| Message ID | 20240229010130.1380926-15-atishp@rivosinc.com |
|---|---|
| State | New |
| Headers | show |
| Series | RISC-V SBI v2.0 PMU improvements and Perf sampling in KVM guest | expand |
On Thu, Feb 29, 2024 at 6:32 AM Atish Patra <atishp@rivosinc.com> wrote: > > Verify PMU snapshot functionality by setting up the shared memory > correctly and reading the counter values from the shared memory > instead of the CSR. > > Signed-off-by: Atish Patra <atishp@rivosinc.com> LGTM. Reviewed-by: Anup Patel <anup@brainfault.org> Regards, Anup > --- > .../selftests/kvm/include/riscv/processor.h | 25 ++++ > .../selftests/kvm/lib/riscv/processor.c | 12 ++ > tools/testing/selftests/kvm/riscv/sbi_pmu.c | 124 ++++++++++++++++++ > 3 files changed, 161 insertions(+) > > diff --git a/tools/testing/selftests/kvm/include/riscv/processor.h b/tools/testing/selftests/kvm/include/riscv/processor.h > index a49a39c8e8d4..e114d039e87b 100644 > --- a/tools/testing/selftests/kvm/include/riscv/processor.h > +++ b/tools/testing/selftests/kvm/include/riscv/processor.h > @@ -173,6 +173,7 @@ enum sbi_ext_id { > }; > > enum sbi_ext_base_fid { > + SBI_EXT_BASE_GET_IMP_VERSION = 2, > SBI_EXT_BASE_PROBE_EXT = 3, > }; > > @@ -201,6 +202,12 @@ union sbi_pmu_ctr_info { > }; > }; > > +struct riscv_pmu_snapshot_data { > + u64 ctr_overflow_mask; > + u64 ctr_values[64]; > + u64 reserved[447]; > +}; > + > struct sbiret { > long error; > long value; > @@ -247,6 +254,14 @@ enum sbi_pmu_ctr_type { > #define SBI_PMU_STOP_FLAG_RESET (1 << 0) > #define SBI_PMU_STOP_FLAG_TAKE_SNAPSHOT BIT(1) > > +#define SBI_STA_SHMEM_DISABLE -1 > + > +/* SBI spec version fields */ > +#define SBI_SPEC_VERSION_DEFAULT 0x1 > +#define SBI_SPEC_VERSION_MAJOR_SHIFT 24 > +#define SBI_SPEC_VERSION_MAJOR_MASK 0x7f > +#define SBI_SPEC_VERSION_MINOR_MASK 0xffffff > + > struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0, > unsigned long arg1, unsigned long arg2, > unsigned long arg3, unsigned long arg4, > @@ -254,6 +269,16 @@ struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0, > > bool guest_sbi_probe_extension(int extid, long *out_val); > > +/* Make SBI version */ > +static inline unsigned long sbi_mk_version(unsigned long major, > + unsigned long minor) > +{ > + return ((major & SBI_SPEC_VERSION_MAJOR_MASK) << > + SBI_SPEC_VERSION_MAJOR_SHIFT) | minor; > +} > + > +unsigned long get_host_sbi_impl_version(void); > + > static inline void local_irq_enable(void) > { > csr_set(CSR_SSTATUS, SR_SIE); > diff --git a/tools/testing/selftests/kvm/lib/riscv/processor.c b/tools/testing/selftests/kvm/lib/riscv/processor.c > index ec66d331a127..b0162d923e38 100644 > --- a/tools/testing/selftests/kvm/lib/riscv/processor.c > +++ b/tools/testing/selftests/kvm/lib/riscv/processor.c > @@ -499,3 +499,15 @@ bool guest_sbi_probe_extension(int extid, long *out_val) > > return true; > } > + > +unsigned long get_host_sbi_impl_version(void) > +{ > + struct sbiret ret; > + > + ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_IMP_VERSION, 0, > + 0, 0, 0, 0, 0); > + > + GUEST_ASSERT(!ret.error); > + > + return ret.value; > +} > diff --git a/tools/testing/selftests/kvm/riscv/sbi_pmu.c b/tools/testing/selftests/kvm/riscv/sbi_pmu.c > index fc1fc5eea99e..8ea2a6db6610 100644 > --- a/tools/testing/selftests/kvm/riscv/sbi_pmu.c > +++ b/tools/testing/selftests/kvm/riscv/sbi_pmu.c > @@ -21,6 +21,11 @@ > #define RISCV_MAX_PMU_COUNTERS 64 > union sbi_pmu_ctr_info ctrinfo_arr[RISCV_MAX_PMU_COUNTERS]; > > +/* Snapshot shared memory data */ > +#define PMU_SNAPSHOT_GPA_BASE (1 << 30) > +static void *snapshot_gva; > +static vm_paddr_t snapshot_gpa; > + > /* Cache the available counters in a bitmask */ > static unsigned long counter_mask_available; > > @@ -173,6 +178,20 @@ static void stop_counter(unsigned long counter, unsigned long stop_flags) > counter, ret.error); > } > > +static void snapshot_set_shmem(vm_paddr_t gpa, unsigned long flags) > +{ > + unsigned long lo = (unsigned long)gpa; > +#if __riscv_xlen == 32 > + unsigned long hi = (unsigned long)(gpa >> 32); > +#else > + unsigned long hi = gpa == -1 ? -1 : 0; > +#endif > + struct sbiret ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_SNAPSHOT_SET_SHMEM, > + lo, hi, flags, 0, 0, 0); > + > + GUEST_ASSERT(ret.value == 0 && ret.error == 0); > +} > + > static void test_pmu_event(unsigned long event) > { > unsigned long counter; > @@ -207,6 +226,43 @@ static void test_pmu_event(unsigned long event) > stop_counter(counter, SBI_PMU_STOP_FLAG_RESET); > } > > +static void test_pmu_event_snapshot(unsigned