component updater: report error code and mount time to UMA

New metric - ComponentUpdater.CROS.Result: track the chrome os installer result (error code, etc.).
New metric - ComponentUpdater.CROS.MountTime: track time to mount a component image.

BUG=chromium:793052
TEST=platform_AddPrinter.epson

Change-Id: I502e1983adcacb488877e83723cc91b6ee504312
Reviewed-on: https://chromium-review.googlesource.com/963182
Commit-Queue: Xiaochu Liu <xiaochu@chromium.org>
Reviewed-by: Alexei Svitkine <asvitkine@chromium.org>
Reviewed-by: Dan Erat <derat@chromium.org>
Reviewed-by: Joshua Pawlicki <waffles@chromium.org>
Reviewed-by: Sorin Jianu <sorin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#548480}

chrome/browser/chromeos/dbus/chrome_component_updater_service_provider_delegate.cc

@@ -26,6 +26,8 @@ std::string ErrorToString(
     case component_updater::CrOSComponentManager::Error::
         COMPATIBILITY_CHECK_FAILED:
       return "COMPATIBILITY_CHECK_FAILED";
+    case component_updater::CrOSComponentManager::Error::ERROR_MAX:
+      return "ERROR_MAX";
   }
   return "Unknown error code";
 }

chrome/browser/component_updater/cros_component_installer.cc

@@ -8,6 +8,7 @@
 #include <utility>
 
 #include "base/files/file_util.h"
+#include "base/metrics/histogram_macros.h"
 #include "base/path_service.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/task_scheduler/post_task.h"
@@ -86,6 +87,13 @@ std::vector<ComponentConfig> GetInstalled() {
   return configs;
 }
 
+// Report Error code.
+CrOSComponentManager::Error ReportError(CrOSComponentManager::Error error) {
+  UMA_HISTOGRAM_ENUMERATION("ComponentUpdater.ChromeOS.InstallResult", error,
+                            CrOSComponentManager::Error::ERROR_MAX);
+  return error;
+}
+
 }  // namespace
 
 CrOSComponentInstallerPolicy::CrOSComponentInstallerPolicy(
@@ -202,8 +210,9 @@ void CrOSComponentManager::Load(const std::string& name,
     LoadInternal(name, std::move(load_callback));
   } else {
     // A compatible component is installed, do not load it.
-    base::PostTask(FROM_HERE, base::BindOnce(std::move(load_callback),
-                                             Error::NONE, base::FilePath()));
+    base::PostTask(FROM_HERE,
+                   base::BindOnce(std::move(load_callback),
+                                  ReportError(Error::NONE), base::FilePath()));
   }
 }
 
@@ -259,7 +268,8 @@ void CrOSComponentManager::Install(ComponentUpdateService* cus,
   if (!config) {
     base::PostTask(FROM_HERE,
                    base::BindOnce(std::move(load_callback),
-                                  Error::UNKNOWN_COMPONENT, base::FilePath()));
+                                  ReportError(Error::UNKNOWN_COMPONENT),
+                                  base::FilePath()));
     return;
   }
   Register(
@@ -283,14 +293,16 @@ void CrOSComponentManager::FinishInstall(const std::string& name,
                                          LoadCallback load_callback,
                                          update_client::Error error) {
   if (error != update_client::Error::NONE) {
-    base::PostTask(FROM_HERE,
-                   base::BindOnce(std::move(load_callback),
-                                  Error::INSTALL_FAILURE, base::FilePath()));
+    base::PostTask(
+        FROM_HERE,
+        base::BindOnce(std::move(load_callback),
+                       ReportError(Error::INSTALL_FAILURE), base::FilePath()));
   } else if (mount_policy == MountPolicy::kMount) {
     LoadInternal(name, std::move(load_callback));
   } else {
-    base::PostTask(FROM_HERE, base::BindOnce(std::move(load_callback),
-                                             Error::NONE, base::FilePath()));
+    base::PostTask(FROM_HERE,
+                   base::BindOnce(std::move(load_callback),
+                                  ReportError(Error::NONE), base::FilePath()));
   }
 }
 
