Add UMA field for app CPU architecture

Bug: 1164487
Change-Id: I7a2fbfd53d7321b3fead090ead52f1de699f53af
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2631428Reviewed-by: Mark Mentovai <mark@chromium.org>
Reviewed-by: Alexei Svitkine <asvitkine@chromium.org>
Commit-Queue: Mark Mentovai <mark@chromium.org>
Auto-Submit: Avi Drissman <avi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#845746}

base/system/sys_info.cc

@@ -114,4 +114,19 @@ base::TimeDelta SysInfo::Uptime() {
   return base::TimeDelta::FromMicroseconds(uptime_in_microseconds);
 }
 
+// static
+std::string SysInfo::ProcessCPUArchitecture() {
+#if defined(ARCH_CPU_X86)
+  return "x86";
+#elif defined(ARCH_CPU_X86_64)
+  return "x86_64";
+#elif defined(ARCH_CPU_ARMEL)
+  return "ARM";
+#elif defined(ARCH_CPU_ARM64)
+  return "ARM_64";
+#else
+  return std::string();
+#endif
+}
+
 }  // namespace base

base/system/sys_info.h

@@ -114,6 +114,13 @@ class BASE_EXPORT SysInfo {
   //      whereas a x86-64 kernel on the same CPU will return "x86_64"
   static std::string OperatingSystemArchitecture();
 
+  // Returns the architecture of the running process, which might be different
+  // than the architecture returned by OperatingSystemArchitecture() (e.g.
+  // macOS Rosetta, a 32-bit binary on a 64-bit OS, etc).
+  // Will return one of: "x86", "x86_64", "ARM", "ARM_64", or an empty string if
+  // none of the above.
+  static std::string ProcessCPUArchitecture();
+
   // Avoid using this. Use base/cpu.h to get information about the CPU instead.
   // http://crbug.com/148884
   // Returns the CPU model name of the system. If it can not be figured out,

components/metrics/metrics_log.cc

@@ -216,6 +216,9 @@ void MetricsLog::RecordCoreSystemProfile(
   // crbug.com/370104 for details.
   hardware->set_cpu_architecture(base::SysInfo::OperatingSystemArchitecture());
 #endif
+  auto app_os_arch = base::SysInfo::ProcessCPUArchitecture();
+  if (!app_os_arch.empty())
+    hardware->set_app_cpu_architecture(app_os_arch);
   hardware->set_system_ram_mb(base::SysInfo::AmountOfPhysicalMemoryMB());
   hardware->set_hardware_class(base::SysInfo::HardwareModelName());
 #if defined(OS_WIN)

components/metrics/metrics_log_unittest.cc

@@ -181,6 +181,9 @@ TEST_F(MetricsLogTest, BasicRecord) {
 #if !defined(OS_IOS)
   hardware->set_cpu_architecture(base::SysInfo::OperatingSystemArchitecture());
 #endif
+  auto app_os_arch = base::SysInfo::ProcessCPUArchitecture();
+  if (!app_os_arch.empty())
+    hardware->set_app_cpu_architecture(app_os_arch);
   hardware->set_system_ram_mb(base::SysInfo::AmountOfPhysicalMemoryMB());
   hardware->set_hardware_class(GetExpectedHardwareClass());
 #if defined(OS_WIN)

third_party/metrics_proto/README.chromium

 Name: Metrics Protos
 Short Name: metrics_proto
 URL: This is the canonical public repository
-Version: 351916971
-Date: 2021/01/15 UTC
+Version: 352604480
+Date: 2021/01/19 UTC
 License: BSD
 Security Critical: Yes
 

third_party/metrics_proto/system_profile.proto

@@ -147,13 +147,19 @@ message SystemProfileProto {
   optional OS os = 5;
 
   // Information on the user's hardware.
-  // Next tag: 21
+  // Next tag: 22
   message Hardware {
-    // CPU architecture. Taken from uname -m and modified in Chromium logic.
+    // OS CPU architecture. Taken from uname -m and modified in Chromium logic.
     // Common options are: x86, x86_64, armv7l, armv8l, aarch64.
     // Not recorded on iOS.
     optional string cpu_architecture = 1;
 
+    // Browser process CPU architecture. Will be different from
+    // `cpu_architecture` in the case where Chromium runs non-natively (e.g.
+    // macOS Rosetta or Arm Windows). One of four values: x86, x86_64, ARM,
+    // ARM_64. Added in M90.
+    optional string app_cpu_architecture = 21;
+
     // The amount of RAM present on the system, in megabytes.
     optional int64 system_ram_mb = 2;