| Message ID | 20220817214146.3285106-4-coltonlewis@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Randomize memory access of dirty_log_perf_test | expand |
On Wed, Aug 17, 2022 at 09:41:46PM +0000, Colton Lewis wrote: > diff --git a/tools/testing/selftests/kvm/dirty_log_perf_test.c b/tools/testing/selftests/kvm/dirty_log_perf_test.c > index 9226eeea79bc..af9754bda0a4 100644 > --- a/tools/testing/selftests/kvm/dirty_log_perf_test.c > +++ b/tools/testing/selftests/kvm/dirty_log_perf_test.c > while ((opt = getopt(argc, argv, "eghi:p:m:nb:v:or:s:x:w:")) != -1) { > switch (opt) { > + case 'a': > + p.random_access = true; > + break; > case 'e': > /* 'e' is for evil. */ > run_vcpus_while_disabling_dirty_logging = true; Was double checking this and forgot to add an "a" to the getopt string. This is small enough that I will wait for the rest to get more eyes before rerolling the patch.
On Wed, Aug 17, 2022 at 09:41:46PM +0000, Colton Lewis wrote: > Create the ability to randomize page access order with the -a > argument, including the possibility that the same pages may be hit > multiple times during an iteration or not at all. > > Signed-off-by: Colton Lewis <coltonlewis@google.com> > --- > tools/testing/selftests/kvm/dirty_log_perf_test.c | 10 +++++++++- > .../testing/selftests/kvm/include/perf_test_util.h | 2 ++ > tools/testing/selftests/kvm/lib/perf_test_util.c | 13 ++++++++++++- > 3 files changed, 23 insertions(+), 2 deletions(-) > > diff --git a/tools/testing/selftests/kvm/dirty_log_perf_test.c b/tools/testing/selftests/kvm/dirty_log_perf_test.c > index 9226eeea79bc..af9754bda0a4 100644 > --- a/tools/testing/selftests/kvm/dirty_log_perf_test.c > +++ b/tools/testing/selftests/kvm/dirty_log_perf_test.c > @@ -133,6 +133,7 @@ struct test_params { > int slots; > uint32_t write_percent; > uint32_t random_seed; > + bool random_access; > }; > > static void toggle_dirty_logging(struct kvm_vm *vm, int slots, bool enable) > @@ -271,6 +272,9 @@ static void run_test(enum vm_guest_mode mode, void *arg) > pr_info("Enabling dirty logging time: %ld.%.9lds\n\n", > ts_diff.tv_sec, ts_diff.tv_nsec); > > + /* Set random access here, after population phase. */ > + perf_test_set_random_access(vm, p->random_access); Optional suggestion: We don't have any use-case for disabling random access, so perhaps this would be simpler as: if (p->random_access) perf_test_enable_random_access(vm); And then: void perf_test_enable_random_access(struct kvm_vm *vm) { perf_test_args.random_access = true; sync_global_to_guest(vm, perf_test_args); } > + > while (iteration < p->iterations) { > /* > * Incrementing the iteration number will start the vCPUs > @@ -353,10 +357,11 @@ static void run_test(enum vm_guest_mode mode, void *arg) > static void help(char *name) > { > puts(""); > - printf("usage: %s [-h] [-i iterations] [-p offset] [-g] " > + printf("usage: %s [-h] [-a] [-i iterations] [-p offset] [-g] " > "[-m mode] [-n] [-b vcpu bytes] [-v vcpus] [-o] [-r random seed ] [-s mem type]" > "[-x memslots] [-w percentage]\n", name); > puts(""); > + printf(" -a: access memory randomly rather than in order.\n"); > printf(" -i: specify iteration counts (default: %"PRIu64")\n", > TEST_HOST_LOOP_N); > printf(" -g: Do not enable KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2. This\n" > @@ -413,6 +418,9 @@ int main(int argc, char *argv[]) > > while ((opt = getopt(argc, argv, "eghi:p:m:nb:v:or:s:x:w:")) != -1) { > switch (opt) { > + case 'a': > + p.random_access = true; > + break; > case 'e': > /* 'e' is for evil. */ > run_vcpus_while_disabling_dirty_logging = true; > diff --git a/tools/testing/selftests/kvm/include/perf_test_util.h b/tools/testing/selftests/kvm/include/perf_test_util.h > index 8da4a839c585..237899f3f4fe 100644 > --- a/tools/testing/selftests/kvm/include/perf_test_util.h > +++ b/tools/testing/selftests/kvm/include/perf_test_util.h > @@ -41,6 +41,7 @@ struct perf_test_args { > > /* Run vCPUs in L2 instead of L1, if the architecture supports it. */ > bool nested; > + bool random_access; > > struct perf_test_vcpu_args vcpu_args[KVM_MAX_VCPUS]; > }; > @@ -55,6 +56,7 @@ void perf_test_destroy_vm(struct kvm_vm *vm); > > void perf_test_set_write_percent(struct kvm_vm *vm, uint32_t write_percent); > void perf_test_set_random_seed(struct kvm_vm *vm, uint32_t random_seed); > +void perf_test_set_random_access(struct kvm_vm *vm, bool random_access); > > void perf_test_start_vcpu_threads(int vcpus, void (*vcpu_fn)(struct perf_test_vcpu_args *)); > void perf_test_join_vcpu_threads(int vcpus); > diff --git a/tools/testing/selftests/kvm/lib/perf_test_util.c b/tools/testing/selftests/kvm/lib/perf_test_util.c > index 1a6b69713337..84e442a028c0 100644 > --- a/tools/testing/selftests/kvm/lib/perf_test_util.c > +++ b/tools/testing/selftests/kvm/lib/perf_test_util.c > @@ -48,6 +48,7 @@ void perf_test_guest_code(uint32_t vcpu_idx) > struct perf_test_vcpu_args *vcpu_args = &pta->vcpu_args[vcpu_idx]; > uint64_t gva; > uint64_t pages; > + uint64_t addr; > uint32_t *rnd_arr = (uint32_t *)vcpu_args->random_array; > int i; > > @@ -59,7 +60,11 @@ void perf_test_guest_code(uint32_t vcpu_idx) > > while (true) { > for (i = 0; i < pages; i++) { > - uint64_t addr = gva + (i * pta->guest_page_size); > + if (pta->random_access) > + addr = gva + > + ((rnd_arr[i] % pages) * pta->guest_page_size); > + else > + addr = gva + (i * pta->guest_page_size); > > if (rnd_arr[i] % 100 < pta->write_percent) > *(uint64_t *)addr = 0x0123456789ABCDEF; > @@ -271,6 +276,12 @@ void perf_test_set_random_seed(struct kvm_vm *vm, uint32_t random_seed) > sync_global_to_guest(vm, perf_test_args); > } > > +void perf_test_set_random_access(struct kvm_vm *vm, bool random_access) > +{ > + perf_test_args.random_access = random_access; > + sync_global_to_guest(vm, perf_test_args); > +} > + > uint64_t __weak perf_test_nested_pages(int nr_vcpus) > { > return 0; > -- > 2.37.1.595.g718a3a8f04-goog >
Hey Colton, On Wed, Aug 17, 2022 at 09:41:46PM +0000, Colton Lewis wrote: > Create the ability to randomize page access order with the -a > argument, including the possibility that the same pages may be hit > multiple times during an iteration or not at all. > > Signed-off-by: Colton Lewis <coltonlewis@google.com> > --- > tools/testing/selftests/kvm/dirty_log_perf_test.c | 10 +++++++++- > .../testing/selftests/kvm/include/perf_test_util.h | 2 ++ > tools/testing/selftests/kvm/lib/perf_test_util.c | 13 ++++++++++++- > 3 files changed, 23 insertions(+), 2 deletions(-) > > diff --git a/tools/testing/selftests/kvm/dirty_log_perf_test.c b/tools/testing/selftests/kvm/dirty_log_perf_test.c > index 9226eeea79bc..af9754bda0a4 100644 > --- a/tools/testing/selftests/kvm/dirty_log_perf_test.c > +++ b/tools/testing/selftests/kvm/dirty_log_perf_test.c > @@ -133,6 +133,7 @@ struct test_params { > int slots; > uint32_t write_percent; > uint32_t random_seed; > + bool random_access; > }; > > static void toggle_dirty_logging(struct kvm_vm *vm, int slots, bool enable) > @@ -271,6 +272,9 @@ static void run_test(enum vm_guest_mode mode, void *arg) > pr_info("Enabling dirty logging time: %ld.%.9lds\n\n", > ts_diff.tv_sec, ts_diff.tv_nsec); > > + /* Set random access here, after population phase. */ > + perf_test_set_random_access(vm, p->random_access); > + > while (iteration < p->iterations) { > /* > * Incrementing the iteration number will start the vCPUs > @@ -353,10 +357,11 @@ static void run_test(enum vm_guest_mode mode, void *arg) > static void help(char *name) > { > puts(""); > - printf("usage: %s [-h] [-i iterations] [-p offset] [-g] " > + printf("usage: %s [-h] [-a] [-i iterations] [-p offset] [-g] " > "[-m mode] [-n] [-b vcpu bytes] [-v vcpus] [-o] [-r random seed ] [-s mem type]" > "[-x memslots] [-w percentage]\n", name); > puts(""); > + printf(" -a: access memory randomly rather than in order.