Messages in this thread | | | Date | Mon, 28 Oct 2019 22:20:42 +0000 | From | Will Deacon <> | Subject | Re: [PATCH v2] iommu/arm-smmu: fix "hang" when games exit |
| |
Hi Rob,
On Mon, Oct 07, 2019 at 01:49:06PM -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.
Please can you reword the subject to be a bit more useful? The commit message is great, but the subject is a bit like "fix bug in code" to me.
> Signed-off-by: Rob Clark <robdclark@chromium.org> > --- > v1: original > v2: unconditionally use autosuspend, rather than deciding based on what > consumer does > > drivers/iommu/arm-smmu.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c > index 3f1d55fb43c4..b7b41f5001bc 100644 > --- a/drivers/iommu/arm-smmu.c > +++ b/drivers/iommu/arm-smmu.c > @@ -289,7 +289,7 @@ 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) > @@ -1445,6 +1445,9 @@ 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);
Please can you put a comment here explaining what this is doing? An abridged version of the commit message is fine.
> + pm_runtime_set_autosuspend_delay(smmu->dev, 20); > + pm_runtime_use_autosuspend(smmu->dev);
Cheers,
Will
| |