Re: [PATCH v2 1/2] selftests: KVM: Move dirty logging functions to memstress.(c|h)

From: Vipin Sharma
Date: Mon Jan 23 2023 - 16:04:27 EST


On Mon, Jan 23, 2023 at 11:03 AM Ben Gardon <bgardon@xxxxxxxxxx> wrote:
>
> Move some helper functions from dirty_log_perf_test.c to the memstress
> library so that they can be used in a future commit which tests page
> splitting during dirty logging.
>
> Signed-off-by: Ben Gardon <bgardon@xxxxxxxxxx>
> ---
> .../selftests/kvm/dirty_log_perf_test.c | 84 ++-----------------
> .../testing/selftests/kvm/include/memstress.h | 8 ++
> tools/testing/selftests/kvm/lib/memstress.c | 72 ++++++++++++++++
> 3 files changed, 87 insertions(+), 77 deletions(-)
>
> diff --git a/tools/testing/selftests/kvm/dirty_log_perf_test.c b/tools/testing/selftests/kvm/dirty_log_perf_test.c
> index e9d6d1aecf89c..416719e205183 100644
> --- a/tools/testing/selftests/kvm/dirty_log_perf_test.c
> +++ b/tools/testing/selftests/kvm/dirty_log_perf_test.c
> @@ -136,77 +136,6 @@ struct test_params {
> bool random_access;
> };
>
> -static void toggle_dirty_logging(struct kvm_vm *vm, int slots, bool enable)
> -{
> - int i;
> -
> - for (i = 0; i < slots; i++) {
> - int slot = MEMSTRESS_MEM_SLOT_INDEX + i;
> - int flags = enable ? KVM_MEM_LOG_DIRTY_PAGES : 0;
> -
> - vm_mem_region_set_flags(vm, slot, flags);
> - }
> -}
> -
> -static inline void enable_dirty_logging(struct kvm_vm *vm, int slots)
> -{
> - toggle_dirty_logging(vm, slots, true);
> -}
> -
> -static inline void disable_dirty_logging(struct kvm_vm *vm, int slots)
> -{
> - toggle_dirty_logging(vm, slots, false);
> -}
> -
> -static void get_dirty_log(struct kvm_vm *vm, unsigned long *bitmaps[], int slots)
> -{
> - int i;
> -
> - for (i = 0; i < slots; i++) {
> - int slot = MEMSTRESS_MEM_SLOT_INDEX + i;
> -
> - kvm_vm_get_dirty_log(vm, slot, bitmaps[i]);
> - }
> -}
> -
> -static void clear_dirty_log(struct kvm_vm *vm, unsigned long *bitmaps[],
> - int slots, uint64_t pages_per_slot)
> -{
> - int i;
> -
> - for (i = 0; i < slots; i++) {
> - int slot = MEMSTRESS_MEM_SLOT_INDEX + i;
> -
> - kvm_vm_clear_dirty_log(vm, slot, bitmaps[i], 0, pages_per_slot);
> - }
> -}
> -
> -static unsigned long **alloc_bitmaps(int slots, uint64_t pages_per_slot)
> -{
> - unsigned long **bitmaps;
> - int i;
> -
> - bitmaps = malloc(slots * sizeof(bitmaps[0]));
> - TEST_ASSERT(bitmaps, "Failed to allocate bitmaps array.");
> -
> - for (i = 0; i < slots; i++) {
> - bitmaps[i] = bitmap_zalloc(pages_per_slot);
> - TEST_ASSERT(bitmaps[i], "Failed to allocate slot bitmap.");
> - }
> -
> - return bitmaps;
> -}
> -
> -static void free_bitmaps(unsigned long *bitmaps[], int slots)
> -{
> - int i;
> -
> - for (i = 0; i < slots; i++)
> - free(bitmaps[i]);
> -
> - free(bitmaps);
> -}
> -
> static void run_test(enum vm_guest_mode mode, void *arg)
> {
> struct test_params *p = arg;
> @@ -236,7 +165,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
> host_num_pages = vm_num_host_pages(mode, guest_num_pages);
> pages_per_slot = host_num_pages / p->slots;
>
> - bitmaps = alloc_bitmaps(p->slots, pages_per_slot);
> + bitmaps = memstress_alloc_bitmaps(p->slots, pages_per_slot);
>
> if (dirty_log_manual_caps)
> vm_enable_cap(vm, KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2,
> @@ -277,7 +206,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
>
> /* Enable dirty logging */
> clock_gettime(CLOCK_MONOTONIC, &start);
> - enable_dirty_logging(vm, p->slots);
> + memstress_enable_dirty_logging(vm, p->slots);
> ts_diff = timespec_elapsed(start);
> pr_info("Enabling dirty logging time: %ld.%.9lds\n\n",
> ts_diff.tv_sec, ts_diff.tv_nsec);
> @@ -306,7 +235,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
> iteration, ts_diff.tv_sec, ts_diff.tv_nsec);
>
> clock_gettime(CLOCK_MONOTONIC, &start);
> - get_dirty_log(vm, bitmaps, p->slots);
> + memstress_get_dirty_log(vm, bitmaps, p->slots);
> ts_diff = timespec_elapsed(start);
> get_dirty_log_total = timespec_add(get_dirty_log_total,
> ts_diff);
> @@ -315,7 +244,8 @@ static void run_test(enum vm_guest_mode mode, void *arg)
>
> if (dirty_log_manual_caps) {
> clock_gettime(CLOCK_MONOTONIC, &start);
> - clear_dirty_log(vm, bitmaps, p->slots, pages_per_slot);
> + memstress_clear_dirty_log(vm, bitmaps, p->slots,
> + pages_per_slot);
> ts_diff = timespec_elapsed(start);
> clear_dirty_log_total = timespec_add(clear_dirty_log_total,
> ts_diff);
> @@ -334,7 +264,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
>
> /* Disable dirty logging */
> clock_gettime(CLOCK_MONOTONIC, &start);
> - disable_dirty_logging(vm, p->slots);
> + memstress_disable_dirty_logging(vm, p->slots);
> ts_diff = timespec_elapsed(start);
> pr_info("Disabling dirty logging time: %ld.%.9lds\n",
> ts_diff.tv_sec, ts_diff.tv_nsec);
> @@ -359,7 +289,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
> clear_dirty_log_total.tv_nsec, avg.tv_sec, avg.tv_nsec);
> }
>
> - free_bitmaps(bitmaps, p->slots);
> + memstress_free_bitmaps(bitmaps, p->slots);
> arch_cleanup_vm(vm);
> memstress_destroy_vm(vm);
> }
> diff --git a/tools/testing/selftests/kvm/include/memstress.h b/tools/testing/selftests/kvm/include/memstress.h
> index 72e3e358ef7bd..ce4e603050eaa 100644
> --- a/tools/testing/selftests/kvm/include/memstress.h
> +++ b/tools/testing/selftests/kvm/include/memstress.h
> @@ -72,4 +72,12 @@ void memstress_guest_code(uint32_t vcpu_id);
> uint64_t memstress_nested_pages(int nr_vcpus);
> void memstress_setup_nested(struct kvm_vm *vm, int nr_vcpus, struct kvm_vcpu *vcpus[]);
>
> +void memstress_enable_dirty_logging(struct kvm_vm *vm, int slots);
> +void memstress_disable_dirty_logging(struct kvm_vm *vm, int slots);
> +void memstress_get_dirty_log(struct kvm_vm *vm, unsigned long *bitmaps[], int slots);
> +void memstress_clear_dirty_log(struct kvm_vm *vm, unsigned long *bitmaps[],
> + int slots, uint64_t pages_per_slot);
> +unsigned long **memstress_alloc_bitmaps(int slots, uint64_t pages_per_slot);
> +void memstress_free_bitmaps(unsigned long *bitmaps[], int slots);
> +
> #endif /* SELFTEST_KVM_MEMSTRESS_H */
> diff --git a/tools/testing/selftests/kvm/lib/memstress.c b/tools/testing/selftests/kvm/lib/memstress.c
> index 5f1d3173c238c..3632956c6bcf5 100644
> --- a/tools/testing/selftests/kvm/lib/memstress.c
> +++ b/tools/testing/selftests/kvm/lib/memstress.c
> @@ -5,6 +5,7 @@
> #define _GNU_SOURCE
>
> #include <inttypes.h>
> +#include <linux/bitmap.h>
>
> #include "kvm_util.h"
> #include "memstress.h"
> @@ -320,3 +321,74 @@ void memstress_join_vcpu_threads(int nr_vcpus)
> for (i = 0; i < nr_vcpus; i++)
> pthread_join(vcpu_threads[i].thread, NULL);
> }
> +
> +static void toggle_dirty_logging(struct kvm_vm *vm, int slots, bool enable)
> +{
> + int i;
> +
> + for (i = 0; i < slots; i++) {
> + int slot = MEMSTRESS_MEM_SLOT_INDEX + i;
> + int flags = enable ? KVM_MEM_LOG_DIRTY_PAGES : 0;
> +
> + vm_mem_region_set_flags(vm, slot, flags);
> + }
> +}
> +
> +void memstress_enable_dirty_logging(struct kvm_vm *vm, int slots)
> +{
> + toggle_dirty_logging(vm, slots, true);
> +}
> +
> +void memstress_disable_dirty_logging(struct kvm_vm *vm, int slots)
> +{
> + toggle_dirty_logging(vm, slots, false);
> +}

