chore(profiling): move echion to dd-trace-py (backport 4.0) (#15591)

## What does this PR do?

This is a backport of #15136
to 4.0. More details in the original PR.

Author: KowalskiThomas

ddtrace/internal/datadog/profiling/echion/.clang-format

@@ -0,0 +1,110 @@
+Language: Cpp
+BasedOnStyle: Google
+AccessModifierOffset: -4
+AlignAfterOpenBracket: Align
+AlignConsecutiveAssignments: false
+AlignConsecutiveDeclarations: false
+AlignEscapedNewlines: Left
+AlignOperands: true
+AlignTrailingComments: true
+AllowAllParametersOfDeclarationOnNextLine: true
+AllowShortBlocksOnASingleLine: false
+AllowShortCaseLabelsOnASingleLine: false
+AllowShortFunctionsOnASingleLine: Empty
+AllowShortIfStatementsOnASingleLine: false
+AllowShortLoopsOnASingleLine: false
+AlwaysBreakAfterDefinitionReturnType: None
+AlwaysBreakAfterReturnType: None
+AlwaysBreakBeforeMultilineStrings: false
+AlwaysBreakTemplateDeclarations: Yes
+BinPackArguments: true
+BinPackParameters: true
+BraceWrapping:
+  AfterClass: true
+  AfterControlStatement: true
+  AfterEnum: true
+  AfterFunction: true
+  AfterNamespace: true
+  AfterStruct: true
+  AfterUnion: true
+  BeforeCatch: true
+  BeforeElse: true
+  IndentBraces: false
+BreakBeforeBinaryOperators: None
+BreakBeforeBraces: Custom
+BreakBeforeInheritanceComma: false
+BreakInheritanceList: BeforeColon
+BreakBeforeTernaryOperators: true
+BreakConstructorInitializersBeforeComma: false
+BreakConstructorInitializers: BeforeColon
+BreakAfterJavaFieldAnnotations: false
+BreakStringLiterals: true
+ColumnLimit: 100
+CommentPragmas: '^ IWYU pragma:'
+CompactNamespaces: false
+ConstructorInitializerAllOnOneLineOrOnePerLine: true
+ConstructorInitializerIndentWidth: 4
+ContinuationIndentWidth: 4
+Cpp11BracedListStyle: true
+DerivePointerAlignment: false
+DisableFormat: false
+ExperimentalAutoDetectBinPacking: false
+FixNamespaceComments: true
+ForEachMacros:
+  - foreach
+  - Q_FOREACH
+  - BOOST_FOREACH
+IncludeBlocks: Preserve
+IncludeCategories:
+  - Regex: '^<.*\.h>'
+    Priority: 1
+  - Regex: '^<.*'
+    Priority: 2
+  - Regex: '.*'
+    Priority: 3
+IncludeIsMainRegex: '([-_](test|unittest))?$'
+IndentCaseLabels: true
+IndentPPDirectives: None
+IndentWidth: 4
+IndentWrappedFunctionNames: false
+JavaScriptQuotes: Leave
+JavaScriptWrapImports: true
+KeepEmptyLinesAtTheStartOfBlocks: false
+MacroBlockBegin: ''
+MacroBlockEnd: ''
+MaxEmptyLinesToKeep: 2
+NamespaceIndentation: None
+ObjCBinPackProtocolList: Never
+ObjCBlockIndentWidth: 4
+ObjCSpaceAfterProperty: false
+ObjCSpaceBeforeProtocolList: true
+PenaltyBreakAssignment: 2
+PenaltyBreakBeforeFirstCallParameter: 1
+PenaltyBreakComment: 300
+PenaltyBreakFirstLessLess: 120
+PenaltyBreakString: 1000
+PenaltyBreakTemplateDeclaration: 10
+PenaltyExcessCharacter: 1000000
+PenaltyReturnTypeOnItsOwnLine: 200
+PointerAlignment: Left
+ReflowComments: true
+SortIncludes: true
+SortUsingDeclarations: true
+SpaceAfterCStyleCast: false
+SpaceAfterTemplateKeyword: true
+SpaceBeforeAssignmentOperators: true
+SpaceBeforeCpp11BracedList: false
+SpaceBeforeCtorInitializerColon: true
+SpaceBeforeInheritanceColon: true
+SpaceBeforeParens: ControlStatements
+SpaceBeforeRangeBasedForLoopColon: true
+SpaceInEmptyParentheses: false
+SpacesBeforeTrailingComments: 2
+SpacesInAngles: false
+SpacesInContainerLiterals: false
+SpacesInCStyleCastParentheses: false
+SpacesInParentheses: false
+SpacesInSquareBrackets: false
+Standard: Cpp11
+TabWidth: 4
+UseTab: Never

