KVM: Add trace markers

Trace markers allow userspace to trace execution of a virtual machine
in order to monitor its performance.

Signed-off-by: Feng (Eric) Liu <eric.e.liu@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 6249810..8e5d664 100644 (file)
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -1843,6 +1843,8 @@ static void vmx_inject_irq(struct kvm_vcpu *vcpu, int irq)
 {
        struct vcpu_vmx *vmx = to_vmx(vcpu);
 
+       KVMTRACE_1D(INJ_VIRQ, vcpu, (u32)irq, handler);
+
        if (vcpu->arch.rmode.active) {
                vmx->rmode.irq.pending = true;
                vmx->rmode.irq.vector = irq;
@@ -1993,6 +1995,8 @@ static int handle_exception(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
                error_code = vmcs_read32(VM_EXIT_INTR_ERROR_CODE);
        if (is_page_fault(intr_info)) {
                cr2 = vmcs_readl(EXIT_QUALIFICATION);
+               KVMTRACE_3D(PAGE_FAULT, vcpu, error_code, (u32)cr2,
+                           (u32)((u64)cr2 >> 32), handler);
                return kvm_mmu_page_fault(vcpu, cr2, error_code);
        }
 
@@ -2021,6 +2025,7 @@ static int handle_external_interrupt(struct kvm_vcpu *vcpu,
                                     struct kvm_run *kvm_run)
 {
        ++vcpu->stat.irq_exits;
+       KVMTRACE_1D(INTR, vcpu, vmcs_read32(VM_EXIT_INTR_INFO), handler);
        return 1;
 }
 
@@ -2078,6 +2083,8 @@ static int handle_cr(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
        reg = (exit_qualification >> 8) & 15;
        switch ((exit_qualification >> 4) & 3) {
        case 0: /* mov to cr */
+               KVMTRACE_3D(CR_WRITE, vcpu, (u32)cr, (u32)vcpu->arch.regs[reg],
+                           (u32)((u64)vcpu->arch.regs[reg] >> 32), handler);
                switch (cr) {
                case 0:
                        vcpu_load_rsp_rip(vcpu);
@@ -2110,6 +2117,7 @@ static int handle_cr(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
                vcpu->arch.cr0 &= ~X86_CR0_TS;
                vmcs_writel(CR0_READ_SHADOW, vcpu->arch.cr0);
                vmx_fpu_activate(vcpu);
+               KVMTRACE_0D(CLTS, vcpu, handler);
                skip_emulated_instruction(vcpu);
                return 1;
        case 1: /*mov from cr*/
@@ -2118,12 +2126,18 @@ static int handle_cr(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
                        vcpu_load_rsp_rip(vcpu);
                        vcpu->arch.regs[reg] = vcpu->arch.cr3;
                        vcpu_put_rsp_rip(vcpu);
+                       KVMTRACE_3D(CR_READ, vcpu, (u32)cr,
+                                   (u32)vcpu->arch.regs[reg],
+                                   (u32)((u64)vcpu->arch.regs[reg] >> 32),
+                                   handler);
                        skip_emulated_instruction(vcpu);
                        return 1;
                case 8:
                        vcpu_load_rsp_rip(vcpu);
                        vcpu->arch.regs[reg] = kvm_get_cr8(vcpu);
                        vcpu_put_rsp_rip(vcpu);
+                       KVMTRACE_2D(CR_READ, vcpu, (u32)cr,
+                                   (u32)vcpu->arch.regs[reg], handler);
                        skip_emulated_instruction(vcpu);
                        return 1;
                }
@@ -2169,6 +2183,7 @@ static int handle_dr(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
                        val = 0;
                }
                vcpu->arch.regs[reg] = val;
+               KVMTRACE_2D(DR_READ, vcpu, (u32)dr, (u32)val, handler);
        } else {
                /* mov to dr */
        }
@@ -2193,6 +2208,9 @@ static int handle_rdmsr(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
                return 1;
        }
 
