From: Will Deacon <will@kernel.org>
To: Rob Clark <robdclark@gmail.com>
Cc: Rob Clark <robdclark@chromium.org>,
Robin Murphy <robin.murphy@arm.com>,
open list <linux-kernel@vger.kernel.org>,
iommu@lists.linux-foundation.org, linux-arm-msm@vger.kernel.org,
freedreno@lists.freedesktop.org,
"moderated list:ARM SMMU DRIVERS"
<linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH] iommu/arm-smmu: avoid pathological RPM behaviour for unmaps
Date: Fri, 1 Nov 2019 16:28:24 +0000 [thread overview]
Message-ID: <20191101162824.GB3603@willie-the-truck> (raw)
In-Reply-To: <20191031213102.17108-1-robdclark@gmail.com>
On Thu, Oct 31, 2019 at 02:31:02PM -0700, Rob Clark wrote:
> From: Rob Clark <robdclark@chromium.org>
>
> When games, browser, or anything using a lot of GPU buffers exits, there
> can be many hundreds or thousands of buffers to unmap and free. If the
> GPU is otherwise suspended, this can cause arm-smmu to resume/suspend
> for each buffer, resulting 5-10 seconds worth of reprogramming the
> context bank (arm_smmu_write_context_bank()/arm_smmu_write_s2cr()/etc).
> To the user it would appear that the system just locked up.
>
> A simple solution is to use pm_runtime_put_autosuspend() instead, so we
> don't immediately suspend the SMMU device.
>
> Signed-off-by: Rob Clark <robdclark@chromium.org>
> ---
> drivers/iommu/arm-smmu.c | 16 +++++++++++++++-
> 1 file changed, 15 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
> index 7c503a6bc585..5abc0d210d90 100644
> --- a/drivers/iommu/arm-smmu.c
> +++ b/drivers/iommu/arm-smmu.c
> @@ -122,7 +122,7 @@ static inline int arm_smmu_rpm_get(struct arm_smmu_device *smmu)
> static inline void arm_smmu_rpm_put(struct arm_smmu_device *smmu)
> {
> if (pm_runtime_enabled(smmu->dev))
> - pm_runtime_put(smmu->dev);
> + pm_runtime_put_autosuspend(smmu->dev);
> }
>
> static struct arm_smmu_domain *to_smmu_domain(struct iommu_domain *dom)
> @@ -1154,6 +1154,20 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
> /* Looks ok, so add the device to the domain */
> ret = arm_smmu_domain_add_master(smmu_domain, fwspec);
>
> + /*
> + * Setup an autosuspend delay to avoid bouncing runpm state.
> + * Otherwise, if a driver for a suspendend consumer device
I fixed this typo and applied with Robin's reviewed-by from before.
Will
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
prev parent reply other threads:[~2019-11-01 16:28 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-31 21:31 [PATCH] iommu/arm-smmu: avoid pathological RPM behaviour for unmaps Rob Clark
2019-11-01 16:28 ` Will Deacon [this message]
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=20191101162824.GB3603@willie-the-truck \
--to=will@kernel.org \
--cc=freedreno@lists.freedesktop.org \
--cc=iommu@lists.linux-foundation.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-arm-msm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=robdclark@chromium.org \
--cc=robdclark@gmail.com \
--cc=robin.murphy@arm.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).