cmake: Add systemtap-sdt optional package support

CMakeLists.txt

@@ -133,6 +133,11 @@ if(WITH_ZMQ)
   endif()
 endif()
 
+option(WITH_USDT "Enable tracepoints for Userspace, Statically Defined Tracing." OFF)
+if(WITH_USDT)
+  find_package(USDT MODULE REQUIRED)
+endif()
+
 set(configure_warnings)
 
 include(CheckPIESupported)
@@ -309,6 +314,7 @@ message("  port mapping:")
 message("   - using NAT-PMP .................... ${WITH_NATPMP}")
 message("   - using UPnP ....................... ${WITH_MINIUPNPC}")
 message("  ZeroMQ .............................. ${WITH_ZMQ}")
+message("  USDT tracing ........................ ${WITH_USDT}")
 message("Tests:")
 message("  test_bitcoin ........................ ${BUILD_TESTS}")
 message("")

cmake/bitcoin-config.h.in

@@ -38,6 +38,10 @@
 /* Define this symbol to build code that uses SSE4.1 intrinsics */
 #cmakedefine ENABLE_SSE41 1
 
+/* Define to 1 to enable tracepoints for Userspace, Statically Defined Tracing
+   */
+#cmakedefine ENABLE_TRACING 1
+
 /* Define to 1 to enable wallet functions. */
 #cmakedefine ENABLE_WALLET 1
 

cmake/module/FindUSDT.cmake

@@ -0,0 +1,64 @@
+# Copyright (c) 2024-present The Bitcoin Core developers
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or https://opensource.org/license/mit/.
+
+#[=======================================================================[
+FindUSDT
+--------
+
+Finds the Userspace, Statically Defined Tracing header(s).
+
+Imported Targets
+^^^^^^^^^^^^^^^^
+
+This module provides imported target ``USDT::headers``, if
+USDT has been found.
+
+Result Variables
+^^^^^^^^^^^^^^^^
+
+This module defines the following variables:
+
+``USDT_FOUND``
+  "True" if USDT found.
+
+#]=======================================================================]
+
+find_path(USDT_INCLUDE_DIR
+  NAMES sys/sdt.h
+)
+mark_as_advanced(USDT_INCLUDE_DIR)
+
+if(USDT_INCLUDE_DIR)
+  include(CMakePushCheckState)
+  cmake_push_check_state(RESET)
+
+  include(CheckCXXSourceCompiles)
+  set(CMAKE_REQUIRED_INCLUDES ${USDT_INCLUDE_DIR})
+  check_cxx_source_compiles("
+    #include <sys/sdt.h>
+
+    int main()
+    {
+      DTRACE_PROBE(context, event);
+      int a, b, c, d, e, f, g;
+      DTRACE_PROBE7(context, event, a, b, c, d, e, f, g);
+    }
+    " HAVE_USDT_H
+  )
+
+  cmake_pop_check_state()
+endif()
+
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(USDT
+  REQUIRED_VARS USDT_INCLUDE_DIR HAVE_USDT_H
+)
+
+if(USDT_FOUND AND NOT TARGET USDT::headers)
+  add_library(USDT::headers INTERFACE IMPORTED)
+  set_target_properties(USDT::headers PROPERTIES
+    INTERFACE_INCLUDE_DIRECTORIES "${USDT_INCLUDE_DIR}"
+  )
+  set(ENABLE_TRACING TRUE)
+endif()

src/CMakeLists.txt

@@ -141,6 +141,7 @@ target_link_libraries(bitcoin_common
     univalue
     secp256k1
     Boost::headers
+    $<TARGET_NAME_IF_EXISTS:USDT::headers>
     $<$<PLATFORM_ID:Windows>:ws2_32>
 )
 
@@ -274,6 +275,7 @@ target_link_libraries(bitcoin_node
     $<TARGET_NAME_IF_EXISTS:NATPMP::NATPMP>
     $<TARGET_NAME_IF_EXISTS:MiniUPnPc::MiniUPnPc>
     $<TARGET_NAME_IF_EXISTS:bitcoin_zmq>
+    $<TARGET_NAME_IF_EXISTS:USDT::headers>
 )
 
 

src/wallet/CMakeLists.txt

@@ -39,6 +39,7 @@ target_link_libraries(bitcoin_wallet
     bitcoin_common
     univalue
     Boost::headers
+    $<TARGET_NAME_IF_EXISTS:USDT::headers>
 )
 
 if(NOT USE_SQLITE AND NOT USE_BDB)