long event) > +{ > + unsigned long counter; > + unsigned long counter_value_pre, counter_value_post; > + unsigned long counter_init_value = 100; > + struct riscv_pmu_snapshot_data *snapshot_data = snapshot_gva; > + > + counter = get_counter_index(0, counter_mask_available, 0, event); > + counter_value_pre = read_counter(counter, ctrinfo_arr[counter]); > + > + /* Do not set the initial value */ > + start_counter(counter, 0, 0); > + dummy_func_loop(10000); > + > + stop_counter(counter, SBI_PMU_STOP_FLAG_TAKE_SNAPSHOT); > + > + /* The counter value is updated w.r.t relative index of cbase */ > + counter_value_post = READ_ONCE(snapshot_data->ctr_values[0]); > + __GUEST_ASSERT(counter_value_post > counter_value_pre, > + "counter_value_post %lx counter_value_pre %lx\n", > + counter_value_post, counter_value_pre); > + > + /* Now set the initial value and compare */ > + WRITE_ONCE(snapshot_data->ctr_values[0], counter_init_value); > + start_counter(counter, SBI_PMU_START_FLAG_INIT_FROM_SNAPSHOT, 0); > + dummy_func_loop(10000); > + > + stop_counter(counter, SBI_PMU_STOP_FLAG_TAKE_SNAPSHOT); > + > + counter_value_post = READ_ONCE(snapshot_data->ctr_values[0]); > + __GUEST_ASSERT(counter_value_post > counter_init_value, > + "counter_value_post %lx counter_init_value %lx for counter\n", > + counter_value_post, counter_init_value); > + > + stop_counter(counter, SBI_PMU_STOP_FLAG_RESET); > +} > + > static void test_invalid_event(void) > { > struct sbiret ret; > @@ -270,6 +326,41 @@ static void test_pmu_basic_sanity(int cpu) > GUEST_DONE(); > } > > +static void test_pmu_events_snaphost(int cpu) > +{ > + long out_val = 0; > + bool probe; > + int num_counters = 0; > + unsigned long sbi_impl_version; > + struct riscv_pmu_snapshot_data *snapshot_data = snapshot_gva; > + int i; > + > + probe = guest_sbi_probe_extension(SBI_EXT_PMU, &out_val); > + GUEST_ASSERT(probe && out_val == 1); > + > + sbi_impl_version = get_host_sbi_impl_version(); > + if (sbi_impl_version >= sbi_mk_version(2, 0)) > + __GUEST_ASSERT(0, "SBI implementation version doesn't support PMU Snapshot"); > + > + snapshot_set_shmem(snapshot_gpa, 0); > + > + /* Get the counter details */ > + num_counters = get_num_counters(); > + update_counter_info(num_counters); > + > + /* Validate shared memory access */ > + GUEST_ASSERT_EQ(READ_ONCE(snapshot_data->ctr_overflow_mask), 0); > + for (i = 0; i < num_counters; i++) { > + if (counter_mask_available & (1UL << i)) > + GUEST_ASSERT_EQ(READ_ONCE(snapshot_data->ctr_values[i]), 0); > + } > + /* Only these two events are guranteed to be present */ > + test_pmu_event_snapshot(SBI_PMU_HW_CPU_CYCLES); > + test_pmu_event_snapshot(SBI_PMU_HW_INSTRUCTIONS); > + > + GUEST_DONE(); > +} > + > static void run_vcpu(struct kvm_vcpu *vcpu) > { > struct ucall uc; > @@ -328,6 +419,36 @@ static void test_vm_events_test(void *guest_code) > test_vm_destroy(vm); > } > > +static void test_vm_setup_snapshot_mem(struct kvm_vm *vm, struct kvm_vcpu *vcpu) > +{ > + vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, PMU_SNAPSHOT_GPA_BASE, 1, 1, 0); > + /* PMU Snapshot requires single page only */ > + virt_map(vm, PMU_SNAPSHOT_GPA_BASE, PMU_SNAPSHOT_GPA_BASE, 1); > + > + /* PMU_SNAPSHOT_GPA_BASE is identity mapped */ > + snapshot_gva = (void *)(PMU_SNAPSHOT_GPA_BASE); > + snapshot_gpa = addr_gva2gpa(vcpu->vm, (vm_vaddr_t)snapshot_gva); > + sync_global_to_guest(vcpu->vm, snapshot_gva); > + sync_global_to_guest(vcpu->vm, snapshot_gpa); > +} > + > +static void test_vm_events_snapshot_test(void *guest_code) > +{ > + struct kvm_vm *vm = NULL; > + struct kvm_vcpu *vcpu = NULL; > + > + vm = vm_create_with_one_vcpu(&vcpu, guest_code); > + __TEST_REQUIRE(__vcpu_has_ext(vcpu, RISCV_ISA_EXT_REG(KVM_RISCV_SBI_EXT_PMU)), > + "SBI PMU not available, skipping test"); > + > + test_vm_setup_snapshot_mem(vm, vcpu); > + > + vcpu_args_set(vcpu, 1, 0); > + run_vcpu(vcpu); > + > + test_vm_destroy(vm); > +} > + > int main(void) > { > test_vm_basic_test(test_pmu_basic_sanity); > @@ -336,5 +457,8 @@ int main(void) > test_vm_events_test(test_pmu_events); > pr_info("SBI PMU event verification test : PASS\n"); > > + test_vm_events_snapshot_test(test_pmu_events_snaphost); > + pr_info("SBI PMU event verification with snapshot test : PASS\n"); > + > return 0; > } > -- > 2.34.1 >
