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Subject: Re: [PATCH 1/7] PCI/DPC: Leave interrupts enabled while handling
 event
To: Keith Busch <keith.busch@intel.com>,
        Linux PCI <linux-pci@vger.kernel.org>,
        Bjorn Helgaas <bhelgaas@google.com>
Cc: Oza Pawandeep <poza@codeaurora.org>
References: <20180620213833.25072-1-keith.busch@intel.com>
From: Sinan Kaya <okaya@codeaurora.org>
Message-ID: <801facdf-dbdf-12c1-c470-a97db065b232@codeaurora.org>
Date: Wed, 20 Jun 2018 17:42:51 -0400
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On 6/20/2018 5:38 PM, Keith Busch wrote:
> Now that the DPC driver clears the interrupt status before exiting the
> irq handler, we don't need to abuse the DPC control register to know if
> a shared interrupt is for a new DPC event: a DPC port can not trigger
> a second interrupt until the host clears the trigger status later in the
> work queue handler.
> 
> Signed-off-by: Keith Busch <keith.busch@intel.com>

Isn't this a problem with legacy interrupts on the root ports with no MSI?
(can be tested with pci=nomsi)

DPC interrupt handler gets called for all service driver interrupts like AER, PME and
HP.

-- 
Sinan Kaya
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.