Very simple functions, maybe just make it inline in the memstress header.

> +
> +void memstress_get_dirty_log(struct kvm_vm *vm, unsigned long *bitmaps[], int slots)
> +{
> + int i;
> +
> + for (i = 0; i < slots; i++) {
> + int slot = MEMSTRESS_MEM_SLOT_INDEX + i;
> +
> + kvm_vm_get_dirty_log(vm, slot, bitmaps[i]);
> + }
> +}
> +
> +void memstress_clear_dirty_log(struct kvm_vm *vm, unsigned long *bitmaps[],
> + int slots, uint64_t pages_per_slot)
> +{
> + int i;
> +
> + for (i = 0; i < slots; i++) {
> + int slot = MEMSTRESS_MEM_SLOT_INDEX + i;
> +
> + kvm_vm_clear_dirty_log(vm, slot, bitmaps[i], 0, pages_per_slot);
> + }
> +}
> +
> +unsigned long **memstress_alloc_bitmaps(int slots, uint64_t pages_per_slot)
> +{
> + unsigned long **bitmaps;
> + int i;
> +
> + bitmaps = malloc(slots * sizeof(bitmaps[0]));
> + TEST_ASSERT(bitmaps, "Failed to allocate bitmaps array.");
> +
> + for (i = 0; i < slots; i++) {
> + bitmaps[i] = bitmap_zalloc(pages_per_slot);
> + TEST_ASSERT(bitmaps[i], "Failed to allocate slot bitmap.");
> + }
> +
> + return bitmaps;
> +}
> +
> +void memstress_free_bitmaps(unsigned long *bitmaps[], int slots)
> +{
> + int i;
> +
> + for (i = 0; i < slots; i++)
> + free(bitmaps[i]);
> +
> + free(bitmaps);
> +}
> --
> 2.39.1.405.gd4c25cc71f-goog
>

Other than the inline suggestion, which is optional.

Reviewed-by: Vipin Sharma <vipinsh@xxxxxxxxxx>