pw_perf_test: Reogranize source files

This CL moves `internal::Framework`, `internal::TestInfo`, and `State`
out of pw_perf_test.h and into their own separate files.

It also moves performance_test_generic.cc to
examples/example_perf_test.cc.

Finally, it removes perf_test_test.cc as this file created a no-op unit
test.

Change-Id: Id5e984cdf80bb7ed801be1f81ebb8cba8c05b91b
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/178914
Reviewed-by: Armando Montanez <amontanez@google.com>
Commit-Queue: Aaron Green <aarongreen@google.com>

15 files changed, 588 insertions, 457 deletions

diff --git a/BUILD.gn b/BUILD.gn
index 471aeec9b..6a9a23145 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -646,7 +646,7 @@ if (current_toolchain != default_toolchain) {
   pw_test_group("pw_perf_tests") {
     tests = [
       "$dir_pw_checksum:perf_tests",
-      "$dir_pw_perf_test:perf_test_tests_test",
+      "$dir_pw_perf_test:examples",
       "$dir_pw_protobuf:perf_tests",
     ]
     output_metadata = true
diff --git a/pw_perf_test/BUILD.bazel b/pw_perf_test/BUILD.bazel
index 7b0a8fa11..75998ad69 100644
--- a/pw_perf_test/BUILD.bazel
+++ b/pw_perf_test/BUILD.bazel
@@ -29,47 +29,50 @@ package(default_visibility = ["//visibility:public"])
 licenses(["notice"])
 
 pw_cc_library(
-    name = "duration_unit",
-    hdrs = [
-        "public/pw_perf_test/internal/duration_unit.h",
+    name = "pw_perf_test",
+    srcs = [
+        "framework.cc",
+        "perf_test.cc",
+        "test_info.cc",
     ],
-    includes = ["public"],
-    visibility = ["//visibility:private"],
-)
-
-pw_cc_facade(
-    name = "timer_interface_facade",
     hdrs = [
-        "public/pw_perf_test/internal/timer.h",
+        "public/pw_perf_test/internal/framework.h",
+        "public/pw_perf_test/internal/test_info.h",
+        "public/pw_perf_test/perf_test.h",
     ],
     includes = ["public"],
-    visibility = ["//visibility:private"],
     deps = [
-        ":duration_unit",
+        ":event_handler",
+        ":state",
+        ":timer",
+        "//pw_preprocessor",
     ],
 )
 
 pw_cc_library(
-    name = "timer",
+    name = "state",
+    srcs = [
+        "state.cc",
+    ],
     hdrs = [
-        "public/pw_perf_test/internal/timer.h",
+        "public/pw_perf_test/state.h",
     ],
     includes = ["public"],
     deps = [
-        ":duration_unit",
-        "@pigweed//targets:pw_perf_test_timer_backend",
+        ":event_handler",
+        ":timer",
+        "//pw_assert",
+        "//pw_log",
     ],
 )
 
-pw_cc_library(
-    name = "timer_multiplexer",
-    visibility = ["@pigweed//targets:__pkg__"],
-    deps = select({
-        "//conditions:default": [":chrono_timer"],
-    }),
+pw_cc_test(
+    name = "state_test",
+    srcs = ["state_test.cc"],
+    deps = [":pw_perf_test"],
 )
 
-# EventHandler Configuraitions
+# Event handlers
 
 pw_cc_library(
     name = "event_handler",
@@ -79,19 +82,6 @@ pw_cc_library(
 )
 
 pw_cc_library(
-    name = "pw_perf_test",
-    srcs = ["perf_test.cc"],
-    hdrs = ["public/pw_perf_test/perf_test.h"],
-    includes = ["public"],
-    deps = [
-        ":event_handler",
-        ":timer",
-        "//pw_assert",
-        "//pw_log",
-    ],
-)
-
-pw_cc_library(
     name = "google_test_style_event_strings",
     hdrs = ["public/pw_perf_test/googletest_style_event_handler.h"],
 )
@@ -119,52 +109,61 @@ pw_cc_library(
     ],
 )
 
-pw_cc_perf_test(
-    name = "generic_test",
-    srcs = ["performance_test_generic.cc"],
-)
+# Timer facade
 
-# Test Declarations
+pw_cc_library(
+    name = "duration_unit",
+    hdrs = [
+        "public/pw_perf_test/internal/duration_unit.h",
+    ],
+    includes = ["public"],
+    visibility = ["//visibility:private"],
+)
 
-pw_cc_test(
-    name = "perf_test_test",
-    srcs = ["perf_test_test.cc"],
-    deps = [":pw_perf_test"],
+pw_cc_facade(
+    name = "timer_interface_facade",
+    hdrs = [
+        "public/pw_perf_test/internal/timer.h",
+    ],
+    includes = ["public"],
+    visibility = ["//visibility:private"],
+    deps = [
+        ":duration_unit",
+    ],
 )
 
-pw_cc_test(
-    name = "timer_test",
-    srcs = ["timer_test.cc"],
+pw_cc_library(
+    name = "timer",
+    hdrs = [
+        "public/pw_perf_test/internal/timer.h",
+    ],
+    includes = ["public"],
     deps = [
-        ":timer",
-        "//pw_chrono:system_clock",
-        "//pw_thread:sleep",
+        ":duration_unit",
+        "@pigweed//targets:pw_perf_test_timer_backend",
     ],
 )
 