On Wed, Feb 28, 2024 at 05:01:29PM -0800, Atish Patra wrote: > Verify PMU snapshot functionality by setting up the shared memory > correctly and reading the counter values from the shared memory > instead of the CSR. > > Signed-off-by: Atish Patra <atishp@rivosinc.com> > --- > .../selftests/kvm/include/riscv/processor.h | 25 ++++ > .../selftests/kvm/lib/riscv/processor.c | 12 ++ > tools/testing/selftests/kvm/riscv/sbi_pmu.c | 124 ++++++++++++++++++ > 3 files changed, 161 insertions(+) > > diff --git a/tools/testing/selftests/kvm/include/riscv/processor.h b/tools/testing/selftests/kvm/include/riscv/processor.h > index a49a39c8e8d4..e114d039e87b 100644 > --- a/tools/testing/selftests/kvm/include/riscv/processor.h > +++ b/tools/testing/selftests/kvm/include/riscv/processor.h > @@ -173,6 +173,7 @@ enum sbi_ext_id { > }; > > enum sbi_ext_base_fid { > + SBI_EXT_BASE_GET_IMP_VERSION = 2, > SBI_EXT_BASE_PROBE_EXT = 3, > }; > > @@ -201,6 +202,12 @@ union sbi_pmu_ctr_info { > }; > }; > > +struct riscv_pmu_snapshot_data { > + u64 ctr_overflow_mask; > + u64 ctr_values[64]; > + u64 reserved[447]; > +}; > + > struct sbiret { > long error; > long value; > @@ -247,6 +254,14 @@ enum sbi_pmu_ctr_type { > #define SBI_PMU_STOP_FLAG_RESET (1 << 0) > #define SBI_PMU_STOP_FLAG_TAKE_SNAPSHOT BIT(1) > > +#define SBI_STA_SHMEM_DISABLE -1 unrelated change > + > +/* SBI spec version fields */ > +#define SBI_SPEC_VERSION_DEFAULT 0x1 > +#define SBI_SPEC_VERSION_MAJOR_SHIFT 24 > +#define SBI_SPEC_VERSION_MAJOR_MASK 0x7f > +#define SBI_SPEC_VERSION_MINOR_MASK 0xffffff > + > struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0, > unsigned long arg1, unsigned long arg2, > unsigned long arg3, unsigned long arg4, > @@ -254,6 +269,16 @@ struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0, > > bool guest_sbi_probe_extension(int extid, long *out_val); > > +/* Make SBI version */ > +static inline unsigned long sbi_mk_version(unsigned long major, > + unsigned long minor) > +{ > + return ((major & SBI_SPEC_VERSION_MAJOR_MASK) << > + SBI_SPEC_VERSION_MAJOR_SHIFT) | minor; > +} We should probably just synch sbi.h into tools, since we need plenty from it. > + > +unsigned long get_host_sbi_impl_version(void); > + > static inline void local_irq_enable(void) > { > csr_set(CSR_SSTATUS, SR_SIE); > diff --git a/tools/testing/selftests/kvm/lib/riscv/processor.c b/tools/testing/selftests/kvm/lib/riscv/processor.c > index ec66d331a127..b0162d923e38 100644 > --- a/tools/testing/selftests/kvm/lib/riscv/processor.c > +++ b/tools/testing/selftests/kvm/lib/riscv/processor.c > @@ -499,3 +499,15 @@ bool guest_sbi_probe_extension(int extid, long *out_val) > > return true; > } > + > +unsigned long get_host_sbi_impl_version(void) > +{ > + struct sbiret ret; > + > + ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_IMP_VERSION, 0, > + 0, 0, 0, 0, 0); > + > + GUEST_ASSERT(!ret.error); > + > + return ret.value; > +} > diff --git a/tools/testing/selftests/kvm/riscv/sbi_pmu.c b/tools/testing/selftests/kvm/riscv/sbi_pmu.c > index fc1fc5eea99e..8ea2a6db6610 100644 > --- a/tools/testing/selftests/kvm/riscv/sbi_pmu.c > +++ b/tools/testing/selftests/kvm/riscv/sbi_pmu.c > @@ -21,6 +21,11 @@ > #define RISCV_MAX_PMU_COUNTERS 64 > union sbi_pmu_ctr_info ctrinfo_arr[RISCV_MAX_PMU_COUNTERS]; > > +/* Snapshot shared memory data */ > +#define PMU_SNAPSHOT_GPA_BASE (1 << 30) > +static void *snapshot_gva; > +static vm_paddr_t snapshot_gpa; > + > /* Cache the available counters in a bitmask */ > static unsigned long counter_mask_available; > > @@ -173,6 +178,20 @@ static void stop_counter(unsigned long counter, unsigned long stop_flags) > counter, ret.error); > } > > +static void snapshot_set_shmem(vm_paddr_t gpa, unsigned long flags) > +{ > + unsigned long lo = (unsigned long)gpa; > +#if __riscv_xlen == 32 > + unsigned long hi = (unsigned long)(gpa >> 32); > +#else > + unsigned long hi = gpa == -1 ? -1 : 0; > +#endif > + struct sbiret ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_SNAPSHOT_SET_SHMEM, > + lo, hi, flags, 0, 0, 0); > + > + GUEST_ASSERT(ret.value == 0 && ret.error == 0); > +} > + > static void test_pmu_event(unsigned long event) > { > unsigned long counter; > @@ -207,6 +226,43 @@ static void test_pmu_event(unsigned long event) > stop_counter(counter, SBI_PMU_STOP_FLAG_RESET); > } > > +static void test_pmu_event_snapshot(unsigned long event) > +{ > + unsigned long counter; > + unsigned long counter_value_pre, counter_value_post; > + unsigned long counter_init_value = 100; > + struct riscv_pmu_snapshot_data *snapshot_data = snapshot_gva; > + > + counter = get_counter_index(0, counter_mask_available, 0, event); > + counter_value_pre = read_counter(counter, ctrinfo_arr[counter]); > + > + /* Do not set the initial value */ > + start_counter(counter, 0, 0); > + dummy_func_loop(10000); > + > + stop_counter(counter, SBI_PMU_STOP_FLAG_TAKE_SNAPSHOT); > + > + /* The counter value is updated w.r.t relative index of cbase */ > + counter_value_post = READ_ONCE(snapshot_data->ctr_values[0]); > + __GUEST_ASSERT(counter_value_post > counter_value_pre, > + "counter_value_post %lx counter_value_pre %lx\n", > + counter_value_post, counter_value_pre); > + > + /* Now set the initial value and compare */ > + WRITE_ONCE(snapshot_data->ctr_values[0], counter_init_value); > + start_counter(counter, SBI_PMU_START_FLAG_INIT_FROM_SNAPSHOT, 0); > + dummy_func_loop(10000); > + > + stop_counter(counter, SBI_PMU_STOP_FLAG_TAKE_SNAPSHOT); > + > + counter_value_post = READ_ONCE(snapshot_data->ctr_values[0]); > + __GUEST_ASSERT(counter_value_post > counter_init_value, > + "counter_value_post %lx counter_init_value %lx for counter\n", > + counter_value_post, counter_init_value); > + > + stop_counter(counter, SBI_PMU_STOP_FLAG_RESET); This function is almost identical to test_pmu_event(). If we change one, we'll likely have to change the other. We should have a single function which can be used by both tests. We can do that by passing a function pointer for the read which is different for non-snapshot and snapshot. > +} > + > static void test_invalid_event(void) > { > struct sbiret ret; > @@ -270,6 +326,41 @@ static void test_pmu_basic_sanity(int cpu) > GUEST_DONE(); > } > > +static void test_pmu_events_snaphost(int cpu) unnecessary cpu parameter > +{ > + long out_val = 0; > + bool probe; > + int num_counters = 0; > + unsigned long sbi_impl_version; > + struct riscv_pmu_snapshot_data *snapshot_data = snapshot_gva; > + int i; > + > + probe = guest_sbi_probe_extension(SBI_EXT_PMU, &out_val); > + GUEST_ASSERT(probe && out_val == 1); > + > + sbi_impl_version = get_host_sbi_impl_version(); > + if (sbi_impl_version >= sbi_mk_version(2, 0)) > + __GUEST_ASSERT(0, "SBI implementation version doesn't support PMU Snapshot"); > + > + snapshot_set_shmem(snapshot_gpa, 0); > + > + /* Get the counter details */ > + num_counters = get_num_counters(); > + update_counter_info(num_counters); > + > + /* Validate shared memory access */ > + GUEST_ASSERT_EQ(READ_ONCE(snapshot_data->ctr_overflow_mask), 0); > + for (i = 0; i < num_counters; i++) { > + if (counter_mask_available & (1UL << i)) BIT() > + GUEST_ASSERT_EQ(READ_ONCE(snapshot_data->ctr_values[i]), 0); > + } > + /* Only these two events are guranteed to be present */ > + test_pmu_event_snapshot(SBI_PMU_HW_CPU_CYCLES); > + test_pmu_event_snapshot(SBI_PMU_HW_INSTRUCTIONS); > + > + GUEST_DONE(); > +} > + > static void run_vcpu(struct kvm_vcpu *vcpu) > { > struct ucall uc; > @@ -328,6 +419,36 @@ static void test_vm_events_test(void *guest_code) > test_vm_destroy(vm); > } > > +static void test_vm_setup_snapshot_mem(struct kvm_vm *vm, struct kvm_vcpu *vcpu) > +{ > + vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, PMU_SNAPSHOT_GPA_BASE, 1, 1, 0); > + /* PMU Snapshot requires single page only */ This comment should go above the memory region add > + virt_map(vm, PMU_SNAPSHOT_GPA_BASE, PMU_SNAPSHOT_GPA_BASE, 1); > + > + /* PMU_SNAPSHOT_GPA_BASE is identity mapped */ This comment should go above the virt_map > + snapshot_gva = (void *)(PMU_SNAPSHOT_GPA_BASE); > + snapshot_gpa = addr_gva2gpa(vcpu->vm, (vm_vaddr_t)snapshot_gva); > + sync_global_to_guest(vcpu->vm, snapshot_gva); > + sync_global_to_guest(vcpu->vm, snapshot_gpa); > +} > + > +static void test_vm_events_snapshot_test(void *guest_code) > +{ > + struct kvm_vm *vm = NULL; > + struct kvm_vcpu *vcpu = NULL; nit: no need to set to NULL > + > + vm = vm_create_with_one_vcpu(&vcpu, guest_code); > + __TEST_REQUIRE(__vcpu_has_ext(vcpu, RISCV_ISA_EXT_REG(KVM_RISCV_SBI_EXT_PMU)), RISCV_SBI_EXT_REG > + "SBI PMU not available, skipping test"); > + > + test_vm_setup_snapshot_mem(vm, vcpu); > + > + vcpu_args_set(vcpu, 1, 0); no need to set args > + run_vcpu(vcpu); > + > + test_vm_destroy(vm); > +} > + > int main(void) > { > test_vm_basic_test(test_pmu_basic_sanity); > @@ -336,5 +457,8 @@ int main(void) > test_vm_events_test(test_pmu_events); > pr_info("SBI PMU event verification test : PASS\n"); > > + test_vm_events_snapshot_test(test_pmu_events_snaphost); > + pr_info("SBI PMU event verification with snapshot test : PASS\n"); > + > return 0; > } > -- > 2.34.1 > Thanks, drew
