[RESEND PATCH v5 4/6] kvm powerpc/book3s-apiv2: Introduce kvm-hv specific PMU
Introduce a new PMU named 'kvm-hv' inside a new module named 'kvm-hv-pmu'
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 enableusers to monitor active kvm-hv based guests.
The patch creates necessary scaffolding to for the new PMU callbacks and
introduces the new kernel module name 'kvm-hv-pmu' which is built with
CONFIG_KVM_BOOK3S_HV_PMU. The patch doesn't introduce any perf-events yet,
which will be introduced in later patches
Signed-off-by: Vaibhav Jain
---
Changelog
v5->resend:
* Rebase the patch to latest upstream kernel tree
v4->v5:
* Fixed a kismet warning reported by build-robot by removing dependency to
CONFIG_HV_PERF_CTRS
https://lore.kernel.org/oe-kbuild-all/202502280218.jdd4jjlz-...@intel.com/
* Removed a redundant check in kvmppc_register_pmu() [ Athira ]
v3->v4:
* Introduced a new kernel module named 'kmv-hv-pmu' to host the new PMU
instead of building the as part of KVM-HV module. [ Maddy ]
* Moved the code from arch/powerpc/kvm to arch/powerpc/perf [ Athira ]
* Added a new config named KVM_BOOK3S_HV_PMU to arch/powerpc/kvm/Kconfig
v2->v3:
* Fixed a build warning reported by kernel build robot.
Link:
https://lore.kernel.org/oe-kbuild-all/202501171030.3x0gqw8g-...@intel.com
v1->v2:
* Fixed an issue of kvm-hv not loading on baremetal kvm [Gautam]
---
arch/powerpc/kvm/Kconfig | 13
arch/powerpc/perf/Makefile | 2 +
arch/powerpc/perf/kvm-hv-pmu.c | 138 +
3 files changed, 153 insertions(+)
create mode 100644 arch/powerpc/perf/kvm-hv-pmu.c
diff --git a/arch/powerpc/kvm/Kconfig b/arch/powerpc/kvm/Kconfig
index dbfdc126bf14..2f2702c867f7 100644
--- a/arch/powerpc/kvm/Kconfig
+++ b/arch/powerpc/kvm/Kconfig
@@ -83,6 +83,7 @@ config KVM_BOOK3S_64_HV
depends on KVM_BOOK3S_64 && PPC_POWERNV
select KVM_BOOK3S_HV_POSSIBLE
select KVM_GENERIC_MMU_NOTIFIER
+ select KVM_BOOK3S_HV_PMU
select CMA
help
Support running unmodified book3s_64 guest kernels in
@@ -171,6 +172,18 @@ config KVM_BOOK3S_HV_NESTED_PMU_WORKAROUND
those buggy L1s which saves the L2 state, at the cost of performance
in all nested-capable guest entry/exit.
+config KVM_BOOK3S_HV_PMU
+ tristate "Hypervisor Perf events for KVM Book3s-HV"
+ depends on KVM_BOOK3S_64_HV
+ help
+ Enable Book3s-HV Hypervisor Perf events PMU named 'kvm-hv'. These
+ Perf events give an overview of hypervisor performance overall
+ instead of a specific guests. Currently the PMU reports
+ L0-Hypervisor stats on a kvm-hv enabled PSeries LPAR like:
+ * Total/Used Guest-Heap
+ * Total/Used Guest Page-table Memory
+ * Total amount of Guest Page-table Memory reclaimed
+
config KVM_BOOKE_HV
bool
diff --git a/arch/powerpc/perf/Makefile b/arch/powerpc/perf/Makefile
index ac2cf58d62db..7f53fcb7495a 100644
--- a/arch/powerpc/perf/Makefile
+++ b/arch/powerpc/perf/Makefile
@@ -18,6 +18,8 @@ obj-$(CONFIG_HV_PERF_CTRS) += hv-24x7.o hv-gpci.o hv-common.o
obj-$(CONFIG_VPA_PMU) += vpa-pmu.o
+obj-$(CONFIG_KVM_BOOK3S_HV_PMU) += kvm-hv-pmu.o
+
obj-$(CONFIG_PPC_8xx) += 8xx-pmu.o
obj-$(CONFIG_PPC64)+= $(obj64-y)
diff --git a/arch/powerpc/perf/kvm-hv-pmu.c b/arch/powerpc/perf/kvm-hv-pmu.c
new file mode 100644
index ..12f40a7b3ced
--- /dev/null
+++ b/arch/powerpc/perf/kvm-hv-pmu.c
@@ -0,0 +1,138 @@
+// 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
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+
+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-
[PATCH v5 4/6] kvm powerpc/book3s-apiv2: Introduce kvm-hv specific PMU
Introduce a new PMU named 'kvm-hv' inside a new module named 'kvm-hv-pmu'
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 enableusers to monitor active kvm-hv based guests.
