Enhance the vpa_pmu driver with a feature to observe context switch
latency event for both per-task (tid) and per-pid (pid) option.
Couple of new helper functions are added to hide the abstraction of
reading the context switch latency counter from kvm_vcpu_arch struct
and these helper functions are defined in the "kvm/book3s_hv.c".
"PERF_ATTACH_TASK" flag is used to decide whether to read the counter
values from lppaca or kvm_vcpu_arch struct.
Signed-off-by: Kajol Jain <kj...@linux.ibm.com>
Co-developed-by: Madhavan Srinivasan <ma...@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <ma...@linux.ibm.com>
---
arch/powerpc/include/asm/kvm_book3s_64.h | 3 ++
arch/powerpc/kvm/book3s_hv.c | 45 ++++++++++++++++++++++++
arch/powerpc/perf/vpa-pmu.c | 15 ++++++--
3 files changed, 60 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/include/asm/kvm_book3s_64.h
b/arch/powerpc/include/asm/kvm_book3s_64.h
index f620e3126d68..b936e174eefd 100644
--- a/arch/powerpc/include/asm/kvm_book3s_64.h
+++ b/arch/powerpc/include/asm/kvm_book3s_64.h
@@ -691,6 +691,9 @@ void kvmhv_set_l2_counters_status(int cpu, bool status);
u64 kvmhv_get_l1_to_l2_cs_time(void);
u64 kvmhv_get_l2_to_l1_cs_time(void);
u64 kvmhv_get_l2_runtime_agg(void);
+u64 kvmhv_get_l1_to_l2_cs_time_vcpu(void);
+u64 kvmhv_get_l2_to_l1_cs_time_vcpu(void);
+u64 kvmhv_get_l2_runtime_agg_vcpu(void);
#endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 4284437fedeb..ddc380982233 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -4214,6 +4214,51 @@ u64 kvmhv_get_l2_runtime_agg(void)
}
EXPORT_SYMBOL(kvmhv_get_l2_runtime_agg);
+u64 kvmhv_get_l1_to_l2_cs_time_vcpu(void)
+{
+ struct kvm_vcpu *vcpu;
+ struct kvm_vcpu_arch *arch;
+
+ vcpu = local_paca->kvm_hstate.kvm_vcpu;
+ if (vcpu) {
+ arch = &vcpu->arch;
+ return arch->l1_to_l2_cs;
+ } else {
+ return 0;
+ }
+}
+EXPORT_SYMBOL(kvmhv_get_l1_to_l2_cs_time_vcpu);
+
+u64 kvmhv_get_l2_to_l1_cs_time_vcpu(void)
+{
+ struct kvm_vcpu *vcpu;
+ struct kvm_vcpu_arch *arch;
+
+ vcpu = local_paca->kvm_hstate.kvm_vcpu;
+ if (vcpu) {
+ arch = &vcpu->arch;
+ return arch->l2_to_l1_cs;
+ } else {
+ return 0;
+ }
+}
+EXPORT_SYMBOL(kvmhv_get_l2_to_l1_cs_time_vcpu);
+
+u64 kvmhv_get_l2_runtime_agg_vcpu(void)
+{
+ struct kvm_vcpu *vcpu;
+ struct kvm_vcpu_arch *arch;
+
+ vcpu = local_paca->kvm_hstate.kvm_vcpu;
+ if (vcpu) {
+ arch = &vcpu->arch;
+ return arch->l2_runtime_agg;
+ } else {
+ return 0;
+ }
+}
+EXPORT_SYMBOL(kvmhv_get_l2_runtime_agg_vcpu);
+
#else
int kvmhv_get_l2_counters_status(void)
{
diff --git a/arch/powerpc/perf/vpa-pmu.c b/arch/powerpc/perf/vpa-pmu.c
index 2c785eee2f71..601de245392c 100644
--- a/arch/powerpc/perf/vpa-pmu.c
+++ b/arch/powerpc/perf/vpa-pmu.c
@@ -97,13 +97,22 @@ static unsigned long get_counter_data(struct perf_event
*event)
switch (config) {
case L1_TO_L2_CS_LAT:
- data = kvmhv_get_l1_to_l2_cs_time();
+ if (event->attach_state & PERF_ATTACH_TASK)
+ data = kvmhv_get_l1_to_l2_cs_time_vcpu();
+ else
+ data = kvmhv_get_l1_to_l2_cs_time();
break;
case L2_TO_L1_CS_LAT:
- data = kvmhv_get_l2_to_l1_cs_time();
+ if (event->attach_state & PERF_ATTACH_TASK)
+ data = kvmhv_get_l2_to_l1_cs_time_vcpu();
+ else
+ data = kvmhv_get_l2_to_l1_cs_time();
break;
case L2_RUNTIME_AGG:
- data = kvmhv_get_l2_runtime_agg();
+ if (event->attach_state & PERF_ATTACH_TASK)
+ data = kvmhv_get_l2_runtime_agg_vcpu();
+ else
+ data = kvmhv_get_l2_runtime_agg();
break;
default:
data = 0;
--
2.43.5
