| Message ID | 20241222140247.174998-5-vaibhav@linux.ibm.com |
|---|---|
| State | New |
| Headers | show |
| Series | kvm powerpc/book3s-hv: Expose Hostwide counters as perf-events | expand |
On Sun, Dec 22, 2024 at 07:32:32PM +0530, Vaibhav Jain wrote: > Introduce a new PMU named 'kvm-hv' to report Book3s kvm-hv specific > performance counters. This will expose KVM-HV specific performance > attributes to user-space via kernel's PMU infrastructure and would enable > users to monitor active kvm-hv based guests. > > The patch creates necessary scaffolding to for the new PMU callbacks and > introduces two new exports kvmppc_{,un}register_pmu() that are called from > kvm-hv init and exit function to perform initialize and cleanup for the > 'kvm-hv' PMU. The patch doesn't introduce any perf-events yet, which will > be introduced in later patches > > Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com> > --- > arch/powerpc/include/asm/kvm_book3s.h | 12 +++ > arch/powerpc/kvm/Makefile | 6 ++ > arch/powerpc/kvm/book3s_hv.c | 7 ++ > arch/powerpc/kvm/book3s_hv_pmu.c | 133 ++++++++++++++++++++++++++ > 4 files changed, 158 insertions(+) > create mode 100644 arch/powerpc/kvm/book3s_hv_pmu.c > > diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h > index e1ff291ba891..cf91a1493159 100644 > --- a/arch/powerpc/include/asm/kvm_book3s.h > +++ b/arch/powerpc/include/asm/kvm_book3s.h > @@ -334,6 +334,9 @@ static inline bool kvmhv_is_nestedv1(void) > return !static_branch_likely(&__kvmhv_is_nestedv2); > } > > +int kvmppc_register_pmu(void); > +void kvmppc_unregister_pmu(void); > + > #else > > static inline bool kvmhv_is_nestedv2(void) > @@ -346,6 +349,15 @@ static inline bool kvmhv_is_nestedv1(void) > return false; > } > > +static int kvmppc_register_pmu(void) > +{ > + return 0; > +} > + > +static void kvmppc_unregister_pmu(void) > +{ > +} > + > #endif > > int __kvmhv_nestedv2_reload_ptregs(struct kvm_vcpu *vcpu, struct pt_regs *regs); > diff --git a/arch/powerpc/kvm/Makefile b/arch/powerpc/kvm/Makefile > index 4bd9d1230869..094c3916d9d0 100644 > --- a/arch/powerpc/kvm/Makefile > +++ b/arch/powerpc/kvm/Makefile > @@ -92,6 +92,12 @@ kvm-book3s_64-builtin-objs-$(CONFIG_KVM_BOOK3S_64_HANDLER) += \ > $(kvm-book3s_64-builtin-tm-objs-y) \ > $(kvm-book3s_64-builtin-xics-objs-y) > > +# enable kvm_hv perf events > +ifdef CONFIG_HAVE_PERF_EVENTS > +kvm-book3s_64-builtin-objs-$(CONFIG_KVM_BOOK3S_64_HANDLER) += \ > + book3s_hv_pmu.o > +endif > + > obj-$(CONFIG_GUEST_STATE_BUFFER_TEST) += test-guest-state-buffer.o > endif > > diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c > index 25429905ae90..83bcce2fb557 100644 > --- a/arch/powerpc/kvm/book3s_hv.c > +++ b/arch/powerpc/kvm/book3s_hv.c > @@ -6662,6 +6662,12 @@ static int kvmppc_book3s_init_hv(void) > return r; > } > > + r = kvmppc_register_pmu(); > + if (r) { > + pr_err("KVM-HV: Unable to register PMUs %d\n", r); > + goto err; > + } > + > kvm_ops_hv.owner = THIS_MODULE; > kvmppc_hv_ops = &kvm_ops_hv; > > @@ -6676,6 +6682,7 @@ static int kvmppc_book3s_init_hv(void) > > static void kvmppc_book3s_exit_hv(void) > { > + kvmppc_unregister_pmu(); > kvmppc_uvmem_free(); > kvmppc_free_host_rm_ops(); > if (kvmppc_radix_possible()) > diff --git a/arch/powerpc/kvm/book3s_hv_pmu.c b/arch/powerpc/kvm/book3s_hv_pmu.c > new file