On 3/2/24 04:13, Andrew Jones wrote: > On Wed, Feb 28, 2024 at 05:01:29PM -0800, Atish Patra wrote: >> Verify PMU snapshot functionality by setting up the shared memory >> correctly and reading the counter values from the shared memory >> instead of the CSR. >> >> Signed-off-by: Atish Patra <atishp@rivosinc.com> >> --- >> .../selftests/kvm/include/riscv/processor.h | 25 ++++ >> .../selftests/kvm/lib/riscv/processor.c | 12 ++ >> tools/testing/selftests/kvm/riscv/sbi_pmu.c | 124 ++++++++++++++++++ >> 3 files changed, 161 insertions(+) >> >> diff --git a/tools/testing/selftests/kvm/include/riscv/processor.h b/tools/testing/selftests/kvm/include/riscv/processor.h >> index a49a39c8e8d4..e114d039e87b 100644 >> --- a/tools/testing/selftests/kvm/include/riscv/processor.h >> +++ b/tools/testing/selftests/kvm/include/riscv/processor.h >> @@ -173,6 +173,7 @@ enum sbi_ext_id { >> }; >> >> enum sbi_ext_base_fid { >> + SBI_EXT_BASE_GET_IMP_VERSION = 2, >> SBI_EXT_BASE_PROBE_EXT = 3, >> }; >> >> @@ -201,6 +202,12 @@ union sbi_pmu_ctr_info { >> }; >> }; >> >> +struct riscv_pmu_snapshot_data { >> + u64 ctr_overflow_mask; >> + u64 ctr_values[64]; >> + u64 reserved[447]; >> +}; >> + >> struct sbiret { >> long error; >> long value; >> @@ -247,6 +254,14 @@ enum sbi_pmu_ctr_type { >> #define SBI_PMU_STOP_FLAG_RESET (1 << 0) >> #define SBI_PMU_STOP_FLAG_TAKE_SNAPSHOT BIT(1) >> >> +#define SBI_STA_SHMEM_DISABLE -1 > > unrelated change > Dropped it. >> + >> +/* SBI spec version fields */ >> +#define SBI_SPEC_VERSION_DEFAULT 0x1 >> +#define SBI_SPEC_VERSION_MAJOR_SHIFT 24 >> +#define SBI_SPEC_VERSION_MAJOR_MASK 0x7f >> +#define SBI_SPEC_VERSION_MINOR_MASK 0xffffff >> + >> struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0, >> unsigned long arg1, unsigned long arg2, >> unsigned long arg3, unsigned long arg4, >> @@ -254,6 +269,16 @@ struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0, >> >> bool guest_sbi_probe_extension(int extid, long *out_val); >> >> +/* Make SBI version */ >> +static inline unsigned long sbi_mk_version(unsigned long major, >> + unsigned long minor) >> +{ >> + return ((major & SBI_SPEC_VERSION_MAJOR_MASK) << >> + SBI_SPEC_VERSION_MAJOR_SHIFT) | minor; >> +} > > We should probably just synch sbi.h into tools, since we need plenty > from it. > As of now I have created sbi.h and moved all the definitions there. There is a still lot of difference between sbi.h. Do we really want to bring everything in ? Should we adopt kvmtool like policy to sync sbi.h or just do it as new test cases need sbi.h? I can send another version with syncing sbi.h if you still think that's better. >> + >> +unsigned long get_host_sbi_impl_version(void); >> + >> static inline void local_irq_enable(void) >> { >> csr_set(CSR_SSTATUS, SR_SIE); >> diff --git a/tools/testing/selftests/kvm/lib/riscv/processor.c b/tools/testing/selftests/kvm/lib/riscv/processor.c >> index ec66d331a127..b0162d923e38 100644 >> --- a/tools/testing/selftests/kvm/lib/riscv/processor.c >> +++ b/tools/testing/selftests/kvm/lib/riscv/processor.c >> @@ -499,3 +499,15 @@ bool guest_sbi_probe_extension(int extid, long *out_val) >> >> return true; >> } >> + >> +unsigned long get_host_sbi_impl_version(void) >> +{ >> + struct sbiret ret; >> + >> + ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_IMP_VERSION, 0, >> + 0, 0, 0, 0, 0); >> + >> + GUEST_ASSERT(!ret.error); >> + >> + return ret.value; >> +} >> diff --git a/tools/testing/selftests/kvm/riscv/sbi_pmu.c b/tools/testing/selftests/kvm/riscv/sbi_pmu.c >> index fc1fc5eea99e..8ea2a6db6610 100644 >> --- a/tools/testing/selftests/kvm/riscv/sbi_pmu.c >> +++ b/tools/testing/selftests/kvm/riscv/sbi_pmu.c >> @@ -21,6 +21,11 @@ >> #define RISCV_MAX_PMU_COUNTERS 64 >> union sbi_pmu_ctr_info ctrinfo_arr[RISCV_MAX_PMU_COUNTERS]; >> >> +/* Snapshot shared memory data */ >> +#define PMU_SNAPSHOT_GPA_BASE (1 << 30) >> +static void *snapshot_gva; >> +static vm_paddr_t snapshot_gpa; >> + >> /* Cache the available counters in a bitmask */ >> static unsigned long counter_mask_available; >> >> @@ -173,6 +178,20 @@ static void stop_counter(unsigned long counter, unsigned long stop_flags) >> counter, ret.error); >> } >> >> +static void snapshot_set_shmem(vm_paddr_t gpa, unsigned long flags) >> +{ >> + unsigned long lo = (unsigned long)gpa; >> +#if __riscv_xlen == 32 >> + unsigned long hi = (unsigned long)(gpa >> 32); >> +#else >> + unsigned long hi = gpa == -1 ? -1 : 0; >> +#endif >> + struct sbiret ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_SNAPSHOT_SET_SHMEM, >> + lo, hi, flags, 0, 0, 0); >> + >> + GUEST_ASSERT(ret.value == 0 && ret.error == 0); >> +} >> + >> static void test_pmu_event(unsigned