From: Nicolin Chen <nicolinc@nvidia.com>
To: Pranjal Shrivastava <praan@google.com>
Cc: <will@kernel.org>, <robin.murphy@arm.com>, <jgg@nvidia.com>,
<joro@8bytes.org>, <bhelgaas@google.com>, <kevin.tian@intel.com>,
<kees@kernel.org>, <smostafa@google.com>,
<baolu.lu@linux.intel.com>,
<linux-arm-kernel@lists.infradead.org>, <iommu@lists.linux.dev>,
<linux-kernel@vger.kernel.org>, <linux-pci@vger.kernel.org>,
<skaestle@nvidia.com>, <mmarrid@nvidia.com>,
<skolothumtho@nvidia.com>, <bbiber@nvidia.com>
Subject: Re: [PATCH v2 03/11] iommu/arm-smmu-v3: Add arm_smmu_drain_queue_for_iopf() helper
Date: Tue, 28 Jul 2026 22:26:19 -0700 [thread overview]
Message-ID: <ammO+4W/dGC8kTCr@nvidia.com> (raw)
In-Reply-To: <ammMf5z-Gl-Wygk6@google.com>
On Wed, Jul 29, 2026 at 05:15:43AM +0000, Pranjal Shrivastava wrote:
> For PRIQ/EVTQ, my only worry was the HW producing more events,
> say Device A is detached (we call drain from attach_release) but Device B
> (still attached) starts an agressive DMA with multiple PRI requests/evts.
>
> Maybe we should go back to snapshot based polling for that?
If you look closely, "pending" is the snapshot, regardless of the
growing prod.
* With @until_empty == false (for EVTQ/PRIQ), exit once "drained" reaches its
* target: "pending" (i.e. prod0 - cons0, frozen at the entry time):
*
* cons0 cons prod0 (prod)
* |<---- drained ---->| | |
* ---+###################+=====================+=============+--->
* |<--------------- pending --------------->|
Nicolin
next prev parent reply other threads:[~2026-07-29 5:26 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-05-28 7:59 [PATCH v2 00/11] iommu/arm-smmu-v3: Add PRI support Nicolin Chen
2026-05-28 7:59 ` [PATCH v2 01/11] iommu/arm-smmu-v3: Add arm_smmu_attach_release() Nicolin Chen
2026-05-28 7:59 ` [PATCH v2 02/11] iommu/arm-smmu-v3: Factor out __queue_empty() and __queue_consumed() Nicolin Chen
2026-05-28 7:59 ` [PATCH v2 03/11] iommu/arm-smmu-v3: Add arm_smmu_drain_queue_for_iopf() helper Nicolin Chen
2026-07-28 21:16 ` Pranjal Shrivastava
2026-07-28 22:17 ` Nicolin Chen
2026-07-29 5:15 ` Pranjal Shrivastava
2026-07-29 5:26 ` Nicolin Chen [this message]
2026-07-29 5:46 ` Pranjal Shrivastava
2026-07-29 16:47 ` Nicolin Chen
2026-07-29 17:00 ` Pranjal Shrivastava
2026-05-28 7:59 ` [PATCH v2 04/11] iommu/arm-smmu-v3: Drain in-flight fault handlers Nicolin Chen
2026-05-28 7:59 ` [PATCH v2 05/11] iommu/arm-smmu-v3: Submit CMDQ_OP_PRI_RESP for IOPF event Nicolin Chen
2026-06-26 16:15 ` Robin Murphy
2026-06-27 0:44 ` Nicolin Chen
2026-05-28 7:59 ` [PATCH v2 06/11] iommu/arm-smmu-v3: Support PRI Page Request in arm_smmu_handle_ppr() Nicolin Chen
2026-05-28 7:59 ` [PATCH v2 07/11] iommu/arm-smmu-v3: Disable PRI when no IRQ handler is registered Nicolin Chen
2026-05-28 7:59 ` [PATCH v2 08/11] iommu/arm-smmu-v3: Allocate IOPF queue for ARM_SMMU_FEAT_PRI Nicolin Chen
2026-05-28 7:59 ` [PATCH v2 09/11] PCI/ATS: Add PRI stubs Nicolin Chen
2026-05-28 7:59 ` [PATCH v2 10/11] PCI/ATS: Export pci_enable_pri() and pci_reset_pri() Nicolin Chen
2026-05-28 7:59 ` [PATCH v2 11/11] iommu/arm-smmu-v3: Enable PRI for PCI device in arm_smmu_probe_device() Nicolin Chen
2026-06-26 14:54 ` [PATCH v2 00/11] iommu/arm-smmu-v3: Add PRI support harsha.v
2026-06-27 0:43 ` Nicolin Chen
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=ammO+4W/dGC8kTCr@nvidia.com \
--to=nicolinc@nvidia.com \
--cc=baolu.lu@linux.intel.com \
--cc=bbiber@nvidia.com \
--cc=bhelgaas@google.com \
--cc=iommu@lists.linux.dev \
--cc=jgg@nvidia.com \
--cc=joro@8bytes.org \
--cc=kees@kernel.org \
--cc=kevin.tian@intel.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pci@vger.kernel.org \
--cc=mmarrid@nvidia.com \
--cc=praan@google.com \
--cc=robin.murphy@arm.com \
--cc=skaestle@nvidia.com \
--cc=skolothumtho@nvidia.com \
--cc=smostafa@google.com \
--cc=will@kernel.org \
/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