+pw_cc_library(
+    name = "timer_multiplexer",
+    visibility = ["@pigweed//targets:__pkg__"],
+    deps = select({
+        "//conditions:default": [":chrono_timer"],
+    }),
+)
+
 pw_cc_test(
-    name = "chrono_timer_test",
-    srcs = ["chrono_test.cc"],
+    name = "timer_test",
+    srcs = ["timer_test.cc"],
     deps = [
-        ":chrono_timer",
+        ":timer",
         "//pw_chrono:system_clock",
         "//pw_thread:sleep",
     ],
 )
 
-pw_cc_test(
-    name = "state_test",
-    srcs = ["state_test.cc"],
-    deps = [":pw_perf_test"],
-)
-
-# Bazel does not yet support building docs.
-filegroup(
-    name = "docs",
-    srcs = ["docs.rst"],
-)
+# Chrono timer facade implementation
 
-# Chrono Implementation
 pw_cc_library(
     name = "chrono_timer",
     hdrs = [
@@ -183,7 +182,18 @@ pw_cc_library(
     ],
 )
 
-# ARM Cortex Implementation
+pw_cc_test(
+    name = "chrono_timer_test",
+    srcs = ["chrono_test.cc"],
+    deps = [
+        ":chrono_timer",
+        "//pw_chrono:system_clock",
+        "//pw_thread:sleep",
+    ],
+)
+
+# ARM Cortex timer facade implementation
+
 pw_cc_library(
     name = "arm_cortex_timer",
     hdrs = [
@@ -200,3 +210,16 @@ pw_cc_library(
         ":timer_interface_facade",
     ],
 )
+
+# Module-level targets
+
+pw_cc_perf_test(
+    name = "example_perf_test",
+    srcs = ["examples/example_perf_test.cc"],
+)
+
+# Bazel does not yet support building docs.
+filegroup(
+    name = "docs",
+    srcs = ["docs.rst"],
+)
diff --git a/pw_perf_test/BUILD.gn b/pw_perf_test/BUILD.gn
index 81ee5d930..8772591c4 100644
--- a/pw_perf_test/BUILD.gn
+++ b/pw_perf_test/BUILD.gn
@@ -26,63 +26,51 @@ config("public_include_path") {
   visibility = [ ":*" ]
 }
 
-config("arm_config") {
-  include_dirs = [ "arm_cortex_cyccnt_public_overrides" ]
-  visibility = [ ":*" ]
-}
-
-config("chrono_config") {
-  include_dirs = [ "chrono_public_overrides" ]
-  visibility = [ ":*" ]
-}
-
-pw_test_group("tests") {
-  tests = [
-    ":perf_test_test",
-    ":timer_facade_test",
-    ":chrono_timer_test",
-    ":state_test",
+pw_source_set("pw_perf_test") {
+  public_configs = [ ":public_include_path" ]
+  public = [
+    "public/pw_perf_test/internal/framework.h",
+    "public/pw_perf_test/internal/test_info.h",
+    "public/pw_perf_test/perf_test.h",
+  ]
+  public_deps = [
+    ":event_handler",
+    ":state",
+    ":timer_interface",
+    dir_pw_preprocessor,
+  ]
+  sources = [
+    "framework.cc",
+    "perf_test.cc",
+    "test_info.cc",
   ]
 }
 
-group("perf_test_tests_test") {
-  deps = [ ":generic_perf_test" ]
-}
-
-# Timing interface variables
-
-pw_source_set("duration_unit") {
-  public = [ "public/pw_perf_test/internal/duration_unit.h" ]
+pw_source_set("state") {
   public_configs = [ ":public_include_path" ]
-  visibility = [ ":*" ]
+  public = [ "public/pw_perf_test/state.h" ]
+  public_deps = [
+    ":event_handler",
+    ":timer_interface",
+    dir_pw_assert,
+  ]
+  deps = [ dir_pw_log ]
+  sources = [ "state.cc" ]
 }
 
-pw_facade("timer_interface") {
-  backend = pw_perf_test_TIMER_INTERFACE_BACKEND
-  public = [ "public/pw_perf_test/internal/timer.h" ]
-  public_deps = [ ":duration_unit" ]
-  visibility = [ ":*" ]
+pw_test("state_test") {
+  enable_if = pw_perf_test_TIMER_INTERFACE_BACKEND != ""
+  sources = [ "state_test.cc" ]
+  deps = [ ":state" ]
 }
 
-# Event Handler Configurations
+# Event handlers
 
 pw_source_set("event_handler") {
   public_configs = [ ":public_include_path" ]
   public = [ "public/pw_perf_test/event_handler.h" ]
 }
 
-pw_source_set("pw_perf_test") {
-  public_configs = [ ":public_include_path" ]
-  public = [ "public/pw_perf_test/perf_test.h" ]
-  public_deps = [
-    ":event_handler",
-    ":timer_interface",
-    dir_pw_assert,
-  ]
-  deps = [ dir_pw_log ]
-  sources = [ "perf_test.cc" ]
-}
-
 pw_source_set("googletest_style_event_handler") {
   public_configs = [ ":public_include_path" ]
   public = [ "public/pw_perf_test/googletest_style_event_handler.h" ]
@@ -105,48 +93,34 @@ pw_source_set("log_perf_handler_main") {
   sources = [ "log_perf_handler_main.cc" ]
 }
 
