Add build tracing

This creates a rotating build.trace.gz in the out directory that can be
loaded with chrome://tracing. It'll include start and end timings for
make/soong/kati/ninja, and it will import and time-correct the ninja log
files.

Test: m -j; load out/build.trace.gz in chrome://tracing
Test: multiproduct_kati -keep; load out/multiproduct*/build.trace.gz
Change-Id: Ic060fa9515eb88d95dbe16712479dae9dffcf626

1 files changed, 23 insertions, 0 deletions

diff --git a/ui/tracer/Android.bp b/ui/tracer/Android.bp
new file mode 100644
index 000000000..89812a137
--- /dev/null
+++ b/ui/tracer/Android.bp
@@ -0,0 +1,23 @@
+// Copyright 2016 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+bootstrap_go_package {
+    name: "soong-ui-tracer",
+    pkgPath: "android/soong/ui/tracer",
+    deps: ["soong-ui-logger"],
+    srcs: [
+        "ninja.go",
+        "tracer.go",
+    ],
+}