On Thu, Sep 14, 2023 at 09:37:03AM +0800, Haibo Xu wrote:
> Add a KVM selftests to validate the Sstc timer functionality.
> The test was ported from arm64 arch timer test.
>
> Signed-off-by: Haibo Xu <haibo1.xu@xxxxxxxxx>
> ---
> tools/testing/selftests/kvm/Makefile | 1 +
> .../selftests/kvm/aarch64/arch_timer.c | 12 +-
> tools/testing/selftests/kvm/arch_timer.c | 10 +-
> .../selftests/kvm/include/riscv/arch_timer.h | 80 +++++++++++++
> .../selftests/kvm/include/riscv/processor.h | 10 ++
> .../selftests/kvm/include/timer_test.h | 3 +-
> .../testing/selftests/kvm/riscv/arch_timer.c | 107 ++++++++++++++++++
> 7 files changed, 214 insertions(+), 9 deletions(-)
> create mode 100644 tools/testing/selftests/kvm/include/riscv/arch_timer.h
> create mode 100644 tools/testing/selftests/kvm/riscv/arch_timer.c
>
> diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
> index a5bc8e156047..73d393a5f337 100644
> --- a/tools/testing/selftests/kvm/Makefile
> +++ b/tools/testing/selftests/kvm/Makefile
> @@ -180,6 +180,7 @@ TEST_GEN_PROGS_s390x += rseq_test
> TEST_GEN_PROGS_s390x += set_memory_region_test
> TEST_GEN_PROGS_s390x += kvm_binary_stats_test
>
> +TEST_GEN_PROGS_riscv += arch_timer
> TEST_GEN_PROGS_riscv += demand_paging_test
> TEST_GEN_PROGS_riscv += dirty_log_test
> TEST_GEN_PROGS_riscv += guest_print_test
> diff --git a/tools/testing/selftests/kvm/aarch64/arch_timer.c b/tools/testing/selftests/kvm/aarch64/arch_timer.c
> index 4688b258247c..178f37737d33 100644
> --- a/tools/testing/selftests/kvm/aarch64/arch_timer.c
> +++ b/tools/testing/selftests/kvm/aarch64/arch_timer.c
> @@ -190,10 +190,14 @@ struct kvm_vm *test_vm_create(void)
> vm_init_vector_tables(vm);
> vm_install_exception_handler(vm, VECTOR_IRQ_CURRENT, guest_irq_handler);
>
> - if (!test_args.offset.reserved) {
> - if (kvm_has_cap(KVM_CAP_COUNTER_OFFSET))
> - vm_ioctl(vm, KVM_ARM_SET_COUNTER_OFFSET, &test_args.offset);
> - else
> + if (!test_args.reserved) {
> + if (kvm_has_cap(KVM_CAP_COUNTER_OFFSET)) {
> + struct kvm_arm_counter_offset offset = {
> + .counter_offset = test_args.counter_offset,
> + .reserved = 0,
> + };
> + vm_ioctl(vm, KVM_ARM_SET_COUNTER_OFFSET, &offset);
> + } else
> TEST_FAIL("no support for global offset\n");
> }
>
> diff --git a/tools/testing/selftests/kvm/arch_timer.c b/tools/testing/selftests/kvm/arch_timer.c
> index ea3dd1a772b0..184a0f5f484d 100644
> --- a/tools/testing/selftests/kvm/arch_timer.c
> +++ b/tools/testing/selftests/kvm/arch_timer.c
> @@ -33,7 +33,7 @@ struct test_args test_args = {
> .nr_iter = NR_TEST_ITERS_DEF,
> .timer_period_ms = TIMER_TEST_PERIOD_MS_DEF,
> .migration_freq_ms = TIMER_TEST_MIGRATION_FREQ_MS,
> - .offset = { .reserved = 1 },
> + .reserved = 1,
> };
>
> struct kvm_vcpu *vcpus[KVM_MAX_VCPUS];
> @@ -72,6 +72,8 @@ static void *test_vcpu_run(void *arg)
> TEST_FAIL("Unexpected guest exit\n");
> }
>
> + pr_info("PASS(vCPU-%d).\n", vcpu_idx);
> +
> return NULL;
> }
>
> @@ -186,7 +188,7 @@ static void test_print_help(char *name)
> TIMER_TEST_PERIOD_MS_DEF);
> pr_info("\t-m: Frequency (in ms) of vCPUs to migrate to different pCPU. 0 to turn off (default: %u)\n",
> TIMER_TEST_MIGRATION_FREQ_MS);
> - pr_info("\t-o: Counter offset (in counter cycles, default: 0)\n");
> + pr_info("\t-o: Counter offset (in counter cycles, default: 0)[aarch64-only]\n");
^
need
a space here
> pr_info("\t-h: print this help screen\n");
> }
>
> @@ -214,8 +216,8 @@ static bool parse_args(int argc, char *argv[])
> test_args.migration_freq_ms = atoi_non_negative("Frequency", optarg);
> break;
> case 'o':
