search for: arm_smmu_tlb_inv_range_nosync

...e. > > About SMMUv3 issues I already reported one big limitation with respect > to hugepage invalidation. See [RFC v2 4/4] iommu/arm-smmu-v3: add > CMD_TLBI_NH_VA_AM command for iova range invalidation > (https://lkml.org/lkml/2017/8/11/428). > > At smmuv3 guest driver level, arm_smmu_tlb_inv_range_nosync(), when > called with a hugepage size, invalidates each 4K/64K page of the region > and not the whole region at once. Each of them are trapped by the SMMUv3 > device which forwards them to the host. This stalls the guest. This > issue can be observed in DPDK case - not the use case benc...

...ch may mostly explain the difference. About SMMUv3 issues I already reported one big limitation with respect to hugepage invalidation. See [RFC v2 4/4] iommu/arm-smmu-v3: add CMD_TLBI_NH_VA_AM command for iova range invalidation (https://lkml.org/lkml/2017/8/11/428). At smmuv3 guest driver level, arm_smmu_tlb_inv_range_nosync(), when called with a hugepage size, invalidates each 4K/64K page of the region and not the whole region at once. Each of them are trapped by the SMMUv3 device which forwards them to the host. This stalls the guest. This issue can be observed in DPDK case - not the use case benchmarked above - . I...

On Fri, Dec 07, 2018 at 06:52:31PM +0000, Jean-Philippe Brucker wrote: > Sorry for the delay, I wanted to do a little more performance analysis > before continuing. > > On 27/11/2018 18:10, Michael S. Tsirkin wrote: > > On Tue, Nov 27, 2018 at 05:55:20PM +0000, Jean-Philippe Brucker wrote: > >>>> + if (!virtio_has_feature(vdev, VIRTIO_F_VERSION_1) || >