-pw_perf_test("generic_perf_test") {
-  enable_if = pw_perf_test_TIMER_INTERFACE_BACKEND != ""
-  sources = [ "performance_test_generic.cc" ]
-}
+# Timer facade
 
-# Declaring module tests
+pw_source_set("duration_unit") {
+  public = [ "public/pw_perf_test/internal/duration_unit.h" ]
+  public_configs = [ ":public_include_path" ]
+  visibility = [ ":*" ]
+}
 
-pw_test("perf_test_test") {
-  enable_if = pw_perf_test_TIMER_INTERFACE_BACKEND != ""
-  sources = [ "perf_test_test.cc" ]
-  deps = [ ":pw_perf_test" ]
+pw_facade("timer_interface") {
+  backend = pw_perf_test_TIMER_INTERFACE_BACKEND
+  public = [ "public/pw_perf_test/internal/timer.h" ]
+  public_deps = [ ":duration_unit" ]
+  visibility = [ ":*" ]
 }
 
 pw_test("timer_facade_test") {
   enable_if = pw_perf_test_TIMER_INTERFACE_BACKEND != ""
   sources = [ "timer_test.cc" ]
-  public_deps = [ ":timer_interface" ]
-}
-
-pw_test("chrono_timer_test") {
-  enable_if = pw_chrono_SYSTEM_TIMER_BACKEND != ""
-  sources = [ "chrono_test.cc" ]
-  public_deps = [
-    ":chrono_timer",
-    "$dir_pw_chrono:system_timer",
-    "$dir_pw_thread:sleep",
-  ]
-}
-
-pw_test("state_test") {
-  enable_if = pw_perf_test_TIMER_INTERFACE_BACKEND != ""
-  sources = [ "state_test.cc" ]
-  public_deps = [ ":pw_perf_test" ]
+  deps = [ ":timer_interface" ]
 }
 
-# Documentation declaration
+# Chrono timer facade implementation
 
-pw_doc_group("docs") {
-  sources = [ "docs.rst" ]
+config("chrono_config") {
+  include_dirs = [ "chrono_public_overrides" ]
+  visibility = [ ":*" ]
 }
 
-# Chrono Implementation
 pw_source_set("pw_perf_test_chrono") {
   public_configs = [ ":chrono_config" ]
   public = [ "chrono_public_overrides/pw_perf_test_timer_backend/timer.h" ]
@@ -166,7 +140,22 @@ pw_source_set("chrono_timer") {
   visibility = [ ":*" ]
 }
 
-# ARM Cortex Implementation
+pw_test("chrono_timer_test") {
+  enable_if = pw_chrono_SYSTEM_TIMER_BACKEND != ""
+  sources = [ "chrono_test.cc" ]
+  deps = [
+    ":chrono_timer",
+    "$dir_pw_chrono:system_timer",
+    "$dir_pw_thread:sleep",
+  ]
+}
+
+# ARM Cortex timer facade implementation
+
+config("arm_config") {
+  include_dirs = [ "arm_cortex_cyccnt_public_overrides" ]
+  visibility = [ ":*" ]
+}
 
 pw_source_set("arm_cortex_timer") {
   public_configs = [
@@ -185,3 +174,26 @@ pw_source_set("pw_perf_test_arm_cortex") {
   ]
   public_deps = [ ":arm_cortex_timer" ]
 }
+
+# Module-level targets
+
+pw_perf_test("example_perf_test") {
+  enable_if = pw_perf_test_TIMER_INTERFACE_BACKEND != ""
+  sources = [ "examples/example_perf_test.cc" ]
+}
+
+group("examples") {
+  deps = [ ":example_perf_test" ]
+}
+
+pw_test_group("tests") {
+  tests = [
+    ":chrono_timer_test",
+    ":state_test",
+    ":timer_facade_test",
+  ]
+}
+
+pw_doc_group("docs") {
+  sources = [ "docs.rst" ]
+}
diff --git a/pw_perf_test/CMakeLists.txt b/pw_perf_test/CMakeLists.txt
index 80f4487a2..3f5c5c782 100644
--- a/pw_perf_test/CMakeLists.txt
+++ b/pw_perf_test/CMakeLists.txt
@@ -16,44 +16,58 @@ include($ENV{PW_ROOT}/pw_build/pigweed.cmake)
 include($ENV{PW_ROOT}/pw_perf_test/backend.cmake)
 include($ENV{PW_ROOT}/pw_protobuf_compiler/proto.cmake)
 
