MIPS: KVM: Add kvm_aux trace event

Add a MIPS specific trace event for auxiliary context operations
(notably FPU and MSA). Unfortunately the generic kvm_fpu trace event
isn't flexible enough to handle the range of interesting things that can
happen with FPU and MSA context.

The type of state being operated on is traced:
- FPU: Just the FPU registers.
- MSA: Just the upper half of the MSA vector registers (low half already
       loaded with FPU state).
- FPU & MSA: Full MSA vector state (includes FPU state).

As is the type of operation:
- Restore: State was enabled and restored.
- Save: State was saved and disabled.
- Enable: State was enabled (already loaded).
- Disable: State was disabled (kept loaded).
- Discard: State was discarded and disabled.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
[Fix remaining occurrence of "fpu_msa", change to "aux". - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index 9093262ff3cec41af1f0c7dd0e8c5e4795b074a6..c0e8f8640f2bbff9a7ffe566c7d39a50b6751ce1 100644 (file)
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -1465,6 +1465,9 @@ void kvm_own_fpu(struct kvm_vcpu *vcpu)
        if (!(vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU)) {
                __kvm_restore_fpu(&vcpu->arch);
                vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
+               trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_FPU);
+       } else {
+               trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_FPU);
        }
 
        preempt_enable();
@@ -1513,6 +1516,7 @@ void kvm_own_msa(struct kvm_vcpu *vcpu)
                 */
                __kvm_restore_msa_upper(&vcpu->arch);
                vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
+               trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_MSA);
                break;
        case 0:
                /* Neither FPU or MSA already active, restore full MSA state */
@@ -1520,8 +1524,11 @@ void kvm_own_msa(struct kvm_vcpu *vcpu)
                vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
                if (kvm_mips_guest_has_fpu(&vcpu->arch))
                        vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
+               trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE,
+                             KVM_TRACE_AUX_FPU_MSA);
                break;
        default:
+               trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_MSA);
                break;
        }
 
@@ -1535,10 +1542,12 @@ void kvm_drop_fpu(struct kvm_vcpu *vcpu)
        preempt_disable();
        if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
                disable_msa();
+               trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_MSA);
                vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_MSA;
        }
        if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
                clear_c0_status(ST0_CU1 | ST0_FR);
+               trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_FPU);
                vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
        }
        preempt_enable();
@@ -1560,6 +1569,7 @@ void kvm_lose_fpu(struct kvm_vcpu *vcpu)
                enable_fpu_hazard();
 
                __kvm_save_msa(&vcpu->arch);
+               trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU_MSA);
 
                /* Disable MSA & FPU */
                disable_msa();
@@ -1574,6 +1584,7 @@ void kvm_lose_fpu(struct kvm_vcpu *vcpu)
 
                __kvm_save_fpu(&vcpu->arch);
                vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
+               trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU);
 
                /* Disable FPU */
                clear_c0_status(ST0_CU1 | ST0_FR);

diff --git a/arch/mips/kvm/trace.h b/arch/mips/kvm/trace.h
index bd6437f67dc03b01c3a76e57a53a811a61f0ebe7..f3ada591ca2538006dfc907bbc6109f0da4cce89 100644 (file)
--- a/arch/mips/kvm/trace.h
+++ b/arch/mips/kvm/trace.h
@@ -38,6 +38,52 @@ TRACE_EVENT(kvm_exit,
                      __entry->pc)
 );
 
+#define KVM_TRACE_AUX_RESTORE          0
+#define KVM_TRACE_AUX_SAVE             1
+#define KVM_TRACE_AUX_ENABLE           2
+#define KVM_TRACE_AUX_DISABLE          3
+#define KVM_TRACE_AUX_DISCARD          4
+
+#define KVM_TRACE_AUX_FPU              1
+#define KVM_TRACE_AUX_MSA              2
+#define KVM_TRACE_AUX_FPU_MSA          3
+
+#define kvm_trace_symbol_aux_op                \
+       { KVM_TRACE_AUX_RESTORE, "restore" },   \
+       { KVM_TRACE_AUX_SAVE,    "save" },      \
+       { KVM_TRACE_AUX_ENABLE,  "enable" },    \
+       { KVM_TRACE_AUX_DISABLE, "disable" },   \
+       { KVM_TRACE_AUX_DISCARD, "discard" }
+
+#define kvm_trace_symbol_aux_state             \
+       { KVM_TRACE_AUX_FPU,     "FPU" },       \
+       { KVM_TRACE_AUX_MSA,     "MSA" },       \
+       { KVM_TRACE_AUX_FPU_MSA, "FPU & MSA" }
+
+TRACE_EVENT(kvm_aux,
+           TP_PROTO(struct kvm_vcpu *vcpu, unsigned int op,
+                    unsigned int state),
+           TP_ARGS(vcpu, op, state),
+           TP_STRUCT__entry(
+                       __field(unsigned long, pc)
+                       __field(u8, op)
+                       __field(u8, state)
+           ),
+
+           TP_fast_assign(
+                       __entry->pc = vcpu->arch.pc;
+                       __entry->op = op;
+                       __entry->state = state;
+           ),
+
+           TP_printk("%s %s PC: 0x%08lx",
+                     __print_symbolic(__entry->op,
+                                      kvm_trace_symbol_aux_op),
+                     __print_symbolic(__entry->state,
+                                      kvm_trace_symbol_aux_state),
+                     __entry->pc)
+);
+
 #endif /* _TRACE_KVM_H */
 
 /* This part must be outside protection */