Implement CallProfiler

cpp/modmesh/toggle/CMakeLists.txt

@@ -11,6 +11,7 @@ set(MODMESH_TOGGLE_HEADERS
 
 set(MODMESH_TOGGLE_SOURCES
     ${CMAKE_CURRENT_SOURCE_DIR}/toggle.cpp
+    ${CMAKE_CURRENT_SOURCE_DIR}/RadixTree.cpp
     CACHE FILEPATH "" FORCE)
 
 set(MODMESH_TOGGLE_PYMODHEADERS

cpp/modmesh/toggle/RadixTree.cpp

@@ -0,0 +1,76 @@
+/*
+ * Copyright (c) 2023, Yung-Yu Chen <[email protected]>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright notice,
+ *   this list of conditions and the following disclaimer.
+ * - Redistributions in binary form must reproduce the above copyright notice,
+ *   this list of conditions and the following disclaimer in the documentation
+ *   and/or other materials provided with the distribution.
+ * - Neither the name of the copyright holder nor the names of its contributors
+ *   may be used to endorse or promote products derived from this software
+ *   without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <modmesh/toggle/RadixTree.hpp>
+
+namespace modmesh
+{
+
+void CallProfiler::reset()
+{
+    while (!m_radix_tree.is_root())
+    {
+        CallerProfile & profile = m_radix_tree.get_current_node()->data();
+        if (profile.is_running)
+        {
+            profile.stop_stopwatch();
+        }
+        m_radix_tree.move_current_to_parent();
+    }
+    m_radix_tree.reset();
+}
+
+// NOLINTNEXTLINE(misc-no-recursion)
+void CallProfiler::print_profiling_result(const RadixTreeNode<CallerProfile> & node, const int depth, std::ostream & outstream) const
+{
+    for (int i = 0; i < depth; ++i)
+    {
+        outstream << "  ";
+    }
+
+    auto profile = node.data();
+
+    if (depth == 0)
+    {
+        outstream << "Profiling Result" << std::endl;
+    }
+    else
+    {
+        outstream << profile.caller_name << " - Total Time: " << profile.total_time.count() / 1e6 << " ms, Call Count: " << profile.call_count << std::endl;
+    }
+
+    for (const auto & child : node.children())
+    {
+        // NOLINTNEXTLINE(misc-no-recursion)
+        print_profiling_result(*child, depth + 1, outstream);
+    }
+}
+
+} /* end namespace modmesh */
+
+// vim: set ff=unix fenc=utf8 et sw=4 ts=4 sts=4:

cpp/modmesh/toggle/RadixTree.hpp

@@ -28,13 +28,15 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include <sstream>
+#include <algorithm>
+#include <chrono>
+#include <functional>
 #include <iostream>
-#include <memory>
 #include <list>
-#include <unordered_map>
+#include <memory>
+#include <sstream>
 #include <stack>
-#include <algorithm>
+#include <unordered_map>
 
 namespace modmesh
 {
@@ -110,6 +112,13 @@ class RadixTreeNode
         return (it != m_children.end()) ? it->get() : nullptr;
     }
 
+    RadixTreeNode<T> * get_child(std::string name) const
+    {
+        auto it = std::find_if(m_children.begin(), m_children.end(), [&](const auto & child)
+                               { return child->name() == name; });
+        return (it != m_children.end()) ? it->get() : nullptr;
+    }
+
     RadixTreeNode<T> * get_prev() const { return m_prev; }
 
 private:
@@ -162,6 +171,19 @@ class RadixTree
         }
     }
 
+    void reset()
+    {
+        m_root = std::move(std::make_unique<RadixTreeNode<T>>());
+        m_current_node = m_root.get();
+        m_id_map.clear();
+        m_unique_id = 0;
+    }
+
+    bool is_root() const
+    {
+        return m_current_node == m_root.get();
+    }
+
     RadixTreeNode<T> * get_current_node() const { return m_current_node; }
     key_type get_unique_node() const { return m_unique_id; }
 
@@ -179,5 +201,146 @@ class RadixTree
     key_type m_unique_id = 0;
 }; /* end class RadixTree */
 
