Message ID | 20210330080856.14940-1-wangyanan55@huawei.com (mailing list archive) |
---|---|
Headers | show |
Series | KVM: selftests: some improvement and a new test for kvm page table | expand |
Kindly ping... Hi Paolo, Will this series be picked up soon, or is there any other work for me to do? Regards, Yanan On 2021/3/30 16:08, Yanan Wang wrote: > Hi, > This v6 series can mainly include two parts. > Rebased on kvm queue branch: https://git.kernel.org/pub/scm/virt/kvm/kvm.git/log/?h=queue > > In the first part, all the known hugetlb backing src types specified > with different hugepage sizes are listed, so that we can specify use > of hugetlb source of the exact granularity that we want, instead of > the system default ones. And as all the known hugetlb page sizes are > listed, it's appropriate for all architectures. Besides, a helper that > can get granularity of different backing src types(anonumous/thp/hugetlb) > is added, so that we can use the accurate backing src granularity for > kinds of alignment or guest memory accessing of vcpus. > > In the second part, a new test is added: > This test is added to serve as a performance tester and a bug reproducer > for kvm page table code (GPA->HPA mappings), it gives guidance for the > people trying to make some improvement for kvm. And the following explains > what we can exactly do through this test. > > The function guest_code() can cover the conditions where a single vcpu or > multiple vcpus access guest pages within the same memory region, in three > VM stages(before dirty logging, during dirty logging, after dirty logging). > Besides, the backing src memory type(ANONYMOUS/THP/HUGETLB) of the tested > memory region can be specified by users, which means normal page mappings > or block mappings can be chosen by users to be created in the test. > > If ANONYMOUS memory is specified, kvm will create normal page mappings > for the tested memory region before dirty logging, and update attributes > of the page mappings from RO to RW during dirty logging. If THP/HUGETLB > memory is specified, kvm will create block mappings for the tested memory > region before dirty logging, and split the blcok mappings into normal page > mappings during dirty logging, and coalesce the page mappings back into > block mappings after dirty logging is stopped. > > So in summary, as a performance tester, this test can present the > performance of kvm creating/updating normal page mappings, or the > performance of kvm creating/splitting/recovering block mappings, > through execution time. > > When we need to coalesce the page mappings back to block mappings after > dirty logging is stopped, we have to firstly invalidate *all* the TLB > entries for the page mappings right before installation of the block entry, > because a TLB conflict abort error could occur if we can't invalidate the > TLB entries fully. We have hit this TLB conflict twice on aarch64 software > implementation and fixed it. As this test can imulate process from dirty > logging enabled to dirty logging stopped of a VM with block mappings, > so it can also reproduce this TLB conflict abort due to inadequate TLB > invalidation when coalescing tables. > > Links about the TLB conflict abort: > https://lore.kernel.org/lkml/20201201201034.116760-3-wangyanan55@huawei.com/ > > --- > > Change logs: > > v5->v6: > - Address Andrew Jones's comments for v5 series > - Add Andrew Jones's R-b tags in some patches > - Rebased on newest kvm/queue tree > - v5: https://lore.kernel.org/lkml/20210323135231.24948-1-wangyanan55@huawei.com/ > > v4->v5: > - Use synchronization(sem_wait) for time measurement > - Add a new patch about TEST_ASSERT(patch 4) > - Address Andrew Jones's comments for v4 series > - Add Andrew Jones's R-b tags in some patches > - v4: https://lore.kernel.org/lkml/20210302125751.19080-1-wangyanan55@huawei.com/ > > v3->v4: > - Add a helper to get system default hugetlb page size > - Add tags of Reviewed-by of Ben in the patches > - v3: https://lore.kernel.org/lkml/20210301065916.11484-1-wangyanan55@huawei.com/ > > v2->v3: > - Add tags of Suggested-by, Reviewed-by