@@ -305,23 +317,31 @@ void CrOSComponentManager::LoadInternal(const std::string& name,
         ->LoadComponentAtPath(
             name, path,
             base::BindOnce(&CrOSComponentManager::FinishLoad,
-                           base::Unretained(this), std::move(load_callback)));
+                           base::Unretained(this), std::move(load_callback),
+                           base::TimeTicks::Now()));
   } else {
-    base::PostTask(FROM_HERE, base::BindOnce(std::move(load_callback),
-                                             Error::COMPATIBILITY_CHECK_FAILED,
-                                             base::FilePath()));
+    base::PostTask(
+        FROM_HERE,
+        base::BindOnce(std::move(load_callback),
+                       ReportError(Error::COMPATIBILITY_CHECK_FAILED),
+                       base::FilePath()));
   }
 }
 
 void CrOSComponentManager::FinishLoad(LoadCallback load_callback,
+                                      const base::TimeTicks start_time,
                                       base::Optional<base::FilePath> result) {
+  // Report component image mount time.
+  UMA_HISTOGRAM_LONG_TIMES("ComponentUpdater.ChromeOS.MountTime",
+                           base::TimeTicks::Now() - start_time);
   if (!result.has_value()) {
+    base::PostTask(FROM_HERE, base::BindOnce(std::move(load_callback),
+                                             ReportError(Error::MOUNT_FAILURE),
+                                             base::FilePath()));
+  } else {
     base::PostTask(FROM_HERE,
                    base::BindOnce(std::move(load_callback),
-                                  Error::MOUNT_FAILURE, base::FilePath()));
-  } else {
-    base::PostTask(FROM_HERE, base::BindOnce(std::move(load_callback),
-                                             Error::NONE, result.value()));
+                                  ReportError(Error::NONE), result.value()));
   }
 }
 

chrome/browser/component_updater/cros_component_installer.h

@@ -68,12 +68,15 @@ class CrOSComponentInstallerPolicy : public ComponentInstallerPolicy {
 // This class contains functions used to register and install a component.
 class CrOSComponentManager {
  public:
+  // Error needs to be consistent with CrosComponentManagerError in
+  // src/tools/metrics/histograms/enums.xml.
   enum class Error {
     NONE = 0,
     UNKNOWN_COMPONENT = 1,  // Component requested does not exist.
     INSTALL_FAILURE = 2,    // update_client fails to install component.
     MOUNT_FAILURE = 3,      // Component can not be mounted.
     COMPATIBILITY_CHECK_FAILED = 4,  // Compatibility check failed.
+    ERROR_MAX
   };
   using LoadCallback =
       base::OnceCallback<void(Error error, const base::FilePath&)>;
@@ -146,6 +149,7 @@ class CrOSComponentManager {
   // Calls load_callback and pass in the parameter |result| (component mount
   // point).
   void FinishLoad(LoadCallback load_callback,
+                  const base::TimeTicks start_time,
                   base::Optional<base::FilePath> result);
 
   // Registers component |configs| to be updated.

tools/metrics/histograms/enums.xml

@@ -7737,6 +7737,14 @@ Called by update_net_error_codes.py.-->
   <int value="3" label="User disabled"/>
 </enum>
 
+<enum name="CrosComponentManagerError">
+  <int value="0" label="NONE"/>
+  <int value="1" label="UNKNOWN_COMPONENT"/>
+  <int value="2" label="INSTALL_FAILURE"/>
+  <int value="3" label="MOUNT_FAILURE"/>
+  <int value="4" label="COMPATIBILITY_CHECK_FAILED"/>
+</enum>
+
 <enum name="CrosDisksArchiveType">
   <int value="0" label="Unknown"/>
   <int value="1" label="ZIP"/>

tools/metrics/histograms/histograms.xml

@@ -10943,6 +10943,19 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="ComponentUpdater.ChromeOS.InstallResult"
+    enum="CrosComponentManagerError">
+  <owner>xiaochu@chromium.org</owner>
+  <summary>
+    Chrome OS only. Installation error code in CrosComponentManager.
+  </summary>
+</histogram>
+
+<histogram name="ComponentUpdater.ChromeOS.MountTime" units="ms">
+  <owner>xiaochu@chromium.org</owner>
+  <summary>Chrome OS only. Time it takes to mount a component image.</summary>
+</histogram>
+
 <histogram name="ComponentUpdater.UpdateCompleteResult" enum="BooleanError">
   <owner>sorin@chromium.org</owner>
   <summary>The result of an install or an update check.</summary>