chore(profiling): replace stack_v2 with stack (#15613)

## Description

Mostly mechanical change of replacing `stack_v2` with `stack`, as we no
longer have `v1` implementation in the codebase.

Except for 

https://github.com/DataDog/dd-trace-py/blob/3d46d4af5637deb52b7c3ea7710dd0ff7419ee32/ddtrace/internal/settings/profiling.py#L389-L392

## Testing

<!-- Describe your testing strategy or note what tests are included -->

## Risks

<!-- Note any risks associated with this change, or "None" if no risks
-->

## Additional Notes

<!-- Any other information that would be helpful for reviewers -->

Author: taegyunkim

.github/workflows/profiling-native.yml

@@ -47,13 +47,13 @@ jobs:
 
       - name: Run tests with sanitizers
         run: |
-          # DEV: We currently have tests in dd_wrapper and stack_v2, setting
-          # stack_v2 here will also run tests in dd_wrapper. Revisit this when
+          # DEV: We currently have tests in dd_wrapper and stack, setting
+          # stack here will also run tests in dd_wrapper. Revisit this when
           # that changes.
           if [ "${{matrix.memcpy-mode}}" == "fast" ]; then
             export ECHION_USE_FAST_COPY_MEMORY=1
           else
             export ECHION_USE_FAST_COPY_MEMORY=0
           fi
 
-          ./ddtrace/internal/datadog/profiling/build_standalone.sh --${{matrix.sanitizer}} RelWithDebInfo stack_v2_test
+          ./ddtrace/internal/datadog/profiling/build_standalone.sh --${{matrix.sanitizer}} RelWithDebInfo stack_test

ddtrace/internal/datadog/profiling/build_standalone.sh

@@ -76,7 +76,7 @@ CLANGTIDY_CMD=${highest_clangxx/clang++/clang-tidy}
 # Targets to target dirs
 declare -A target_dirs
 target_dirs["ddup"]="ddup"
-target_dirs["stack_v2"]="stack_v2"
+target_dirs["stack"]="stack"
 target_dirs["dd_wrapper"]="dd_wrapper"
 
 # Compiler options
@@ -224,8 +224,8 @@ print_help() {
   echo ""
   echo "Targets:"
   echo "  all_test (default)"
-  echo "  stack_v2 (also builds dd_wrapper)"
-  echo "  stack_v2_test (also builds dd_wrapper_test)"
+  echo "  stack (also builds dd_wrapper)"
+  echo "  stack_test (also builds dd_wrapper_test)"
   echo "  ddup (also builds dd_wrapper)"
   echo "  ddup_test (also builds dd_wrapper_test)"
 }
@@ -350,11 +350,11 @@ add_target() {
 
   case "${target}" in
     all|--)
-      targets+=("stack_v2")
+      targets+=("stack")
       targets+=("ddup")
       ;;
-    stack_v2)
-      targets+=("stack_v2")
+    stack)
+      targets+=("stack")
       ;;
     ddup)
       targets+=("ddup")

ddtrace/internal/datadog/profiling/cmake/AnalysisFunc.cmake

@@ -87,7 +87,7 @@ function(add_ddup_config target)
         target_compile_options(${target} PRIVATE -fanalyzer)
     endif()
 
-    # The main targets, ddup, crashtracker, stack_v2, and dd_wrapper are built as dynamic libraries, so PIC is required.
+    # The main targets, ddup, crashtracker, stack, and dd_wrapper are built as dynamic libraries, so PIC is required.
     # And setting this is also fine for tests as they're loading those dynamic libraries.
     set_target_properties(${target} PROPERTIES POSITION_INDEPENDENT_CODE ON)
 

ddtrace/internal/datadog/profiling/docs/Design.md

@@ -8,9 +8,9 @@ if(NOT DEFINED BUILD_TESTING)
 endif()
 
 # The exact name of this extension determines aspects of the installation and build paths, which need to be kept in sync
-# with setup.py. Accordingly, take the name passed in by the caller, defaulting to "stack_v2" if needed.
+# with setup.py. Accordingly, take the name passed in by the caller, defaulting to "stack" if needed.
 set(EXTENSION_NAME
-    "_stack_v2"
+    "_stack"
     CACHE STRING "Name of the extension")
 project(${EXTENSION_NAME})
 message(STATUS "Building extension: ${EXTENSION_NAME}")
@@ -55,8 +55,8 @@ if(NOT Threads_FOUND OR NOT CMAKE_USE_PTHREADS_INIT)
 endif()
 
 # Specify the target C-extension that we want to build
-add_library(${EXTENSION_NAME} SHARED src/echion/danger.cc src/echion/frame.cc src/sampler.cpp src/stack_renderer.cpp
-                                     src/stack_v2.cpp src/thread_span_links.cpp)
+add_library(${EXTENSION_NAME} SHARED src/echion/danger.cc src/echion/frame.cc src/sampler.cpp src/stack.cpp
+                                     src/stack_renderer.cpp src/thread_span_links.cpp)
 
 # Add common config
 add_ddup_config(${EXTENSION_NAME})

…atadog/profiling/stack_v2/CMakeLists.txt …l/datadog/profiling/stack/CMakeLists.txtddtrace/internal/datadog/profiling/stack_v2/CMakeLists.txt renamed to ddtrace/internal/datadog/profiling/stack/CMakeLists.txt ddtrace/internal/datadog/profiling/stack_v2/CMakeLists.txt renamed to ddtrace/internal/datadog/profiling/stack/CMakeLists.txt

@@ -10,7 +10,7 @@
     from ddtrace._trace import context
     from ddtrace._trace import span as ddspan
 
-    from ._stack_v2 import *  # noqa: F403, F401
+    from ._stack import *  # noqa: F403, F401
 
     is_available = True
 
@@ -19,7 +19,7 @@ def link_span(span: typing.Optional[typing.Union[context.Context, ddspan.Span]])
             span_id = span.span_id
             local_root_span_id = span._local_root.span_id
             local_root_span_type = span._local_root.span_type
-            _stack_v2.link_span(span_id, local_root_span_id, local_root_span_type)  # type: ignore # noqa: F405
+            _stack.link_span(span_id, local_root_span_id, local_root_span_type)  # type: ignore # noqa: F405
 
 except Exception as e:
     failure_msg = str(e)