| Message ID | 20241021062226.108657-3-manali.shukla@amd.com |
|---|---|
| State | New |
| Headers | show |
| Series | KVM selftests enhancements | expand |
On Mon, Oct 21, 2024, Manali Shukla wrote: > From: Manali Shukla <Manali.Shukla@amd.com> > > The interface is used to read the data values of a specified vcpu stat > from the currenly available binary stats interface. > > Add a concatenation trickery to trigger compiler error if the stat > doesn't exist, so that it is not possible to pass a per-VM stat into > vcpu_get_stat(). > > Suggested-by: Sean Christopherson <seanjc@google.com> > Signed-off-by: Manali Shukla <Manali.Shukla@amd.com> > --- > .../testing/selftests/kvm/include/kvm_util.h | 52 +++++++++++++++++++ > .../kvm/include/x86_64/kvm_util_arch.h | 36 +++++++++++++ > tools/testing/selftests/kvm/lib/kvm_util.c | 40 ++++++++++++++ > 3 files changed, 128 insertions(+) > > diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h > index bc7c242480d6..5dd3acf174f8 100644 > --- a/tools/testing/selftests/kvm/include/kvm_util.h > +++ b/tools/testing/selftests/kvm/include/kvm_util.h > @@ -531,6 +531,14 @@ void read_stat_data(int stats_fd, struct kvm_stats_header *header, > struct kvm_stats_desc *desc, uint64_t *data, > size_t max_elements); > > +#define DEFINE_CHECK_STAT(type, stat) \ > +static inline int check_##type##_##stat##_exists(void) \ > +{ \ > + return 1; \ > +} \ > + > +#define STAT_EXISTS(type, stat) (check_##type##_##stat##_exists()) This is all unnecessary complicated. To trigger a compilation error, the set of knnown stats just needs to be defined as _something_ and then referenced. There's no need for layers of macros and a function for each stat. The fact that a stat is defined is proof of its existence. > + > void __vm_get_stat(struct kvm_vm *vm, const char *stat_name, uint64_t *data, > size_t max_elements); > > @@ -542,6 +550,50 @@ static inline uint64_t vm_get_stat(struct kvm_vm *vm, const char *stat_name) > return data; > } > > +#define DEFINE_GENERIC_VCPU_STAT \ > + DEFINE_CHECK_STAT(vcpu, halt_successfull_poll) \ > + DEFINE_CHECK_STAT(vcpu, halt_attempted_poll) \ > + DEFINE_CHECK_STAT(vcpu, halt_poll_invalid) \ > + DEFINE_CHECK_STAT(vcpu, halt_wakeup) \ > + DEFINE_CHECK_STAT(vcpu, halt_poll_success_ns) \ > + DEFINE_CHECK_STAT(vcpu, halt_poll_fail_ns) \ > + DEFINE_CHECK_STAT(vcpu, halt_wait_ns) \ > + DEFINE_CHECK_STAT(vcpu, halt_poll_success_hist) \ > + DEFINE_CHECK_STAT(vcpu, halt_poll_fail_hist) \ > + DEFINE_CHECK_STAT(vcpu, halt_wait_hist) \ > + DEFINE_CHECK_STAT(vcpu, blocking) \ > + > +/* > + * Define a default empty macro for architectures which do not specify > + * arch specific vcpu stats > + */ > + > +#ifndef DEFINE_ARCH_VCPU_STAT > +#define DEFINE_ARCH_VCPU_STAT > +#endif > + > +DEFINE_GENERIC_VCPU_STAT There's also no need to define macros in arch code just to expand them in common code. Add simple macros in kvm_util_types.h and this goes away. > +DEFINE_ARCH_VCPU_STAT > + > +#undef DEFINE_CHECK_STAT > +#undef DEFINE_GENERIC_VCPU_STAT > +#undef DEFINE_ARCH_VCPU_STAT > +void __vcpu_get_stat(struct kvm_vcpu *vcpu, const char *stat_name, uint64_t *data, > + size_t max_elements); > + > +#define vcpu_get_stat(vcpu, stat_name) \ > +({ \ > + uint64_t data; \ > + \ > + STAT_EXISTS(vcpu, stat_name); \ > + __vcpu_get_stat(vcpu, #stat_name, &data, 1); \ > + data; \ > +}) \ > + > +#undef DEFINE_CHECK_STAT > +#undef DEFINE_GENERIC_VCPU_STAT > + ... > +void __vcpu_get_stat(struct kvm_vcpu *vcpu, const char *stat_name, uint64_t *data, > + size_t max_elements) > +{ > + int vcpu_stats_fd; > + struct kvm_stats_header header; > + struct kvm_stats_desc *desc, *t_desc; > + size_t size_desc; > + int i; > + > + vcpu_stats_fd = vcpu_get_stats_fd(vcpu); > + read_stats_header(vcpu_stats_fd, &header); > + > + desc = read_stats_descriptors(vcpu_stats_fd, &header); > + size_desc = get_stats_descriptor_size(&header); > + > + for (i = 0; i < header.num_desc; ++i) { > + t_desc = (void *)desc + (i * size_desc); > + > + if (strcmp(t_desc->name, stat_name)) > + continue; > + > + read_stat_data(vcpu_stats_fd, &header, t_desc, > + data, max_elements); > + break; > + } > +} This is copy-pasted nearly verbatim from the VM-scoped code. It even has the same bugs (doesn't assert the stat exists), along with new bugs (leaks the fd and header). It takes a bit of work, but not _that_ much work, to genericize the VM-scoped infrastructure and reuse it for vCPU-scoped stats.
diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h index bc7c242480d6..5dd3acf174f8 100644 --- a/tools/testing/selftests/kvm/include/kvm_util.h +++ b/tools/testing/selftests/kvm/include/kvm_util.h @@ -531,6 +531,14 @@ void read_stat_data(int stats_fd, struct kvm_stats_header *header, struct kvm_stats_desc *desc, uint64_t *data, size_t max_elements); +#define DEFINE_CHECK_STAT(type, stat) \ +static inline int check_##type##_##stat##_exists(void) \ +{ \ + return 1; \ +} \ + +#define STAT_EXISTS(type, stat) (check_##type##_##stat##_exists()) + void __vm_get_stat(struct kvm_vm *vm, const char *stat_name, uint64_t *data, size_t max_elements); @@ -542,6 +550,50 @@ static inline uint64_t vm_get_stat(struct kvm_vm *vm, const char *stat_name) return data; } +#define DEFINE_GENERIC_VCPU_STAT \ + DEFINE_CHECK_STAT(vcpu, halt_successfull_poll) \ + DEFINE_CHECK_STAT(vcpu, halt_attempted_poll) \ + DEFINE_CHECK_STAT(vcpu, halt_poll_invalid) \ + DEFINE_CHECK_STAT(vcpu, halt_wakeup) \ + DEFINE_CHECK_STAT(vcpu, halt_poll_success_ns) \ + DEFINE_CHECK_STAT(vcpu, halt_poll_fail_ns) \ + DEFINE_CHECK_STAT(vcpu, halt_wait_ns) \ + DEFINE_CHECK_STAT(vcpu, halt_poll_success_hist) \ + DEFINE_CHECK_STAT(vcpu, halt_poll_fail_hist) \ + DEFINE_CHECK_STAT(vcpu, halt_wait_hist) \ + DEFINE_CHECK_STAT(vcpu, blocking) \ + +/* + * Define a default empty macro for architectures which do not specify + * arch specific vcpu stats + */ + +#ifndef DEFINE_ARCH_VCPU_STAT +#define DEFINE_ARCH_VCPU_STAT +#endif + +DEFINE_GENERIC_VCPU_STAT +DEFINE_ARCH_VCPU_STAT + +#undef DEFINE_CHECK_STAT +#undef DEFINE_GENERIC_VCPU_STAT +#undef DEFINE_ARCH_VCPU_STAT + +void __vcpu_get_stat(struct kvm_vcpu *vcpu, const char *stat_name, uint64_t *data, + size_t max_elements); + +#define vcpu_get_stat(vcpu, stat_name) \ +({ \ + uint64_t data; \ + \ + STAT_EXISTS(vcpu, stat_name); \ + __vcpu_get_stat(vcpu, #stat_name, &data, 1); \ + data; \ +}) \ + +#undef DEFINE_CHECK_STAT +#undef DEFINE_GENERIC_VCPU_STAT + void vm_create_irqchip(struct kvm_vm *vm); static inline int __vm_create_guest_memfd(struct kvm_vm *vm, uint64_t size, diff --git a/tools/testing/selftests/kvm/include/x86_64/kvm_util_arch.h b/tools/testing/selftests/kvm/include/x86_64/kvm_util_arch.h index 972bb1c4ab4c..3cdc3c856ed2 100644 --- a/tools/testing/selftests/kvm/include/x86_64/kvm_util_arch.h +++ b/tools/testing/selftests/kvm/include/x86_64/kvm_util_arch.h @@ -48,4 +48,40 @@ do { \ } \ } while (0) +#define DEFINE_ARCH_VCPU_STAT \ + DEFINE_CHECK_STAT(vcpu, pf_taken) \ + DEFINE_CHECK_STAT(vcpu, pf_fixed) \ + DEFINE_CHECK_STAT(vcpu, pf_emulate) \ + DEFINE_CHECK_STAT(vcpu, pf_spurious) \ + DEFINE_CHECK_STAT(vcpu, pf_fast) \ + DEFINE_CHECK_STAT(vcpu, pf_mmio_spte_created) \ + DEFINE_CHECK_STAT(vcpu, pf_guest) \ + DEFINE_CHECK_STAT(vcpu, tlb_flush) \ + DEFINE_CHECK_STAT(vcpu, invlpg) \ + DEFINE_CHECK_STAT(vcpu, exits) \ + DEFINE_CHECK_STAT(vcpu, io_exits) \ + DEFINE_CHECK_STAT(vcpu, mmio_exits) \ + DEFINE_CHECK_STAT(vcpu, signal_exits) \ + DEFINE_CHECK_STAT(vcpu, irq_window_exits) \ + DEFINE_CHECK_STAT(vcpu, nmi_window_exits) \ + DEFINE_CHECK_STAT(vcpu, l1d_flush) \ + DEFINE_CHECK_STAT(vcpu, halt_exits) \ + DEFINE_CHECK_STAT(vcpu, request_irq_exits) \ + DEFINE_CHECK_STAT(vcpu, irq_exits) \ + DEFINE_CHECK_STAT(vcpu, host_state_reload) \ + DEFINE_CHECK_STAT(vcpu, fpu_reload) \ + DEFINE_CHECK_STAT(vcpu, insn_emulation) \ + DEFINE_CHECK_STAT(vcpu, insn_emulation_fail) \ + DEFINE_CHECK_STAT(vcpu, hypercalls) \ + DEFINE_CHECK_STAT(vcpu, irq_injections) \ + DEFINE_CHECK_STAT(vcpu, nmi_injections) \ + DEFINE_CHECK_STAT(vcpu, req_event) \ + DEFINE_CHECK_STAT(vcpu, nested_run) \ + DEFINE_CHECK_STAT(vcpu, directed_yield_attempted) \ + DEFINE_CHECK_STAT(vcpu, directed_yield_successful) \ + DEFINE_CHECK_STAT(vcpu, preemption_reported) \ + DEFINE_CHECK_STAT(vcpu, preemption_other) \ + DEFINE_CHECK_STAT(vcpu, guest_mode) \ + DEFINE_CHECK_STAT(vcpu, notify_window_exits) \ + #endif // SELFTEST_KVM_UTIL_ARCH_H diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c index a2b7df5f1d39..3ee84e117a04 100644 --- a/tools/testing/selftests/kvm/lib/kvm_util.c +++ b/tools/testing/selftests/kvm/lib/kvm_util.c @@ -2195,6 +2195,46 @@ void read_stat_data(int stats_fd, struct kvm_stats_header *header, desc->name, size, ret); } +/* + * Read the data of the named vcpu stat + * + * Input Args: + * vcpu - the vcpu for which the stat should be read + * stat_name - the name of the stat to read + * max_elements - the maximum number of 8-byte values to read into data + * + * Output Args: + * data - the buffer into which stat data should be read + * + * Read the data values of a specified stat from the binary stats interface. + */ +void __vcpu_get_stat(struct kvm_vcpu *vcpu, const char *stat_name, uint64_t *data, + size_t max_elements) +{ + int vcpu_stats_fd; + struct kvm_stats_header header; + struct kvm_stats_desc *desc, *t_desc; + size_t size_desc; + int i; + + vcpu_stats_fd = vcpu_get_stats_fd(vcpu); + read_stats_header(vcpu_stats_fd, &header); + + desc = read_stats_descriptors(vcpu_stats_fd, &header); + size_desc = get_stats_descriptor_size(&header); + + for (i = 0; i < header.num_desc; ++i) { + t_desc = (void *)desc + (i * size_desc); + + if (strcmp(t_desc->name, stat_name)) + continue; + + read_stat_data(vcpu_stats_fd, &header, t_desc, + data, max_elements); + break; + } +} + /* * Read the data of the named stat *