mode 100644 > index 000000000000..e72542d5e750 > --- /dev/null > +++ b/arch/powerpc/kvm/book3s_hv_pmu.c > @@ -0,0 +1,133 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Description: PMUs specific to running nested KVM-HV guests > + * on Book3S processors (specifically POWER9 and later). > + */ > + > +#define pr_fmt(fmt) "kvmppc-pmu: " fmt > + > +#include "asm-generic/local64.h" > +#include <linux/kernel.h> > +#include <linux/errno.h> > +#include <linux/ratelimit.h> > +#include <linux/kvm_host.h> > +#include <linux/gfp_types.h> > +#include <linux/pgtable.h> > +#include <linux/perf_event.h> > +#include <linux/spinlock_types.h> > +#include <linux/spinlock.h> > + > +#include <asm/types.h> > +#include <asm/kvm_ppc.h> > +#include <asm/kvm_book3s.h> > +#include <asm/mmu.h> > +#include <asm/pgalloc.h> > +#include <asm/pte-walk.h> > +#include <asm/reg.h> > +#include <asm/plpar_wrappers.h> > +#include <asm/firmware.h> > + > +enum kvmppc_pmu_eventid { > + KVMPPC_EVENT_MAX, > +}; > + > +static struct attribute *kvmppc_pmu_events_attr[] = { > + NULL, > +}; > + > +static const struct attribute_group kvmppc_pmu_events_group = { > + .name = "events", > + .attrs = kvmppc_pmu_events_attr, > +}; > + > +PMU_FORMAT_ATTR(event, "config:0"); > +static struct attribute *kvmppc_pmu_format_attr[] = { > + &format_attr_event.attr, > + NULL, > +}; > + > +static struct attribute_group kvmppc_pmu_format_group = { > + .name = "format", > + .attrs = kvmppc_pmu_format_attr, > +}; > + > +static const struct attribute_group *kvmppc_pmu_attr_groups[] = { > + &kvmppc_pmu_events_group, > + &kvmppc_pmu_format_group, > + NULL, > +}; > + > +static int kvmppc_pmu_event_init(struct perf_event *event) > +{ > + unsigned int config = event->attr.config; > + > + pr_debug("%s: Event(%p) id=%llu cpu=%x on_cpu=%x config=%u", > + __func__, event, event->id, event->cpu, > + event->oncpu, config); > + > + if (event->attr.type != event->pmu->type) > + return -ENOENT; > + > + if (config >= KVMPPC_EVENT_MAX) > + return -EINVAL; > + > + local64_set(&event->hw.prev_count, 0); > + local64_set(&event->count, 0); > + > + return 0; > +} > + > +static void kvmppc_pmu_del(struct perf_event *event, int flags) > +{ > +} > + > +static int kvmppc_pmu_add(struct perf_event *event, int flags) > +{ > + return 0; > +} > + > +static void kvmppc_pmu_read(struct perf_event *event) > +{ > +} > + > +/* L1 wide counters PMU */ > +static struct pmu kvmppc_pmu = { > + .task_ctx_nr = perf_sw_context, > + .name = "kvm-hv", > + .event_init = kvmppc_pmu_event_init, > + .add = kvmppc_pmu_add, > + .del = kvmppc_pmu_del, > + .read = kvmppc_pmu_read, > + .attr_groups = kvmppc_pmu_attr_groups, > + .type = -1, > +}; > + > +int kvmppc_register_pmu(void) > +{ > + int rc = -EOPNOTSUPP; > + > + /* only support events for nestedv2 right now */ > + if (kvmhv_is_nestedv2()) { > + /* Setup done now register the PMU */ > + pr_info("Registering kvm-hv pmu"); > + > + /* Register only if we arent already registyered */ > + rc = (kvmppc_pmu.type == -1) ? > + perf_pmu_register(&kvmppc_pmu, kvmppc_pmu.name, > + -1) : 0; > + } > + > + return rc; > +} > +EXPORT_SYMBOL_GPL(kvmppc_register_pmu); This logic breaks on bare metal. kvmppc_register_pmu() returns -EOPNOTSUPP because of which kvm_hv cannot be loaded. > + > +void kvmppc_unregister_pmu(void) > +{ > + if (kvmhv_is_nestedv2()) { > + if (kvmppc_pmu.type != -1) > + perf_pmu_unregister(&kvmppc_pmu); > + > + pr_info("kvmhv_pmu unregistered.\n"); > + } > +} > +EXPORT_SYMBOL_GPL(kvmppc_unregister_pmu); > -- > 2.47.1 >
