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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
/**
* This module is for instrumenting your Talos test for
* performance profiles while running within the parent process.
* Almost all of the functions that this script exposes to the
* Gecko Profiler are synchronous, except for finishTest, since that
* involves requesting the profiles from any content processes and
* then writing to disk.
*
* If your test is running in the content process, you should use the
* TalosContentProfiler.js utility script instead.
*/
export const TalosParentProfiler = {
// Whether or not this TalosContentProfiler object has had initFromObject
// or initFromURLQueryParams called on it. Any functions that change the
// state of the Gecko Profiler should only be called after calling either
// initFromObject or initFromURLQueryParams.
initted: false,
// The subtest name that beginTest() was called with.
currentTest: "unknown",
// Profiler settings.
interval: undefined,
entries: undefined,
featuresArray: undefined,
threadsArray: undefined,
profileDir: undefined,
get TalosPowers() {
// Use a bit of XPCOM hackery to get at the Talos Powers service
// implementation...
return Cc["@mozilla.org/talos/talos-powers-service;1"].getService(
Ci.nsISupports
).wrappedJSObject;
},
/**
* Initialize the profiler using profiler settings supplied in a JS object.
*
* @param obj (object)
* The following properties on the object are respected:
* gecko_profile_interval (int)
* gecko_profile_entries (int)
* gecko_profile_features (string, comma separated list of features to enable)
* gecko_profile_threads (string, comma separated list of threads to filter with)
* gecko_profile_dir (string)
*/
initFromObject(obj = {}) {
if (!this.initted) {
if (
"gecko_profile_dir" in obj &&
typeof obj.gecko_profile_dir == "string" &&
"gecko_profile_interval" in obj &&
Number.isFinite(obj.gecko_profile_interval * 1) &&
"gecko_profile_entries" in obj &&
Number.isFinite(obj.gecko_profile_entries * 1) &&
"gecko_profile_features" in obj &&
typeof obj.gecko_profile_features == "string" &&
"gecko_profile_threads" in obj &&
typeof obj.gecko_profile_threads == "string"
) {
this.interval = obj.gecko_profile_interval;
this.entries = obj.gecko_profile_entries;
this.featuresArray = obj.gecko_profile_features.split(",");
this.threadsArray = obj.gecko_profile_threads.split(",");
this.profileDir = obj.gecko_profile_dir;
this.initted = true;
} else {
console.error(
"Profiler could not init with object: " + JSON.stringify(obj)
);
}
}
},
/**
* Initialize the profiler using a string from a location string.
*
* @param locationSearch (string)
* The location string to initialize with.
*/
initFromURLQueryParams(locationSearch) {
this.initFromObject(this.searchToObject(locationSearch));
},
/**
* Parses an url query string into a JS object.
*
* @param locationSearch (string)
* The location string to parse.
* @returns Object
* The GET params from the location string as
* key-value pairs in the Object.
*/
searchToObject(locationSearch) {
let pairs = locationSearch.substring(1).split("&");
let result = {};
for (let i in pairs) {
if (pairs[i] !== "") {
let pair = pairs[i].split("=");
result[decodeURIComponent(pair[0])] = decodeURIComponent(pair[1] || "");
}
}
return result;
},
/**
* A Talos test is about to start.
*
* @param testName (string)
* The name of the test to use in Profiler markers.
*/
beginTest(testName) {
if (this.initted) {
this.currentTest = testName;
this.TalosPowers.profilerBegin({
entries: this.entries,
interval: this.interval,
featuresArray: this.featuresArray,
threadsArray: this.threadsArray,
});
} else {
let msg =
"You should not call beginTest without having first " +
"initted the Profiler";
console.error(msg);
}
},
/**
* A Talos test has finished. This will stop the Gecko Profiler from
* sampling, and return a Promise that resolves once the Profiler has
* finished dumping the multi-process profile to disk.
*
* @returns Promise
* Resolves once the profile has been dumped to disk. The test should
* not try to quit the browser until this has resolved.
*/
finishTest() {
if (this.initted) {
let profileFile = `${this.currentTest}.profile`;
return this.TalosPowers.profilerFinish(this.profileDir, profileFile);
}
let msg =
"You should not call finishTest without having first " +
"initted the Profiler";
console.error(msg);
return Promise.reject(msg);
},
/**
* A start-up test has finished. Callers don't need to run beginTest or
* finishTest, but should pause the sampler as soon as possible, and call
* this function to dump the profile.
*
* @returns Promise
* Resolves once the profile has been dumped to disk. The test should
* not try to quit the browser until this has resolved.
*/
finishStartupProfiling() {
if (this.initted) {
let profileFile = "startup.profile";
return this.TalosPowers.profilerFinish(this.profileDir, profileFile);
}
return Promise.resolve();
},
/**
* Set a marker indicating the start of the subtest.
*
*/
subtestStart(marker = "") {
if (this.initted) {
this.TalosPowers.profilerSubtestStart(marker);
}
},
/**
* Set a marker indicating the duration of the subtest.
*
* @param marker (string, optional)
* If non-empty, will set a marker immediately.
* @param startTime (number, optional)
* Start time, used to create an interval profile marker. If
* undefined, a single instance marker will be placed.
*/
subtestEnd(marker = "", startTime = undefined) {
if (this.initted) {
this.TalosPowers.profilerSubtestEnd(marker, startTime);
}
},
/**
* Adds a marker to the profile.
*
* @param marker (string, optional)
* If non-empty, will set a marker immediately.
* @param startTime (number, optional)
* Start time, used to create an interval profile marker. If
* undefined, a single instance marker will be placed.
* @returns Promise
* Resolves once the marker has been set.
*/
mark(marker, startTime = undefined) {
if (this.initted) {
// If marker is omitted, just use the test name
if (!marker) {
marker = this.currentTest;
}
this.TalosPowers.addIntervalMarker(marker, startTime);
}
},
afterProfileGathered() {
if (!this.initted) {
return Promise.resolve();
}
return new Promise(resolve => {
Services.obs.addObserver(function onGathered() {
Services.obs.removeObserver(onGathered, "talos-profile-gathered");
resolve();
}, "talos-profile-gathered");
});
},
};