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auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=alex.williamson@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=63.128.21.124; envelope-from=alex.williamson@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/10/19 02:32:01 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: cohuck@redhat.com, cjia@nvidia.com, aik@ozlabs.ru, Zhengxiao.zx@Alibaba-inc.com, shuangtai.tst@alibaba-inc.com, qemu-devel@nongnu.org, peterx@redhat.com, eauger@redhat.com, yi.l.liu@intel.com, quintela@redhat.com, ziye.yang@intel.com, armbru@redhat.com, mlevitsk@redhat.com, pasic@linux.ibm.com, felipe@nutanix.com, zhi.a.wang@intel.com, kevin.tian@intel.com, yan.y.zhao@intel.com, dgilbert@redhat.com, changpeng.liu@intel.com, eskultet@redhat.com, Ken.Xue@amd.com, jonathan.davies@nutanix.com, pbonzini@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Mon, 19 Oct 2020 11:31:03 +0530 Kirti Wankhede wrote: > On 9/26/2020 3:53 AM, Alex Williamson wrote: > > On Wed, 23 Sep 2020 04:54:15 +0530 > > Kirti Wankhede wrote: > > > >> Create mapped iova list when vIOMMU is enabled. For each mapped iova > >> save translated address. Add node to list on MAP and remove node from > >> list on UNMAP. > >> This list is used to track dirty pages during migration. > >> > >> Signed-off-by: Kirti Wankhede > >> --- > >> hw/vfio/common.c | 58 ++++++++++++++++++++++++++++++++++++++----- > >> include/hw/vfio/vfio-common.h | 8 ++++++ > >> 2 files changed, 60 insertions(+), 6 deletions(-) > >> > >> diff --git a/hw/vfio/common.c b/hw/vfio/common.c > >> index d4959c036dd1..dc56cded2d95 100644 > >> --- a/hw/vfio/common.c > >> +++ b/hw/vfio/common.c > >> @@ -407,8 +407,8 @@ static bool vfio_listener_skipped_section(MemoryRegionSection *section) > >> } > >> > >> /* Called with rcu_read_lock held. */ > >> -static bool vfio_get_vaddr(IOMMUTLBEntry *iotlb, void **vaddr, > >> - bool *read_only) > >> +static bool vfio_get_xlat_addr(IOMMUTLBEntry *iotlb, void **vaddr, > >> + ram_addr_t *ram_addr, bool *read_only) > >> { > >> MemoryRegion *mr; > >> hwaddr xlat; > >> @@ -439,8 +439,17 @@ static bool vfio_get_vaddr(IOMMUTLBEntry *iotlb, void **vaddr, > >> return false; > >> } > >> > >> - *vaddr = memory_region_get_ram_ptr(mr) + xlat; > >> - *read_only = !writable || mr->readonly; > >> + if (vaddr) { > >> + *vaddr = memory_region_get_ram_ptr(mr) + xlat; > >> + } > >> + > >> + if (ram_addr) { > >> + *ram_addr = memory_region_get_ram_addr(mr) + xlat; > >> + } > >> + > >> + if (read_only) { > >> + *read_only = !writable || mr->readonly; > >> + } > >> > >> return true; > >> } > >> @@ -450,7 +459,6 @@ static void vfio_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb) > >> VFIOGuestIOMMU *giommu = container_of(n, VFIOGuestIOMMU, n); > >> VFIOContainer *container = giommu->container; > >> hwaddr iova = iotlb->iova + giommu->iommu_offset; > >> - bool read_only; > >> void *vaddr; > >> int ret; > >> > >> @@ -466,7 +474,10 @@ static void vfio_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb) > >> rcu_read_lock(); > >> > >> if ((iotlb->perm & IOMMU_RW) != IOMMU_NONE) { > >> - if (!vfio_get_vaddr(iotlb, &vaddr, &read_only)) { > >> + ram_addr_t ram_addr; > >> + bool read_only; > >> + > >> + if (!vfio_get_xlat_addr(iotlb, &vaddr, &ram_addr, &read_only)) { > >> goto out; > >> } > >> /* > >> @@ -484,8 +495,28 @@ static void vfio_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb) > >> "0x%"HWADDR_PRIx", %p) = %d (%m)", > >> container, iova, > >> iotlb->addr_mask + 1, vaddr, ret); > >> + } else { > >> + VFIOIovaRange *iova_range; > >> + > >> + iova_range = g_malloc0(sizeof(*iova_range)); > >> + iova_range->iova = iova; > >> + iova_range->size = iotlb->addr_mask + 1; > >> + iova_range->ram_addr = ram_addr; > >> + > >> + QLIST_INSERT_HEAD(&giommu->iova_list, iova_range, next); > >> } > >> } else { > >> + VFIOIovaRange *iova_range, *tmp; > >> + > >> + QLIST_FOREACH_SAFE(iova_range, &giommu->iova_list, next, tmp) { > >> + if (iova_range->iova >= iova && > >> + iova_range->iova + iova_range->size <= iova + > >> + iotlb->addr_mask + 1) { > >> + QLIST_REMOVE(iova_range, next); > >> + g_free(iova_range); > >> + } > >> + } > >> + > > > > > > This is some pretty serious overhead... can't we trigger a replay when > > migration is enabled to build this information then? > > Are you suggesting to call memory_region_iommu_replay() before > vfio_sync_dirty_bitmap(), which would call vfio_iommu_map_notify() where > iova list of mapping is maintained? Then in the notifer check if > migration_is_running() and container->dirty_pages_supported == true, > then only create iova mapping tree? In this case how would we know that > this is triggered by > vfio_sync_dirty_bitmap() > -> memory_region_iommu_replay() > and we don't have to call vfio_dma_map()? memory_region_iommu_replay() calls a notifier of our choice, so we could create a notifier specifically for creating this tree when dirty logging is enabled. Thanks, Alex > > We're looking at > > potentially thousands of entries, so a list is probably also not a good > > choice. > > Changing it to tree. > > Thanks, > Kirti > > I don't think it's acceptable to incur this even when not > > migrating (ie. the vast majority of the time). Thanks, > > > > Alex > > > >> ret = vfio_dma_unmap(container, iova, iotlb->addr_mask + 1); > >> if (ret) { > >> error_report("vfio_dma_unmap(%p, 0x%"HWADDR_PRIx", " > >> @@ -642,6 +673,7 @@ static void vfio_listener_region_add(MemoryListener *listener, > >> g_free(giommu); > >> goto fail; > >> } > >> + QLIST_INIT(&giommu->iova_list); > >> QLIST_INSERT_HEAD(&container->giommu_list, giommu, giommu_next); > >> memory_region_iommu_replay(giommu->iommu, &giommu->n); > >> > >> @@ -740,6 +772,13 @@ static void vfio_listener_region_del(MemoryListener *listener, > >> QLIST_FOREACH(giommu, &container->giommu_list, giommu_next) { > >> if (MEMORY_REGION(giommu->iommu) == section->mr && > >> giommu->n.start == section->offset_within_region) { > >> + VFIOIovaRange *iova_range, *tmp; > >> + > >> + QLIST_FOREACH_SAFE(iova_range, &giommu->iova_list, next, tmp) { > >> + QLIST_REMOVE(iova_range, next); > >> + g_free(iova_range); > >> + } > >> + > >> memory_region_unregister_iommu_notifier(section->mr, > >> &giommu->n); > >> QLIST_REMOVE(giommu, giommu_next); > >> @@ -1541,6 +1580,13 @@ static void vfio_disconnect_container(VFIOGroup *group) > >> QLIST_REMOVE(container, next); > >> > >> QLIST_FOREACH_SAFE(giommu, &container->giommu_list, giommu_next, tmp) { > >> + VFIOIovaRange *iova_range, *itmp; > >> + > >> + QLIST_FOREACH_SAFE(iova_range, &giommu->iova_list, next, itmp) { > >> + QLIST_REMOVE(iova_range, next); > >> + g_free(iova_range); > >> + } > >> + > >> memory_region_unregister_iommu_notifier( > >> MEMORY_REGION(giommu->iommu), &giommu->n); > >> QLIST_REMOVE(giommu, giommu_next); > >> diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h > >> index 0a1651eda2d0..aa7524fe2cc5 100644 > >> --- a/include/hw/vfio/vfio-common.h > >> +++ b/include/hw/vfio/vfio-common.h > >> @@ -89,11 +89,19 @@ typedef struct VFIOContainer { > >> QLIST_ENTRY(VFIOContainer) next; > >> } VFIOContainer; > >> > >> +typedef struct VFIOIovaRange { > >> + hwaddr iova; > >> + size_t size; > >> + ram_addr_t ram_addr; > >> + QLIST_ENTRY(VFIOIovaRange) next; > >> +} VFIOIovaRange; > >> + > >> typedef struct VFIOGuestIOMMU { > >> VFIOContainer *container; > >> IOMMUMemoryRegion *iommu; > >> hwaddr iommu_offset; > >> IOMMUNotifier n; > >> + QLIST_HEAD(, VFIOIovaRange) iova_list; > >> QLIST_ENTRY(VFIOGuestIOMMU) giommu_next; > >> } VFIOGuestIOMMU; > >> > > >