Merge "Copy soong_build metrics into build.trace.gz" into main

ui/build/config.go

@@ -1529,6 +1529,10 @@ func (c *configImpl) SoongMakeVarsMk() string {
 	return filepath.Join(c.SoongOutDir(), "make_vars-"+c.TargetProduct()+".mk")
 }
 
+func (c *configImpl) SoongBuildMetrics() string {
+	return filepath.Join(c.OutDir(), "soong_build_metrics.pb")
+}
+
 func (c *configImpl) ProductOut() string {
 	return filepath.Join(c.OutDir(), "target", "product", c.TargetDevice())
 }

ui/build/soong.go

@@ -23,9 +23,11 @@ import (
 	"strings"
 	"sync"
 	"sync/atomic"
+	"time"
 
 	"android/soong/bazel"
 	"android/soong/ui/metrics"
+	"android/soong/ui/metrics/metrics_proto"
 	"android/soong/ui/status"
 
 	"android/soong/shared"
@@ -33,6 +35,8 @@ import (
 	"github.com/google/blueprint"
 	"github.com/google/blueprint/bootstrap"
 	"github.com/google/blueprint/microfactory"
+
+	"google.golang.org/protobuf/proto"
 )
 
 const (
@@ -717,8 +721,12 @@ func runSoong(ctx Context, config Config) {
 		targets = append(targets, config.SoongNinjaFile())
 	}
 
+	beforeSoongTimestamp := time.Now()
+
 	ninja(targets...)
 
+	loadSoongBuildMetrics(ctx, config, beforeSoongTimestamp)
+
 	distGzipFile(ctx, config, config.SoongNinjaFile(), "soong")
 	distFile(ctx, config, config.SoongVarsFile(), "soong")
 
@@ -732,6 +740,42 @@ func runSoong(ctx Context, config Config) {
 	}
 }
 
+// loadSoongBuildMetrics reads out/soong_build_metrics.pb if it was generated by soong_build and copies the
+// events stored in it into the soong_ui trace to provide introspection into how long the different phases of
+// soong_build are taking.
+func loadSoongBuildMetrics(ctx Context, config Config, oldTimestamp time.Time) {
+	soongBuildMetricsFile := config.SoongBuildMetrics()
+	if metricsStat, err := os.Stat(soongBuildMetricsFile); err != nil {
+		ctx.Verbosef("Failed to stat %s: %s", soongBuildMetricsFile, err)
+		return
+	} else if !metricsStat.ModTime().After(oldTimestamp) {
+		ctx.Verbosef("%s timestamp not later after running soong, expected %s > %s",
+			soongBuildMetricsFile, metricsStat.ModTime(), oldTimestamp)
+		return
+	}
+
+	metricsData, err := os.ReadFile(config.SoongBuildMetrics())
+	if err != nil {
+		ctx.Verbosef("Failed to read %s: %s", soongBuildMetricsFile, err)
+		return
+	}
+
+	soongBuildMetrics := metrics_proto.SoongBuildMetrics{}
+	err = proto.Unmarshal(metricsData, &soongBuildMetrics)
+	if err != nil {
+		ctx.Verbosef("Failed to unmarshal %s: %s", soongBuildMetricsFile, err)
+		return
+	}
+	for _, event := range soongBuildMetrics.Events {
+		desc := event.GetDescription()
+		if dot := strings.LastIndexByte(desc, '.'); dot >= 0 {
+			desc = desc[dot+1:]
+		}
+		ctx.Tracer.Complete(desc, ctx.Thread,
+			event.GetStartTime(), event.GetStartTime()+event.GetRealTime())
+	}
+}
+
 func runMicrofactory(ctx Context, config Config, name string, pkg string, mapping map[string]string) {
 	ctx.BeginTrace(metrics.RunSoong, name)
 	defer ctx.EndTrace()