+       KVMTRACE_3D(MSR_READ, vcpu, ecx, (u32)data, (u32)(data >> 32),
+                   handler);
+
        /* FIXME: handling of bits 32:63 of rax, rdx */
        vcpu->arch.regs[VCPU_REGS_RAX] = data & -1u;
        vcpu->arch.regs[VCPU_REGS_RDX] = (data >> 32) & -1u;
@@ -2206,6 +2224,9 @@ static int handle_wrmsr(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
        u64 data = (vcpu->arch.regs[VCPU_REGS_RAX] & -1u)
                | ((u64)(vcpu->arch.regs[VCPU_REGS_RDX] & -1u) << 32);
 
+       KVMTRACE_3D(MSR_WRITE, vcpu, ecx, (u32)data, (u32)(data >> 32),
+                   handler);
+
        if (vmx_set_msr(vcpu, ecx, data) != 0) {
                kvm_inject_gp(vcpu, 0);
                return 1;
@@ -2230,6 +2251,9 @@ static int handle_interrupt_window(struct kvm_vcpu *vcpu,
        cpu_based_vm_exec_control = vmcs_read32(CPU_BASED_VM_EXEC_CONTROL);
        cpu_based_vm_exec_control &= ~CPU_BASED_VIRTUAL_INTR_PENDING;
        vmcs_write32(CPU_BASED_VM_EXEC_CONTROL, cpu_based_vm_exec_control);
+
+       KVMTRACE_0D(PEND_INTR, vcpu, handler);
+
        /*
         * If the user space waits to inject interrupts, exit as soon as
         * possible
@@ -2272,6 +2296,8 @@ static int handle_apic_access(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
        exit_qualification = vmcs_read64(EXIT_QUALIFICATION);
        offset = exit_qualification & 0xffful;
 
+       KVMTRACE_1D(APIC_ACCESS, vcpu, (u32)offset, handler);
+
        er = emulate_instruction(vcpu, kvm_run, 0, 0, 0);
 
        if (er !=  EMULATE_DONE) {
@@ -2335,6 +2361,9 @@ static int kvm_handle_exit(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu)
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        u32 vectoring_info = vmx->idt_vectoring_info;
 
+       KVMTRACE_3D(VMEXIT, vcpu, exit_reason, (u32)vmcs_readl(GUEST_RIP),
+                   (u32)((u64)vmcs_readl(GUEST_RIP) >> 32), entryexit);
+
        if (unlikely(vmx->fail)) {
                kvm_run->exit_reason = KVM_EXIT_FAIL_ENTRY;
                kvm_run->fail_entry.hardware_entry_failure_reason
@@ -2416,6 +2445,8 @@ static void vmx_intr_assist(struct kvm_vcpu *vcpu)
                        return;
                }
 
+               KVMTRACE_1D(REDELIVER_EVT, vcpu, idtv_info_field, handler);
+
                vmcs_write32(VM_ENTRY_INTR_INFO_FIELD, idtv_info_field);
                vmcs_write32(VM_ENTRY_INSTRUCTION_LEN,
                                vmcs_read32(VM_EXIT_INSTRUCTION_LEN));
@@ -2601,8 +2632,10 @@ static void vmx_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
        intr_info = vmcs_read32(VM_EXIT_INTR_INFO);
 