+// The profiling result of the caller
+struct CallerProfile
+{
+    void start_stopwatch()
+    {
+        start_time = std::chrono::high_resolution_clock::now();
+        is_running = true;
+    }
+
+    void stop_stopwatch()
+    {
+        auto end_time = std::chrono::high_resolution_clock::now();
+        auto elapsed_time = std::chrono::duration_cast<std::chrono::nanoseconds>(end_time - start_time);
+        total_time += elapsed_time;
+        call_count++;
+    }
+
+    std::chrono::high_resolution_clock::time_point start_time;
+    std::function<void()> cancel_callback;
+    std::string caller_name;
+    std::chrono::nanoseconds total_time = std::chrono::nanoseconds(0); /// use nanoseconds to have higher precision
+    int call_count = 0;
+    bool is_running = false;
+}; /* end struct CallerProfile */
+
+namespace detail
+{
+class CallProfilerTest; // for gtest
+}
+
+/// The profiler that profiles the hierarchical caller stack.
+class CallProfiler
+{
+private:
+    CallProfiler() = default;
+
+public:
+    /// A singleton.
+    static CallProfiler & instance()
+    {
+        static CallProfiler instance;
+        return instance;
+    }
+
+    CallProfiler(CallProfiler const &) = delete;
+    CallProfiler(CallProfiler &&) = delete;
+    CallProfiler & operator=(CallProfiler const &) = delete;
+    CallProfiler & operator=(CallProfiler &&) = delete;
+    ~CallProfiler() = default;
+
+    // Called when a function starts
+    void start_caller(const std::string & caller_name, std::function<void()> cancel_callback)
+    {
+        auto start_time = std::chrono::high_resolution_clock::now();
+        m_radix_tree.entry(caller_name);
+        CallerProfile & callProfile = m_radix_tree.get_current_node()->data();
+        callProfile.caller_name = caller_name;
+        callProfile.start_stopwatch();
+    }
+
+    // Called when a function ends
+    void end_caller(const std::string & caller_name)
+    {
+        CallerProfile & call_profile = m_radix_tree.get_current_node()->data();
+        call_profile.stop_stopwatch(); // Update profiling information
+        m_radix_tree.move_current_to_parent(); // Pop the caller from the call stack
+    }
+
+    /// Print the profiling information
+    void print_profiling_result(std::ostream & outstream) const
+    {
+        print_profiling_result(*(m_radix_tree.get_current_node()), 0, outstream);
+    }
+
+    /// Reset the profiler
+    void reset();
+
+private:
+    void print_profiling_result(const RadixTreeNode<CallerProfile> & node, const int depth, std::ostream & outstream) const;
+
+private:
+    RadixTree<CallerProfile> m_radix_tree; /// the data structure of the callers
+
+    friend detail::CallProfilerTest;
+}; /* end class CallProfiler */
+
+/// Utility to profile a call
+class CallProfilerProbe
+{
+public:
+    CallProfilerProbe(CallProfiler & profiler, const char * caller_name)
+        : m_profiler(profiler)
+        , m_caller_name(caller_name)
+    {
+        auto cancel_callback = [&]()
+        {
+            cancel();
+        };
+        m_profiler.start_caller(m_caller_name, cancel_callback);
+    }
+
+    CallProfilerProbe(CallProfilerProbe const &) = delete;
+    CallProfilerProbe(CallProfilerProbe &&) = delete;
+    CallProfilerProbe & operator=(CallProfilerProbe const &) = delete;
+    CallProfilerProbe & operator=(CallProfilerProbe &&) = delete;
+
+    ~CallProfilerProbe()
+    {
+        if (!m_cancel)
+        {
+            m_profiler.end_caller(m_caller_name);
+        }
+    }
+
+    void cancel()
+    {
+        m_cancel = true;
+    }
+
+private:
+    const char * m_caller_name;
+    bool m_cancel = false;
+    CallProfiler & m_profiler;
+}; /* end struct CallProfilerProbe */
+
+#ifdef CALLPROFILER
+
+#ifdef _MSC_VER
+// ref: https://learn.microsoft.com/en-us/cpp/preprocessor/predefined-macros
+#define __CROSS_PRETTY_FUNCTION__ __FUNCSIG__
+#else
+// ref: https://gcc.gnu.org/onlinedocs/gcc/Function-Names.html
+#define __CROSS_PRETTY_FUNCTION__ __PRETTY_FUNCTION__
+#endif
+#define USE_CALLPROFILER_PROFILE_THIS_FUNCTION() modmesh::CallProfilerProbe __profilerProbe##__COUNTER__(modmesh::CallProfiler::instance(), __CROSS_PRETTY_FUNCTION__)
+#define USE_CALLPROFILER_PROFILE_THIS_SCOPE(scopeName) modmesh::CallProfilerProbe __profilerProbe##__COUNTER__(modmesh::CallProfiler::instance(), scopeName)
+#else
+#define USE_CALLPROFILER_PROFILE_THIS_FUNCTION() // do nothing
+#define USE_CALLPROFILER_PROFILE_THIS_SCOPE(scopeName) // do nothing
+#endif
+
 } /* end namespace modmesh */
 // vim: set ff=unix fenc=utf8 et sw=4 ts=4 sts=4:

gtests/CMakeLists.txt

@@ -23,6 +23,8 @@ add_executable(
     test_nopython_modmesh.cpp
     test_nopython_inout.cpp
     test_nopython_radixtree.cpp
+    test_nopython_callprofiler.cpp
+    ${MODMESH_TOGGLE_SOURCES}
 )
 target_link_libraries(
     test_nopython