cmake: always link to packaged libbpf if CMAKE_USE_LIBBPF_PACKAGE is …

…set (iovisor#3210)

Some of the executables still link to the local static versions
even if the user requested CMAKE_USE_LIBBPF_PACKAGE. Fix this by
using bcc-shared-no-libbpf more widely if the variable is set.

Skip the git submodule and the extraction commands if the user
set CMAKE_USE_LIBBPF_PACKAGE

CMakeLists.txt

@@ -14,7 +14,7 @@ endif()
 enable_testing()
 
 # populate submodules (libbpf)
-if(NOT EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/src/cc/libbpf/src)
+if(NOT CMAKE_USE_LIBBPF_PACKAGE AND NOT EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/src/cc/libbpf/src)
  execute_process(COMMAND git submodule update --init --recursive
  WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR})
 endif()

examples/cpp/CMakeLists.txt

@@ -11,53 +11,20 @@ set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fPIC")
 
 option(INSTALL_CPP_EXAMPLES "Install C++ examples. Those binaries are statically linked and can take plenty of disk space" OFF)
 
-add_executable(HelloWorld HelloWorld.cc)
-target_link_libraries(HelloWorld bcc-static)
-
-add_executable(CPUDistribution CPUDistribution.cc)
-target_link_libraries(CPUDistribution bcc-static)
-
-add_executable(RecordMySQLQuery RecordMySQLQuery.cc)
-target_link_libraries(RecordMySQLQuery bcc-static)
-
-add_executable(TCPSendStack TCPSendStack.cc)
-target_link_libraries(TCPSendStack bcc-static)
-
-add_executable(RandomRead RandomRead.cc)
-target_link_libraries(RandomRead bcc-static)
-
-add_executable(LLCStat LLCStat.cc)
-target_link_libraries(LLCStat bcc-static)
-
-add_executable(FollyRequestContextSwitch FollyRequestContextSwitch.cc)
-target_link_libraries(FollyRequestContextSwitch bcc-static)
-
-add_executable(UseExternalMap UseExternalMap.cc)
-target_link_libraries(UseExternalMap bcc-static)
-
-add_executable(CGroupTest CGroupTest.cc)
-target_link_libraries(CGroupTest bcc-static)
-
-add_executable(TaskIterator TaskIterator.cc)
-target_link_libraries(TaskIterator bcc-static)
-
-add_executable(SkLocalStorageIterator SkLocalStorageIterator.cc)
-target_link_libraries(SkLocalStorageIterator bcc-static)
-
-add_executable(KFuncExample KFuncExample.cc)
-target_link_libraries(KFuncExample bcc-static)
-
-if(INSTALL_CPP_EXAMPLES)
- install (TARGETS HelloWorld DESTINATION share/bcc/examples/cpp)
- install (TARGETS CPUDistribution DESTINATION share/bcc/examples/cpp)
- install (TARGETS RecordMySQLQuery DESTINATION share/bcc/examples/cpp)
- install (TARGETS TCPSendStack DESTINATION share/bcc/examples/cpp)
- install (TARGETS RandomRead DESTINATION share/bcc/examples/cpp)
- install (TARGETS LLCStat DESTINATION share/bcc/examples/cpp)
- install (TARGETS FollyRequestContextSwitch DESTINATION share/bcc/examples/cpp)
- install (TARGETS UseExternalMap DESTINATION share/bcc/examples/cpp)
- install (TARGETS CGroupTest DESTINATION share/bcc/examples/cpp)
- install (TARGETS KFuncExample DESTINATION share/bcc/examples/cpp)
-endif(INSTALL_CPP_EXAMPLES)
+file(GLOB EXAMPLES *.cc)
+foreach(EXAMPLE ${EXAMPLES})
+ get_filename_component(NAME ${EXAMPLE} NAME_WE)
+ add_executable(${NAME} ${EXAMPLE})
+
+ if(NOT CMAKE_USE_LIBBPF_PACKAGE)
+ target_link_libraries(${NAME} bcc-static)
+ else()
+ target_link_libraries(${NAME} bcc-shared-no-libbpf)
+ endif()
+
+ if(INSTALL_CPP_EXAMPLES)
+ install (TARGETS ${NAME} DESTINATION share/bcc/examples/cpp)
+ endif(INSTALL_CPP_EXAMPLES)
+endforeach()
 