\n"); > printf(" -i: specify iteration counts (default: %"PRIu64")\n", > TEST_HOST_LOOP_N); > printf(" -g: Do not enable KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2. This\n" > @@ -413,6 +418,9 @@ int main(int argc, char *argv[]) > > while ((opt = getopt(argc, argv, "eghi:p:m:nb:v:or:s:x:w:")) != -1) { > switch (opt) { > + case 'a': > + p.random_access = true; > + break; > case 'e': > /* 'e' is for evil. */ > run_vcpus_while_disabling_dirty_logging = true; > diff --git a/tools/testing/selftests/kvm/include/perf_test_util.h b/tools/testing/selftests/kvm/include/perf_test_util.h > index 8da4a839c585..237899f3f4fe 100644 > --- a/tools/testing/selftests/kvm/include/perf_test_util.h > +++ b/tools/testing/selftests/kvm/include/perf_test_util.h > @@ -41,6 +41,7 @@ struct perf_test_args { > > /* Run vCPUs in L2 instead of L1, if the architecture supports it. */ > bool nested; > + bool random_access; > > struct perf_test_vcpu_args vcpu_args[KVM_MAX_VCPUS]; > }; > @@ -55,6 +56,7 @@ void perf_test_destroy_vm(struct kvm_vm *vm); > > void perf_test_set_write_percent(struct kvm_vm *vm, uint32_t write_percent); > void perf_test_set_random_seed(struct kvm_vm *vm, uint32_t random_seed); > +void perf_test_set_random_access(struct kvm_vm *vm, bool random_access); > > void perf_test_start_vcpu_threads(int vcpus, void (*vcpu_fn)(struct perf_test_vcpu_args *)); > void perf_test_join_vcpu_threads(int vcpus); > diff --git a/tools/testing/selftests/kvm/lib/perf_test_util.c b/tools/testing/selftests/kvm/lib/perf_test_util.c > index 1a6b69713337..84e442a028c0 100644 > --- a/tools/testing/selftests/kvm/lib/perf_test_util.c > +++ b/tools/testing/selftests/kvm/lib/perf_test_util.c > @@ -48,6 +48,7 @@ void perf_test_guest_code(uint32_t vcpu_idx) > struct perf_test_vcpu_args *vcpu_args = &pta->vcpu_args[vcpu_idx]; > uint64_t gva; > uint64_t pages; > + uint64_t addr; > uint32_t *rnd_arr = (uint32_t *)vcpu_args->random_array; > int i; > > @@ -59,7 +60,11 @@ void perf_test_guest_code(uint32_t vcpu_idx) > > while (true) { > for (i = 0; i < pages; i++) { > - uint64_t addr = gva + (i * pta->guest_page_size); > + if (pta->random_access) > + addr = gva + > + ((rnd_arr[i] % pages) * pta->guest_page_size); > + else > + addr = gva + (i * pta->guest_page_size); > > if (rnd_arr[i] % 100 < pta->write_percent) > *(uint64_t *)addr = 0x0123456789ABCDEF; I think addr and write_percent need two different random numbers. Otherwise, you will end up with a situation where all addresses where (rnd_arr[i] % 100 < pta->write_percent) will get a write (always). Something like this: 012345678 <= address wwwrrrwww 837561249 <= access order I think the best way to fix this is to abstract the random number reading into something like get_next_rand(), and use it twice per iteration. > @@ -271,6 +276,12 @@ void perf_test_set_random_seed(struct kvm_vm *vm, uint32_t random_seed) > sync_global_to_guest(vm, perf_test_args); > } > > +void perf_test_set_random_access(struct kvm_vm *vm, bool random_access) > +{ > + perf_test_args.random_access = random_access; > + sync_global_to_guest(vm, perf_test_args); > +} > + > uint64_t __weak perf_test_nested_pages(int nr_vcpus) > { > return 0; > -- > 2.37.1.595.g718a3a8f04-goog > Thanks, Ricardo
