[PATCH v3 28/30] perf clang: Include helpers to BPF scripts

[Wang Nan]

Automatically include some commonly used macros and struct definitions
into BPF scripts. Script writers are no longer required to define
'SEC' and 'struct bpf_map_def' in each of their scripts.

Signed-off-by: Wang Nan <wangnan0@xxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Alexei Starovoitov <ast@xxxxxx>
Cc: He Kuang <hekuang@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Zefan Li <lizefan@xxxxxxxxxx>
Cc: pi3orama@xxxxxxx
---
 tools/perf/tests/bpf-script-example.c         |  2 +-
 tools/perf/tests/bpf-script-test-kbuild.c     |  2 ++
 tools/perf/tests/bpf-script-test-prologue.c   |  4 +++-
 tools/perf/tests/bpf-script-test-relocation.c |  3 +--
 tools/perf/util/c++/Build                     |  1 +
 tools/perf/util/c++/bpf-helper-str.c          | 15 +++++++++++++++
 tools/perf/util/c++/clang-bpf-includes.h      |  1 +
 tools/perf/util/c++/clang.cpp                 |  1 +
 8 files changed, 25 insertions(+), 4 deletions(-)
 create mode 100644 tools/perf/util/c++/bpf-helper-str.c

diff --git a/tools/perf/tests/bpf-script-example.c b/tools/perf/tests/bpf-script-example.c
index 42dc341..e60bebf 100644
--- a/tools/perf/tests/bpf-script-example.c
+++ b/tools/perf/tests/bpf-script-example.c
@@ -9,6 +9,7 @@
 #define BPF_ANY 0
 #define BPF_MAP_TYPE_ARRAY 2
 
+#ifndef BUILTIN_CLANG_DEFAULT_INCLUDE
 struct bpf_map_def {
 	unsigned int type;
 	unsigned int key_size;
@@ -18,7 +19,6 @@ struct bpf_map_def {
 
 #define SEC(NAME) __attribute__((section(NAME), used))
 
-#ifndef BUILTIN_CLANG_DEFAULT_INCLUDE
 #define BPF_FUNC_map_lookup_elem 1
 #define BPF_FUNC_map_update_elem 2
 
diff --git a/tools/perf/tests/bpf-script-test-kbuild.c b/tools/perf/tests/bpf-script-test-kbuild.c
index 3626924..f1b48a4 100644
--- a/tools/perf/tests/bpf-script-test-kbuild.c
+++ b/tools/perf/tests/bpf-script-test-kbuild.c
@@ -6,7 +6,9 @@
 # error Need LINUX_VERSION_CODE
 # error Example: for 4.2 kernel, put 'clang-opt="-DLINUX_VERSION_CODE=0x40200" into llvm section of ~/.perfconfig'
 #endif
+#ifndef BUILTIN_CLANG_DEFAULT_INCLUDE
 #define SEC(NAME) __attribute__((section(NAME), used))
+#endif
 
 #include <uapi/linux/fs.h>
 #include <uapi/asm/ptrace.h>
diff --git a/tools/perf/tests/bpf-script-test-prologue.c b/tools/perf/tests/bpf-script-test-prologue.c
index ada812b..e2176c9 100644
--- a/tools/perf/tests/bpf-script-test-prologue.c
+++ b/tools/perf/tests/bpf-script-test-prologue.c
@@ -6,7 +6,6 @@
 # error Need LINUX_VERSION_CODE
 # error Example: for 4.2 kernel, put 'clang-opt="-DLINUX_VERSION_CODE=0x40200" into llvm section of ~/.perfconfig'
 #endif
-#define SEC(NAME) __attribute__((section(NAME), used))
 
