Hi Will, On Thu, Jul 11, 2019 at 10:58 PM Will Deacon <w...@kernel.org> wrote: > > Hi everyone, > > This is a significant rework of the RFC I previously posted here: > > https://lkml.kernel.org/r/20190611134603.4253-1-will.dea...@arm.com > > But this time, it looks like it might actually be worthwhile according > to my perf profiles, where __iommu_unmap() falls a long way down the > profile for a multi-threaded netperf run. I'm still relying on others to > confirm this is useful, however. > > Some of the changes since last time are: > > * Support for constructing and submitting a list of commands in the > driver > > * Numerous changes to the IOMMU and io-pgtable APIs so that we can > submit commands in batches > > * Removal of cmpxchg() from cmdq_shared_lock() fast-path > > * Code restructuring and cleanups > > This current applies against my iommu/devel branch that Joerg has pulled > for 5.3. If you want to test it out, I've put everything here: > > > https://git.kernel.org/pub/scm/linux/kernel/git/will/linux.git/log/?h=iommu/cmdq > > Feedback welcome. I appreciate that we're in the merge window, but I > wanted to get this on the list for people to look at as an RFC.
I have tried branch iommu/cmdq on ThunderX2. I do see there is drastic reduction in CPU bandwidth consumption(from 15 to 20% to 1 to 2% in perf top) from SMMU CMDQ helper functions, when I run iperf with more than 64 clients(-P 64). However I have not noticed any measurable performance improvement in iperf results. IMO, this might/should help in performance improvement of IO intensive workloads. FWIW, you can add, Tested-by: Ganapatrao Kulkarni <gkulka...@marvell.com> > > Cheers, > > Will > > --->8 > > Cc: Jean-Philippe Brucker <jean-philippe.bruc...@arm.com> > Cc: Robin Murphy <robin.mur...@arm.com> > Cc: Jayachandran Chandrasekharan Nair <jn...@marvell.com> > Cc: Jan Glauber <jglau...@marvell.com> > Cc: Jon Masters <j...@redhat.com> > Cc: Eric Auger <eric.au...@redhat.com> > Cc: Zhen Lei <thunder.leiz...@huawei.com> > Cc: Jonathan Cameron <jonathan.came...@huawei.com> > Cc: Vijay Kilary <vkil...@codeaurora.org> > Cc: Joerg Roedel <j...@8bytes.org> > Cc: John Garry <john.ga...@huawei.com> > Cc: Alex Williamson <alex.william...@redhat.com> > > Will Deacon (19): > iommu: Remove empty iommu_tlb_range_add() callback from iommu_ops > iommu/io-pgtable-arm: Remove redundant call to io_pgtable_tlb_sync() > iommu/io-pgtable: Rename iommu_gather_ops to iommu_flush_ops > iommu: Introduce struct iommu_iotlb_gather for batching TLB flushes > iommu: Introduce iommu_iotlb_gather_add_page() > iommu: Pass struct iommu_iotlb_gather to ->unmap() and ->iotlb_sync() > iommu/io-pgtable: Introduce tlb_flush_walk() and tlb_flush_leaf() > iommu/io-pgtable: Hook up ->tlb_flush_walk() and ->tlb_flush_leaf() in > drivers > iommu/io-pgtable-arm: Call ->tlb_flush_walk() and ->tlb_flush_leaf() > iommu/io-pgtable: Replace ->tlb_add_flush() with ->tlb_add_page() > iommu/io-pgtable: Remove unused ->tlb_sync() callback > iommu/io-pgtable: Pass struct iommu_iotlb_gather to ->unmap() > iommu/io-pgtable: Pass struct iommu_iotlb_gather to ->tlb_add_page() > iommu/arm-smmu-v3: Separate s/w and h/w views of prod and cons indexes > iommu/arm-smmu-v3: Drop unused 'q' argument from Q_OVF macro > iommu/arm-smmu-v3: Move low-level queue fields out of arm_smmu_queue > iommu/arm-smmu-v3: Operate directly on low-level queue where possible > iommu/arm-smmu-v3: Reduce contention during command-queue insertion > iommu/arm-smmu-v3: Defer TLB invalidation until ->iotlb_sync() > > drivers/gpu/drm/panfrost/panfrost_mmu.c | 24 +- > drivers/iommu/amd_iommu.c | 11 +- > drivers/iommu/arm-smmu-v3.c | 856 > ++++++++++++++++++++++++-------- > drivers/iommu/arm-smmu.c | 103 +++- > drivers/iommu/dma-iommu.c | 9 +- > drivers/iommu/exynos-iommu.c | 3 +- > drivers/iommu/intel-iommu.c | 3 +- > drivers/iommu/io-pgtable-arm-v7s.c | 57 +-- > drivers/iommu/io-pgtable-arm.c | 48 +- > drivers/iommu/iommu.c | 24 +- > drivers/iommu/ipmmu-vmsa.c | 28 +- > drivers/iommu/msm_iommu.c | 42 +- > drivers/iommu/mtk_iommu.c | 45 +- > drivers/iommu/mtk_iommu_v1.c | 3 +- > drivers/iommu/omap-iommu.c | 2 +- > drivers/iommu/qcom_iommu.c | 44 +- > drivers/iommu/rockchip-iommu.c | 2 +- > drivers/iommu/s390-iommu.c | 3 +- > drivers/iommu/tegra-gart.c | 12 +- > drivers/iommu/tegra-smmu.c | 2 +- > drivers/vfio/vfio_iommu_type1.c | 27 +- > include/linux/io-pgtable.h | 57 ++- > include/linux/iommu.h | 92 +++- > 23 files changed, 1090 insertions(+), 407 deletions(-) > > -- > 2.11.0 > Thanks, Ganapat > _______________________________________________ > iommu mailing list > iommu@lists.linux-foundation.org > https://lists.linuxfoundation.org/mailman/listinfo/iommu _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
