Date: Wed, 4 Sep 2013 10:55:59 -0400
From: Tejun Heo <tj@kernel.org>
To: Alexander Gordeev <agordeev@redhat.com>
Cc: linux-kernel@vger.kernel.org, x86@kernel.org, linux-pci@vger.kernel.org,
        linux-ide@vger.kernel.org, Ingo Molnar <mingo@kernel.org>,
        Joerg Roedel <joro@8bytes.org>, Jan Beulich <JBeulich@suse.com>,
        Bjorn Helgaas <bhelgaas@google.com>
Subject: Re: [PATCH 3/4] AHCI: Conserve interrupts with
 pci_enable_msi_block_part() interface
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Hello,

On Wed, Sep 04, 2013 at 09:22:57AM +0200, Alexander Gordeev wrote:
> I think a general approach that will cover it all (including ICH and undesired
> sharing of interrupt vectors) - start MME from roundup_pow_of_two(n_ports) and
> ensure MRSM bit is unset. If not - double MME and retry. If still not and the
> limit is reached - fall back to single MSI.
> 
> Makes sense?

Ugh... I really don't want this sort of retry loop.  I'm still a bit
lost on why this is necessary.  Can you please elaborate?

Thanks.

-- 
tejun
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