <sasha.levin@oracle.com>
Subject: Re: mm: shm: hang in shmem_fallocate
Date: Sun, 09 Feb 2014 20:41:54 -0500
Message-ID: <52F82E62.2010709@oracle.com>
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Cc: Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
	linux-fsdevel@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>
To: Hugh Dickins <hughd@google.com>, Dave Jones <davej@redhat.com>
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On 02/08/2014 10:25 PM, Hugh Dickins wrote:
 > Would trinity be likely to have a thread or process repeatedly faulting
 > in pages from the hole while it is being punched?

I can see how trinity would do that, but just to be certain - Cc davej.

On 02/08/2014 10:25 PM, Hugh Dickins wrote:
 > Does this happen with other holepunch filesystems?  If it does not,
 > I'd suppose it's because the tmpfs fault-in-newly-created-page path
 > is lighter than a consistent disk-based filesystem's has to be.
 > But we don't want to make the tmpfs path heavier to match them.

No, this is strictly limited to tmpfs, and AFAIK trinity tests hole
punching in other filesystems and I make sure to get a bunch of those
mounted before starting testing.


Thanks,
Sasha