        /* We need to handle NMIs before interrupts are enabled */
-       if ((intr_info & INTR_INFO_INTR_TYPE_MASK) == 0x200) /* nmi */
+       if ((intr_info & INTR_INFO_INTR_TYPE_MASK) == 0x200) { /* nmi */
+               KVMTRACE_0D(NMI, vcpu, handler);
                asm("int $2");
+       }
 }
 
 static void vmx_free_vmcs(struct kvm_vcpu *vcpu)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index c7ad235..f070f0a 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -303,6 +303,9 @@ EXPORT_SYMBOL_GPL(kvm_set_cr0);
 void kvm_lmsw(struct kvm_vcpu *vcpu, unsigned long msw)
 {
        kvm_set_cr0(vcpu, (vcpu->arch.cr0 & ~0x0ful) | (msw & 0x0f));
+       KVMTRACE_1D(LMSW, vcpu,
+                   (u32)((vcpu->arch.cr0 & ~0x0ful) | (msw & 0x0f)),
+                   handler);
 }
 EXPORT_SYMBOL_GPL(kvm_lmsw);
 
@@ -2269,6 +2272,13 @@ int kvm_emulate_pio(struct kvm_vcpu *vcpu, struct kvm_run *run, int in,
        vcpu->arch.pio.guest_page_offset = 0;
        vcpu->arch.pio.rep = 0;
 
+       if (vcpu->run->io.direction == KVM_EXIT_IO_IN)
+               KVMTRACE_2D(IO_READ, vcpu, vcpu->run->io.port, (u32)size,
+                           handler);
+       else
+               KVMTRACE_2D(IO_WRITE, vcpu, vcpu->run->io.port, (u32)size,
+                           handler);
+
        kvm_x86_ops->cache_regs(vcpu);
        memcpy(vcpu->arch.pio_data, &vcpu->arch.regs[VCPU_REGS_RAX], 4);
        kvm_x86_ops->decache_regs(vcpu);
@@ -2307,6 +2317,13 @@ int kvm_emulate_pio_string(struct kvm_vcpu *vcpu, struct kvm_run *run, int in,
        vcpu->arch.pio.guest_page_offset = offset_in_page(address);
        vcpu->arch.pio.rep = rep;
 
+       if (vcpu->run->io.direction == KVM_EXIT_IO_IN)
+               KVMTRACE_2D(IO_READ, vcpu, vcpu->run->io.port, (u32)size,
+                           handler);
+       else
+               KVMTRACE_2D(IO_WRITE, vcpu, vcpu->run->io.port, (u32)size,
+                           handler);
+
        if (!count) {
                kvm_x86_ops->skip_emulated_instruction(vcpu);
                return 1;
@@ -2414,6 +2431,7 @@ void kvm_arch_exit(void)
 int kvm_emulate_halt(struct kvm_vcpu *vcpu)
 {
        ++vcpu->stat.halt_exits;
+       KVMTRACE_0D(HLT, vcpu, handler);
        if (irqchip_in_kernel(vcpu->kvm)) {
                vcpu->arch.mp_state = VCPU_MP_STATE_HALTED;
                up_read(&vcpu->kvm->slots_lock);
@@ -2451,6 +2469,8 @@ int kvm_emulate_hypercall(struct kvm_vcpu *vcpu)
        a2 = vcpu->arch.regs[VCPU_REGS_RDX];
        a3 = vcpu->arch.regs[VCPU_REGS_RSI];
 
+       KVMTRACE_1D(VMMCALL, vcpu, (u32)nr, handler);
+
        if (!is_long_mode(vcpu)) {
                nr &= 0xFFFFFFFF;
                a0 &= 0xFFFFFFFF;
@@ -2639,6 +2659,11 @@ void kvm_emulate_cpuid(struct kvm_vcpu *vcpu)
        }
        kvm_x86_ops->decache_regs(vcpu);
        kvm_x86_ops->skip_emulated_instruction(vcpu);
+       KVMTRACE_5D(CPUID, vcpu, function,
+                   (u32)vcpu->arch.regs[VCPU_REGS_RAX],
+                   (u32)vcpu->arch.regs[VCPU_REGS_RBX],
+                   (u32)vcpu->arch.regs[VCPU_REGS_RCX],
+                   (u32)vcpu->arch.regs[VCPU_REGS_RDX], handler);
 }
 EXPORT_SYMBOL_GPL(kvm_emulate_cpuid);
 