 add_subdirectory(pyperf)

examples/cpp/pyperf/CMakeLists.txt

@@ -7,6 +7,11 @@ include_directories(${CMAKE_SOURCE_DIR}/src/cc/libbpf/include/uapi)
 
 add_executable(PyPerf PyPerf.cc PyPerfUtil.cc PyPerfBPFProgram.cc PyPerfLoggingHelper.cc PyPerfDefaultPrinter.cc Py36Offsets.cc)
 target_link_libraries(PyPerf bcc-static)
+if(NOT CMAKE_USE_LIBBPF_PACKAGE)
+ target_link_libraries(PyPerf bcc-static)
+else()
+ target_link_libraries(PyPerf bcc-shared-no-libbpf)
+endif()
 
 if(INSTALL_CPP_EXAMPLES)
  install (TARGETS PyPerf DESTINATION share/bcc/examples/cpp)

introspection/CMakeLists.txt

@@ -8,7 +8,13 @@ include_directories(${CMAKE_SOURCE_DIR}/src/cc/libbpf/include/uapi)
 option(INSTALL_INTROSPECTION "Install BPF introspection tools" ON)
 option(BPS_LINK_RT "Pass -lrt to linker when linking bps tool" ON)
 
-set(bps_libs_to_link bpf-static elf z)
+# Note that the order matters! bpf-static first, the rest later
+if(CMAKE_USE_LIBBPF_PACKAGE AND LIBBPF_FOUND)
+set(bps_libs_to_link bpf-shared ${LIBBPF_LIBRARIES})
+else()
+set(bps_libs_to_link bpf-static)
+endif()
+list(APPEND bps_libs_to_link elf z)
 if(BPS_LINK_RT)
 list(APPEND bps_libs_to_link rt)
 endif()

src/cc/CMakeLists.txt

@@ -10,8 +10,12 @@ include_directories(${CMAKE_CURRENT_SOURCE_DIR}/frontends/clang)
 include_directories(${LLVM_INCLUDE_DIRS})
 include_directories(${LIBELF_INCLUDE_DIRS})
 # todo: if check for kernel version
-include_directories(${CMAKE_CURRENT_SOURCE_DIR}/libbpf/include)
-include_directories(${CMAKE_CURRENT_SOURCE_DIR}/libbpf/include/uapi)
+if (CMAKE_USE_LIBBPF_PACKAGE AND LIBBPF_FOUND)
+ include_directories(${LIBBPF_INCLUDE_DIRS})
+else()
+ include_directories(${CMAKE_CURRENT_SOURCE_DIR}/libbpf/include)
+ include_directories(${CMAKE_CURRENT_SOURCE_DIR}/libbpf/include/uapi)
+endif()
 
 # add_definitions has a problem parsing "-D_GLIBCXX_USE_CXX11_ABI=0", this is safer
 separate_arguments(LLVM_DEFINITIONS)
@@ -41,21 +45,26 @@ if(LIBBPF_INCLUDE_DIR)
  add_definitions(-DHAVE_EXTERNAL_LIBBPF)
 endif()
 
-if(LIBBPF_FOUND)
- set(extract_dir ${CMAKE_CURRENT_BINARY_DIR}/libbpf_a_extract)
- execute_process(COMMAND sh -c "mkdir -p ${extract_dir} && cd ${extract_dir} && ${CMAKE_AR} x ${LIBBPF_STATIC_LIBRARIES}")
- file(GLOB libbpf_sources "${extract_dir}/*.o")
-else()
- file(GLOB libbpf_sources "libbpf/src/*.c")
-endif()
+if(NOT CMAKE_USE_LIBBPF_PACKAGE)
+ if(LIBBPF_FOUND)
+ set(extract_dir ${CMAKE_CURRENT_BINARY_DIR}/libbpf_a_extract)
+ execute_process(COMMAND sh -c "mkdir -p ${extract_dir} && cd ${extract_dir} && ${CMAKE_AR} x ${LIBBPF_STATIC_LIBRARIES}")
+ file(GLOB libbpf_sources "${extract_dir}/*.o")
+ else()
+ file(GLOB libbpf_sources "libbpf/src/*.c")
+ endif()
 
