Add support to dirty-ring on dirty_log_perf_test, so we can measure performance differences when we change / improve the mechanism.
One major conflict I had in this set is that dirty-ring needs to be enabled after the VM was created, but before any cpu is created, so for that, I made a few changes on memstress so it can actually take dirty-ring size as a parameter for VM creation. (Patch #1) I honestly don't think it's pretty, but I could not think on a better way of doing this without messing too much in the code. Also added some checks in dirty-ring enable, so an error message on ring size is more informative. Please provide feedback :) Thanks! Leo Changes since RFCv1: - Stuff reported by Sashiko - Fixed elements / byte size wrapping issue - Removed element count due to concurrency - Testing exit_reason instead of ioctl return value - Some nits Link: https://lore.kernel.org/all/[email protected]/ Leonardo Bras (3): KVM: selftests: memstress: Add option to enable dirty-ring on VM creation KVM: selftests: Check dirty-ring size before enabling KVM: selftests: dirty_log_perf_test: Add dirty-ring support .../testing/selftests/kvm/include/memstress.h | 3 +- .../selftests/kvm/access_tracking_perf_test.c | 2 +- .../selftests/kvm/demand_paging_test.c | 2 +- .../selftests/kvm/dirty_log_perf_test.c | 95 +++++++++++++++++-- tools/testing/selftests/kvm/lib/kvm_util.c | 19 +++- tools/testing/selftests/kvm/lib/memstress.c | 34 ++++++- .../kvm/memslot_modification_stress_test.c | 2 +- .../kvm/x86/dirty_log_page_splitting_test.c | 2 +- 8 files changed, 137 insertions(+), 22 deletions(-) base-commit: dc59e4fea9d83f03bad6bddf3fa2e52491777482 -- 2.54.0