 #include <uapi/linux/fs.h>
 
@@ -14,6 +13,9 @@
 #define FMODE_WRITE		0x2
 
 #ifndef BUILTIN_CLANG_DEFAULT_INCLUDE
+
+#define SEC(NAME) __attribute__((section(NAME), used))
+
 static void (*bpf_trace_printk)(const char *fmt, int fmt_size, ...) =
 	(void *) 6;
 #endif
diff --git a/tools/perf/tests/bpf-script-test-relocation.c b/tools/perf/tests/bpf-script-test-relocation.c
index 57c96a3..bb54926 100644
--- a/tools/perf/tests/bpf-script-test-relocation.c
+++ b/tools/perf/tests/bpf-script-test-relocation.c
@@ -9,6 +9,7 @@
 #define BPF_ANY 0
 #define BPF_MAP_TYPE_ARRAY 2
 
+#ifndef BUILTIN_CLANG_DEFAULT_INCLUDE
 struct bpf_map_def {
 	unsigned int type;
 	unsigned int key_size;
@@ -17,8 +18,6 @@ struct bpf_map_def {
 };
 
 #define SEC(NAME) __attribute__((section(NAME), used))
-
-#ifndef BUILTIN_CLANG_DEFAULT_INCLUDE
 #define BPF_FUNC_map_lookup_elem 1
 #define BPF_FUNC_map_update_elem 2
 
diff --git a/tools/perf/util/c++/Build b/tools/perf/util/c++/Build
index bd71abf..faa0268 100644
--- a/tools/perf/util/c++/Build
+++ b/tools/perf/util/c++/Build
@@ -1,3 +1,4 @@
 libperf-$(CONFIG_CLANGLLVM) += clang.o
 libperf-$(CONFIG_CLANGLLVM) += clang-test.o
 libperf-$(CONFIG_CLANGLLVM) += bpf-funcs-str.o
+libperf-$(CONFIG_CLANGLLVM) += bpf-helper-str.o
diff --git a/tools/perf/util/c++/bpf-helper-str.c b/tools/perf/util/c++/bpf-helper-str.c
new file mode 100644
index 0000000..17f915c
--- /dev/null
+++ b/tools/perf/util/c++/bpf-helper-str.c
@@ -0,0 +1,15 @@
+#include "clang-bpf-includes.h"
+const char clang_builtin_bpf_helper_str[] =
+"#ifdef BUILTIN_CLANG_DEFAULT_INCLUDE\n"
+"#ifndef BPF_HELPER_DEFINED\n"
+"#define BPF_HELPER_DEFINED\n"
+"struct bpf_map_def {\n"
+"	unsigned int type;\n"
+"	unsigned int key_size;\n"
+"	unsigned int value_size;\n"
+"	unsigned int max_entries;\n"
+"};\n"
+"#define SEC(NAME) __attribute__((section(NAME), used))\n"
+"#endif\n"
+"#endif"
+;
diff --git a/tools/perf/util/c++/clang-bpf-includes.h b/tools/perf/util/c++/clang-bpf-includes.h
index 385a5bb..577b40c 100644
--- a/tools/perf/util/c++/clang-bpf-includes.h
+++ b/tools/perf/util/c++/clang-bpf-includes.h
@@ -5,6 +5,7 @@ extern "C" {
 #endif
 
 extern const char clang_builtin_bpf_funcs_str[];
+extern const char clang_builtin_bpf_helper_str[];
 
 #ifdef __cplusplus
 }
diff --git a/tools/perf/util/c++/clang.cpp b/tools/perf/util/c++/clang.cpp
index 926dae1..5c1efe8 100644
--- a/tools/perf/util/c++/clang.cpp
+++ b/tools/perf/util/c++/clang.cpp
@@ -48,6 +48,7 @@ static struct BPFHeader {
 	llvm::StringRef Content;
 } BPFHeaders[] = {
 	{"/virtual/bpf-funcs.h", clang_builtin_bpf_funcs_str},
+	{"/virtual/bpf-helper.h", clang_builtin_bpf_helper_str},
 };
 
 static std::unique_ptr<llvm::LLVMContext> LLVMCtx;
-- 
2.10.1