Hi Gautam, Thanks for reviewing this patch. My responses to your review comments inline below: Gautam Menghani <gautam@linux.ibm.com> writes: > On Sun, Dec 22, 2024 at 07:32:32PM +0530, Vaibhav Jain wrote: >> Introduce a new PMU named 'kvm-hv' to report Book3s kvm-hv specific >> performance counters. This will expose KVM-HV specific performance >> attributes to user-space via kernel's PMU infrastructure and would enable >> users to monitor active kvm-hv based guests. >> >> The patch creates necessary scaffolding to for the new PMU callbacks and >> introduces two new exports kvmppc_{,un}register_pmu() that are called from >> kvm-hv init and exit function to perform initialize and cleanup for the >> 'kvm-hv' PMU. The patch doesn't introduce any perf-events yet, which will >> be introduced in later patches >> >> Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com> >> --- >> arch/powerpc/include/asm/kvm_book3s.h | 12 +++ >> arch/powerpc/kvm/Makefile | 6 ++ >> arch/powerpc/kvm/book3s_hv.c | 7 ++ >> arch/powerpc/kvm/book3s_hv_pmu.c | 133 ++++++++++++++++++++++++++ >> 4 files changed, 158 insertions(+) >> create mode 100644 arch/powerpc/kvm/book3s_hv_pmu.c >> >> diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h >> index e1ff291ba891..cf91a1493159 100644 >> --- a/arch/powerpc/include/asm/kvm_book3s.h >> +++ b/arch/powerpc/include/asm/kvm_book3s.h >> @@ -334,6 +334,9 @@ static inline bool kvmhv_is_nestedv1(void) >> return !static_branch_likely(&__kvmhv_is_nestedv2); >> } >> >> +int kvmppc_register_pmu(void); >> +void kvmppc_unregister_pmu(void); >> + >> #else >> >> static inline bool kvmhv_is_nestedv2(void) >> @@ -346,6 +349,15 @@ static inline bool kvmhv_is_nestedv1(void) >> return false; >> } >> >> +static int kvmppc_register_pmu(void) >> +{ >> + return 0; >> +} >> + >> +static void kvmppc_unregister_pmu(void) >> +{ >> +} >> + >> #endif >> >> int __kvmhv_nestedv2_reload_ptregs(struct kvm_vcpu *vcpu, struct pt_regs *regs); >> diff --git a/arch/powerpc/kvm/Makefile b/arch/powerpc/kvm/Makefile >> index 4bd9d1230869..094c3916d9d0 100644 >> --- a/arch/powerpc/kvm/Makefile >> +++ b/arch/powerpc/kvm/Makefile >> @@ -92,6 +92,12 @@ kvm-book3s_64-builtin-objs-$(CONFIG_KVM_BOOK3S_64_HANDLER) += \ >> $(kvm-book3s_64-builtin-tm-objs-y) \ >> $(kvm-book3s_64-builtin-xics-objs-y) >> >> +# enable kvm_hv perf events >> +ifdef CONFIG_HAVE_PERF_EVENTS >> +kvm-book3s_64-builtin-objs-$(CONFIG_KVM_BOOK3S_64_HANDLER) += \ >> + book3s_hv_pmu.o >> +endif >> + >> obj-$(CONFIG_GUEST_STATE_BUFFER_TEST) += test-guest-state-buffer.o >> endif >> >> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c >> index 25429905ae90..83bcce2fb557 100644 >> --- a/arch/powerpc/kvm/book3s_hv.c >> +++ b/arch/powerpc/kvm/book3s_hv.c >> @@ -6662,6 +6662,12 @@ static int kvmppc_book3s_init_hv(void) >> return r; >> } >> >> + r = kvmppc_register_pmu(); >> + if (r) { >> + pr_err("KVM-HV: Unable to register PMUs %d\n", r); >> + goto err; >> + } >> + >> kvm_ops_hv.owner = THIS_MODULE; >> kvmppc_hv_ops = &kvm_ops_hv; >> >> @@ -6676,6 +6682,7 @@ static int kvmppc_book3s_init_hv(void) >> >> static