From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jesper Dangaard Brouer <brouer@redhat.com>
Subject: Re: [Lsf] [Lsf-pc] [LSF/MM TOPIC] Generic page-pool recycle
 facility?
Date: Mon, 11 Apr 2016 20:37:38 +0200
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Cc: Matthew Wilcox <willy@linux.intel.com>,
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To: Thadeu Lima de Souza Cascardo <cascardo@redhat.com>
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On Mon, 11 Apr 2016 14:46:25 -0300
Thadeu Lima de Souza Cascardo <cascardo@redhat.com> wrote:

> So, Jesper, please take into consideration that this pool design
> would rather be per device. Otherwise, we allow some device to write
> into another's device/driver memory.

Yes, that was my intended use.  I want to have a page-pool per device.
I actually, want to go as far as a page-pool per NIC HW RX-ring queue.

Because the other use-case for the page-pool is zero-copy RX.

The NIC HW trick is that we today can create a HW filter in the NIC
(via ethtool) and place that traffic into a separate RX queue in the
NIC.  Lets say matching NFS traffic or guest traffic. Then we can allow
RX zero-copy of these pages, into the application/guest, somehow
binding it to RX queue, e.g. introducing a "cross-domain-id" in the
page-pool page that need to match.

-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Principal Kernel Engineer at Red Hat
  Author of http://www.iptv-analyzer.org
  LinkedIn: http://www.linkedin.com/in/brouer