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Subject: Re: [PATCH RFC 00/77] Re-design MSI/MSI-X interrupts enablement
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From: Ben Hutchings <bhutchings@solarflare.com>
To: Alexander Gordeev <agordeev@redhat.com>
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Date: Mon, 7 Oct 2013 21:48:01 +0100
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On Sun, 2013-10-06 at 09:10 +0200, Alexander Gordeev wrote:
> On Sun, Oct 06, 2013 at 05:19:46PM +1100, Benjamin Herrenschmidt wrote:
> > On Sun, 2013-10-06 at 08:02 +0200, Alexander Gordeev wrote:
> > > In fact, in the current design to address the quota race decently the
> > > drivers would have to protect the *loop* to prevent the quota change
> > > between a pci_enable_msix() returned a positive number and the the next
> > > call to pci_enable_msix() with that number. Is it doable?
> > 
> > I am not advocating for the current design, simply saying that your
> > proposal doesn't address this issue while Ben's does.
> 
> There is one major flaw in min-max approach - the generic MSI layer
> will have to take decisions on exact number of MSIs to request, not
> device drivers.
[...

No, the min-max functions should be implemented using the same loop that
drivers are expected to use now.

Ben.

-- 
Ben Hutchings, Staff Engineer, Solarflare
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.