From 1eafbd27edb5098ed6b6bc404c35d56c78beb0fd Mon Sep 17 00:00:00 2001 From: Ben Gardon Date: Tue, 27 Oct 2020 16:37:31 -0700 Subject: KVM: selftests: Simplify demand_paging_test with timespec_diff_now Add a helper function to get the current time and return the time since a given start time. Use that function to simplify the timekeeping in the demand paging test. This series was tested by running the following invocations on an Intel Skylake machine: dirty_log_perf_test -b 20m -i 100 -v 64 dirty_log_perf_test -b 20g -i 5 -v 4 dirty_log_perf_test -b 4g -i 5 -v 32 demand_paging_test -b 20m -v 64 demand_paging_test -b 20g -v 4 demand_paging_test -b 4g -v 32 All behaved as expected. Signed-off-by: Ben Gardon Message-Id: <20201027233733.1484855-4-bgardon@google.com> Signed-off-by: Paolo Bonzini --- tools/testing/selftests/kvm/lib/test_util.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) (limited to 'tools/testing/selftests/kvm/lib/test_util.c') diff --git a/tools/testing/selftests/kvm/lib/test_util.c b/tools/testing/selftests/kvm/lib/test_util.c index 689e97c27ee2..1a46c2c48c7c 100644 --- a/tools/testing/selftests/kvm/lib/test_util.c +++ b/tools/testing/selftests/kvm/lib/test_util.c @@ -4,10 +4,13 @@ * * Copyright (C) 2020, Google LLC. */ -#include + +#include #include #include -#include +#include +#include + #include "test_util.h" /* @@ -81,6 +84,14 @@ struct timespec timespec_sub(struct timespec ts1, struct timespec ts2) return timespec_add_ns((struct timespec){0}, ns1 - ns2); } +struct timespec timespec_diff_now(struct timespec start) +{ + struct timespec end; + + clock_gettime(CLOCK_MONOTONIC, &end); + return timespec_sub(end, start); +} + void print_skip(const char *fmt, ...) { va_list ap; -- cgit From 4fd94ec7d566ee2f0b52111cc6d26dd311f8a7c3 Mon Sep 17 00:00:00 2001 From: Ben Gardon Date: Tue, 27 Oct 2020 16:37:33 -0700 Subject: KVM: selftests: Introduce the dirty log perf test The dirty log perf test will time verious dirty logging operations (enabling dirty logging, dirtying memory, getting the dirty log, clearing the dirty log, and disabling dirty logging) in order to quantify dirty logging performance. This test can be used to inform future performance improvements to KVM's dirty logging infrastructure. This series was tested by running the following invocations on an Intel Skylake machine: dirty_log_perf_test -b 20m -i 100 -v 64 dirty_log_perf_test -b 20g -i 5 -v 4 dirty_log_perf_test -b 4g -i 5 -v 32 demand_paging_test -b 20m -v 64 demand_paging_test -b 20g -v 4 demand_paging_test -b 4g -v 32 All behaved as expected. Signed-off-by: Ben Gardon Message-Id: <20201027233733.1484855-6-bgardon@google.com> Signed-off-by: Paolo Bonzini --- tools/testing/selftests/kvm/lib/test_util.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'tools/testing/selftests/kvm/lib/test_util.c') diff --git a/tools/testing/selftests/kvm/lib/test_util.c b/tools/testing/selftests/kvm/lib/test_util.c index 1a46c2c48c7c..8e04c0b1608e 100644 --- a/tools/testing/selftests/kvm/lib/test_util.c +++ b/tools/testing/selftests/kvm/lib/test_util.c @@ -92,6 +92,13 @@ struct timespec timespec_diff_now(struct timespec start) return timespec_sub(end, start); } +struct timespec timespec_div(struct timespec ts, int divisor) +{ + int64_t ns = timespec_to_ns(ts) / divisor; + + return timespec_add_ns((struct timespec){0}, ns); +} + void print_skip(const char *fmt, ...) { va_list ap; -- cgit