From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: RE: [net-next rfc 1/3] net: avoid high order memory allocation for
 queues by using flex array
Date: Wed, 19 Jun 2013 09:28:53 -0700
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Cc: "Michael S. Tsirkin" <mst@redhat.com>,
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To: David Laight <David.Laight@ACULAB.COM>
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On Wed, 2013-06-19 at 17:06 +0100, David Laight wrote:

> Given the number of places I've seen this code added, why
> not put it in a general helper?

Good luck with that. We had many attempts in the past.

> I also thought that malloc() with GFP_KERNEL would sleep.
> Under what conditions does it fail instead?

For example on 32 bit kernel, LOW memory exhaustion/fragmentation.

vmalloc() has an extra 128MB virtual space (on i386 at least with
standard 3G/1G split)