[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] [PATCH 2/3 v2] Refactor msi/msix restore code Part2

On 2013-08-24 01:15, Konrad Rzeszutek Wilk wrote:
On Thu, Aug 22, 2013 at 03:14:34PM -0600, Bjorn Helgaas wrote:
On Mon, Aug 5, 2013 at 1:21 AM, Zhenzhong Duan
<zhenzhong.duan@xxxxxxxxxx>  wrote:
xen_initdom_restore_msi_irqs trigger a hypercall to restore addr/data/mask
in dom0. It's better to do the same in default_restore_msi_irqs for baremetal.

Move restore of mask in default_restore_msi_irqs, this could avoid mask
restored twice in dom0, and the logic for baremetal keep same.

First mask restore is in xen_initdom_restore_msi_irqs->PHYSDEVOP_restore_msi,
Second restore is __pci_restore_msix_state->msix_mask_irq.

Mask bits are under full control of xen, and the entry->masked in dom0 kernel
is invalid. restore an invalid value to mask register could mask the msix

Without fix, qlcnic driver calling pci_reset_function will lost interrupt
in dom0.
Konrad, this changelog still doesn't make any sense to me, but if you
ack this, I guess I can apply it.
Hey Bjorn,

Zhenzhong is patiently working to rewrite up the commit message based on
my naive questions and emails back and forth. Once it is good shape he
will post it. The code will look the same but the commit message will
be a bit more verbose and clear.

Is there an ETA when you would like these? I recall the merge window
is just around the corner - so when is your comfortable cut-off-day
so that you can make a go/no-go decision?

I guess there are also:

   Jul 24  [PATCH 1/3] Refactor msi/msix restore code Part1
   Jul 30  [PATCH 3/3 v2] Update x86_msi.restore_msi_irqs API param

and all three should be applied as a series?
<scratches his head>.

I think the
    Jul 30  [PATCH 3/3 v2] Update x86_msi.restore_msi_irqs API param

can go in anytime. That is mostly a cosmetic fixup in the API.
Zhenzhong - right?
Yes, 3rd patch doesn't depend on the first two.
One effect is making code looks consistent. But my main purpose is optimizing
msix restore code in initial domain.
Before patch, dom0 calls PHYSDEVOP_restore_msi hypercall for every entry in
dev->msi_list, now it calls PHYSDEVOP_restore_msi hypercall once.

Xen-devel mailing list



Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.