Messages in this thread | | | From | Rob Clark <> | Date | Mon, 28 Oct 2019 15:38:04 -0700 | Subject | Re: [PATCH v2] iommu/arm-smmu: fix "hang" when games exit |
| |
On Mon, Oct 28, 2019 at 3:20 PM Will Deacon <will@kernel.org> wrote: > > 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.
yeah, not the best $subject, but I wasn't quite sure how to fit something better in a reasonable # of chars.. maybe something like: "iommu/arm-smmu: optimize unmap but avoiding toggling runpm state"?
BR, -R
> > > 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
| |