Move code to read macOS resource coalition stats to //components/power_metrics.

This allows reuse by the code that records histograms in Chrome and
the "power_sampler" tool in //tools/mac/power.

Bug: 1254332
Change-Id: I6c0d9fcdee9d556b061868a90344843b4e80d587
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3265524
Commit-Queue: François Doray <fdoray@chromium.org>
Reviewed-by: Jochen Eisinger <jochen@chromium.org>
Reviewed-by: Etienne Pierre-Doray <etiennep@chromium.org>
Cr-Commit-Position: refs/heads/main@{#945055}

chrome/browser/BUILD.gn

@@ -5609,7 +5609,6 @@ static_library("browser") {
       "obsolete_system/obsolete_system_mac.cc",
       "password_manager/password_manager_util_mac.h",
       "password_manager/password_manager_util_mac.mm",
-      "performance_monitor/resource_coalition_internal_types_mac.h",
       "performance_monitor/resource_coalition_mac.h",
       "performance_monitor/resource_coalition_mac.mm",
       "platform_util_mac.mm",
@@ -5637,6 +5636,7 @@ static_library("browser") {
       "//chrome/services/mac_notifications/public/mojom",
       "//components/crash/core/app",
       "//components/metal_util",
+      "//components/power_metrics",
       "//components/remote_cocoa/browser:browser",
       "//sandbox/mac:seatbelt",
       "//sandbox/policy",

chrome/browser/performance_monitor/resource_coalition_mac.mm

@@ -14,16 +14,46 @@
 #include "base/process/process_handle.h"
 #include "base/strings/sys_string_conversions.h"
 #include "base/time/time.h"
-#include "chrome/browser/performance_monitor/resource_coalition_internal_types_mac.h"
-
-extern "C" int coalition_info_resource_usage(
-    uint64_t cid,
-    struct coalition_resource_usage* cru,
-    size_t sz);
+#include "components/power_metrics/resource_coalition_mac.h"
 
 namespace performance_monitor {
 namespace {
 
+static_assert(
+    THREAD_QOS_DEFAULT ==
+        static_cast<int>(
+            performance_monitor::ResourceCoalition::QoSLevels::kDefault),
+    "QoSLevels indexes should match the OS defined ones.");
+static_assert(
+    THREAD_QOS_MAINTENANCE ==
+        static_cast<int>(
+            performance_monitor::ResourceCoalition::QoSLevels::kMaintenance),
+    "QoSLevels indexes should match the OS defined ones.");
+static_assert(
+    THREAD_QOS_BACKGROUND ==
+        static_cast<int>(
+            performance_monitor::ResourceCoalition::QoSLevels::kBackground),
+    "QoSLevels indexes should match the OS defined ones.");
+static_assert(
+    THREAD_QOS_UTILITY ==
+        static_cast<int>(
+            performance_monitor::ResourceCoalition::QoSLevels::kUtility),
+    "QoSLevels indexes should match the OS defined ones.");
+static_assert(
+    THREAD_QOS_LEGACY ==
+        static_cast<int>(
+            performance_monitor::ResourceCoalition::QoSLevels::kLegacy),
+    "QoSLevels indexes should match the OS defined ones.");
+static_assert(
+    THREAD_QOS_USER_INITIATED ==
+        static_cast<int>(
+            performance_monitor::ResourceCoalition::QoSLevels::kUserInitiated),
+    "QoSLevels indexes should match the OS defined ones.");
+static_assert(THREAD_QOS_USER_INTERACTIVE ==
+                  static_cast<int>(performance_monitor::ResourceCoalition::
+                                       QoSLevels::kUserInteractive),
+              "QoSLevels indexes should match the OS defined ones.");
+
 const char kCoalitionAvailabilityHistogram[] =
     "PerformanceMonitor.ResourceCoalition.Availability";
 
@@ -40,19 +70,6 @@ enum class CoalitionAvailability {
   kMaxValue = kNotAloneInCoalition
 };
 