The patch creates necessary scaffolding to for the new PMU callbacks and
introduces the new kernel module name 'kvm-hv-pmu' which is built with
CONFIG_KVM_BOOK3S_HV_PMU. The patch doesn't introduce any perf-events yet,
which will be introduced in later patches
Signed-off-by: Vaibhav Jain
---
Changelog
v4->v5:
* Fixed a kismet warning reported by build-robot by removing dependency to
CONFIG_HV_PERF_CTRS
https://lore.kernel.org/oe-kbuild-all/202502280218.jdd4jjlz-...@intel.com/
* Removed a redundant check in kvmppc_register_pmu() [ Atheera ]
v3->v4:
* Introduced a new kernel module named 'kmv-hv-pmu' to host the new PMU
instead of building the as part of KVM-HV module. [ Maddy ]
* Moved the code from arch/powerpc/kvm to arch/powerpc/perf [ Atheera ]
* Added a new config named KVM_BOOK3S_HV_PMU to arch/powerpc/kvm/Kconfig
v2->v3:
* Fixed a build warning reported by kernel build robot.
Link:
https://lore.kernel.org/oe-kbuild-all/202501171030.3x0gqw8g-...@intel.com
v1->v2:
* Fixed an issue of kvm-hv not loading on baremetal kvm [Gautam]
---
arch/powerpc/kvm/Kconfig | 13
arch/powerpc/perf/Makefile | 2 +
arch/powerpc/perf/kvm-hv-pmu.c | 138 +
3 files changed, 153 insertions(+)
create mode 100644 arch/powerpc/perf/kvm-hv-pmu.c
diff --git a/arch/powerpc/kvm/Kconfig b/arch/powerpc/kvm/Kconfig
index dbfdc126bf14..2f2702c867f7 100644
--- a/arch/powerpc/kvm/Kconfig
+++ b/arch/powerpc/kvm/Kconfig
@@ -83,6 +83,7 @@ config KVM_BOOK3S_64_HV
depends on KVM_BOOK3S_64 && PPC_POWERNV
select KVM_BOOK3S_HV_POSSIBLE
select KVM_GENERIC_MMU_NOTIFIER
+ select KVM_BOOK3S_HV_PMU
select CMA
help
Support running unmodified book3s_64 guest kernels in
@@ -171,6 +172,18 @@ config KVM_BOOK3S_HV_NESTED_PMU_WORKAROUND
those buggy L1s which saves the L2 state, at the cost of performance
in all nested-capable guest entry/exit.
+config KVM_BOOK3S_HV_PMU
+ tristate "Hypervisor Perf events for KVM Book3s-HV"
+ depends on KVM_BOOK3S_64_HV
+ help
+ Enable Book3s-HV Hypervisor Perf events PMU named 'kvm-hv'. These
+ Perf events give an overview of hypervisor performance overall
+ instead of a specific guests. Currently the PMU reports
+ L0-Hypervisor stats on a kvm-hv enabled PSeries LPAR like:
+ * Total/Used Guest-Heap
+ * Total/Used Guest Page-table Memory
+ * Total amount of Guest Page-table Memory reclaimed
+
config KVM_BOOKE_HV
bool
diff --git a/arch/powerpc/perf/Makefile b/arch/powerpc/perf/Makefile
index ac2cf58d62db..7f53fcb7495a 100644
--- a/arch/powerpc/perf/Makefile
+++ b/arch/powerpc/perf/Makefile
@@ -18,6 +18,8 @@ obj-$(CONFIG_HV_PERF_CTRS) += hv-24x7.o hv-gpci.o hv-common.o
obj-$(CONFIG_VPA_PMU) += vpa-pmu.o
+obj-$(CONFIG_KVM_BOOK3S_HV_PMU) += kvm-hv-pmu.o
+
obj-$(CONFIG_PPC_8xx) += 8xx-pmu.o
obj-$(CONFIG_PPC64)+= $(obj64-y)
diff --git a/arch/powerpc/perf/kvm-hv-pmu.c b/arch/powerpc/perf/kvm-hv-pmu.c
new file mode 100644
index ..12f40a7b3ced
--- /dev/null
+++ b/arch/powerpc/perf/kvm-hv-pmu.c
@@ -0,0 +1,138 @@
+// 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
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+
+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 -ENOEN