-pw_add_library(pw_perf_test.duration_unit INTERFACE
-  HEADERS
-    public/pw_perf_test/internal/duration_unit.h
+pw_add_library(pw_perf_test STATIC
   PUBLIC_INCLUDES
     public
-)
-
-pw_add_facade(pw_perf_test.timer INTERFACE
-  BACKEND
-    pw_perf_test.TIMER_INTERFACE_BACKEND
   HEADERS
-    public/pw_perf_test/internal/timer.h
-  PUBLIC_INCLUDES
-    public
+    public/pw_perf_test/internal/framework.h
+    public/pw_perf_test/internal/test_info.h
+    public/pw_perf_test/perf_test.h
   PUBLIC_DEPS
-    pw_perf_test.duration_unit
-)
-
-pw_add_library(pw_perf_test.event_handler INTERFACE
-  HEADERS
-    public/pw_perf_test/event_handler.h
-  PUBLIC_INCLUDES
-    public
+    pw_perf_test.event_handler
+    pw_perf_test.state
+    pw_perf_test.timer
+  SOURCES
+    framework.cc
+    perf_test.cc
+    test_info.cc
 )
 
-pw_add_library(pw_perf_test STATIC
+pw_add_library(pw_perf_test.state STATIC
   PUBLIC_INCLUDES
     public
   HEADERS
-    public/pw_perf_test/perf_test.h
+    public/pw_perf_test/state.h
   PUBLIC_DEPS
     pw_perf_test.timer
     pw_perf_test.event_handler
+    pw_assert
   PRIVATE_DEPS
     pw_log
-    pw_assert
   SOURCES
-    perf_test.cc
+    state.cc
+)
+
+if(NOT "${pw_perf_test.TIMER_INTERFACE_BACKEND}" STREQUAL "")
+  pw_add_test(pw_perf_test.state_test
+    SOURCES
+      state_test.cc
+    PRIVATE_DEPS
+      pw_assert.assert
+      pw_perf_test
+    GROUPS
+      modules
+      pw_perf_test
+  )
+endif()
+
+# Event handlers
+
+pw_add_library(pw_perf_test.event_handler INTERFACE
+  HEADERS
+    public/pw_perf_test/event_handler.h
+  PUBLIC_INCLUDES
+    public
 )
 
 pw_add_library(pw_perf_test.googletest_style_event_handler INTERFACE
@@ -85,15 +99,23 @@ pw_add_library(pw_perf_test.log_perf_handler_main STATIC
     log_perf_handler_main.cc
 )
 
-pw_add_library(pw_perf_test.chrono_timer INTERFACE
+# Timer facade
+
+pw_add_library(pw_perf_test.duration_unit INTERFACE
   HEADERS
-    chrono_public_overrides/pw_perf_test_timer_backend/timer.h
-    public/pw_perf_test/internal/chrono_timer_interface.h
+    public/pw_perf_test/internal/duration_unit.h
+  PUBLIC_INCLUDES
+    public
+)
+
+pw_add_facade(pw_perf_test.timer INTERFACE
+  BACKEND
+    pw_perf_test.TIMER_INTERFACE_BACKEND
+  HEADERS
+    public/pw_perf_test/internal/timer.h
   PUBLIC_INCLUDES
-    chrono_public_overrides
     public
   PUBLIC_DEPS
-    pw_chrono.system_clock
     pw_perf_test.duration_unit
 )
 
@@ -111,6 +133,20 @@ if(NOT "${pw_perf_test.TIMER_INTERFACE_BACKEND}" STREQUAL "")
   )
 endif()
 
+# Chrono timer facade implementation
+
+pw_add_library(pw_perf_test.chrono_timer INTERFACE
+  HEADERS
+    chrono_public_overrides/pw_perf_test_timer_backend/timer.h
+    public/pw_perf_test/internal/chrono_timer_interface.h
+  PUBLIC_INCLUDES
+    chrono_public_overrides
+    public
+  PUBLIC_DEPS
+    pw_chrono.system_clock
+    pw_perf_test.duration_unit
+)
+
 if(NOT "${pw_perf_test.TIMER_INTERFACE_BACKEND}"
     STREQUAL "pw_chrono.SYSTEM_CLOCK_BACKEND.NO_BACKEND_SET")
   pw_add_test(pw_perf_test.chrono_timer_test
@@ -125,29 +161,3 @@ if(NOT "${pw_perf_test.TIMER_INTERFACE_BACKEND}"
       pw_perf_test
   )
 endif()
-
-if(NOT "${pw_perf_test.TIMER_INTERFACE_BACKEND}" STREQUAL "")
-  pw_add_test(pw_perf_test.state_test
-    SOURCES
-      state_test.cc
-    PRIVATE_DEPS
-      pw_assert.assert
-      pw_perf_test
-    GROUPS
-      modules
-      pw_perf_test
-  )
-endif()
-
-if(NOT "${pw_perf_test.TIMER_INTERFACE_BACKEND}" STREQUAL "")
-  pw_add_test(pw_perf_test.perf_test_test
-    SOURCES
-      perf_test_test.cc
-    PRIVATE_DEPS
-      pw_assert.assert
-      pw_perf_test
-    GROUPS
-      modules
-      pw_perf_test
-  )
-endif()
diff --git a/pw_perf_test/performance_test_generic.cc b/pw_perf_test/examples/example_perf_test.cc
index b1318b062..b1318b062 100644
--- a/pw_perf_test/performance_test_generic.cc
+++ b/pw_perf_test/examples/example_perf_test.cc
diff --git a/pw_perf_test/framework.cc b/pw_perf_test/framework.cc
new file mode 100644
index 000000000..ccfc9cc3f
--- /dev/null
+++ b/pw_perf_test/framework.cc
@@ -0,0 +1,53 @@
+// Copyright 2023 The Pigweed Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License"); you may not
+// use this file except in compliance with the License. You may obtain a copy of
+// the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+// License for the specific language governing permissions and limitations under
+// the License.
+
+#include "pw_perf_test/internal/framework.h"
+
+#include "pw_perf_test/internal/test_info.h"
+#include "pw_perf_test/internal/timer.h"
+
+namespace pw::perf_test::internal {
+
+Framework Framework::framework_;
+
+int Framework::RunAllTests() {
+  if (!internal::TimerPrepare()) {
+    return false;
+  }
+
+  event_handler_->RunAllTestsStart(run_info_);
+
+  for (const TestInfo* test = tests_; test != nullptr; test = test->next()) {
+    State test_state = internal::CreateState(
+        kDefaultIterations, *event_handler_, test->test_name());
+    test->Run(test_state);
+  }
+  internal::TimerCleanup();
+  event_handler_->RunAllTestsEnd();
+  return true;
+}
+
+void Framework::RegisterTest(TestInfo& new_test) {
+  ++run_info_.total_tests;
+  if (tests_ == nullptr) {
+    tests_ = &new_test;
+    return;
+  }
+  TestInfo* info = tests_;
+  for (; info->next() != nullptr; info = info->next()) {
+  }
+  info->SetNext(&new_test);
+}
+
+}  // namespace pw::perf_test::internal
diff --git a/pw_perf_test/perf_test.cc b/pw_perf_test/perf_test.cc
index 0e2f8d1ee..3cbe0e2f1 100644
--- a/pw_perf_test/perf_test.cc
+++ b/pw_perf_test/perf_test.cc
@@ -16,89 +16,11 @@
 
