1 files changed, 216 insertions, 0 deletions
diff --git a/tools/profiler/tests/shared-head.js b/tools/profiler/tests/shared-head.js
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+++ b/tools/profiler/tests/shared-head.js
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+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * This file contains utilities that can be shared between xpcshell tests and mochitests.
+ */
+
+// The marker phases.
+const INSTANT = 0;
+const INTERVAL = 1;
+const INTERVAL_START = 2;
+const INTERVAL_END = 3;
+
+// This Services declaration may shadow another from head.js, so define it as
+// a var rather than a const.
+var { Services } = ChromeUtils.import("resource://gre/modules/Services.jsm");
+
+const defaultSettings = {
+  entries: 8 * 1024 * 1024, // 8M entries = 64MB
+  interval: 1, // ms
+  features: ["threads"],
+  threads: ["GeckoMain"],
+};
+
+function startProfiler(callersSettings) {
+  if (Services.profiler.IsActive()) {
+    throw new Error(
+      "The profiler must not be active before starting it in a test."
+    );
+  }
+  const settings = Object.assign({}, defaultSettings, callersSettings);
+  Services.profiler.StartProfiler(
+    settings.entries,
+    settings.interval,
+    settings.features,
+    settings.threads,
+    0,
+    settings.duration
+  );
+}
+
+/**
+ * This is a helper function be able to run `await wait(500)`. Unfortunately
+ * this is needed as the act of collecting functions relies on the periodic
+ * sampling of the threads. See:
+ * https://bugzilla.mozilla.org/show_bug.cgi?id=1529053
+ *
+ * @param {number} time
+ * @returns {Promise}
+ */
+function wait(time) {
+  return new Promise(resolve => {
+    // eslint-disable-next-line mozilla/no-arbitrary-setTimeout
+    setTimeout(resolve, time);
+  });
+}
+
+/**
+ * Get the payloads of a type recursively, including from all subprocesses.
+ *
+ * @param {Object} profile The gecko profile.
+ * @param {string} type The marker payload type, e.g. "DiskIO".
+ * @param {Array} payloadTarget The recursive list of payloads.
+ * @return {Array} The final payloads.
+ */
+function getPayloadsOfTypeFromAllThreads(profile, type, payloadTarget = []) {
+  for (const { markers } of profile.threads) {
+    for (const markerTuple of markers.data) {
+      const payload = markerTuple[markers.schema.data];
+      if (payload && payload.type === type) {
+        payloadTarget.push(payload);
+      }
+    }
+  }
+
+  for (const subProcess of profile.processes) {
+    getPayloadsOfTypeFromAllThreads(subProcess, type, payloadTarget);
+  }
+
+  return payloadTarget;
+}
+
+/**
+ * Get the payloads of a type from a single thread.
+ *
+ * @param {Object} thread The thread from a profile.
+ * @param {string} type The marker payload type, e.g. "DiskIO".
+ * @return {Array} The payloads.
+ */
+function getPayloadsOfType(thread, type) {
+  const { markers } = thread;
+  const results = [];
+  for (const markerTuple of markers.data) {
+    const payload = markerTuple[markers.schema.data];
+    if (payload && payload.type === type) {
+      results.push(payload);
+    }
+  }
+  return results;
+}
+
+/**
+ * Applies the marker schema to create individual objects for each marker
+ *
+ * @param {Object} thread The thread from a profile.
+ * @return {InflatedMarker[]} The markers.
+ */
+function getInflatedMarkerData(thread) {
+  const { markers, stringTable } = thread;
+  return markers.data.map(markerTuple => {
+    const marker = {};
+    for (const [key, tupleIndex] of Object.entries(markers.schema)) {
+      marker[key] = markerTuple[tupleIndex];
+      if (key === "name") {
+        // Use the string from the string table.
+        marker[key] = stringTable[marker[key]];
+      }
+    }
+    return marker;
+  });
+}
+
+/**
+ * It can be helpful to force the profiler to collect a JavaScript sample. This
+ * function spins on a while loop until at least one more sample is collected.
+ *
+ * @return {number} The index of the collected sample.
+ */
+function captureAtLeastOneJsSample() {
+  function getProfileSampleCount() {
+    const profile = Services.profiler.getProfileData();
+    return profile.threads[0].samples.data.length;
+  }
+
+  const sampleCount = getProfileSampleCount();
+  // Create an infinite loop until a sample has been collected.
+  while (true) {
+    if (sampleCount < getProfileSampleCount()) {
+      return sampleCount;
+    }
+  }
+}
+
+/**
+ * This function pauses the profiler before getting the profile. Then after the
+ * getting the data, the profiler is stopped, and all profiler data is removed.
+ * @returns {Promise<Profile>}
+ */
+async function stopAndGetProfile() {
+  Services.profiler.Pause();
+  const profile = await Services.profiler.getProfileDataAsync();
+  Services.profiler.StopProfiler();
+  return profile;
+}
+
+/**
+ * Verifies that a marker is an interval marker.
+ *
+ * @param {InflatedMarker} marker
+ * @returns {boolean}
+ */
+function isIntervalMarker(inflatedMarker) {
+  return (
+    inflatedMarker.phase === 1 &&
+    typeof inflatedMarker.startTime === "number" &&
+    typeof inflatedMarker.endTime === "number"
+  );
+}
+
+/**
+ * @param {Profile} profile
+ * @returns {Thread[]}
+ */
+function getThreads(profile) {
+  const threads = [];
+
+  function getThreadsRecursive(process) {
+    for (const thread of process.threads) {
+      threads.push(thread);
+    }
+    for (const subprocess of process.processes) {
+      getThreadsRecursive(subprocess);
+    }
+  }
+
+  getThreadsRecursive(profile);
+  return threads;
+}
+
+/**
+ * Find a specific marker schema from any process of a profile.
+ *
+ * @param {Profile} profile
+ * @param {string} name
+ * @returns {MarkerSchema}
+ */
+function getSchema(profile, name) {
+  {
+    const schema = profile.meta.markerSchema.find(s => s.name === name);
+    if (schema) {
+      return schema;
+    }
+  }
+  for (const subprocess of profile.processes) {
+    const schema = subprocess.meta.markerSchema.find(s => s.name === name);
+    if (schema) {
+      return schema;
+    }
+  }
+  console.error("Parent process schema", profile.meta.markerSchema);
+  for (const subprocess of profile.processes) {
+    console.error("Child process schema", subprocess.meta.markerSchema);
+  }
+  throw new Error(`Could not find a schema for "${name}".`);
+}