-// Returns the coalition ID that a given process belongs to, or nullopt if this
-// information isn't available.
-absl::optional<uint64_t> GetProcessCoalitionId(const base::ProcessId pid) {
-  proc_pidcoalitioninfo coalition_info = {};
-  int res = proc_pidinfo(pid, PROC_PIDCOALITIONINFO, 0, &coalition_info,
-                         sizeof(coalition_info));
-
-  if (res != sizeof(coalition_info))
-    return absl::nullopt;
-
-  return coalition_info.coalition_id[COALITION_TYPE_RESOURCE];
-}
-
 // Returns the coalition ID that the current process belongs to. If this isn't
 // available or deemed not usable (e.g. if the process is not alone in its
 // coalition) this will return nullopt and |availability_details| will receive
@@ -61,7 +78,7 @@ absl::optional<uint64_t> GetProcessCoalitionId(const base::ProcessId pid) {
 absl::optional<uint64_t> GetCurrentCoalitionId(
     CoalitionAvailability* availability_details) {
   DCHECK(availability_details);
-  auto cid = GetProcessCoalitionId(base::GetCurrentProcId());
+  auto cid = power_metrics::GetProcessCoalitionId(base::GetCurrentProcId());
 
   if (!cid.has_value()) {
     *availability_details = CoalitionAvailability::kCoalitionIDNotAvailable;
@@ -69,15 +86,13 @@ absl::optional<uint64_t> GetCurrentCoalitionId(
   }
 
   // Check if resource usage metrics can be retrieved for this coalition ID.
-  coalition_resource_usage cru = {};
-  uint64_t res = coalition_info_resource_usage(cid.value(), &cru, sizeof(cru));
-  if (res != 0) {
+  if (!power_metrics::GetCoalitionResourceUsage(cid.value())) {
     *availability_details =
         CoalitionAvailability::kCoalitionResourceUsageNotAvailable;
     return absl::nullopt;
   }
 
-  auto parent_cid = GetProcessCoalitionId(
+  auto parent_cid = power_metrics::GetProcessCoalitionId(
       base::GetParentProcessId(base::GetCurrentProcessHandle()));
 
   if (!parent_cid.has_value()) {
@@ -97,20 +112,6 @@ absl::optional<uint64_t> GetCurrentCoalitionId(
   return cid;
 }
 
-// Returns the resource usage coalition data for the given coalition ID.
-// This assumes that resource coalition data are always available for a given
-// coalition ID (i.e. the coalition has a lifetime that exceeds the usage of the
-// ID).
-std::unique_ptr<coalition_resource_usage> GetResourceUsageData(
-    int64_t coalition_id) {
-  auto cru = std::make_unique<coalition_resource_usage>();
-  uint64_t res = coalition_info_resource_usage(
-      coalition_id, cru.get(), sizeof(coalition_resource_usage));
-  DCHECK_EQ(0U, res);
-
-  return cru;
-}
-
 NSDictionary* MaybeGetDictionaryFromPath(const base::FilePath& path) {
   // The folder where the energy coefficient plist files are stored.
   NSString* plist_path_string = base::SysUTF8ToNSString(path.value().c_str());
@@ -147,11 +148,13 @@ ResourceCoalition::~ResourceCoalition() = default;
 
 absl::optional<ResourceCoalition::DataRate> ResourceCoalition::GetDataRate() {
   DCHECK(IsAvailable());
-  DCHECK_EQ(GetProcessCoalitionId(base::GetCurrentProcId()).value(),
-            coalition_id_.value());
+  DCHECK_EQ(
+      power_metrics::GetProcessCoalitionId(base::GetCurrentProcId()).value(),
+      coalition_id_.value());
   DCHECK(last_data_sample_);
-  return GetDataRateImpl(GetResourceUsageData(coalition_id_.value()),
-                         base::TimeTicks::Now());
+  return GetDataRateImpl(
+      power_metrics::GetCoalitionResourceUsage(coalition_id_.value()),
+      base::TimeTicks::Now());
 }
 
 absl::optional<ResourceCoalition::DataRate>
@@ -166,7 +169,8 @@ ResourceCoalition::GetDataRateFromFakeDataForTesting(
 }
 
 void ResourceCoalition::SetCoalitionIDToCurrentProcessIdForTesting() {
-  SetCoalitionId(GetProcessCoalitionId(base::GetCurrentProcId()));
+  SetCoalitionId(
+      power_metrics::GetProcessCoalitionId(base::GetCurrentProcId()));
 }
 
