Re: [PATCH v12 4/5] iommu/vt-d: pass pdev parameter for qi_check_fault() and refactor callers

From: Ethan Zhao <haifeng.zhao@linux.intel.com>
To: "Tian, Kevin" <kevin.tian@intel.com>,
	"baolu.lu@linux.intel.com" <baolu.lu@linux.intel.com>,
	"bhelgaas@google.com" <bhelgaas@google.com>,
	"robin.murphy@arm.com" <robin.murphy@arm.com>,
	"jgg@ziepe.ca" <jgg@ziepe.ca>
Cc: "dwmw2@infradead.org" <dwmw2@infradead.org>,
	"will@kernel.org" <will@kernel.org>,
	"lukas@wunner.de" <lukas@wunner.de>,
	"Liu, Yi L" <yi.l.liu@intel.com>,
	"iommu@lists.linux.dev" <iommu@lists.linux.dev>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"linux-pci@vger.kernel.org" <linux-pci@vger.kernel.org>
Subject: Re: [PATCH v12 4/5] iommu/vt-d: pass pdev parameter for qi_check_fault() and refactor callers
Date: Tue, 30 Jan 2024 15:30:39 +0800	[thread overview]
Message-ID: <b3af83cf-b6c7-4543-b793-f2a9547ca9d2@linux.intel.com> (raw)
In-Reply-To: <BN9PR11MB5276BAB9620D3A7B07B24F328C7E2@BN9PR11MB5276.namprd11.prod.outlook.com>

On 1/29/2024 4:58 PM, Tian, Kevin wrote:
>> From: Ethan Zhao <haifeng.zhao@linux.intel.com>
>> Sent: Monday, January 29, 2024 11:49 AM
>>
>> to check state of ATS capable pci device in qi_check_fault() for surprise
>> removal case, we need to pass the target pci device of ATS invalidation
>> request to qi_check_fault(). if pdev is valid, means current request is for
>> ATS invalidation, vice vesa.
>>
>> no function change.
> qi_submit_sync() is used for all kinds of iotlb/cache/devtlb invalidations.
> it's a bit weird to see a device pointer (even being NULL) in places where
> a device doesn't even matter.
>
> having a new qi_submit_sync_devtlb() wrapper sounds cleaner to me,
> with an internal __qi_submit_sync() helper to accept a device pointer.
>
> qi_submit_sync() calls __qi_submit_sync() with a null device pointer then
> non-devtlb paths are intact.

Make sense !

That way, could keep about 10 qi_submit_sync() calling intact, while

only 2-3 qi_submit_sync_devtlb() wrapper calling needed.

Thanks,

Ethan