2023-04-21 16:55:12

by Vipin Sharma

[permalink] [raw]
Subject: [PATCH 2/9] KVM: selftests: Add optional delay between consecutive Clear-Dirty-Log calls

In dirty_log_perf_test, add option "-l" to wait between consecutive
Clear-Dirty-Log calls. Accept delay in milliseconds.

This allows dirty_log_perf_test to mimic real world use where after
clearing dirty memory, some time is spent in transferring memory before
making a subsequeunt Clear-Dirty-Log call.

Signed-off-by: Vipin Sharma <[email protected]>
---
.../testing/selftests/kvm/dirty_log_perf_test.c | 17 +++++++++++++++--
tools/testing/selftests/kvm/include/memstress.h | 5 +++--
tools/testing/selftests/kvm/lib/memstress.c | 10 +++++++++-
3 files changed, 27 insertions(+), 5 deletions(-)

diff --git a/tools/testing/selftests/kvm/dirty_log_perf_test.c b/tools/testing/selftests/kvm/dirty_log_perf_test.c
index 0852a7ba42e1..338f03a4a550 100644
--- a/tools/testing/selftests/kvm/dirty_log_perf_test.c
+++ b/tools/testing/selftests/kvm/dirty_log_perf_test.c
@@ -135,6 +135,7 @@ struct test_params {
uint32_t random_seed;
bool random_access;
uint64_t clear_chunk_size;
+ int clear_chunk_wait_time_ms
};

static void run_test(enum vm_guest_mode mode, void *arg)
@@ -249,7 +250,8 @@ static void run_test(enum vm_guest_mode mode, void *arg)
clock_gettime(CLOCK_MONOTONIC, &start);
memstress_clear_dirty_log_in_chunks(vm, bitmaps, p->slots,
pages_per_slot,
- pages_per_clear);
+ pages_per_clear,
+ p->clear_chunk_wait_time_ms);
ts_diff = timespec_elapsed(start);
clear_dirty_log_total = timespec_add(clear_dirty_log_total,
ts_diff);
@@ -352,6 +354,11 @@ static void help(char *name)
" the memslot size then whole memslot is cleared in one call.\n"
" Size must be aligned to the host page size. e.g. 10M or 3G\n"
" (default: UINT64_MAX, clears whole memslot in one call)\n");
+ printf(" -l: Specify time in milliseconds to wait after Clear-Dirty-Log\n"
+ " call. This allows to mimic use cases where flow is to get\n"
+ " dirty log followed by multiple clear dirty log calls and\n"
+ " sending corresponding memory to destination (in this test\n"
+ " sending will be just idle waiting)\n");
puts("");
exit(0);
}
@@ -368,6 +375,7 @@ int main(int argc, char *argv[])
.random_seed = 1,
.write_percent = 100,
.clear_chunk_size = UINT64_MAX,
+ .clear_chunk_wait_time_ms = 0,
};
int opt;

@@ -378,7 +386,7 @@ int main(int argc, char *argv[])

guest_modes_append_default();

- while ((opt = getopt(argc, argv, "ab:c:eghi:k:m:nop:r:s:v:x:w:")) != -1) {
+ while ((opt = getopt(argc, argv, "ab:c:eghi:k:l:m:nop:r:s:v:x:w:")) != -1) {
switch (opt) {
case 'a':
p.random_access = true;
@@ -405,6 +413,11 @@ int main(int argc, char *argv[])
case 'k':
p.clear_chunk_size = parse_size(optarg);
break;
+ case 'l':
+ p.clear_chunk_wait_time_ms =
+ atoi_non_negative("Clear dirty log chunks wait time",
+ optarg);
+ break;
case 'm':
guest_modes_cmdline(optarg);
break;
diff --git a/tools/testing/selftests/kvm/include/memstress.h b/tools/testing/selftests/kvm/include/memstress.h
index 2acc93f76fc3..01fdcea80360 100644
--- a/tools/testing/selftests/kvm/include/memstress.h
+++ b/tools/testing/selftests/kvm/include/memstress.h
@@ -78,12 +78,13 @@ void memstress_get_dirty_log(struct kvm_vm *vm, unsigned long *bitmaps[], int sl
void memstress_clear_dirty_log_in_chunks(struct kvm_vm *vm,
unsigned long *bitmaps[], int slots,
uint64_t pages_per_slot,
- uint64_t pages_per_clear);
+ uint64_t pages_per_clear,
+ int wait_ms);
static inline void memstress_clear_dirty_log(struct kvm_vm *vm,
unsigned long *bitmaps[], int slots,
uint64_t pages_per_slot) {
memstress_clear_dirty_log_in_chunks(vm, bitmaps, slots, pages_per_slot,
- pages_per_slot);
+ pages_per_slot, 0);
}
unsigned long **memstress_alloc_bitmaps(int slots, uint64_t pages_per_slot);
void memstress_free_bitmaps(unsigned long *bitmaps[], int slots);
diff --git a/tools/testing/selftests/kvm/lib/memstress.c b/tools/testing/selftests/kvm/lib/memstress.c
index e0c701ab4e9a..483ecbc53a5b 100644
--- a/tools/testing/selftests/kvm/lib/memstress.c
+++ b/tools/testing/selftests/kvm/lib/memstress.c
@@ -358,10 +358,15 @@ void memstress_get_dirty_log(struct kvm_vm *vm, unsigned long *bitmaps[], int sl
void memstress_clear_dirty_log_in_chunks(struct kvm_vm *vm,
unsigned long *bitmaps[], int slots,
uint64_t pages_per_slot,
- uint64_t pages_per_clear)
+ uint64_t pages_per_clear,
+ int wait_ms)
{
int i, slot;
uint64_t from, clear_pages_count;
+ struct timespec wait = {
+ .tv_sec = wait_ms / 1000,
+ .tv_nsec = (wait_ms % 1000) * 1000000ull,
+ };

for (i = 0; i < slots; i++) {
slot = MEMSTRESS_MEM_SLOT_INDEX + i;
@@ -374,6 +379,9 @@ void memstress_clear_dirty_log_in_chunks(struct kvm_vm *vm,
kvm_vm_clear_dirty_log(vm, slot, bitmaps[i], from,
clear_pages_count);
from += clear_pages_count;
+ if (wait_ms)
+ nanosleep(&wait, NULL);
+
}
}

--
2.40.0.634.g4ca3ef3211-goog