 // static
@@ -340,7 +344,8 @@ void ResourceCoalition::EnsureEnergyImpactCoefficientsIfAvailable() {
 void ResourceCoalition::SetCoalitionId(absl::optional<uint64_t> coalition_id) {
   coalition_id_ = coalition_id;
   if (coalition_id_.has_value()) {
-    last_data_sample_ = GetResourceUsageData(coalition_id_.value());
+    last_data_sample_ =
+        power_metrics::GetCoalitionResourceUsage(coalition_id_.value());
     last_data_sample_timestamp_ = base::TimeTicks::Now();
   }
 }

chrome/browser/performance_monitor/resource_coalition_mac_unittest.mm

@@ -18,8 +18,8 @@
 #include "base/strings/string_util.h"
 #include "base/test/metrics/histogram_tester.h"
 #include "base/time/time.h"
-#include "chrome/browser/performance_monitor/resource_coalition_internal_types_mac.h"
 #include "chrome/common/chrome_paths.h"
+#include "components/power_metrics/resource_coalition_internal_types_mac.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace performance_monitor {

chrome/test/BUILD.gn

@@ -5582,6 +5582,7 @@ test("unit_tests") {
       "//chrome/services/mac_notifications/public/mojom",
       "//chrome/utility/safe_browsing/mac",
       "//chrome/utility/safe_browsing/mac:dmg_common",
+      "//components/power_metrics",
       "//ui/events/devices:test_support",
     ]
   }

components/power_metrics/BUILD.gn

@@ -0,0 +1,15 @@
+# Copyright 2021 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+if (is_mac) {
+  static_library("power_metrics") {
+    sources = [
+      "resource_coalition_internal_types_mac.h",
+      "resource_coalition_mac.h",
+      "resource_coalition_mac.mm",
+    ]
+
+    deps = [ "//base" ]
+  }
+}

components/power_metrics/DIR_METADATA

@@ -0,0 +1,12 @@
+# Metadata information for this directory.
+#
+# For more information on DIR_METADATA files, see:
+#   https://source.chromium.org/chromium/infra/infra/+/main:go/src/infra/tools/dirmd/README.md
+#
+# For the schema of this file, see Metadata message:
+#   https://source.chromium.org/chromium/infra/infra/+/main:go/src/infra/tools/dirmd/proto/dir_metadata.proto
+
+monorail {
+  component: "Internals>Power"
+}
+team_email: "chrome-catan-battery@google.com"

components/power_metrics/OWNERS

@@ -0,0 +1,2 @@
+etiennep@chromium.org
+fdoray@chromium.org

components/power_metrics/resource_coalition_internal_types_mac.h

@@ -2,17 +2,14 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// This file defines some data types used to retrieve the coalition data from
-// the OS. It's only meant to be included in resource_coalition_mac.h and its
-// test files.
+// This file defines data types used to retrieve coalition metrics from the OS.
 
-#ifndef CHROME_BROWSER_PERFORMANCE_MONITOR_RESOURCE_COALITION_INTERNAL_TYPES_MAC_H_
-#define CHROME_BROWSER_PERFORMANCE_MONITOR_RESOURCE_COALITION_INTERNAL_TYPES_MAC_H_
+#ifndef COMPONENTS_POWER_METRICS_RESOURCE_COALITION_INTERNAL_TYPES_MAC_H_
+#define COMPONENTS_POWER_METRICS_RESOURCE_COALITION_INTERNAL_TYPES_MAC_H_
 
-#include "chrome/browser/performance_monitor/resource_coalition_mac.h"
+#include <stdint.h>
 
 // Comes from osfmk/mach/coalition.h
-
 #define COALITION_TYPE_RESOURCE (0)
 #define COALITION_TYPE_JETSAM (1)
 #define COALITION_TYPE_MAX (1)
@@ -36,45 +33,7 @@
 static_assert(COALITION_NUM_THREAD_QOS_TYPES == THREAD_QOS_LAST,
               "Unexpected number of QoS levels.");
 