ddtrace/internal/datadog/profiling/stack_v2/CMakeLists.txt

@@ -54,30 +54,9 @@ if(NOT Threads_FOUND OR NOT CMAKE_USE_PTHREADS_INIT)
     message(FATAL_ERROR "pthread compatible library not found")
 endif()
 
-# Add echion
-set(ECHION_COMMIT
-    "43432c5c0a89617b06533215a15d0d6ffbbfd02b" # https://github.com/P403n1x87/echion/commit/43432c5c0a89617b06533215a15d0d6ffbbfd02b
-    CACHE STRING "Commit hash of echion to use")
-FetchContent_Declare(
-    echion
-    GIT_REPOSITORY "https://github.com/P403n1x87/echion.git"
-    GIT_TAG ${ECHION_COMMIT})
-FetchContent_GetProperties(echion)
-
-if(NOT echion_POPULATED)
-    FetchContent_Populate(echion)
-endif()
-
 # Specify the target C-extension that we want to build
-add_library(
-    ${EXTENSION_NAME} SHARED
-    ${echion_SOURCE_DIR}/echion/frame.cc
-    ${echion_SOURCE_DIR}/echion/render.cc
-    ${echion_SOURCE_DIR}/echion/danger.cc
-    src/sampler.cpp
-    src/stack_renderer.cpp
-    src/stack_v2.cpp
-    src/thread_span_links.cpp)
+add_library(${EXTENSION_NAME} SHARED src/echion/danger.cc src/echion/frame.cc src/sampler.cpp src/stack_renderer.cpp
+                                     src/stack_v2.cpp src/thread_span_links.cpp)
 
 # Add common config
 add_ddup_config(${EXTENSION_NAME})
@@ -89,7 +68,6 @@ add_cppcheck_target(
     ${CMAKE_CURRENT_SOURCE_DIR}/include
     ${CMAKE_CURRENT_SOURCE_DIR}/include/util
     ${CMAKE_CURRENT_SOURCE_DIR}/..
-    ${echion_SOURCE_DIR}
     SRC
     ${CMAKE_CURRENT_SOURCE_DIR}/src)
 
@@ -100,8 +78,8 @@ target_compile_definitions(${EXTENSION_NAME} PRIVATE UNWIND_NATIVE_DISABLE)
 target_include_directories(
     ${EXTENSION_NAME} PRIVATE .. # include dd_wrapper from the root in order to make its paths transparent in the code
                               include)
-target_include_directories(${EXTENSION_NAME} SYSTEM PRIVATE ${echion_SOURCE_DIR} ${Python3_INCLUDE_DIRS}
-                                                            include/vendored include/util)
+target_include_directories(${EXTENSION_NAME} SYSTEM PRIVATE ${Python3_INCLUDE_DIRS} echion include/vendored
+                                                            include/util)
 
