From f26f9933e3e31b2117b804b6b8932388db88a131 Mon Sep 17 00:00:00 2001 From: Kajol Jain Date: Mon, 18 Nov 2024 17:11:14 +0530 Subject: [PATCH] powerpc/perf: Add per-task/process monitoring to vpa_pmu driver 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 Co-developed-by: Madhavan Srinivasan Signed-off-by: Madhavan Srinivasan Signed-off-by: Michael Ellerman Link: https://patch.msgid.link/20241118114114.208964-4-kjain@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 f620e3126d688..b936e174eefd1 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 613231c436e7b..d8938fdf19362 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -4190,6 +4190,51 @@ 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 c143c626b4a02..6a5bfd2a13b5a 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;