diff --git a/tools/testing/selftests/kvm/dirty_log_perf_test.c b/tools/testing/selftests/kvm/dirty_log_perf_test.c index 9226eeea79bc..af9754bda0a4 100644 --- a/tools/testing/selftests/kvm/dirty_log_perf_test.c +++ b/tools/testing/selftests/kvm/dirty_log_perf_test.c @@ -133,6 +133,7 @@ struct test_params { int slots; uint32_t write_percent; uint32_t random_seed; + bool random_access; }; static void toggle_dirty_logging(struct kvm_vm *vm, int slots, bool enable) @@ -271,6 +272,9 @@ static void run_test(enum vm_guest_mode mode, void *arg) pr_info("Enabling dirty logging time: %ld.%.9lds\n\n", ts_diff.tv_sec, ts_diff.tv_nsec); + /* Set random access here, after population phase. */ + perf_test_set_random_access(vm, p->random_access); + while (iteration < p->iterations) { /* * Incrementing the iteration number will start the vCPUs @@ -353,10 +357,11 @@ static void run_test(enum vm_guest_mode mode, void *arg) static void help(char *name) { puts(""); - printf("usage: %s [-h] [-i iterations] [-p offset] [-g] " + printf("usage: %s [-h] [-a] [-i iterations] [-p offset] [-g] " "[-m mode] [-n] [-b vcpu bytes] [-v vcpus] [-o] [-r random seed ] [-s mem type]" "[-x memslots] [-w percentage]\n", name); puts(""); + printf(" -a: access memory randomly rather than in order.\n"); printf(" -i: specify iteration counts (default: %"PRIu64")\n", TEST_HOST_LOOP_N); printf(" -g: Do not enable KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2. This\n" @@ -413,6 +418,9 @@ int main(int argc, char *argv[]) while ((opt = getopt(argc, argv, "eghi:p:m:nb:v:or:s:x:w:")) != -1) { switch (opt) { + case 'a': + p.random_access = true; + break; case 'e': /* 'e' is for evil. */ run_vcpus_while_disabling_dirty_logging = true; diff --git a/tools/testing/selftests/kvm/include/perf_test_util.h b/tools/testing/selftests/kvm/include/perf_test_util.h index 8da4a839c585..237899f3f4fe 100644 --- a/tools/testing/selftests/kvm/include/perf_test_util.h +++ b/tools/testing/selftests/kvm/include/perf_test_util.h @@ -41,6 +41,7 @@ struct perf_test_args { /* Run vCPUs in L2 instead of L1, if the architecture supports it. */ bool nested; + bool random_access; struct perf_test_vcpu_args vcpu_args[KVM_MAX_VCPUS]; }; @@ -55,6 +56,7 @@ void perf_test_destroy_vm(struct kvm_vm *vm); void perf_test_set_write_percent(struct kvm_vm *vm, uint32_t write_percent); void perf_test_set_random_seed(struct kvm_vm *vm, uint32_t random_seed); +void perf_test_set_random_access(struct kvm_vm *vm, bool random_access); void perf_test_start_vcpu_threads(int vcpus, void (*vcpu_fn)(struct perf_test_vcpu_args *)); void perf_test_join_vcpu_threads(int vcpus); diff --git a/tools/testing/selftests/kvm/lib/perf_test_util.c b/tools/testing/selftests/kvm/lib/perf_test_util.c index 1a6b69713337..84e442a028c0 100644 --- a/tools/testing/selftests/kvm/lib/perf_test_util.c +++ b/tools/testing/selftests/kvm/lib/perf_test_util.c @@ -48,6 +48,7 @@ void perf_test_guest_code(uint32_t vcpu_idx) struct perf_test_vcpu_args *vcpu_args = &pta->vcpu_args[vcpu_idx]; uint64_t gva; uint64_t pages; + uint64_t addr; uint32_t *rnd_arr = (uint32_t *)vcpu_args->random_array; int i; @@ -59,7 +60,11 @@ void perf_test_guest_code(uint32_t vcpu_idx) while (true) { for (i = 0; i < pages; i++) { - uint64_t addr = gva + (i * pta->guest_page_size); + if (pta->random_access) + addr = gva + + ((rnd_arr[i] % pages) * pta->guest_page_size); + else + addr = gva + (i * pta->guest_page_size); if (rnd_arr[i] % 100 < pta->write_percent) *(uint64_t *)addr = 0x0123456789ABCDEF; @@ -271,6 +276,12 @@ void perf_test_set_random_seed(struct kvm_vm *vm, uint32_t random_seed) sync_global_to_guest(vm, perf_test_args); } +void perf_test_set_random_access(struct kvm_vm *vm, bool random_access) +{ + perf_test_args.random_access = random_access; + sync_global_to_guest(vm, perf_test_args); +} + uint64_t __weak perf_test_nested_pages(int nr_vcpus) { return 0;
Create the ability to randomize page access order with the -a argument, including the possibility that the same pages may be hit multiple times during an iteration or not at all. Signed-off-by: Colton Lewis <coltonlewis@google.com> --- tools/testing/selftests/kvm/dirty_log_perf_test.c | 10 +++++++++- .../testing/selftests/kvm/include/perf_test_util.h | 2 ++ tools/testing/selftests/kvm/lib/perf_test_util.c | 13 ++++++++++++- 3 files changed, 23 insertions(+), 2 deletions(-)