 # Echion sources need to be given the current platform
 if(APPLE)

ddtrace/internal/datadog/profiling/stack_v2/echion/echion/cache.h

@@ -0,0 +1,64 @@
+// This file is part of "echion" which is released under MIT.
+//
+// Copyright (c) 2023 Gabriele N. Tornetta <[email protected]>.
+
+#pragma once
+
+#include <functional>
+#include <list>
+#include <memory>
+#include <unordered_map>
+
+#include <echion/errors.h>
+
+#define CACHE_MAX_ENTRIES 2048
+
+template<typename K, typename V>
+class LRUCache
+{
+  public:
+    LRUCache(size_t capacity)
+      : capacity(capacity)
+    {
+    }
+
+    Result<std::reference_wrapper<V>> lookup(const K& k);
+
+    void store(const K& k, std::unique_ptr<V> v);
+
+  private:
+    size_t capacity;
+    std::list<std::pair<K, std::unique_ptr<V>>> items;
+    std::unordered_map<K, typename std::list<std::pair<K, std::unique_ptr<V>>>::iterator> index;
+};
+
+template<typename K, typename V>
+void
+LRUCache<K, V>::store(const K& k, std::unique_ptr<V> v)
+{
+    // Check if cache is full
+    if (items.size() >= capacity) {
+        index.erase(items.back().first);
+        items.pop_back();
+    }
+
+    // Insert the new item at front of the list
+    items.emplace_front(k, std::move(v));
+
+    // Insert in the map
+    index[k] = items.begin();
+}
+
+template<typename K, typename V>
+Result<std::reference_wrapper<V>>
+LRUCache<K, V>::lookup(const K& k)
+{
+    auto itr = index.find(k);
+    if (itr == index.end())
+        return ErrorKind::LookupError;
+
+    // Move to the front of the list
+    items.splice(items.begin(), items, itr->second);
+
+    return std::reference_wrapper<V>(*(itr->second->second.get()));
+}

ddtrace/internal/datadog/profiling/stack_v2/echion/echion/config.h

@@ -0,0 +1,74 @@
+// This file is part of "echion" which is released under MIT.
+//
+// Copyright (c) 2023 Gabriele N. Tornetta <[email protected]>.
+
+#pragma once
+
+#define PY_SSIZE_T_CLEAN
+#include <Python.h>
+
+// Sampling interval
+inline unsigned int interval = 1000;
+
+// CPU Time mode
+inline int cpu = 0;
+
+// For cpu time mode, Echion only unwinds threads that're running by default.
+// Set this to false to unwind all threads.
+inline bool ignore_non_running_threads = true;
+
+// Maximum number of frames to unwind
+inline unsigned int max_frames = 2048;
+
+// ----------------------------------------------------------------------------
+static PyObject*
+set_interval(PyObject* Py_UNUSED(m), PyObject* args)
+{
+    unsigned int new_interval;
+    if (!PyArg_ParseTuple(args, "I", &new_interval))
+        return NULL;
+
+    interval = new_interval;
+
+    Py_RETURN_NONE;
+}
+
+// ----------------------------------------------------------------------------
+inline void
+_set_cpu(int new_cpu)
+{
+    cpu = new_cpu;
+}
+
+// ----------------------------------------------------------------------------
+inline void
+_set_ignore_non_running_threads(bool new_ignore_non_running_threads)
+{
+    ignore_non_running_threads = new_ignore_non_running_threads;
+}
+
+// ----------------------------------------------------------------------------
+static PyObject*
+set_cpu(PyObject* Py_UNUSED(m), PyObject* args)
+{
+    int new_cpu;
+    if (!PyArg_ParseTuple(args, "p", &new_cpu))
+        return NULL;
+
+    _set_cpu(new_cpu);
+
+    Py_RETURN_NONE;
+}
+
+// ----------------------------------------------------------------------------
+static PyObject*
+set_max_frames(PyObject* Py_UNUSED(m), PyObject* args)
+{
+    unsigned int new_max_frames;
+    if (!PyArg_ParseTuple(args, "I", &new_max_frames))
+        return NULL;
+
+    max_frames = new_max_frames;
+
+    Py_RETURN_NONE;
+}