@@ -2794,6 +2819,7 @@ again:
                if (test_and_clear_bit(KVM_REQ_TLB_FLUSH, &vcpu->requests))
                        kvm_x86_ops->tlb_flush(vcpu);
 
+       KVMTRACE_0D(VMENTRY, vcpu, entryexit);
        kvm_x86_ops->run(vcpu, kvm_run);
 
        vcpu->guest_mode = 0;

diff --git a/include/asm-x86/kvm.h b/include/asm-x86/kvm.h
index 12b4b25..80eefef 100644 (file)
--- a/include/asm-x86/kvm.h
+++ b/include/asm-x86/kvm.h
@@ -209,4 +209,24 @@ struct kvm_pit_state {
        struct kvm_pit_channel_state channels[3];
 };
 
+#define KVM_TRC_INJ_VIRQ         (KVM_TRC_HANDLER + 0x02)
+#define KVM_TRC_REDELIVER_EVT    (KVM_TRC_HANDLER + 0x03)
+#define KVM_TRC_PEND_INTR        (KVM_TRC_HANDLER + 0x04)
+#define KVM_TRC_IO_READ          (KVM_TRC_HANDLER + 0x05)
+#define KVM_TRC_IO_WRITE         (KVM_TRC_HANDLER + 0x06)
+#define KVM_TRC_CR_READ          (KVM_TRC_HANDLER + 0x07)
+#define KVM_TRC_CR_WRITE         (KVM_TRC_HANDLER + 0x08)
+#define KVM_TRC_DR_READ          (KVM_TRC_HANDLER + 0x09)
+#define KVM_TRC_DR_WRITE         (KVM_TRC_HANDLER + 0x0A)
+#define KVM_TRC_MSR_READ         (KVM_TRC_HANDLER + 0x0B)
+#define KVM_TRC_MSR_WRITE        (KVM_TRC_HANDLER + 0x0C)
+#define KVM_TRC_CPUID            (KVM_TRC_HANDLER + 0x0D)
+#define KVM_TRC_INTR             (KVM_TRC_HANDLER + 0x0E)
+#define KVM_TRC_NMI              (KVM_TRC_HANDLER + 0x0F)
+#define KVM_TRC_VMMCALL          (KVM_TRC_HANDLER + 0x10)
+#define KVM_TRC_HLT              (KVM_TRC_HANDLER + 0x11)
+#define KVM_TRC_CLTS             (KVM_TRC_HANDLER + 0x12)
+#define KVM_TRC_LMSW             (KVM_TRC_HANDLER + 0x13)
+#define KVM_TRC_APIC_ACCESS      (KVM_TRC_HANDLER + 0x14)
+
 #endif

diff --git a/include/asm-x86/kvm_host.h b/include/asm-x86/kvm_host.h
index 2861178..15169cb 100644 (file)
--- a/include/asm-x86/kvm_host.h
+++ b/include/asm-x86/kvm_host.h
@@ -667,4 +667,23 @@ enum {
        TASK_SWITCH_GATE = 3,
 };
 