 #include "pw_perf_test/perf_test.h"
 
-#include <cstdint>
-
-#include "pw_log/log.h"
 #include "pw_perf_test/event_handler.h"
+#include "pw_perf_test/internal/framework.h"
 #include "pw_perf_test/internal/timer.h"
 
 namespace pw::perf_test {
-namespace internal {
-
-Framework Framework::framework_;
-
-int Framework::RunAllTests() {
-  if (!internal::TimerPrepare()) {
-    return false;
-  }
-
-  event_handler_->RunAllTestsStart(run_info_);
-
-  for (const TestInfo* test = tests_; test != nullptr; test = test->next()) {
-    State test_state =
-        CreateState(kDefaultIterations, *event_handler_, test->test_name());
-    test->Run(test_state);
-  }
-  internal::TimerCleanup();
-  event_handler_->RunAllTestsEnd();
-  return true;
-}
-
-void Framework::RegisterTest(TestInfo& new_test) {
-  ++run_info_.total_tests;
-  if (tests_ == nullptr) {
-    tests_ = &new_test;
-    return;
-  }
-  TestInfo* info = tests_;
-  for (; info->next() != nullptr; info = info->next()) {
-  }
-  info->SetNext(&new_test);
-}
-
-State CreateState(int durations,
-                  EventHandler& event_handler,
-                  const char* test_name) {
-  return State(durations, event_handler, test_name);
-}
-}  // namespace internal
-
-bool State::KeepRunning() {
-  internal::Timestamp iteration_end = internal::GetCurrentTimestamp();
-  if (current_iteration_ == -1) {
-    ++current_iteration_;
-    event_handler_->TestCaseStart(test_info);
-    iteration_start_ = internal::GetCurrentTimestamp();
-    return true;
-  }
-  int64_t duration = internal::GetDuration(iteration_start_, iteration_end);
-  if (duration > max_) {
-    max_ = duration;
-  }
-  if (duration < min_) {
-    min_ = duration;
-  }
-  total_duration_ += duration;
-  ++current_iteration_;
-  PW_LOG_DEBUG("Iteration number: %d - Duration: %ld",
-               current_iteration_,
-               static_cast<long>(duration));
-  event_handler_->TestCaseIteration({current_iteration_, duration});
-  if (current_iteration_ == test_iterations_) {
-    PW_LOG_DEBUG("Total Duration: %ld  Total Iterations: %d",
-                 static_cast<long>(total_duration_),
-                 test_iterations_);
-    mean_ = total_duration_ / test_iterations_;
-    PW_LOG_DEBUG("Mean: %ld: ", static_cast<long>(mean_));
-    PW_LOG_DEBUG("Minimum: %ld", static_cast<long>(min_));
-    PW_LOG_DEBUG("Maxmimum: %ld", static_cast<long>(max_));
-    event_handler_->TestCaseEnd(test_info,
-                                Results{mean_, max_, min_, test_iterations_});
-    return false;
-  }
-  iteration_start_ = internal::GetCurrentTimestamp();
-  return true;
-}
 
