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Message-ID: <cc6f7c1a-13f0-475a-9961-e22e73b13a32@linux.intel.com>
Date: Fri, 22 Dec 2023 10:35:12 +0800
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Subject: Re: [PATCH 1/2] PCI: make pci_dev_is_disconnected() helper public for
 other drivers
To: Lukas Wunner <lukas@wunner.de>
Cc: bhelgaas@google.com, baolu.lu@linux.intel.com, dwmw2@infradead.org,
 will@kernel.org, robin.murphy@arm.com, linux-pci@vger.kernel.org,
 iommu@lists.linux.dev, linux-kernel@vger.kernel.org,
 Haorong Ye <yehaorong@bytedance.com>
References: <20231213034637.2603013-1-haifeng.zhao@linux.intel.com>
 <20231213034637.2603013-2-haifeng.zhao@linux.intel.com>
 <20231213104930.GB31964@wunner.de>
 <31bd82b6-6f7e-4dc4-8cbb-46fa806d699f@linux.intel.com>
 <20231221105124.GC12714@wunner.de>
From: Ethan Zhao <haifeng.zhao@linux.intel.com>
In-Reply-To: <20231221105124.GC12714@wunner.de>
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On 12/21/2023 6:51 PM, Lukas Wunner wrote:
> On Thu, Dec 14, 2023 at 08:58:49AM +0800, Ethan Zhao wrote:
>> On 12/13/2023 6:49 PM, Lukas Wunner wrote:
>>> On Tue, Dec 12, 2023 at 10:46:36PM -0500, Ethan Zhao wrote:
>>>> move pci_dev_is_disconnected() from driver/pci/pci.h to public
>>>> include/linux/pci.h for other driver's reference.
>>>> no function change.
>>> That's merely a prose description of the code.  A reader can already
>>> see from the code what it's doing.  You need to explain the *reason*
>>> for the change instead.  E.g.:  "Make pci_dev_is_disconnected() public
>>> so that it can be called from $DRIVER to speed up hot removal
>>> handling which may otherwise take seconds because of $REASONS."
>> Yup, why I made it public. then how about
>>
>> "Make pci_dev_is_disconnected() public so that it can be called from
>> Intel vt-d driver to check the device's hotplug removal state when
>> issue devTLB flush request."
> Much better.
>
> You may optionally want to point out the location of the file in the
> source tree because not everyone may be familiar where to find the
> "Intel vt-d driver".  Also, not every reader may know where issuing
> of devTLB flush requests occurs, so it might make sense to name the
> function where that happens.  Finally, it is common to adhere to terms
> used in the PCIe Base Spec in commit messages, so "ATC Invalidate Request"
> might be preferable to "devTLB flush request".

ATS Invalidate Request ? devTLB flush request has the same meaning,

I thought all iommu/PCIe guys could understand.


Thanks,

Ethan

>
> Thanks,
>
> Lukas