On 23/01/2020 19.04, Ben Gardon wrote: > While userfaultfd, KVM's demand paging implementation, is not specific > to KVM, having a benchmark for its performance will be useful for > guiding performance improvements to KVM. As a first step towards creating > a userfaultfd demand paging test, create a simple memory access test, > based on dirty_log_test. > > Reviewed-by: Oliver Upton <oupton@xxxxxxxxxx> > Signed-off-by: Ben Gardon <bgardon@xxxxxxxxxx> > --- > tools/testing/selftests/kvm/.gitignore | 1 + > tools/testing/selftests/kvm/Makefile | 3 + > .../selftests/kvm/demand_paging_test.c | 286 ++++++++++++++++++ > 3 files changed, 290 insertions(+) > create mode 100644 tools/testing/selftests/kvm/demand_paging_test.c > > diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore > index 30072c3f52fbe..9619d96e15c41 100644 > --- a/tools/testing/selftests/kvm/.gitignore > +++ b/tools/testing/selftests/kvm/.gitignore > @@ -17,3 +17,4 @@ > /clear_dirty_log_test > /dirty_log_test > /kvm_create_max_vcpus > +/demand_paging_test > diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile > index 3138a916574a9..e2e1b92faee3b 100644 > --- a/tools/testing/selftests/kvm/Makefile > +++ b/tools/testing/selftests/kvm/Makefile > @@ -28,15 +28,18 @@ TEST_GEN_PROGS_x86_64 += x86_64/vmx_tsc_adjust_test > TEST_GEN_PROGS_x86_64 += x86_64/xss_msr_test > TEST_GEN_PROGS_x86_64 += clear_dirty_log_test > TEST_GEN_PROGS_x86_64 += dirty_log_test > +TEST_GEN_PROGS_x86_64 += demand_paging_test > TEST_GEN_PROGS_x86_64 += kvm_create_max_vcpus > > TEST_GEN_PROGS_aarch64 += clear_dirty_log_test > TEST_GEN_PROGS_aarch64 += dirty_log_test > +TEST_GEN_PROGS_aarch64 += demand_paging_test > TEST_GEN_PROGS_aarch64 += kvm_create_max_vcpus > > TEST_GEN_PROGS_s390x = s390x/memop > TEST_GEN_PROGS_s390x += s390x/sync_regs_test > TEST_GEN_PROGS_s390x += dirty_log_test > +TEST_GEN_PROGS_s390x += demand_paging_test > TEST_GEN_PROGS_s390x += kvm_create_max_vcpus I gave your series a quick try on s390x (without patch 10/10 since that is causing more trouble), but the test does not work there yet: # selftests: kvm: demand_paging_test # ==== Test Assertion Failure ==== # lib/kvm_util.c:700: ret == 0 # pid=247240 tid=247240 - Invalid argument # 1 0x0000000001004085: vm_userspace_mem_region_add at kvm_util.c:695 # 2 0x00000000010042dd: _vm_create at kvm_util.c:233 # 3 0x0000000001001b07: create_vm at demand_paging_test.c:185 # 4 (inlined by) run_test at demand_paging_test.c:387 # 5 (inlined by) main at demand_paging_test.c:676 # 6 0x000003ffb5323461: ?? ??:0 # 7 0x000000000100259d: .annobin_init.c.hot at crt1.o:? # 8 0xffffffffffffffff: ?? ??:0 # KVM_SET_USER_MEMORY_REGION IOCTL failed, # rc: -1 errno: 22 # slot: 0 flags: 0x0 # guest_phys_addr: 0x0 size: 0x607000 # Testing guest mode: PA-bits:40, VA-bits:48, 4K pages not ok 4 selftests: kvm: demand_paging_test # exit=254 I'd suggest to leave it disabled on s390x until the issue has been debugged. Thomas