 void RunAllTests(EventHandler& handler) {
   internal::Framework::Get().RegisterEventHandler(handler);
diff --git a/pw_perf_test/perf_test_test.cc b/pw_perf_test/perf_test_test.cc
deleted file mode 100644
index 2cdea93e1..000000000
--- a/pw_perf_test/perf_test_test.cc
+++ /dev/null
@@ -1,43 +0,0 @@
-// Copyright 2022 The Pigweed Authors
-//
-// Licensed under the Apache License, Version 2.0 (the "License"); you may not
-// use this file except in compliance with the License. You may obtain a copy of
-// the License at
-//
-//     https://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
-// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
-// License for the specific language governing permissions and limitations under
-// the License.
-
-#include "pw_perf_test/perf_test.h"
-
-#include "gtest/gtest.h"
-
-void TestingFunction(pw::perf_test::State& state) {
-  while (state.KeepRunning()) {
-    // Intentionally empty.
-  }
-}
-
-// This function is intentionally left blank
-void SimpleFunction() {}
-
-void SimpleFunctionWithArgs(int, bool) {}
-
-namespace pw::perf_test {
-namespace {
-
-PW_PERF_TEST(TestingComponentRegistration, TestingFunction);
-
-PW_PERF_TEST_SIMPLE(TestingSimpleRegistration, SimpleFunction);
-
-PW_PERF_TEST_SIMPLE(TestingSimpleRegistrationArgs,
-                    SimpleFunctionWithArgs,
-                    123,
-                    false);
-
-}  // namespace
-}  // namespace pw::perf_test
diff --git a/pw_perf_test/public/pw_perf_test/internal/framework.h b/pw_perf_test/public/pw_perf_test/internal/framework.h
new file mode 100644
index 000000000..bb3ebab22
--- /dev/null
+++ b/pw_perf_test/public/pw_perf_test/internal/framework.h
@@ -0,0 +1,57 @@
+// Copyright 2023 The Pigweed Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License"); you may not
+// use this file except in compliance with the License. You may obtain a copy of
+// the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+// License for the specific language governing permissions and limitations under
+// the License.
+#pragma once
+
+#include "pw_perf_test/event_handler.h"
+
+namespace pw::perf_test::internal {
+
+// Forward declaration.
+class TestInfo;
+
+/// Singleton that manages and runs performance tests.
+///
+/// This class mimics pw::unit_test::Framework.
+class Framework {
+ public:
+  constexpr Framework()
+      : event_handler_(nullptr),
+        tests_(nullptr),
+        run_info_{.total_tests = 0, .default_iterations = kDefaultIterations} {}
+
+  static Framework& Get() { return framework_; }
+
+  void RegisterEventHandler(EventHandler& event_handler) {
+    event_handler_ = &event_handler;
+  }
+
+  void RegisterTest(TestInfo&);
+
+  int RunAllTests();
+
+ private:
+  static constexpr int kDefaultIterations = 10;
+
+  EventHandler* event_handler_;
+
+  // Pointer to the list of tests
+  TestInfo* tests_;
+
+  TestRunInfo run_info_;
+
+  // Singleton
+  static Framework framework_;
+};
+
+}  // namespace pw::perf_test::internal
diff --git a/pw_perf_test/public/pw_perf_test/internal/test_info.h b/pw_perf_test/public/pw_perf_test/internal/test_info.h
new file mode 100644
index 000000000..fd776e9d4
--- /dev/null
+++ b/pw_perf_test/public/pw_perf_test/internal/test_info.h
@@ -0,0 +1,50 @@
+// Copyright 2023 The Pigweed Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License"); you may not
+// use this file except in compliance with the License. You may obtain a copy of
+// the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+// License for the specific language governing permissions and limitations under
+// the License.
+#pragma once
+
+#include "pw_perf_test/state.h"
+
+namespace pw::perf_test::internal {
+
+/// Represents a single test case.
+///
+/// Each instance includes a pointer to a function which constructs and runs the
+/// test class. These are statically allocated instead of the test classes, as
+/// test classes can be very large.
+///
+/// This class mimics pw::unit_test::TestInfo.
+class TestInfo {
+ public:
+  TestInfo(const char* test_name, void (*function_body)(State&));
+
+  // Returns the next registered test
+  TestInfo* next() const { return next_; }
+
+  void SetNext(TestInfo* next) { next_ = next; }
+
+  void Run(State& state) const { run_(state); }
+
+  const char* test_name() const { return test_name_; }
+
+ private:
+  // Function pointer to the code that will be measured
+  void (*run_)(State&);
+
+  // Intrusively linked list, this acts as a pointer to the next test
+  TestInfo* next_ = nullptr;
+
+  const char* test_name_;
+};
+
+}  // namespace pw::perf_test::internal
diff --git a/pw_perf_test/public/pw_perf_test/perf_test.h b/pw_perf_test/public/pw_perf_test/perf_test.h
index e092087f9..90efb0cb0 100644
--- a/pw_perf_test/public/pw_perf_test/perf_test.h
+++ b/pw_perf_test/public/pw_perf_test/perf_test.h
@@ -13,13 +13,9 @@
 // the License.
 #pragma once
 
-#include <cstdint>
-#include <limits>
-
-#include "pw_assert/assert.h"
 #include "pw_perf_test/event_handler.h"
-#include "pw_perf_test/internal/duration_unit.h"
-#include "pw_perf_test/internal/timer.h"
+#include "pw_perf_test/internal/test_info.h"
+#include "pw_perf_test/state.h"
 #include "pw_preprocessor/arguments.h"
 
