agent: Support Kata agent tracing

Add configuration options to support the various Kata agent tracing modes and types. See the comments in the configuration files for details: - `cli/config/configuration-fc.toml` - `cli/config/configuration-qemu.toml` Fixes kata-containers#1369. Signed-off-by: James O. D. Hunt <[email protected]>
jodh-intel · Mar 28, 2019 · 8573c8d · 8573c8d
1 parent 952afd8
commit 8573c8d
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Showing 13 changed files with 410 additions and 40 deletions.
diff --git a/cli/config/configuration-fc.toml.in b/cli/config/configuration-fc.toml.in
@@ -226,6 +226,27 @@ path = "@SHIMPATH@"
 # (default: disabled)
 #enable_debug = true
 
+# Enable agent tracing.
+#
+# If enabled, the default trace mode is "dynamic" and the
+# default trace type is "isolated". The trace mode and type are set
+# explicity with the `trace_type=` and `trace_mode=` options.
+#
+# Notes:
+#
+# - Tracing is ONLY enabled when `enable_tracing` is set: explicitly
+#   setting `trace_mode=` and/or `trace_type=` without setting `enable_tracing`
+#   will NOT activate agent tracing.
+#
+# - See https://github.com/kata-containers/agent/blob/master/TRACING.md for
+#   full details.
+#
+# (default: disabled)
+#enable_tracing = true
+#
+#trace_mode = "dynamic"
+#trace_type = "isolated"
+
 [netmon]
 # If enabled, the network monitoring process gets started when the
 # sandbox is created. This allows for the detection of some additional

diff --git a/cli/config/configuration-qemu.toml.in b/cli/config/configuration-qemu.toml.in
@@ -273,6 +273,27 @@ path = "@SHIMPATH@"
 # (default: disabled)
 #enable_debug = true
 
+# Enable agent tracing.
+#
+# If enabled, the default trace mode is "dynamic" and the
+# default trace type is "isolated". The trace mode and type are set
+# explicity with the `trace_type=` and `trace_mode=` options.
+#
+# Notes:
+#
+# - Tracing is ONLY enabled when `enable_tracing` is set: explicitly
+#   setting `trace_mode=` and/or `trace_type=` without setting `enable_tracing`
+#   will NOT activate agent tracing.
+#
+# - See https://github.com/kata-containers/agent/blob/master/TRACING.md for
+#   full details.
+#
+# (default: disabled)
+#enable_tracing = true
+#
+#trace_mode = "dynamic"
+#trace_type = "isolated"
+
 [netmon]
 # If enabled, the network monitoring process gets started when the
 # sandbox is created. This allows for the detection of some additional

diff --git a/cli/kata-env.go b/cli/kata-env.go
@@ -27,7 +27,7 @@ import (
 //
 // XXX: Increment for every change to the output format
 // (meaning any change to the EnvInfo type).
-const formatVersion = "1.0.22"
+const formatVersion = "1.0.23"
 
 // MetaInfo stores information on the format of the output itself
 type MetaInfo struct {
@@ -112,8 +112,11 @@ type ShimInfo struct {
 
 // AgentInfo stores agent details
 type AgentInfo struct {
-	Type  string
-	Debug bool
+	Type      string
+	Debug     bool
+	Trace     bool
+	TraceMode string
+	TraceType string
 }
 
 // DistroInfo stores host operating system distribution details.
@@ -321,6 +324,9 @@ func getAgentInfo(config oci.RuntimeConfig) (AgentInfo, error) {
 			return AgentInfo{}, errors.New("cannot determine Kata agent config")
 		}
 		agent.Debug = agentConfig.Debug
+		agent.Trace = agentConfig.Trace
+		agent.TraceMode = agentConfig.TraceMode
+		agent.TraceType = agentConfig.TraceType
 	default:
 		// Nothing useful to report for the other agent types
 	}

diff --git a/cli/kata-env_test.go b/cli/kata-env_test.go
@@ -43,6 +43,7 @@ var (
 	shimDebug       = false
 	netmonDebug     = false
 	agentDebug      = false
+	agentTrace      = false
 )
 
 // makeVersionBinary creates a shell script with the specified file
@@ -155,6 +156,7 @@ func makeRuntimeConfig(prefixDir string) (configFile string, config oci.RuntimeC
 		ShimDebug:            shimDebug,
 		NetmonDebug:          netmonDebug,
 		AgentDebug:           agentDebug,
+		AgentTrace:           agentTrace,
 	}
 
 	runtimeConfig := katatestutils.MakeRuntimeConfigFileData(configFileOptions)
@@ -217,6 +219,11 @@ func getExpectedAgentDetails(config oci.RuntimeConfig) (AgentInfo, error) {
 	return AgentInfo{
 		Type:  string(config.AgentType),
 		Debug: agentConfig.Debug,
+		Trace: agentConfig.Trace,
+
+		// No trace mode/type set by default
+		TraceMode: "",
+		TraceType: "",
 	}, nil
 }
 
@@ -496,6 +503,7 @@ func TestEnvGetEnvInfo(t *testing.T) {
 		runtimeTrace = toggle
 		shimDebug = toggle
 		agentDebug = toggle
+		agentTrace = toggle
 
 		configFile, config, err := makeRuntimeConfig(tmpdir)
 		assert.NoError(t, err)
@@ -823,6 +831,16 @@ func TestEnvGetAgentInfo(t *testing.T) {
 	assert.NoError(t, err)
 	assert.True(t, agent.Debug)
 
