After this patch functions attached on perf hooks is allowed to invoke
external functions. Add a testcase for this feature.

Signed-off-by: Wang Nan <wangn...@huawei.com>
Cc: Arnaldo Carvalho de Melo <a...@redhat.com>
Cc: Alexei Starovoitov <a...@fb.com>
Cc: He Kuang <heku...@huawei.com>
Cc: Jiri Olsa <jo...@kernel.org>
Cc: Zefan Li <lize...@huawei.com>
Cc: pi3or...@163.com
---
 tools/perf/tests/Build                |  2 +-
 tools/perf/tests/bpf-script-example.c |  4 ++++
 tools/perf/util/c++/clang-c.h         |  2 ++
 tools/perf/util/c++/clang-test.cpp    |  9 +++++++++
 tools/perf/util/c++/clang.cpp         | 17 ++++++++++++++++-
 5 files changed, 32 insertions(+), 2 deletions(-)

diff --git a/tools/perf/tests/Build b/tools/perf/tests/Build
index 6676c2d..d6e6e00 100644
--- a/tools/perf/tests/Build
+++ b/tools/perf/tests/Build
@@ -49,7 +49,7 @@ $(OUTPUT)tests/llvm-src-base.c: tests/bpf-script-example.c 
tests/Build
        $(call rule_mkdir)
        $(Q)echo '#include <tests/llvm.h>' > $@
        $(Q)echo 'const char test_llvm__bpf_base_prog[] =' >> $@
-       $(Q)sed -e 's/"/\\"/g' -e 's/\(.*\)/"\1\\n"/g' $< >> $@
+       $(Q)sed -e 's/\\/\\\\/g' -e 's/"/\\"/g' -e 's/\(.*\)/"\1\\n"/g' $< >> $@
        $(Q)echo ';' >> $@
 
 $(OUTPUT)tests/llvm-src-kbuild.c: tests/bpf-script-test-kbuild.c tests/Build
diff --git a/tools/perf/tests/bpf-script-example.c 
b/tools/perf/tests/bpf-script-example.c
index 265036e..ccbc19c 100644
--- a/tools/perf/tests/bpf-script-example.c
+++ b/tools/perf/tests/bpf-script-example.c
@@ -48,9 +48,13 @@ char _license[] SEC("license") = "GPL";
 int _version SEC("version") = LINUX_VERSION_CODE;
 
 #ifdef TEST_PERF_HOOK
+extern int printf(const char *fmt, ...);
+extern void test__clang_callback(int x);
 SEC("perfhook:test")
 void hook_test(void)
 {
+       printf("Hello, hook_test\n");
+       test__clang_callback(1234);
        return;
 }
 #endif
diff --git a/tools/perf/util/c++/clang-c.h b/tools/perf/util/c++/clang-c.h
index 5ebcb41..9f75e41 100644
--- a/tools/perf/util/c++/clang-c.h
+++ b/tools/perf/util/c++/clang-c.h
@@ -16,6 +16,8 @@ extern int test__clang_to_IR(void);
 extern int test__clang_to_obj(void);
 extern int test__clang_jit(void);
 
+extern void test__clang_callback(int x);
+
 extern int perf_clang__compile_bpf(const char *filename,
                                   void **p_obj_buf,
                                   size_t *p_obj_buf_sz);
diff --git a/tools/perf/util/c++/clang-test.cpp 
b/tools/perf/util/c++/clang-test.cpp
index 2b4aa8d..0bdb807 100644
--- a/tools/perf/util/c++/clang-test.cpp
+++ b/tools/perf/util/c++/clang-test.cpp
@@ -68,6 +68,13 @@ int test__clang_to_obj(void)
        return 0;
 }
 
+static int callback_flag;
+
+void test__clang_callback(int x)
+{
+       callback_flag = x;
+}
+
 int test__clang_jit(void)
 {
        perf_clang_scope _scope;
@@ -84,6 +91,8 @@ int test__clang_jit(void)
                perf_hooks__set_hook(i.first.c_str(), i.second, NULL);
 
        perf_hooks__invoke_test();
+       if (callback_flag != 1234)
+               return -1;
        return 0;
 }
 
diff --git a/tools/perf/util/c++/clang.cpp b/tools/perf/util/c++/clang.cpp
index 03012b2..325fbe4 100644
--- a/tools/perf/util/c++/clang.cpp
+++ b/tools/perf/util/c++/clang.cpp
@@ -30,6 +30,8 @@
 #include "llvm/Target/TargetOptions.h"
 #include <memory>
 #include <vector>
+#include <set>
+#include <tuple>
 
 #include "clang.h"
 #include "clang-c.h"
@@ -194,6 +196,15 @@ PerfModule::toBPFObject(void)
        return std::move(Buffer);
 }
 
+static std::map<const std::string, const void *> exported_funcs =
+{
+#define EXPORT(f) {#f, (const void *)&f}
+       EXPORT(test__clang_callback),
+       EXPORT(printf),
+       EXPORT(puts),
+#undef EXPORT
+};
+
 /*
  * Use a global memory manager so allocated code and data won't be released
  * when object destroy.
@@ -220,7 +231,11 @@ int PerfModule::doJIT(void)
 
        auto Resolver = createLambdaResolver(
                        [](const std::string &Name) {
-                               return RuntimeDyld::SymbolInfo(nullptr);
+                               auto i = exported_funcs.find(Name);
+                               if (i == exported_funcs.end())
+                                       return RuntimeDyld::SymbolInfo(nullptr);
+                               return 
RuntimeDyld::SymbolInfo((uint64_t)(i->second),
+                                                              
JITSymbolFlags::Exported);
                        },
                        [](const std::string &Name) {
                                return RuntimeDyld::SymbolInfo(nullptr);
-- 
2.10.1

Reply via email to