 #define PW_PERF_TEST(name, function, ...)                             \
@@ -42,137 +38,6 @@
 
 namespace pw::perf_test {
 
-class State;
-
-namespace internal {
-
-class TestInfo;
-
-// Allows access to the private State object constructor
-State CreateState(int durations,
-                  EventHandler& event_handler,
-                  const char* test_name);
-
-class Framework {
- public:
-  constexpr Framework()
-      : event_handler_(nullptr),
-        tests_(nullptr),
-        run_info_{.total_tests = 0, .default_iterations = kDefaultIterations} {}
-
-  static Framework& Get() { return framework_; }
-
-  void RegisterEventHandler(EventHandler& event_handler) {
-    event_handler_ = &event_handler;
-  }
-
-  void RegisterTest(TestInfo&);
-
-  int RunAllTests();
-
- private:
-  static constexpr int kDefaultIterations = 10;
-
-  EventHandler* event_handler_;
-
-  // Pointer to the list of tests
-  TestInfo* tests_;
-
-  TestRunInfo run_info_;
-
-  static Framework framework_;
-};
-
-class TestInfo {
- public:
-  TestInfo(const char* test_name, void (*function_body)(State&))
-      : run_(function_body), test_name_(test_name) {
-    // Once a TestInfo object is created by the macro, this adds itself to the
-    // list of registered tests
-    Framework::Get().RegisterTest(*this);
-  }
-
-  // Returns the next registered test
-  TestInfo* next() const { return next_; }
-
-  void SetNext(TestInfo* next) { next_ = next; }
-
-  void Run(State& state) const { run_(state); }
-
-  const char* test_name() const { return test_name_; }
-
- private:
-  // Function pointer to the code that will be measured
-  void (*run_)(State&);
-
-  // Intrusively linked list, this acts as a pointer to the next test
-  TestInfo* next_ = nullptr;
-
-  const char* test_name_;
-};
-
-}  // namespace internal
-
-class State {
- public:
-  // KeepRunning() should be called in a while loop. Responsible for managing
-  // iterations and timestamps.
-  bool KeepRunning();
-
- private:
-  // Allows the framework to create state objects and unit tests for the state
-  // class
-  friend State internal::CreateState(int durations,
-                                     EventHandler& event_handler,
-                                     const char* test_name);
-
-  // Privated constructor to prevent unauthorized instances of the state class.
-  constexpr State(int iterations,
-                  EventHandler& event_handler,
-                  const char* test_name)
-      : mean_(-1),
-        test_iterations_(iterations),
-        total_duration_(0),
-        min_(std::numeric_limits<int64_t>::max()),
-        max_(std::numeric_limits<int64_t>::min()),
-        iteration_start_(),
-        current_iteration_(-1),
-        event_handler_(&event_handler),
-        test_info{.name = test_name} {
-    PW_ASSERT(test_iterations_ > 0);
-  }
-  // Set public after deciding how exactly to set user-defined iterations
-  void SetIterations(int iterations) {
-    PW_ASSERT(current_iteration_ == -1);
-    test_iterations_ = iterations;
-    PW_ASSERT(test_iterations_ > 0);
-  }
-
-  int64_t mean_;
-
-  // Stores the total number of iterations wanted
-  int test_iterations_;
-
-  // Stores the total duration of the tests.
-  int64_t total_duration_;
-
-  // Smallest value of the iterations
-  int64_t min_;
-
-  // Largest value of the iterations
-  int64_t max_;
-
-  // Time at the start of the iteration
-  internal::Timestamp iteration_start_;
-
-  // The current iteration
-  int current_iteration_;
-
-  EventHandler* event_handler_;
-
-  TestCase test_info;
-};
-
-void RunAllTests(pw::perf_test::EventHandler& handler);
+void RunAllTests(EventHandler& handler);
 