in the patches > - Add a generic micro to get hugetlb page sizes > - Some changes for suggestions about v2 series > - v2: https://lore.kernel.org/lkml/20210225055940.18748-1-wangyanan55@huawei.com/ > > v1->v2: > - Add a patch to sync header files > - Add helpers to get granularity of different backing src types > - Some changes for suggestions about v1 series > - v1: https://lore.kernel.org/lkml/20210208090841.333724-1-wangyanan55@huawei.com/ > > --- > > Yanan Wang (10): > tools headers: sync headers of asm-generic/hugetlb_encode.h > mm/hugetlb: Add a macro to get HUGETLB page sizes for mmap > KVM: selftests: Use flag CLOCK_MONOTONIC_RAW for timing > KVM: selftests: Print the errno besides error-string in TEST_ASSERT > KVM: selftests: Make a generic helper to get vm guest mode strings > KVM: selftests: Add a helper to get system configured THP page size > KVM: selftests: Add a helper to get system default hugetlb page size > KVM: selftests: List all hugetlb src types specified with page sizes > KVM: selftests: Adapt vm_userspace_mem_region_add to new helpers > KVM: selftests: Add a test for kvm page table code > > include/uapi/linux/mman.h | 2 + > tools/include/asm-generic/hugetlb_encode.h | 3 + > tools/include/uapi/linux/mman.h | 2 + > tools/testing/selftests/kvm/.gitignore | 1 + > tools/testing/selftests/kvm/Makefile | 3 + > .../selftests/kvm/demand_paging_test.c | 8 +- > .../selftests/kvm/dirty_log_perf_test.c | 14 +- > .../testing/selftests/kvm/include/kvm_util.h | 4 +- > .../testing/selftests/kvm/include/test_util.h | 21 +- > .../selftests/kvm/kvm_page_table_test.c | 506 ++++++++++++++++++ > tools/testing/selftests/kvm/lib/assert.c | 4 +- > tools/testing/selftests/kvm/lib/kvm_util.c | 59 +- > tools/testing/selftests/kvm/lib/test_util.c | 163 +++++- > tools/testing/selftests/kvm/steal_time.c | 4 +- > 14 files changed, 733 insertions(+), 61 deletions(-) > create mode 100644 tools/testing/selftests/kvm/kvm_page_table_test.c >
On 06/04/21 05:05, wangyanan (Y) wrote: > Kindly ping... > > Hi Paolo, > Will this series be picked up soon, or is there any other work for me to > do? > > Regards, > Yanan > > > On 2021/3/30 16:08, Yanan Wang wrote: >> Hi, >> This v6 series can mainly include two parts. >> Rebased on kvm queue branch: >> https://git.kernel.org/pub/scm/virt/kvm/kvm.git/log/?h=queue >> >> In the first part, all the known hugetlb backing src types specified >> with different hugepage sizes are listed, so that we can specify use >> of hugetlb source of the exact granularity that we want, instead of >> the system default ones. And as all the known hugetlb page sizes are >> listed, it's appropriate for all architectures. Besides, a helper that >> can get granularity of different backing src types(anonumous/thp/hugetlb) >> is added, so that we can use the accurate backing src granularity for >> kinds of alignment or guest memory accessing of vcpus. >> >> In the second part, a new test is added: >> This test is added to serve as a performance tester and a bug reproducer >> for kvm page table code (GPA->HPA mappings), it gives guidance for the >> people trying to make some improvement for kvm. And the following >> explains >> what we can exactly do through this test. >> >> The function guest_code() can cover the conditions where a single vcpu or >> multiple vcpus access guest pages within the same memory region, in three >> VM stages(before dirty logging, during dirty logging, after dirty >> logging). >> Besides, the backing src memory type(ANONYMOUS/THP/HUGETLB) of the tested >> memory region can be specified by users, which means normal page mappings >> or block mappings can be chosen by users to be created in the test. >> >> If ANONYMOUS memory is specified, kvm will create normal page mappings >> for the tested memory region before dirty logging, and update attributes >> of the page mappings from RO to RW during dirty logging. If THP/HUGETLB >> memory is specified, kvm will create block mappings for the tested memory >> region before dirty logging, and split the blcok mappings into normal >> page >> mappings during dirty logging, and coalesce