-set(libbpf_uapi libbpf/include/uapi/linux/)
+ set(libbpf_uapi libbpf/include/uapi/linux/)
+endif()
 
 add_library(bpf-static STATIC libbpf.c perf_reader.c ${libbpf_sources})
 set_target_properties(bpf-static PROPERTIES OUTPUT_NAME bcc_bpf)
 add_library(bpf-shared SHARED libbpf.c perf_reader.c ${libbpf_sources})
 set_target_properties(bpf-shared PROPERTIES VERSION ${REVISION_LAST} SOVERSION 0)
 set_target_properties(bpf-shared PROPERTIES OUTPUT_NAME bcc_bpf)
+if(CMAKE_USE_LIBBPF_PACKAGE AND LIBBPF_FOUND)
+ target_link_libraries(bpf-shared ${LIBBPF_LIBRARIES})
+endif()
 
 set(bcc_common_sources bcc_common.cc bpf_module.cc bcc_btf.cc exported_files.cc)
 if (${LLVM_PACKAGE_VERSION} VERSION_EQUAL 6 OR ${LLVM_PACKAGE_VERSION} VERSION_GREATER 6)

tests/cc/CMakeLists.txt

@@ -7,7 +7,11 @@ include_directories(${CMAKE_SOURCE_DIR}/src/cc/libbpf/include/uapi)
 include_directories(${CMAKE_SOURCE_DIR}/tests/python/include)
 
 add_executable(test_static test_static.c)
-target_link_libraries(test_static bcc-static)
+if(NOT CMAKE_USE_LIBBPF_PACKAGE)
+ target_link_libraries(test_static bcc-static)
+else()
+ target_link_libraries(test_static bcc-shared-no-libbpf)
+endif()
 
 add_test(NAME c_test_static COMMAND ${TEST_WRAPPER} c_test_static sudo ${CMAKE_CURRENT_BINARY_DIR}/test_static)
 
@@ -35,17 +39,19 @@ set(TEST_LIBBCC_SOURCES
  utils.cc
  test_parse_tracepoint.cc)
 
-add_executable(test_libbcc ${TEST_LIBBCC_SOURCES})
-
 file(COPY dummy_proc_map.txt DESTINATION ${CMAKE_CURRENT_BINARY_DIR})
 add_library(usdt_test_lib SHARED usdt_test_lib.cc)
 
-add_dependencies(test_libbcc bcc-shared)
-target_link_libraries(test_libbcc ${PROJECT_BINARY_DIR}/src/cc/libbcc.so dl usdt_test_lib)
-set_target_properties(test_libbcc PROPERTIES INSTALL_RPATH ${PROJECT_BINARY_DIR}/src/cc)
-target_compile_definitions(test_libbcc PRIVATE -DLIBBCC_NAME=\"libbcc.so\")
+if(NOT CMAKE_USE_LIBBPF_PACKAGE)
+ add_executable(test_libbcc ${TEST_LIBBCC_SOURCES})
+ add_dependencies(test_libbcc bcc-shared)
 
-add_test(NAME test_libbcc COMMAND ${TEST_WRAPPER} c_test_all sudo ${CMAKE_CURRENT_BINARY_DIR}/test_libbcc)
+ target_link_libraries(test_libbcc ${PROJECT_BINARY_DIR}/src/cc/libbcc.so dl usdt_test_lib)
+ set_target_properties(test_libbcc PROPERTIES INSTALL_RPATH ${PROJECT_BINARY_DIR}/src/cc)
+ target_compile_definitions(test_libbcc PRIVATE -DLIBBCC_NAME=\"libbcc.so\")
+
+ add_test(NAME test_libbcc COMMAND ${TEST_WRAPPER} c_test_all sudo ${CMAKE_CURRENT_BINARY_DIR}/test_libbcc)
+endif()
 
 if(LIBBPF_FOUND)
  add_executable(test_libbcc_no_libbpf ${TEST_LIBBCC_SOURCES})