long event) >> { >> unsigned long counter; >> @@ -207,6 +226,43 @@ static void test_pmu_event(unsigned long event) >> stop_counter(counter, SBI_PMU_STOP_FLAG_RESET); >> } >> >> +static void test_pmu_event_snapshot(unsigned long event) >> +{ >> + unsigned long counter; >> + unsigned long counter_value_pre, counter_value_post; >> + unsigned long counter_init_value = 100; >> + struct riscv_pmu_snapshot_data *snapshot_data = snapshot_gva; >> + >> + counter = get_counter_index(0, counter_mask_available, 0, event); >> + counter_value_pre = read_counter(counter, ctrinfo_arr[counter]); >> + >> + /* Do not set the initial value */ >> + start_counter(counter, 0, 0); >> + dummy_func_loop(10000); >> + >> + stop_counter(counter, SBI_PMU_STOP_FLAG_TAKE_SNAPSHOT); >> + >> + /* The counter value is updated w.r.t relative index of cbase */ >> + counter_value_post = READ_ONCE(snapshot_data->ctr_values[0]); >> + __GUEST_ASSERT(counter_value_post > counter_value_pre, >> + "counter_value_post %lx counter_value_pre %lx\n", >> + counter_value_post, counter_value_pre); >> + >> + /* Now set the initial value and compare */ >> + WRITE_ONCE(snapshot_data->ctr_values[0], counter_init_value); >> + start_counter(counter, SBI_PMU_START_FLAG_INIT_FROM_SNAPSHOT, 0); >> + dummy_func_loop(10000); >> + >> + stop_counter(counter, SBI_PMU_STOP_FLAG_TAKE_SNAPSHOT); >> + >> + counter_value_post = READ_ONCE(snapshot_data->ctr_values[0]); >> + __GUEST_ASSERT(counter_value_post > counter_init_value, >> + "counter_value_post %lx counter_init_value %lx for counter\n", >> + counter_value_post, counter_init_value); >> + >> + stop_counter(counter, SBI_PMU_STOP_FLAG_RESET); > > This function is almost identical to test_pmu_event(). If we change one, > we'll likely have to change the other. We should have a single function > which can be used by both tests. We can do that by passing a function > pointer for the read which is different for non-snapshot and snapshot. > There are more difference than just read function. Stop/start takes snapshot specific flag. We also have to update the counter in the shared memory. If we combine the two functions to a single one, we will end up with bunch of if else condition which I don't like. I am okay modifying it if you feel strongly about it though. >> +} >> + >> static void test_invalid_event(void) >> { >> struct sbiret ret; >> @@ -270,6 +326,41 @@ static void test_pmu_basic_sanity(int cpu) >> GUEST_DONE(); >> } >> >> +static void test_pmu_events_snaphost(int cpu) > > unnecessary cpu parameter > Removed. >> +{ >> + long out_val = 0; >> + bool probe; >> + int num_counters = 0; >> + unsigned long sbi_impl_version; >> + struct riscv_pmu_snapshot_data *snapshot_data = snapshot_gva; >> + int i; >> + >> + probe = guest_sbi_probe_extension(SBI_EXT_PMU, &out_val); >> + GUEST_ASSERT(probe && out_val == 1); >> + >> + sbi_impl_version = get_host_sbi_impl_version(); >> + if (sbi_impl_version >= sbi_mk_version(2, 0)) >> + __GUEST_ASSERT(0, "SBI implementation version doesn't support PMU Snapshot"); >> + >> + snapshot_set_shmem(snapshot_gpa, 0); >> + >> + /* Get the counter details */ >> + num_counters = get_num_counters(); >> + update_counter_info(num_counters); >> + >> + /* Validate shared memory access */ >> + GUEST_ASSERT_EQ(READ_ONCE(snapshot_data->ctr_overflow_mask), 0); >> + for (i = 0; i < num_counters; i++) { >> + if (counter_mask_available & (1UL << i)) > > BIT() > Done. >> + GUEST_ASSERT_EQ(READ_ONCE(snapshot_data->ctr_values[i]), 0); >> + } >> + /* Only these two events are guranteed to be present */ >> + test_pmu_event_snapshot(SBI_PMU_HW_CPU_CYCLES); >> + test_pmu_event_snapshot(SBI_PMU_HW_INSTRUCTIONS); >> + >> + GUEST_DONE(); >> +} >> + >> static void run_vcpu(struct kvm_vcpu *vcpu) >> { >> struct ucall uc; >> @@ -328,6 +419,36 @@ static void test_vm_events_test(void *guest_code) >> test_vm_destroy(vm); >> } >> >> +static void test_vm_setup_snapshot_mem(struct kvm_vm *vm, struct kvm_vcpu *vcpu) >> +{ >> + vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, PMU_SNAPSHOT_GPA_BASE, 1, 1, 0); >> + /* PMU Snapshot requires single page only */ > > This comment should go above the memory region add > >> + virt_map(vm, PMU_SNAPSHOT_GPA_BASE, PMU_SNAPSHOT_GPA_BASE, 1); >> + >> + /* PMU_SNAPSHOT_GPA_BASE is identity mapped */ > > This comment should go above the virt_map > Fixed. >> + snapshot_gva = (void *)(PMU_SNAPSHOT_GPA_BASE); >> + snapshot_gpa = addr_gva2gpa(vcpu->vm, (vm_vaddr_t)snapshot_gva); >> + sync_global_to_guest(vcpu->vm, snapshot_gva); >> + sync_global_to_guest(vcpu->vm, snapshot_gpa); >> +} >> + >> +static