the page mappings back into >> block mappings after dirty logging is stopped. >> >> So in summary, as a performance tester, this test can present the >> performance of kvm creating/updating normal page mappings, or the >> performance of kvm creating/splitting/recovering block mappings, >> through execution time. >> >> When we need to coalesce the page mappings back to block mappings after >> dirty logging is stopped, we have to firstly invalidate *all* the TLB >> entries for the page mappings right before installation of the block >> entry, >> because a TLB conflict abort error could occur if we can't invalidate the >> TLB entries fully. We have hit this TLB conflict twice on aarch64 >> software >> implementation and fixed it. As this test can imulate process from dirty >> logging enabled to dirty logging stopped of a VM with block mappings, >> so it can also reproduce this TLB conflict abort due to inadequate TLB >> invalidation when coalescing tables. >> >> Links about the TLB conflict abort: >> https://lore.kernel.org/lkml/20201201201034.116760-3-wangyanan55@huawei.com/ >> >> >> --- >> >> Change logs: >> >> v5->v6: >> - Address Andrew Jones's comments for v5 series >> - Add Andrew Jones's R-b tags in some patches >> - Rebased on newest kvm/queue tree >> - v5: >> https://lore.kernel.org/lkml/20210323135231.24948-1-wangyanan55@huawei.com/ >> >> >> v4->v5: >> - Use synchronization(sem_wait) for time measurement >> - Add a new patch about TEST_ASSERT(patch 4) >> - Address Andrew Jones's comments for v4 series >> - Add Andrew Jones's R-b tags in some patches >> - v4: >> https://lore.kernel.org/lkml/20210302125751.19080-1-wangyanan55@huawei.com/ >> >> >> v3->v4: >> - Add a helper to get system default hugetlb page size >> - Add tags of Reviewed-by of Ben in the patches >> - v3: >> https://lore.kernel.org/lkml/20210301065916.11484-1-wangyanan55@huawei.com/ >> >> >> v2->v3: >> - Add tags of Suggested-by, Reviewed-by in the patches >> - Add a generic micro to get hugetlb page sizes >> - Some changes for suggestions about v2 series >> - v2: >> https://lore.kernel.org/lkml/20210225055940.18748-1-wangyanan55@huawei.com/ >> >> >> v1->v2: >> - Add a patch to sync header files >> - Add helpers to get granularity of different backing src types >> - Some changes for suggestions about v1 series >> - v1: >> https://lore.kernel.org/lkml/20210208090841.333724-1-wangyanan55@huawei.com/ >> >> >> --- >> >> Yanan Wang (10): >> tools headers: sync headers of asm-generic/hugetlb_encode.h >> mm/hugetlb: Add a macro to get HUGETLB page sizes for mmap >> KVM: selftests: Use flag CLOCK_MONOTONIC_RAW for timing >> KVM: selftests: Print the errno besides error-string in TEST_ASSERT >> KVM: selftests: Make a generic helper to get vm guest mode strings >> KVM: selftests: Add a helper to get system configured THP page size >> KVM: selftests: Add a helper to get system default hugetlb page size >> KVM: selftests: List all hugetlb src types specified with page sizes >> KVM: selftests: Adapt vm_userspace_mem_region_add to new helpers >> KVM: selftests: Add a test for kvm page table code >> >> include/uapi/linux/mman.h | 2 + >> tools/include/asm-generic/hugetlb_encode.h | 3 + >> tools/include/uapi/linux/mman.h | 2 + >> tools/testing/selftests/kvm/.gitignore | 1 + >> tools/testing/selftests/kvm/Makefile | 3 + >> .../selftests/kvm/demand_paging_test.c | 8 +- >> .../selftests/kvm/dirty_log_perf_test.c | 14 +- >> .../testing/selftests/kvm/include/kvm_util.h | 4 +- >> .../testing/selftests/kvm/include/test_util.h | 21 +- >> .../selftests/kvm/kvm_page_table_test.c | 506 ++++++++++++++++++ >> tools/testing/selftests/kvm/lib/assert.c | 4 +- >> tools/testing/selftests/kvm/lib/kvm_util.c | 59 +- >> tools/testing/selftests/kvm/lib/test_util.c | 163 +++++- >> tools/testing/selftests/kvm/steal_time.c | 4 +- >> 14 files changed, 733 insertions(+), 61 deletions(-) >> create mode 100644 tools/testing/selftests/kvm/kvm_page_table_test.c >> > Queued, thanks. I moved MAP_HUGE_PAGE_SIZE from the uapi header to test_util.c, because I'm not confident in adding a new userspace API without an ack. Paolo