void kvmppc_book3s_exit_hv(void) >> { >> + kvmppc_unregister_pmu(); >> kvmppc_uvmem_free(); >> kvmppc_free_host_rm_ops(); >> if (kvmppc_radix_possible()) >> diff --git a/arch/powerpc/kvm/book3s_hv_pmu.c b/arch/powerpc/kvm/book3s_hv_pmu.c >> new file mode 100644 >> index 000000000000..e72542d5e750 >> --- /dev/null >> +++ b/arch/powerpc/kvm/book3s_hv_pmu.c >> @@ -0,0 +1,133 @@ >> +// SPDX-License-Identifier: GPL-2.0 >> +/* >> + * Description: PMUs specific to running nested KVM-HV guests >> + * on Book3S processors (specifically POWER9 and later). >> + */ >> + >> +#define pr_fmt(fmt) "kvmppc-pmu: " fmt >> + >> +#include "asm-generic/local64.h" >> +#include <linux/kernel.h> >> +#include <linux/errno.h> >> +#include <linux/ratelimit.h> >> +#include <linux/kvm_host.h> >> +#include <linux/gfp_types.h> >> +#include <linux/pgtable.h> >> +#include <linux/perf_event.h> >> +#include <linux/spinlock_types.h> >> +#include <linux/spinlock.h> >> + >> +#include <asm/types.h> >> +#include <asm/kvm_ppc.h> >> +#include <asm/kvm_book3s.h> >> +#include <asm/mmu.h> >> +#include <asm/pgalloc.h> >> +#include <asm/pte-walk.h> >> +#include <asm/reg.h> >> +#include <asm/plpar_wrappers.h> >> +#include <asm/firmware.h> >> + >> +enum kvmppc_pmu_eventid { >> + KVMPPC_EVENT_MAX, >> +}; >> + >> +static struct attribute *kvmppc_pmu_events_attr[] = { >> + NULL, >> +}; >> + >> +static const struct attribute_group kvmppc_pmu_events_group = { >> + .name = "events", >> + .attrs = kvmppc_pmu_events_attr, >> +}; >> + >> +PMU_FORMAT_ATTR(event, "config:0"); >> +static struct attribute *kvmppc_pmu_format_attr[] = { >> + &format_attr_event.attr, >> + NULL, >> +}; >> + >> +static struct attribute_group kvmppc_pmu_format_group = { >> + .name = "format", >> + .attrs = kvmppc_pmu_format_attr, >> +}; >> + >> +static const struct attribute_group *kvmppc_pmu_attr_groups[] = { >> + &kvmppc_pmu_events_group, >> + &kvmppc_pmu_format_group, >> + NULL, >> +}; >> + >> +static int kvmppc_pmu_event_init(struct perf_event *event) >> +{ >> + unsigned int config = event->attr.config; >> + >> + pr_debug("%s: Event(%p) id=%llu cpu=%x on_cpu=%x config=%u", >> + __func__, event, event->id, event->cpu, >> + event->oncpu, config); >> + >> + if (event->attr.type != event->pmu->type) >> + return -ENOENT; >> + >> + if (config >= KVMPPC_EVENT_MAX) >> + return -EINVAL; >> + >> + local64_set(&event->hw.prev_count, 0); >> + local64_set(&event->count, 0); >> + >> + return 0; >> +} >> + >> +static void kvmppc_pmu_del(struct perf_event *event, int flags) >> +{ >> +} >> + >> +static int kvmppc_pmu_add(struct perf_event *event, int flags) >> +{ >> + return 0; >> +} >> + >> +static void kvmppc_pmu_read(struct perf_event *event) >> +{ >> +} >> + >> +/* L1 wide counters PMU */ >> +static struct pmu kvmppc_pmu = { >> + .task_ctx_nr = perf_sw_context, >> + .name = "kvm-hv", >> + .event_init = kvmppc_pmu_event_init, >> + .add = kvmppc_pmu_add, >> + .del = kvmppc_pmu_del, >> + .read = kvmppc_pmu_read, >> + .attr_groups = kvmppc_pmu_attr_groups, >> + .type = -1, >> +}; >> + >> +int kvmppc_register_pmu(void) >> +{ >> + int rc = -EOPNOTSUPP; >> + >> + /* only support events for nestedv2 right now */ >> + if (kvmhv_is_nestedv2()) { >> + /* Setup done now register the PMU */ >> + pr_info("Registering kvm-hv