void test_vm_events_snapshot_test(void *guest_code) >> +{ >> + struct kvm_vm *vm = NULL; >> + struct kvm_vcpu *vcpu = NULL; > > nit: no need to set to NULL > >> + >> + vm = vm_create_with_one_vcpu(&vcpu, guest_code); >> + __TEST_REQUIRE(__vcpu_has_ext(vcpu, RISCV_ISA_EXT_REG(KVM_RISCV_SBI_EXT_PMU)), > > RISCV_SBI_EXT_REG > Updated to use the new helper functions as suggested in the earlier patch. >> + "SBI PMU not available, skipping test"); >> + >> + test_vm_setup_snapshot_mem(vm, vcpu); >> + >> + vcpu_args_set(vcpu, 1, 0); > > no need to set args > Fixed. >> + run_vcpu(vcpu); >> + >> + test_vm_destroy(vm); >> +} >> + >> int main(void) >> { >> test_vm_basic_test(test_pmu_basic_sanity); >> @@ -336,5 +457,8 @@ int main(void) >> test_vm_events_test(test_pmu_events); >> pr_info("SBI PMU event verification test : PASS\n"); >> >> + test_vm_events_snapshot_test(test_pmu_events_snaphost); >> + pr_info("SBI PMU event verification with snapshot test : PASS\n"); >> + >> return 0; >> } >> -- >> 2.34.1 >> > > Thanks, > drew
diff --git a/tools/testing/selftests/kvm/include/riscv/processor.h b/tools/testing/selftests/kvm/include/riscv/processor.h index a49a39c8e8d4..e114d039e87b 100644 --- a/tools/testing/selftests/kvm/include/riscv/processor.h +++ b/tools/testing/selftests/kvm/include/riscv/processor.h @@ -173,6 +173,7 @@ enum sbi_ext_id { }; enum sbi_ext_base_fid { + SBI_EXT_BASE_GET_IMP_VERSION = 2, SBI_EXT_BASE_PROBE_EXT = 3, }; @@ -201,6 +202,12 @@ union sbi_pmu_ctr_info { }; }; +struct riscv_pmu_snapshot_data { + u64 ctr_overflow_mask; + u64 ctr_values[64]; + u64 reserved[447]; +}; + struct sbiret { long error; long value; @@ -247,6 +254,14 @@ enum sbi_pmu_ctr_type { #define SBI_PMU_STOP_FLAG_RESET (1 << 0) #define SBI_PMU_STOP_FLAG_TAKE_SNAPSHOT BIT(1) +#define SBI_STA_SHMEM_DISABLE -1 + +/* SBI spec version fields */ +#define SBI_SPEC_VERSION_DEFAULT 0x1 +#define SBI_SPEC_VERSION_MAJOR_SHIFT 24 +#define SBI_SPEC_VERSION_MAJOR_MASK 0x7f +#define SBI_SPEC_VERSION_MINOR_MASK 0xffffff + struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0, unsigned long arg1, unsigned long arg2, unsigned long arg3, unsigned long arg4, @@ -254,6 +269,16 @@ struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0, bool guest_sbi_probe_extension(int extid, long *out_val); +/* Make SBI version */ +static inline unsigned long sbi_mk_version(unsigned long major, + unsigned long minor) +{ + return ((major & SBI_SPEC_VERSION_MAJOR_MASK) << + SBI_SPEC_VERSION_MAJOR_SHIFT) | minor; +} + +unsigned long get_host_sbi_impl_version(void); + static inline void local_irq_enable(void) { csr_set(CSR_SSTATUS, SR_SIE); diff --git a/tools/testing/selftests/kvm/lib/riscv/processor.c b/tools/testing/selftests/kvm/lib/riscv/processor.c index ec66d331a127..b0162d923e38 100644 --- a/tools/testing/selftests/kvm/lib/riscv/processor.c +++ b/tools/testing/selftests/kvm/lib/riscv/processor.c @@ -499,3 +499,15 @@ bool guest_sbi_probe_extension(int extid, long *out_val) return true; } + +unsigned long get_host_sbi_impl_version(void) +{ + struct sbiret ret; + + ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_IMP_VERSION, 0, + 0, 0, 0, 0, 0); + + GUEST_ASSERT(!ret.error); + + return ret.value; +} diff --git a/tools/testing/selftests/kvm/riscv/sbi_pmu.c b/tools/testing/selftests/kvm/riscv/sbi_pmu.c index fc1fc5eea99e..8ea2a6db6610 100644 --- a/tools/testing/selftests/kvm/riscv/sbi_pmu.c +++ b/tools/testing/selftests/kvm/riscv/sbi_pmu.c @@ -21,6 +21,11 @@ #define RISCV_MAX_PMU_COUNTERS 64 union sbi_pmu_ctr_info ctrinfo_arr[RISCV_MAX_PMU_COUNTERS]; +/* Snapshot shared memory data */ +#define PMU_SNAPSHOT_GPA_BASE (1 << 30) +static void *snapshot_gva; +static vm_paddr_t snapshot_gpa; + /* Cache the available counters in a bitmask */ static unsigned long counter_mask_available; @@ -173,6 +178,20 @@ static void stop_counter(unsigned long counter, unsigned long stop_flags) counter, ret.error); } +static void snapshot_set_shmem(vm_paddr_t gpa, unsigned long flags) +{ + unsigned long lo = (unsigned long)gpa; +#if __riscv_xlen == 32 + unsigned long hi = (unsigned long)(gpa >> 32); +#else + unsigned long hi = gpa == -1 ? -1 : 0; +#endif + struct sbiret ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_SNAPSHOT_SET_SHMEM, + lo, hi, flags, 0, 0, 0); + + GUEST_ASSERT(ret.value == 0 && ret.error == 0); +} + static void test_pmu_event(unsigned long event) { unsigned long counter; @@ -207,6 +226,43 @@ static void test_pmu_event(unsigned long