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[GIT/PATCH 0/5] Re: [Xen-devel] unfair servicing of DomU vbd requests

To: Keir Fraser <keir.xen@xxxxxxxxx>
Subject: [GIT/PATCH 0/5] Re: [Xen-devel] unfair servicing of DomU vbd requests
From: Ian Campbell <Ian.Campbell@xxxxxxxxxx>
Date: Thu, 3 Mar 2011 17:09:58 +0000
Cc: Jeremy Fitzhardinge <jeremy@xxxxxxxx>, James Harper <james.harper@xxxxxxxxxxxxxxxx>, xen devel <xen-devel@xxxxxxxxxxxxxxxxxxx>, Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
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On Thu, 2011-03-03 at 08:30 +0000, Keir Fraser wrote: 
> Without the round-robin servicing, unfairness to the point of starvation is
> a distinct possibility.

Indeed. The following is a forward port of these patches from
      * 324:7fe1c6d02a2b 
      * 325:b2768401db94 
      * 988:c88a02a22a05 
      * 990:427276ac595d 
      * 991:9ba6d9f3fbc0

Hopefully I didn't miss any.

The switch in pvops from "l1"/"l2" naming convention to "word"/"bit"
made the conflict resolution a bit prone to thinkos but hopefully I
didn't b0rk it too badly. Review with that in mind greatly appreciated.

boots a dom0 + a pv guest.

Pull request on top of konrad/stable/irq.cleanup:

The following changes since commit c5ae07bb307b658c8458f29ca77d237aec0f9327:
  Ian Campbell (1):
        xen: events: remove dom0 specific xen_create_msi_irq

are available in the git repository at:

  git://xenbits.xen.org/people/ianc/linux-2.6.git irq-fairness

Ian Campbell (1):
      xen: events: Make last processed event channel a per-cpu variable.

Keir Fraser (3):
      xen: events: Clean up round-robin evtchn scan.
      xen: events: Make round-robin scan fairer by snapshotting each l2 word
      xen: events: Remove redundant clear of l2i at end of round-robin loop

Scott Rixner (1):
      xen: events: Process event channels notifications in round-robin order.

 drivers/xen/events.c |   80 +++++++++++++++++++++++++++++++++++++++++++++-----
 1 files changed, 72 insertions(+), 8 deletions(-)


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