> - test_args.offset.counter_offset = strtol(optarg, NULL, 0);
> - test_args.offset.reserved = 0;
> + test_args.counter_offset = strtol(optarg, NULL, 0);
> + test_args.reserved = 0;
> break;
> case 'h':
> default:
> diff --git a/tools/testing/selftests/kvm/include/riscv/arch_timer.h b/tools/testing/selftests/kvm/include/riscv/arch_timer.h
> new file mode 100644
> index 000000000000..5c063df13b98
> --- /dev/null
> +++ b/tools/testing/selftests/kvm/include/riscv/arch_timer.h
> @@ -0,0 +1,80 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * RISC-V Arch Timer(sstc) specific interface
> + *
> + * Copyright (c) 2023 Intel Corporation
> + */
> +
> +#ifndef SELFTEST_KVM_ARCH_TIMER_H
> +#define SELFTEST_KVM_ARCH_TIMER_H
> +
> +#include <asm/csr.h>
> +
> +static unsigned long timer_freq;
> +
> +#define msec_to_cycles(msec) \
> + ((timer_freq) * (uint64_t)(msec) / 1000)
> +
> +#define usec_to_cycles(usec) \
> + ((timer_freq) * (uint64_t)(usec) / 1000000)
> +
> +#define cycles_to_usec(cycles) \
> + ((uint64_t)(cycles) * 1000000 / (timer_freq))
> +
> +static inline uint64_t timer_get_cycles(void)
> +{
> + return csr_read(CSR_TIME);
> +}
> +
> +static inline void timer_set_cmp(uint64_t cval)
> +{
> + csr_write(CSR_STIMECMP, cval);
> +}
> +
> +static inline uint64_t timer_get_cmp(void)
> +{
> + return csr_read(CSR_STIMECMP);
> +}
> +
> +static inline void timer_irq_enable(void)
> +{
> + csr_set(CSR_SIE, IE_TIE);
> +}
> +
> +static inline void timer_irq_disable(void)
> +{
> + csr_clear(CSR_SIE, IE_TIE);
> +}
> +
> +static inline void timer_set_next_cmp_ms(uint32_t msec)
> +{
> + uint64_t now_ct = timer_get_cycles();
> + uint64_t next_ct = now_ct + msec_to_cycles(msec);
> +
> + timer_set_cmp(next_ct);
> +}
> +
> +static inline void cpu_relax(void)
> +{
> +#ifdef __riscv_zihintpause
> + asm volatile("pause" ::: "memory");
> +#else
> + /* Encoding of the pause instruction */
> + asm volatile(".4byte 0x100000F" ::: "memory");
> +#endif
> +}
cpu_relax() should go to include/riscv/processor.h
> +
> +static inline void __delay(uint64_t cycles)
> +{
> + uint64_t start = timer_get_cycles();
> +
> + while ((timer_get_cycles() - start) < cycles)
> + cpu_relax();
> +}
> +
> +static inline void udelay(unsigned long usec)
> +{
> + __delay(usec_to_cycles(usec));
> +}
> +
> +#endif /* SELFTEST_KVM_ARCH_TIMER_H */
> diff --git a/tools/testing/selftests/kvm/include/riscv/processor.h b/tools/testing/selftests/kvm/include/riscv/processor.h
> index 7d5517648ea7..268c549f87cf 100644
> --- a/tools/testing/selftests/kvm/include/riscv/processor.h
> +++ b/tools/testing/selftests/kvm/include/riscv/processor.h
> @@ -158,4 +158,14 @@ struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0,
> unsigned long arg3, unsigned long arg4,
> unsigned long arg5);
>
> +static inline void local_irq_enable(void)
> +{
> + csr_set(CSR_SSTATUS, SR_SIE);
> +}
> +
> +static inline void local_irq_disable(void)
> +{
> + csr_clear(CSR_SSTATUS, SR_SIE);
> +}
> +
> #endif /* SELFTEST_KVM_PROCESSOR_H */
> diff --git a/tools/testing/selftests/kvm/include/timer_test.h b/tools/testing/selftests/kvm/include/timer_test.h
> index 04e8aff2dc22..00b455235b82 100644
> --- a/tools/testing/selftests/kvm/include/timer_test.h
> +++ b/tools/testing/selftests/kvm/include/timer_test.h
> @@ -22,7 +22,8 @@ struct test_args {
> int nr_iter;
> int timer_period_ms;
> int migration_freq_ms;
> - struct kvm_arm_counter_offset offset;
> + uint64_t counter_offset;
> + uint64_t reserved;
These need a comment above them explaining that they are the members of
struct kvm_arm_counter_offset or they can be renamed with arm_ prefixes.