event) stop_counter(counter, SBI_PMU_STOP_FLAG_RESET); } +static void test_pmu_event_snapshot(unsigned long event) +{ + unsigned long counter; + unsigned long counter_value_pre, counter_value_post; + unsigned long counter_init_value = 100; + struct riscv_pmu_snapshot_data *snapshot_data = snapshot_gva; + + counter = get_counter_index(0, counter_mask_available, 0, event); + counter_value_pre = read_counter(counter, ctrinfo_arr[counter]); + + /* Do not set the initial value */ + start_counter(counter, 0, 0); + dummy_func_loop(10000); + + stop_counter(counter, SBI_PMU_STOP_FLAG_TAKE_SNAPSHOT); + + /* The counter value is updated w.r.t relative index of cbase */ + counter_value_post = READ_ONCE(snapshot_data->ctr_values[0]); + __GUEST_ASSERT(counter_value_post > counter_value_pre, + "counter_value_post %lx counter_value_pre %lx\n", + counter_value_post, counter_value_pre); + + /* Now set the initial value and compare */ + WRITE_ONCE(snapshot_data->ctr_values[0], counter_init_value); + start_counter(counter, SBI_PMU_START_FLAG_INIT_FROM_SNAPSHOT, 0); + dummy_func_loop(10000); + + stop_counter(counter, SBI_PMU_STOP_FLAG_TAKE_SNAPSHOT); + + counter_value_post = READ_ONCE(snapshot_data->ctr_values[0]); + __GUEST_ASSERT(counter_value_post > counter_init_value, + "counter_value_post %lx counter_init_value %lx for counter\n", + counter_value_post, counter_init_value); + + stop_counter(counter, SBI_PMU_STOP_FLAG_RESET); +} + static void test_invalid_event(void) { struct sbiret ret; @@ -270,6 +326,41 @@ static void test_pmu_basic_sanity(int cpu) GUEST_DONE(); } +static void test_pmu_events_snaphost(int cpu) +{ + long out_val = 0; + bool probe; + int num_counters = 0; + unsigned long sbi_impl_version; + struct riscv_pmu_snapshot_data *snapshot_data = snapshot_gva; + int i; + + probe = guest_sbi_probe_extension(SBI_EXT_PMU, &out_val); + GUEST_ASSERT(probe && out_val == 1); + + sbi_impl_version = get_host_sbi_impl_version(); + if (sbi_impl_version >= sbi_mk_version(2, 0)) + __GUEST_ASSERT(0, "SBI implementation version doesn't support PMU Snapshot"); + + snapshot_set_shmem(snapshot_gpa, 0); + + /* Get the counter details */ + num_counters = get_num_counters(); + update_counter_info(num_counters); + + /* Validate shared memory access */ + GUEST_ASSERT_EQ(READ_ONCE(snapshot_data->ctr_overflow_mask), 0); + for (i = 0; i < num_counters; i++) { + if (counter_mask_available & (1UL << i)) + GUEST_ASSERT_EQ(READ_ONCE(snapshot_data->ctr_values[i]), 0); + } + /* Only these two events are guranteed to be present */ + test_pmu_event_snapshot(SBI_PMU_HW_CPU_CYCLES); + test_pmu_event_snapshot(SBI_PMU_HW_INSTRUCTIONS); + + GUEST_DONE(); +} + static void run_vcpu(struct kvm_vcpu *vcpu) { struct ucall uc; @@ -328,6 +419,36 @@ static void test_vm_events_test(void *guest_code) test_vm_destroy(vm); } +static void test_vm_setup_snapshot_mem(struct kvm_vm *vm, struct kvm_vcpu *vcpu) +{ + vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, PMU_SNAPSHOT_GPA_BASE, 1, 1, 0); + /* PMU Snapshot requires single page only */ + virt_map(vm, PMU_SNAPSHOT_GPA_BASE, PMU_SNAPSHOT_GPA_BASE, 1); + + /* PMU_SNAPSHOT_GPA_BASE is identity mapped */ + snapshot_gva = (void *)(PMU_SNAPSHOT_GPA_BASE); + snapshot_gpa = addr_gva2gpa(vcpu->vm, (vm_vaddr_t)snapshot_gva); + sync_global_to_guest(vcpu->vm, snapshot_gva); + sync_global_to_guest(vcpu->vm, snapshot_gpa); +} + +static void test_vm_events_snapshot_test(void *guest_code) +{ + struct kvm_vm *vm = NULL; + struct kvm_vcpu *vcpu = NULL; + + vm = vm_create_with_one_vcpu(&vcpu, guest_code); + __TEST_REQUIRE(__vcpu_has_ext(vcpu, RISCV_ISA_EXT_REG(KVM_RISCV_SBI_EXT_PMU)), + "SBI PMU not available, skipping test"); + + test_vm_setup_snapshot_mem(vm, vcpu); + + vcpu_args_set(vcpu, 1, 0); + run_vcpu(vcpu); + + test_vm_destroy(vm); +} + int main(void) { test_vm_basic_test(test_pmu_basic_sanity); @@ -336,5 +457,8 @@ int main(void) test_vm_events_test(test_pmu_events); pr_info("SBI PMU event verification test : PASS\n"); + test_vm_events_snapshot_test(test_pmu_events_snaphost); + pr_info("SBI PMU event verification with snapshot test : PASS\n"); + return 0; }
Verify PMU snapshot functionality by setting up the shared memory correctly and reading the counter values from the shared memory instead of the CSR. Signed-off-by: Atish Patra <atishp@rivosinc.com> --- .../selftests/kvm/include/riscv/processor.h | 25 ++++ .../selftests/kvm/lib/riscv/processor.c | 12 ++ tools/testing/selftests/kvm/riscv/sbi_pmu.c | 124 ++++++++++++++++++ 3 files changed, 161 insertions(+)