pmu"); >> + >> + /* Register only if we arent already registyered */ >> + rc = (kvmppc_pmu.type == -1) ? >> + perf_pmu_register(&kvmppc_pmu, kvmppc_pmu.name, >> + -1) : 0; >> + } >> + >> + return rc; >> +} >> +EXPORT_SYMBOL_GPL(kvmppc_register_pmu); > > This logic breaks on bare metal. kvmppc_register_pmu() returns > -EOPNOTSUPP because of which kvm_hv cannot be loaded. > Good catch. Fixing this in v2 >> + >> +void kvmppc_unregister_pmu(void) >> +{ >> + if (kvmhv_is_nestedv2()) { >> + if (kvmppc_pmu.type != -1) >> + perf_pmu_unregister(&kvmppc_pmu); >> + >> + pr_info("kvmhv_pmu unregistered.\n"); >> + } >> +} >> +EXPORT_SYMBOL_GPL(kvmppc_unregister_pmu); >> -- >> 2.47.1 >>
diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h index e1ff291ba891..cf91a1493159 100644 --- a/arch/powerpc/include/asm/kvm_book3s.h +++ b/arch/powerpc/include/asm/kvm_book3s.h @@ -334,6 +334,9 @@ static inline bool kvmhv_is_nestedv1(void) return !static_branch_likely(&__kvmhv_is_nestedv2); } +int kvmppc_register_pmu(void); +void kvmppc_unregister_pmu(void); + #else static inline bool kvmhv_is_nestedv2(void) @@ -346,6 +349,15 @@ static inline bool kvmhv_is_nestedv1(void) return false; } +static int kvmppc_register_pmu(void) +{ + return 0; +} + +static void kvmppc_unregister_pmu(void) +{ +} + #endif int __kvmhv_nestedv2_reload_ptregs(struct kvm_vcpu *vcpu, struct pt_regs *regs); diff --git a/arch/powerpc/kvm/Makefile b/arch/powerpc/kvm/Makefile index 4bd9d1230869..094c3916d9d0 100644 --- a/arch/powerpc/kvm/Makefile +++ b/arch/powerpc/kvm/Makefile @@ -92,6 +92,12 @@ kvm-book3s_64-builtin-objs-$(CONFIG_KVM_BOOK3S_64_HANDLER) += \ $(kvm-book3s_64-builtin-tm-objs-y) \ $(kvm-book3s_64-builtin-xics-objs-y) +# enable kvm_hv perf events +ifdef CONFIG_HAVE_PERF_EVENTS +kvm-book3s_64-builtin-objs-$(CONFIG_KVM_BOOK3S_64_HANDLER) += \ + book3s_hv_pmu.o +endif + obj-$(CONFIG_GUEST_STATE_BUFFER_TEST) += test-guest-state-buffer.o endif diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 25429905ae90..83bcce2fb557 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -6662,6 +6662,12 @@ static int kvmppc_book3s_init_hv(void) return r; } + r = kvmppc_register_pmu(); + if (r) { + pr_err("KVM-HV: Unable to register PMUs %d\n", r); + goto err; + } + kvm_ops_hv.owner = THIS_MODULE; kvmppc_hv_ops = &kvm_ops_hv; @@ -6676,6 +6682,7 @@ static int kvmppc_book3s_init_hv(void) static void kvmppc_book3s_exit_hv(void) { + kvmppc_unregister_pmu(); kvmppc_uvmem_free(); kvmppc_free_host_rm_ops(); if (kvmppc_radix_possible()) diff --git a/arch/powerpc/kvm/book3s_hv_pmu.c b/arch/powerpc/kvm/book3s_hv_pmu.c new file mode 100644 index 000000000000..e72542d5e750 --- /dev/null +++ b/arch/powerpc/kvm/book3s_hv_pmu.c @@ -0,0 +1,133 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Description: PMUs specific to running nested KVM-HV guests + * on Book3S processors (specifically POWER9 and later). + */ + +#define pr_fmt(fmt) "kvmppc-pmu: " fmt + +#include "asm-generic/local64.h" +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/ratelimit.h> +#include <linux/kvm_host.h> +#include <linux/gfp_types.h> +#include <linux/pgtable.h> +#include <linux/perf_event.h> +#include <linux/spinlock_types.h> +#include <linux/spinlock.h> + +#include <asm/types.h> +#include <asm/kvm_ppc.h> +#include <asm/kvm_book3s.h> +#include <asm/mmu.h> +#include <asm/pgalloc.h> +#include <asm/pte-walk.h> +#include <asm/reg.h> +#include <asm/plpar_wrappers.h> +#include <asm/firmware.h> + +enum kvmppc_pmu_eventid { + KVMPPC_EVENT_MAX, +}; + +static struct attribute *kvmppc_pmu_events_attr[] = { + NULL, +}; + +static const struct attribute_group kvmppc_pmu_events_group = { + .name = "events", + .attrs = kvmppc_pmu_events_attr, +}; + +PMU_FORMAT_ATTR(event, "config:0"); +static struct attribute *kvmppc_pmu_format_attr[] = { + &format_attr_event.attr, + NULL, +}; + +static struct attribute_group kvmppc_pmu_format_group = { + .name = "format", + .attrs = kvmppc_pmu_format_attr, +}; + +static const struct attribute_group *kvmppc_pmu_attr_groups[] = { + &kvmppc_pmu_events_group, + &kvmppc_pmu_format_group, + NULL, +}; + +static int kvmppc_pmu_event_init(struct perf_event *event) +{ + unsigned int config = event->attr.config; + + pr_debug("%s: Event(%p) id=%llu cpu=%x on_cpu=%x config=%u", + __func__, event, event->id, event->cpu, + event->oncpu, config); + + if (event->attr.type != event->pmu->type) + return -ENOENT; + + if (config >= KVMPPC_EVENT_MAX) + return -EINVAL; + + local64_set(&event->hw.prev_count, 0); + local64_set(&event->count, 0); + + return 0; +} + +static void kvmppc_pmu_del(struct perf_event *event, int flags) +{ +} + +static int kvmppc_pmu_add(struct perf_event *event, int flags) +{ + return 0; +} + +static void kvmppc_pmu_read(struct perf_event *event) +{ +} + +/* L1 wide counters PMU */ +static struct pmu kvmppc_pmu = { + .task_ctx_nr = perf_sw_context, + .name = "kvm-hv", + .event_init = kvmppc_pmu_event_init, + .add = kvmppc_pmu_add, + .del = kvmppc_pmu_del, + .read = kvmppc_pmu_read, + .attr_groups = kvmppc_pmu_attr_groups, + .type = -1, +}; + +int kvmppc_register_pmu(void) +{ + int rc = -EOPNOTSUPP; + + /* only support events for nestedv2 right now */ + if (kvmhv_is_nestedv2()) { + /* Setup done now register the PMU */ + pr_info("Registering kvm-hv pmu"); + + /* Register only if we arent already registyered */ + rc = (kvmppc_pmu.type == -1) ? + perf_pmu_register(&kvmppc_pmu, kvmppc_pmu.name, + -1) : 0; + } + + return rc; +} +EXPORT_SYMBOL_GPL(kvmppc_register_pmu); + +void kvmppc_unregister_pmu(void) +{ + if (kvmhv_is_nestedv2()) { + if (kvmppc_pmu.type != -1) + perf_pmu_unregister(&kvmppc_pmu); + + pr_info("kvmhv_pmu unregistered.\n"); + } +} +EXPORT_SYMBOL_GPL(kvmppc_unregister_pmu);
Introduce a new PMU named 'kvm-hv' to report Book3s kvm-hv specific performance counters. This will expose KVM-HV specific performance attributes to user-space via kernel's PMU infrastructure and would enable users to monitor active kvm-hv based guests. The patch creates necessary scaffolding to for the new PMU callbacks and introduces two new exports kvmppc_{,un}register_pmu() that are called from kvm-hv init and exit function to perform initialize and cleanup for the 'kvm-hv' PMU. The patch doesn't introduce any perf-events yet, which will be introduced in later patches Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com> --- arch/powerpc/include/asm/kvm_book3s.h | 12 +++ arch/powerpc/kvm/Makefile | 6 ++ arch/powerpc/kvm/book3s_hv.c | 7 ++ arch/powerpc/kvm/book3s_hv_pmu.c | 133 ++++++++++++++++++++++++++ 4 files changed, 158 insertions(+) create mode 100644 arch/powerpc/kvm/book3s_hv_pmu.c