perf clang: Update test case to use real BPF script

Allow C++ code to use util.h and tests/llvm.h. Let 'perf test' compile a
real BPF script.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Joe Stringer <joe@ovn.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/20161126070354.141764-14-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

2 files changed, 40 insertions, 3 deletions

diff --git a/tools/perf/util/c++/clang-test.cpp b/tools/perf/util/c++/clang-test.cpp
index 0f484fb..d84e760 100644
--- a/tools/perf/util/c++/clang-test.cpp
+++ b/tools/perf/util/c++/clang-test.cpp
@@ -3,6 +3,10 @@
 #include "llvm/IR/Function.h"
 #include "llvm/IR/LLVMContext.h"
 
+#include <util-cxx.h>
+#include <tests/llvm.h>
+#include <string>
+
 class perf_clang_scope {
 public:
 	explicit perf_clang_scope() {perf_clang__init();}
@@ -14,17 +18,24 @@ extern "C" {
 int test__clang_to_IR(void)
 {
 	perf_clang_scope _scope;
+	unsigned int kernel_version;
+
+	if (fetch_kernel_version(&kernel_version, NULL, 0))
+		return -1;
+
+	std::string cflag_kver("-DLINUX_VERSION_CODE=" +
+				std::to_string(kernel_version));
 
 	std::unique_ptr<llvm::Module> M =
-		perf::getModuleFromSource({"-DRESULT=1"},
+		perf::getModuleFromSource({cflag_kver.c_str()},
 					  "perf-test.c",
-					  "int myfunc(void) {return RESULT;}");
+					  test_llvm__bpf_base_prog);
 
 	if (!M)
 		return -1;
 
 	for (llvm::Function& F : *M)
-		if (F.getName() == "myfunc")
+		if (F.getName() == "bpf_func__SyS_epoll_wait")
 			return 0;
 	return -1;
 }
diff --git a/tools/perf/util/util-cxx.h b/tools/perf/util/util-cxx.h
new file mode 100644
index 0000000..0e0e019
--- /dev/null
+++ b/tools/perf/util/util-cxx.h
@@ -0,0 +1,26 @@
+/*
+ * Support C++ source use utilities defined in util.h
+ */
+
+#ifndef PERF_UTIL_UTIL_CXX_H
+#define PERF_UTIL_UTIL_CXX_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ * Now 'new' is the only C++ keyword found in util.h:
+ * in tools/include/linux/rbtree.h
+ *
+ * Other keywords, like class and delete, should be
+ * redefined if necessary.
+ */
+#define new _new
+#include "util.h"
+#undef new
+
+#ifdef __cplusplus
+}
+#endif
+#endif