+	agentConfig.Trace = true
+	agentConfig.TraceMode = "traceMode"
+	agentConfig.TraceType = "traceType"
+	config.AgentConfig = agentConfig
+	agent, err = getAgentInfo(config)
+	assert.NoError(t, err)
+	assert.True(t, agent.Trace)
+	assert.Equal(t, agent.TraceMode, "traceMode")
+	assert.Equal(t, agent.TraceType, "traceType")
+
 	config.AgentConfig = "I am the wrong type"
 	_, err = getAgentInfo(config)
 	assert.Error(t, err)

diff --git a/pkg/katautils/config.go b/pkg/katautils/config.go
@@ -138,7 +138,10 @@ type shim struct {
 }
 
 type agent struct {
-	Debug bool `toml:"enable_debug"`
+	Debug     bool   `toml:"enable_debug"`
+	Tracing   bool   `toml:"enable_tracing"`
+	TraceMode string `toml:"trace_mode"`
+	TraceType string `toml:"trace_type"`
 }
 
 type netmon struct {
@@ -395,6 +398,18 @@ func (a agent) debug() bool {
 	return a.Debug
 }
 
+func (a agent) trace() bool {
+	return a.Tracing
+}
+
+func (a agent) traceMode() string {
+	return a.TraceMode
+}
+
+func (a agent) traceType() string {
+	return a.TraceType
+}
+
 func (n netmon) enable() bool {
 	return n.Enable
 }
@@ -655,8 +670,11 @@ func updateRuntimeConfigAgent(configPath string, tomlConf tomlConfig, config *oc
 		case kataAgentTableType:
 			config.AgentType = vc.KataContainersAgent
 			config.AgentConfig = vc.KataAgentConfig{
-				UseVSock: config.HypervisorConfig.UseVSock,
-				Debug:    agent.debug(),
+				UseVSock:  config.HypervisorConfig.UseVSock,
+				Debug:     agent.debug(),
+				Trace:     agent.trace(),
+				TraceMode: agent.traceMode(),
+				TraceType: agent.traceType(),
 			}
 		}
 	}
@@ -717,6 +735,11 @@ func SetKernelParams(runtimeConfig *oci.RuntimeConfig) error {
 
 	// next, check for agent specific kernel params
 	if agentConfig, ok := runtimeConfig.AgentConfig.(vc.KataAgentConfig); ok {
+		err := vc.KataAgentSetDefaultTraceConfigOptions(&agentConfig)
+		if err != nil {
+			return err
+		}
+
 		params := vc.KataAgentKernelParams(agentConfig)
 
 		for _, p := range params {

diff --git a/pkg/katautils/config_test.go b/pkg/katautils/config_test.go
@@ -34,6 +34,7 @@ var (
 	shimDebug       = false
 	netmonDebug     = false
 	agentDebug      = false
+	agentTrace      = false
 )
 
 type testRuntimeConfig struct {
@@ -111,6 +112,7 @@ func createAllRuntimeConfigFiles(dir, hypervisor string) (config testRuntimeConf
 		ShimDebug:            shimDebug,
 		NetmonDebug:          netmonDebug,
 		AgentDebug:           agentDebug,
+		AgentTrace:           agentTrace,
 	}
 
 	runtimeConfigFileData := katatestutils.MakeRuntimeConfigFileData(configFileOptions)
@@ -1206,6 +1208,14 @@ func TestAgentDefaults(t *testing.T) {
 
 	a.Debug = true
 	assert.Equal(a.debug(), a.Debug)
+
+	assert.Equal(a.trace(), a.Tracing)
+
+	a.Tracing = true
+	assert.Equal(a.trace(), a.Tracing)
+
+	assert.Equal(a.traceMode(), a.TraceMode)
+	assert.Equal(a.traceType(), a.TraceType)
 }
 
 func TestGetDefaultConfigFilePaths(t *testing.T) {

diff --git a/virtcontainers/agent.go b/virtcontainers/agent.go
@@ -133,7 +133,7 @@ type agent interface {
 	// init().
 	// After init() is called, agent implementations should be initialized and ready
 	// to handle all other Agent interface methods.
-	init(ctx context.Context, sandbox *Sandbox, config interface{}) error
+	init(ctx context.Context, sandbox *Sandbox, config interface{}) (disableVMShutdown bool, err error)
 
 	// capabilities should return a structure that specifies the capabilities
 	// supported by the agent.

diff --git a/virtcontainers/hyperstart_agent.go b/virtcontainers/hyperstart_agent.go
@@ -264,7 +264,7 @@ func fsMapFromDevices(c *Container) ([]*hyperstart.FsmapDescriptor, error) {
 }
 
 // init is the agent initialization implementation for hyperstart.
-func (h *hyper) init(ctx context.Context, sandbox *Sandbox, config interface{}) (err error) {
+func (h *hyper) init(ctx context.Context, sandbox *Sandbox, config interface{}) (disableVMShutdown bool, err error) {
 	// save
 	h.ctx = ctx
 
@@ -276,25 +276,25 @@ func (h *hyper) init(ctx context.Context, sandbox *Sandbox, config interface{})
 
 		h.sandbox = sandbox
 	default:
-		return errInvalidConfigType
+		return false, errInvalidConfigType
 	}
 
 	h.proxy, err = newProxy(sandbox.config.ProxyType)
 	if err != nil {
-		return err
+		return false, err
 	}
 
 	h.shim, err = newShim(sandbox.config.ShimType)
 	if err != nil {
-		return err
+		return false, err
 	}
 
 	// Fetch agent runtime info.
 	if err := sandbox.store.Load(store.Agent, &h.state); err != nil {
 		h.Logger().Debug("Could not retrieve anything from storage")
 	}
 
-	return nil
+	return false, nil
 }
 
 func (h *hyper) getVMPath(id string) string {