From acf064345018853ab2fc86a5637891d605ea60c8 Mon Sep 17 00:00:00 2001 From: "Pratik R. Sampat" Date: Wed, 5 Mar 2025 16:59:54 -0600 Subject: KVM: selftests: Add SMT control state helper Move the SMT control check out of the hyperv_cpuid selftest so that it is generally accessible all KVM selftests. Split the functionality into a helper that populates a buffer with SMT control value which other helpers can use to ascertain if SMT state is available and active. Signed-off-by: Pratik R. Sampat Link: https://lore.kernel.org/r/20250305230000.231025-5-prsampat@amd.com [sean: prepend is_ to the helpers] Signed-off-by: Sean Christopherson --- tools/testing/selftests/kvm/include/kvm_util.h | 35 ++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) (limited to 'tools/testing/selftests/kvm/include/kvm_util.h') diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h index 373912464fb4..a1fc52bbdf7a 100644 --- a/tools/testing/selftests/kvm/include/kvm_util.h +++ b/tools/testing/selftests/kvm/include/kvm_util.h @@ -549,6 +549,41 @@ void kvm_get_stat(struct kvm_binary_stats *stats, const char *name, #define vm_get_stat(vm, stat) __get_stat(&(vm)->stats, stat) #define vcpu_get_stat(vcpu, stat) __get_stat(&(vcpu)->stats, stat) +static inline bool read_smt_control(char *buf, size_t buf_size) +{ + FILE *f = fopen("/sys/devices/system/cpu/smt/control", "r"); + bool ret; + + if (!f) + return false; + + ret = fread(buf, sizeof(*buf), buf_size, f) > 0; + fclose(f); + + return ret; +} + +static inline bool is_smt_possible(void) +{ + char buf[16]; + + if (read_smt_control(buf, sizeof(buf)) && + (!strncmp(buf, "forceoff", 8) || !strncmp(buf, "notsupported", 12))) + return false; + + return true; +} + +static inline bool is_smt_on(void) +{ + char buf[16]; + + if (read_smt_control(buf, sizeof(buf)) && !strncmp(buf, "on", 2)) + return true; + + return false; +} + void vm_create_irqchip(struct kvm_vm *vm); static inline int __vm_create_guest_memfd(struct kvm_vm *vm, uint64_t size, -- cgit v1.2.3