-static_assert(
-    THREAD_QOS_DEFAULT ==
-        static_cast<int>(
-            performance_monitor::ResourceCoalition::QoSLevels::kDefault),
-    "QoSLevels indexes should match the OS defined ones.");
-static_assert(
-    THREAD_QOS_MAINTENANCE ==
-        static_cast<int>(
-            performance_monitor::ResourceCoalition::QoSLevels::kMaintenance),
-    "QoSLevels indexes should match the OS defined ones.");
-static_assert(
-    THREAD_QOS_BACKGROUND ==
-        static_cast<int>(
-            performance_monitor::ResourceCoalition::QoSLevels::kBackground),
-    "QoSLevels indexes should match the OS defined ones.");
-static_assert(
-    THREAD_QOS_UTILITY ==
-        static_cast<int>(
-            performance_monitor::ResourceCoalition::QoSLevels::kUtility),
-    "QoSLevels indexes should match the OS defined ones.");
-static_assert(
-    THREAD_QOS_LEGACY ==
-        static_cast<int>(
-            performance_monitor::ResourceCoalition::QoSLevels::kLegacy),
-    "QoSLevels indexes should match the OS defined ones.");
-static_assert(
-    THREAD_QOS_USER_INITIATED ==
-        static_cast<int>(
-            performance_monitor::ResourceCoalition::QoSLevels::kUserInitiated),
-    "QoSLevels indexes should match the OS defined ones.");
-static_assert(THREAD_QOS_USER_INTERACTIVE ==
-                  static_cast<int>(performance_monitor::ResourceCoalition::
-                                       QoSLevels::kUserInteractive),
-              "QoSLevels indexes should match the OS defined ones.");
-
 // Comes from bsd/sys/coalition.h
-//
-// TODO(crbug.com/1229686): Report some data derived from the tasks_started and
-// tasks_exited counters.
 struct coalition_resource_usage {
   uint64_t tasks_started;
   uint64_t tasks_exited;
@@ -117,4 +76,4 @@ struct proc_pidcoalitioninfo {
 // Comes from bsd/sys/proc_info.h
 #define PROC_PIDCOALITIONINFO 20
 
-#endif  // CHROME_BROWSER_PERFORMANCE_MONITOR_RESOURCE_COALITION_INTERNAL_TYPES_MAC_H_
+#endif  // COMPONENTS_POWER_METRICS_RESOURCE_COALITION_INTERNAL_TYPES_MAC_H_

components/power_metrics/resource_coalition_mac.h

@@ -0,0 +1,34 @@
+// Copyright 2021 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Resource Coalition is an (undocumented) mechanism available in macOS that
+// allows retrieving accrued resource usage metrics for a group of processes,
+// including processes that have died. Typically, a coalition includes a root
+// process and its descendants. The source can help understand the mechanism:
+// https://github.com/apple/darwin-xnu/blob/main/osfmk/kern/coalition.c
+
+#ifndef COMPONENTS_POWER_METRICS_RESOURCE_COALITION_MAC_H_
+#define COMPONENTS_POWER_METRICS_RESOURCE_COALITION_MAC_H_
+
+#include <stdint.h>
+#include <memory>
+
+#include "base/process/process_handle.h"
+#include "components/power_metrics/resource_coalition_internal_types_mac.h"
+#include "third_party/abseil-cpp/absl/types/optional.h"
+
+namespace power_metrics {
+
+// Returns the coalition id for the process identified by |pid| or nullopt if
+// not available.
+absl::optional<uint64_t> GetProcessCoalitionId(base::ProcessId pid);
+
+// Returns resource usage data for the coalition identified by |coalition_id|,
+// or nullptr if not available.
+std::unique_ptr<coalition_resource_usage> GetCoalitionResourceUsage(
+    int64_t coalition_id);
+
+}  // namespace power_metrics
+
+#endif  // COMPONENTS_PPOWER_METRICS_RESOURCE_COALITION_MAC_H_

components/power_metrics/resource_coalition_mac.mm

@@ -0,0 +1,39 @@
+// Copyright 2021 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "components/power_metrics/resource_coalition_mac.h"
+
+#include <libproc.h>
+
+#include "base/check_op.h"
+
+extern "C" int coalition_info_resource_usage(
+    uint64_t cid,
+    struct coalition_resource_usage* cru,
+    size_t sz);
+
+namespace power_metrics {
+
+absl::optional<uint64_t> GetProcessCoalitionId(base::ProcessId pid) {
+  proc_pidcoalitioninfo coalition_info = {};
+  int res = proc_pidinfo(pid, PROC_PIDCOALITIONINFO, 0, &coalition_info,
+                         sizeof(coalition_info));
+
+  if (res != sizeof(coalition_info))
+    return absl::nullopt;
+
+  return coalition_info.coalition_id[COALITION_TYPE_RESOURCE];
+}
+
+std::unique_ptr<coalition_resource_usage> GetCoalitionResourceUsage(
+    int64_t coalition_id) {
+  auto cru = std::make_unique<coalition_resource_usage>();
+  uint64_t res = coalition_info_resource_usage(
+      coalition_id, cru.get(), sizeof(coalition_resource_usage));
+  if (res == 0U)
+    return cru;
+  return nullptr;
+}
+
+}  // power_metrics