> };
>
> /* Shared variables between host and guest */
> diff --git a/tools/testing/selftests/kvm/riscv/arch_timer.c b/tools/testing/selftests/kvm/riscv/arch_timer.c
> new file mode 100644
> index 000000000000..13bf184d1ff5
> --- /dev/null
> +++ b/tools/testing/selftests/kvm/riscv/arch_timer.c
> @@ -0,0 +1,107 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * arch_timer.c - Tests the riscv64 sstc timer IRQ functionality
> + *
> + * The test validates the sstc timer IRQs using vstimecmp registers.
> + * It's ported from the aarch64 arch_timer test.
> + *
> + * Copyright (c) 2023, Intel Corporation.
> + */
> +
> +#define _GNU_SOURCE
> +
> +#include "arch_timer.h"
> +#include "kvm_util.h"
> +#include "processor.h"
> +#include "timer_test.h"
> +
> +static int timer_irq = IRQ_S_TIMER;
> +
> +static void guest_irq_handler(struct ex_regs *regs)
> +{
> + uint64_t xcnt, xcnt_diff_us, cmp;
> + unsigned int intid = regs->cause & ~CAUSE_IRQ_FLAG;
> + uint32_t cpu = guest_get_vcpuid();
> + struct test_vcpu_shared_data *shared_data = &vcpu_shared_data[cpu];
> +
> + timer_irq_disable();
> +
> + xcnt = timer_get_cycles();
> + cmp = timer_get_cmp();
> + xcnt_diff_us = cycles_to_usec(xcnt - shared_data->xcnt);
> +
> + /* Make sure we are dealing with the correct timer IRQ */
> + GUEST_ASSERT_EQ(intid, timer_irq);
> +
> + __GUEST_ASSERT(xcnt >= cmp,
> + "xcnt = 0x%llx, cmp = 0x%llx, xcnt_diff_us = 0x%llx",
> + xcnt, cmp, xcnt_diff_us);
> +
> + WRITE_ONCE(shared_data->nr_iter, shared_data->nr_iter + 1);
> +}
> +
> +static void guest_run(struct test_vcpu_shared_data *shared_data)
> +{
> + uint32_t irq_iter, config_iter;
> +
> + shared_data->nr_iter = 0;
> + shared_data->guest_stage = 0;
> +
> + for (config_iter = 0; config_iter < test_args.nr_iter; config_iter++) {
> + /* Setup the next interrupt */
> + timer_set_next_cmp_ms(test_args.timer_period_ms);
> + shared_data->xcnt = timer_get_cycles();
> + timer_irq_enable();
> +
> + /* Setup a timeout for the interrupt to arrive */
> + udelay(msecs_to_usecs(test_args.timer_period_ms) +
> + TIMER_TEST_ERR_MARGIN_US);
> +
> + irq_iter = READ_ONCE(shared_data->nr_iter);
> + GUEST_ASSERT_EQ(config_iter + 1, irq_iter);
> + }
> +}
> +
> +static void guest_code(void)
> +{
> + uint32_t cpu = guest_get_vcpuid();
> + struct test_vcpu_shared_data *shared_data = &vcpu_shared_data[cpu];
> +
> + timer_irq_disable();
> + local_irq_enable();
> +
> + guest_run(shared_data);
> +
> + GUEST_DONE();
> +}
> +
> +struct kvm_vm *test_vm_create(void)
> +{
> + struct kvm_vm *vm;
> + int nr_vcpus = test_args.nr_vcpus;
> +
> + vm = vm_create_with_vcpus(nr_vcpus, guest_code, vcpus);
> + __TEST_REQUIRE(__vcpu_has_ext(vcpus[0], KVM_RISCV_ISA_EXT_SSTC),
> + "SSTC not available, skipping test\n");
> +
> + vm_init_vector_tables(vm);
> + vm_install_interrupt_handler(vm, guest_irq_handler);
> +
> + for (int i = 0; i < nr_vcpus; i++)
> + vcpu_init_vector_tables(vcpus[i]);
> +
> + /* Initialize guest timer frequency. */
> + vcpu_get_reg(vcpus[0], RISCV_TIMER_REG(frequency), &timer_freq);
> + sync_global_to_guest(vm, timer_freq);
> + pr_debug("timer_freq: %lu\n", timer_freq);
> +
> + /* Make all the test's cmdline args visible to the guest */
> + sync_global_to_guest(vm, test_args);
> +
> + return vm;
> +}
> +
> +void test_vm_cleanup(struct kvm_vm *vm)
> +{
> + kvm_vm_free(vm);
> +}
> --
> 2.34.1
>
Besides the three minor comments, this looks good to me.
Reviewed-by: Andrew Jones <ajones@xxxxxxxxxxxxxxxx>
Thanks,
drew
