summaryrefslogtreecommitdiffstats
path: root/arch/x86/kvm
diff options
context:
space:
mode:
authorSean Christopherson <seanjc@google.com>2022-03-11 04:35:17 +0000
committerPaolo Bonzini <pbonzini@redhat.com>2022-04-02 05:34:45 -0400
commit4f4c4a3ee53cc20569158a05f99b6c2d1f9c998a (patch)
tree4eb550737f2aed2802f689c472a3fecd79539e9a /arch/x86/kvm
parent320af55a930f30ba49d7cd663280d46705e11383 (diff)
downloadlinux-4f4c4a3ee53cc20569158a05f99b6c2d1f9c998a.tar.bz2
KVM: x86: Trace all APICv inhibit changes and capture overall status
Trace all APICv inhibit changes instead of just those that result in APICv being (un)inhibited, and log the current state. Debugging why APICv isn't working is frustrating as it's hard to see why APICv is still inhibited, and logging only the first inhibition means unnecessary onion peeling. Opportunistically drop the export of the tracepoint, it is not and should not be used by vendor code due to the need to serialize toggling via apicv_update_lock. Note, using the common flow means kvm_apicv_init() switched from atomic to non-atomic bitwise operations. The VM is unreachable at init, so non-atomic is perfectly ok. Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20220311043517.17027-4-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm')
-rw-r--r--arch/x86/kvm/trace.h18
-rw-r--r--arch/x86/kvm/x86.c29
2 files changed, 29 insertions, 18 deletions
diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h
index 105037a251b5..e3a24b8f04be 100644
--- a/arch/x86/kvm/trace.h
+++ b/arch/x86/kvm/trace.h
@@ -1339,23 +1339,25 @@ TRACE_EVENT(kvm_hv_stimer_cleanup,
__entry->vcpu_id, __entry->timer_index)
);
-TRACE_EVENT(kvm_apicv_update_request,
- TP_PROTO(int reason, bool activate),
- TP_ARGS(reason, activate),
+TRACE_EVENT(kvm_apicv_inhibit_changed,
+ TP_PROTO(int reason, bool set, unsigned long inhibits),
+ TP_ARGS(reason, set, inhibits),
TP_STRUCT__entry(
__field(int, reason)
- __field(bool, activate)
+ __field(bool, set)
+ __field(unsigned long, inhibits)
),
TP_fast_assign(
__entry->reason = reason;
- __entry->activate = activate;
+ __entry->set = set;
+ __entry->inhibits = inhibits;
),
- TP_printk("%s reason=%u",
- __entry->activate ? "activate" : "deactivate",
- __entry->reason)
+ TP_printk("%s reason=%u, inhibits=0x%lx",
+ __entry->set ? "set" : "cleared",
+ __entry->reason, __entry->inhibits)
);
TRACE_EVENT(kvm_apicv_accept_irq,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index ede81264c06f..129003ad3784 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9062,15 +9062,29 @@ bool kvm_apicv_activated(struct kvm *kvm)
}
EXPORT_SYMBOL_GPL(kvm_apicv_activated);
+
+static void set_or_clear_apicv_inhibit(unsigned long *inhibits,
+ enum kvm_apicv_inhibit reason, bool set)
+{
+ if (set)
+ __set_bit(reason, inhibits);
+ else
+ __clear_bit(reason, inhibits);
+
+ trace_kvm_apicv_inhibit_changed(reason, set, *inhibits);
+}
+
static void kvm_apicv_init(struct kvm *kvm)
{
+ unsigned long *inhibits = &kvm->arch.apicv_inhibit_reasons;
+
init_rwsem(&kvm->arch.apicv_update_lock);
- set_bit(APICV_INHIBIT_REASON_ABSENT,
- &kvm->arch.apicv_inhibit_reasons);
+ set_or_clear_apicv_inhibit(inhibits, APICV_INHIBIT_REASON_ABSENT, true);
+
if (!enable_apicv)
- set_bit(APICV_INHIBIT_REASON_DISABLE,
- &kvm->arch.apicv_inhibit_reasons);
+ set_or_clear_apicv_inhibit(inhibits,
+ APICV_INHIBIT_REASON_ABSENT, true);
}
static void kvm_sched_yield(struct kvm_vcpu *vcpu, unsigned long dest_id)
@@ -9756,13 +9770,9 @@ void __kvm_set_or_clear_apicv_inhibit(struct kvm *kvm,
old = new = kvm->arch.apicv_inhibit_reasons;
- if (set)
- __set_bit(reason, &new);
- else
- __clear_bit(reason, &new);
+ set_or_clear_apicv_inhibit(&new, reason, set);
if (!!old != !!new) {
- trace_kvm_apicv_update_request(reason, !set);
/*
* Kick all vCPUs before setting apicv_inhibit_reasons to avoid
* false positives in the sanity check WARN in svm_vcpu_run().
@@ -12945,7 +12955,6 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_pi_irte_update);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_unaccelerated_access);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_incomplete_ipi);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_ga_log);
-EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_apicv_update_request);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_apicv_accept_irq);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_vmgexit_enter);
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_vmgexit_exit);