 }  // namespace pw::perf_test
diff --git a/pw_perf_test/public/pw_perf_test/state.h b/pw_perf_test/public/pw_perf_test/state.h
new file mode 100644
index 000000000..cd0e04f0c
--- /dev/null
+++ b/pw_perf_test/public/pw_perf_test/state.h
@@ -0,0 +1,87 @@
+// Copyright 2023 The Pigweed Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License"); you may not
+// use this file except in compliance with the License. You may obtain a copy of
+// the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+// License for the specific language governing permissions and limitations under
+// the License.
+#pragma once
+
+#include <cstdint>
+#include <limits>
+
+#include "pw_assert/assert.h"
+#include "pw_perf_test/event_handler.h"
+#include "pw_perf_test/internal/timer.h"
+
+namespace pw::perf_test {
+
+// Forward declaration.
+class State;
+
+namespace internal {
+
+// Allows access to the private State object constructor
+State CreateState(int durations,
+                  EventHandler& event_handler,
+                  const char* test_name);
+
+}  // namespace internal
+
+/// Records the performance of a test case over many iterations.
+class State {
+ public:
+  // KeepRunning() should be called in a while loop. Responsible for managing
+  // iterations and timestamps.
+  bool KeepRunning();
+
+ private:
+  // Allows the framework to create state objects and unit tests for the state
+  // class
+  friend State internal::CreateState(int durations,
+                                     EventHandler& event_handler,
+                                     const char* test_name);
+
+  // Privated constructor to prevent unauthorized instances of the state class.
+  constexpr State(int iterations,
+                  EventHandler& event_handler,
+                  const char* test_name)
+      : test_iterations_(iterations),
+        iteration_start_(),
+        event_handler_(&event_handler),
+        test_info{.name = test_name} {
+    PW_ASSERT(test_iterations_ > 0);
+  }
+
+  int64_t mean_ = -1;
+
+  // Stores the total number of iterations wanted
+  int test_iterations_;
+
+  // Stores the total duration of the tests.
+  int64_t total_duration_ = 0;
+
+  // Smallest value of the iterations
+  int64_t min_ = std::numeric_limits<int64_t>::max();
+
+  // Largest value of the iterations
+  int64_t max_ = std::numeric_limits<int64_t>::min();
+
+  // Time at the start of the iteration
+  internal::Timestamp iteration_start_;
+
+  // The current iteration.
+  int current_iteration_ = -1;
+
+  EventHandler* event_handler_;
+
+  TestCase test_info;
+};
+
+}  // namespace pw::perf_test
diff --git a/pw_perf_test/state.cc b/pw_perf_test/state.cc
new file mode 100644
index 000000000..7fde71adc
--- /dev/null
+++ b/pw_perf_test/state.cc
@@ -0,0 +1,66 @@
+// Copyright 2023 The Pigweed Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License"); you may not
+// use this file except in compliance with the License. You may obtain a copy of
+// the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+// License for the specific language governing permissions and limitations under
+// the License.
+
+#include "pw_perf_test/state.h"
+
+#include "pw_log/log.h"
+
+namespace pw::perf_test {
+namespace internal {
+
+State CreateState(int durations,
+                  EventHandler& event_handler,
+                  const char* test_name) {
+  return State(durations, event_handler, test_name);
+}
+}  // namespace internal
+
+bool State::KeepRunning() {
+  internal::Timestamp iteration_end = internal::GetCurrentTimestamp();
+  if (current_iteration_ == -1) {
+    ++current_iteration_;
+    event_handler_->TestCaseStart(test_info);
+    iteration_start_ = internal::GetCurrentTimestamp();
+    return true;
+  }
+  int64_t duration = internal::GetDuration(iteration_start_, iteration_end);
+  if (duration > max_) {
+    max_ = duration;
+  }
+  if (duration < min_) {
+    min_ = duration;
+  }
+  total_duration_ += duration;
+  ++current_iteration_;
+  PW_LOG_DEBUG("Iteration number: %d - Duration: %ld",
+               current_iteration_,
+               static_cast<long>(duration));
+  event_handler_->TestCaseIteration({current_iteration_, duration});
+  if (current_iteration_ == test_iterations_) {
+    PW_LOG_DEBUG("Total Duration: %ld  Total Iterations: %d",
+                 static_cast<long>(total_duration_),
+                 test_iterations_);
+    mean_ = total_duration_ / test_iterations_;
+    PW_LOG_DEBUG("Mean: %ld: ", static_cast<long>(mean_));
+    PW_LOG_DEBUG("Minimum: %ld", static_cast<long>(min_));
+    PW_LOG_DEBUG("Maxmimum: %ld", static_cast<long>(max_));
+    event_handler_->TestCaseEnd(test_info,
+                                Results{mean_, max_, min_, test_iterations_});
+    return false;
+  }
+  iteration_start_ = internal::GetCurrentTimestamp();
+  return true;
+}
+
+}  // namespace pw::perf_test
diff --git a/pw_perf_test/state_test.cc b/pw_perf_test/state_test.cc
index 647e47a3b..bd3e87330 100644
--- a/pw_perf_test/state_test.cc
+++ b/pw_perf_test/state_test.cc
@@ -12,9 +12,10 @@
 // License for the specific language governing permissions and limitations under
 // the License.
 
+#include "pw_perf_test/state.h"
+
 #include "gtest/gtest.h"
 #include "pw_perf_test/event_handler.h"
-#include "pw_perf_test/perf_test.h"
 
 namespace pw::perf_test {
 namespace {
diff --git a/pw_perf_test/test_info.cc b/pw_perf_test/test_info.cc
new file mode 100644
index 000000000..91a390ef0
--- /dev/null
+++ b/pw_perf_test/test_info.cc
@@ -0,0 +1,28 @@
+// Copyright 2023 The Pigweed Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License"); you may not
+// use this file except in compliance with the License. You may obtain a copy of
+// the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+// License for the specific language governing permissions and limitations under
+// the License.
+
+#include "pw_perf_test/internal/test_info.h"
+
+#include "pw_perf_test/internal/framework.h"
+
+namespace pw::perf_test::internal {
+
+TestInfo::TestInfo(const char* test_name, void (*function_body)(State&))
+    : run_(function_body), test_name_(test_name) {
+  // Once a TestInfo object is created by the macro, this adds itself to the
+  // list of registered tests
+  Framework::Get().RegisterTest(*this);
+}
+
+}  // namespace pw::perf_test::internal