+#define KVMTRACE_5D(evt, vcpu, d1, d2, d3, d4, d5, name) \
+       trace_mark(kvm_trace_##name, "%u %p %u %u %u %u %u %u", KVM_TRC_##evt, \
+                                               vcpu, 5, d1, d2, d3, d4, d5)
+#define KVMTRACE_4D(evt, vcpu, d1, d2, d3, d4, name) \
+       trace_mark(kvm_trace_##name, "%u %p %u %u %u %u %u %u", KVM_TRC_##evt, \
+                                               vcpu, 4, d1, d2, d3, d4, 0)
+#define KVMTRACE_3D(evt, vcpu, d1, d2, d3, name) \
+       trace_mark(kvm_trace_##name, "%u %p %u %u %u %u %u %u", KVM_TRC_##evt, \
+                                               vcpu, 3, d1, d2, d3, 0, 0)
+#define KVMTRACE_2D(evt, vcpu, d1, d2, name) \
+       trace_mark(kvm_trace_##name, "%u %p %u %u %u %u %u %u", KVM_TRC_##evt, \
+                                               vcpu, 2, d1, d2, 0, 0, 0)
+#define KVMTRACE_1D(evt, vcpu, d1, name) \
+       trace_mark(kvm_trace_##name, "%u %p %u %u %u %u %u %u", KVM_TRC_##evt, \
+                                               vcpu, 1, d1, 0, 0, 0, 0)
+#define KVMTRACE_0D(evt, vcpu, name) \
+       trace_mark(kvm_trace_##name, "%u %p %u %u %u %u %u %u", KVM_TRC_##evt, \
+                                               vcpu, 0, 0, 0, 0, 0, 0)
+
 #endif

diff --git a/include/linux/kvm.h b/include/linux/kvm.h
index f04bb42..d302d63 100644 (file)
--- a/include/linux/kvm.h
+++ b/include/linux/kvm.h
@@ -14,6 +14,12 @@
 
 #define KVM_API_VERSION 12
 
+/* for KVM_TRACE_ENABLE */
+struct kvm_user_trace_setup {
+       __u32 buf_size; /* sub_buffer size of each per-cpu */
+       __u32 buf_nr; /* the number of sub_buffers of each per-cpu */
+};
+
 /* for KVM_CREATE_MEMORY_REGION */
 struct kvm_memory_region {
        __u32 slot;
@@ -242,6 +248,42 @@ struct kvm_s390_interrupt {
        __u64 parm64;
 };
 
+#define KVM_TRC_SHIFT           16
+/*
+ * kvm trace categories
+ */
+#define KVM_TRC_ENTRYEXIT       (1 << KVM_TRC_SHIFT)
+#define KVM_TRC_HANDLER         (1 << (KVM_TRC_SHIFT + 1)) /* only 12 bits */
+
+/*
+ * kvm trace action
+ */
+#define KVM_TRC_VMENTRY         (KVM_TRC_ENTRYEXIT + 0x01)
+#define KVM_TRC_VMEXIT          (KVM_TRC_ENTRYEXIT + 0x02)
+#define KVM_TRC_PAGE_FAULT      (KVM_TRC_HANDLER + 0x01)
+
+#define KVM_TRC_HEAD_SIZE       12
+#define KVM_TRC_CYCLE_SIZE      8
+#define KVM_TRC_EXTRA_MAX       7
+
+/* This structure represents a single trace buffer record. */
+struct kvm_trace_rec {
+       __u32 event:28;
+       __u32 extra_u32:3;
+       __u32 cycle_in:1;
+       __u32 pid;
+       __u32 vcpu_id;
+       union {
+               struct {
+                       __u32 cycle_lo, cycle_hi;
+                       __u32 extra_u32[KVM_TRC_EXTRA_MAX];
+               } cycle;
+               struct {
+                       __u32 extra_u32[KVM_TRC_EXTRA_MAX];
+               } nocycle;
+       } u;
+};
+
 #define KVMIO 0xAE
 
 /*
@@ -262,7 +304,12 @@ struct kvm_s390_interrupt {
  */
 #define KVM_GET_VCPU_MMAP_SIZE    _IO(KVMIO,   0x04) /* in bytes */
 #define KVM_GET_SUPPORTED_CPUID   _IOWR(KVMIO, 0x05, struct kvm_cpuid2)
-
+/*
+ * ioctls for kvm trace
+ */
+#define KVM_TRACE_ENABLE          _IOW(KVMIO, 0x06, struct kvm_user_trace_setup)
+#define KVM_TRACE_PAUSE           _IO(KVMIO,  0x07)
+#define KVM_TRACE_DISABLE         _IO(KVMIO,  0x08)
 /*
  * Extension capability list.
  */