From: "Tian, Kevin" <kevin.tian@intel.com>
To: Lu Baolu <baolu.lu@linux.intel.com>,
Joerg Roedel <joro@8bytes.org>,
"Raj, Ashok" <ashok.raj@intel.com>,
Christoph Hellwig <hch@infradead.org>,
"Jason Gunthorpe" <jgg@nvidia.com>
Cc: Will Deacon <will@kernel.org>,
Robin Murphy <robin.murphy@arm.com>,
"Liu, Yi L" <yi.l.liu@intel.com>,
"Pan, Jacob jun" <jacob.jun.pan@intel.com>,
"iommu@lists.linux-foundation.org"
<iommu@lists.linux-foundation.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: RE: [PATCH v2 06/12] iommu/vt-d: Acquiring lock in domain ID allocation helpers
Date: Tue, 14 Jun 2022 06:52:22 +0000 [thread overview]
Message-ID: <BN9PR11MB52760A3D7C6BF1AF9C9D34658CAA9@BN9PR11MB5276.namprd11.prod.outlook.com> (raw)
In-Reply-To: <20220614025137.1632762-7-baolu.lu@linux.intel.com>
> From: Lu Baolu <baolu.lu@linux.intel.com>
> Sent: Tuesday, June 14, 2022 10:52 AM
>
> The iommu->lock is used to protect the per-IOMMU domain ID resource.
> Moving the lock into the ID alloc/free helpers makes the code more
> compact. At the same time, the device_domain_lock is irrelevant to
> the domain ID resource, remove its assertion as well.
>
> On the other hand, the iommu->lock is never used in interrupt context,
> there's no need to use the irqsave variant of the spinlock calls.
I still prefer to separating reduction of lock ranges from changing irqsave.
Locking is tricky. From bisect p.o.v. it will be a lot easier if we just change
one logic in one patch.
next prev parent reply other threads:[~2022-06-14 6:52 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-06-14 2:51 [PATCH v2 00/12] iommu/vt-d: Optimize the use of locks Lu Baolu
2022-06-14 2:51 ` [PATCH v2 01/12] iommu/vt-d: debugfs: Remove device_domain_lock usage Lu Baolu
2022-06-14 6:43 ` Tian, Kevin
2022-06-14 7:15 ` Baolu Lu
2022-06-15 1:53 ` Baolu Lu
2022-06-15 6:13 ` Tian, Kevin
2022-06-15 13:02 ` Baolu Lu
2022-06-14 2:51 ` [PATCH v2 02/12] iommu/vt-d: Remove for_each_device_domain() Lu Baolu
2022-06-14 2:51 ` [PATCH v2 03/12] iommu/vt-d: Remove clearing translation data in disable_dmar_iommu() Lu Baolu
2022-06-14 6:49 ` Tian, Kevin
2022-06-14 7:21 ` Baolu Lu
2022-06-15 6:22 ` Tian, Kevin
2022-06-15 13:10 ` Baolu Lu
2022-06-16 4:00 ` Tian, Kevin
2022-06-14 2:51 ` [PATCH v2 04/12] iommu/vt-d: Use pci_get_domain_bus_and_slot() in pgtable_walk() Lu Baolu
2022-06-14 2:51 ` [PATCH v2 05/12] iommu/vt-d: Unnecessary spinlock for root table alloc and free Lu Baolu
2022-06-14 2:51 ` [PATCH v2 06/12] iommu/vt-d: Acquiring lock in domain ID allocation helpers Lu Baolu
2022-06-14 6:52 ` Tian, Kevin [this message]
2022-06-14 7:22 ` Baolu Lu
2022-06-14 2:51 ` [PATCH v2 07/12] iommu/vt-d: Acquiring lock in pasid manipulation helpers Lu Baolu
2022-06-14 2:51 ` [PATCH v2 08/12] iommu/vt-d: Replace spin_lock_irqsave() with spin_lock() Lu Baolu
2022-06-14 6:56 ` Tian, Kevin
2022-06-14 2:51 ` [PATCH v2 09/12] iommu/vt-d: Check device list of domain in domain free path Lu Baolu
2022-06-14 6:57 ` Tian, Kevin
2022-06-14 2:51 ` [PATCH v2 10/12] iommu/vt-d: Fold __dmar_remove_one_dev_info() into its caller Lu Baolu
2022-06-14 7:07 ` Tian, Kevin
2022-06-14 7:44 ` Baolu Lu
2022-06-14 2:51 ` [PATCH v2 11/12] iommu/vt-d: Use device_domain_lock accurately Lu Baolu
2022-06-14 7:16 ` Tian, Kevin
2022-06-14 7:47 ` Baolu Lu
2022-06-14 2:51 ` [PATCH v2 12/12] iommu/vt-d: Convert global spinlock into per domain ones Lu Baolu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=BN9PR11MB52760A3D7C6BF1AF9C9D34658CAA9@BN9PR11MB5276.namprd11.prod.outlook.com \
--to=kevin.tian@intel.com \
--cc=ashok.raj@intel.com \
--cc=baolu.lu@linux.intel.com \
--cc=hch@infradead.org \
--cc=iommu@lists.linux-foundation.org \
--cc=jacob.jun.pan@intel.com \
--cc=jgg@nvidia.com \
--cc=joro@8bytes.org \
--cc=linux-kernel@vger.kernel.org \
--cc=robin.murphy@arm.com \
--cc=will@kernel.org \
--cc=yi.l.liu@intel.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).