File Detect-new-BTF-api-btf_dump__new-btf_dump__new_... of Package bpftrace

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File Detect-new-BTF-api-btf_dump__new-btf_dump__new_v0_6_0.patch of Package bpftrace (Revision e2227b2c467a2d8f6e520d8fe8d4749f)

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From 3d451feeddf725d11bb52dfbc49b616724d24fd0 Mon Sep 17 00:00:00 2001
From: Jiri Olsa <jolsa@kernel.org>
Date: Tue, 22 Feb 2022 16:36:44 +0100
Subject: [PATCH 1/1] Detect new BTF api btf_dump__new/btf_dump__new_v0_6_0

Some of the libbpf functions we use  got deprecated and
replaced with new versions.

btf__get_nr_types to btf__type_cnt
   btf_dump__new changed arguments

Adding detection of this and making bpftrace to compile
against latest libbpf.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
---
 CMakeLists.txt         |  8 +++++++
 cmake/FindLibBpf.cmake | 25 ++++++++++++++++++++
 src/btf.cpp            | 52 +++++++++++++++++++++++++++---------------
 3 files changed, 66 insertions(+), 19 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index ffbddf9c..7e5338db 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -274,6 +274,14 @@ if (LIBBPF_BTF_DUMP_FOUND)
   endif()
 endif(LIBBPF_BTF_DUMP_FOUND)
 
+if (HAVE_LIBBPF_BTF_TYPE_CNT)
+	set(BPFTRACE_FLAGS "${BPFTRACE_FLAGS}" HAVE_LIBBPF_BTF_TYPE_CNT)
+endif(HAVE_LIBBPF_BTF_TYPE_CNT)
+
+if (HAVE_LIBBPF_BTF_DUMP_NEW_V0_6_0)
+	set(BPFTRACE_FLAGS "${BPFTRACE_FLAGS}" HAVE_LIBBPF_BTF_DUMP_NEW_V0_6_0)
+endif(HAVE_LIBBPF_BTF_DUMP_NEW_V0_6_0)
+
 if (LIBDW_FOUND)
   set(BPFTRACE_FLAGS "${BPFTRACE_FLAGS}" HAVE_LIBDW)
 endif ()
diff --git a/cmake/FindLibBpf.cmake b/cmake/FindLibBpf.cmake
index 86eb8050..b088415f 100644
--- a/cmake/FindLibBpf.cmake
+++ b/cmake/FindLibBpf.cmake
@@ -55,4 +55,29 @@ if (LIBBPF_FOUND)
   check_symbol_exists(bpf_link_create "${LIBBPF_INCLUDE_DIRS}/bpf/bpf.h" HAVE_LIBBPF_LINK_CREATE)
   SET(CMAKE_REQUIRED_DEFINITIONS)
   SET(CMAKE_REQUIRED_LIBRARIES)
+
+  INCLUDE(CheckCXXSourceCompiles)
+  SET(CMAKE_REQUIRED_INCLUDES ${LIBBPF_INCLUDE_DIRS})
+  SET(CMAKE_REQUIRED_LIBRARIES ${LIBBPF_LIBRARIES} elf z)
+  CHECK_CXX_SOURCE_COMPILES("
+#include <bpf/btf.h>
+
+int main(void) {
+  btf__type_cnt(NULL);
+  return 0;
+}
+" HAVE_LIBBPF_BTF_TYPE_CNT)
+
+  CHECK_CXX_SOURCE_COMPILES("
+#include <bpf/btf.h>
+
+int main(void) {
+  const struct btf_dump_opts *opts = (const struct btf_dump_opts*) 1;
+
+  btf_dump__new(NULL, NULL, NULL, opts);
+  return 0;
+}
+" HAVE_LIBBPF_BTF_DUMP_NEW_V0_6_0)
+  SET(CMAKE_REQUIRED_INCLUDES)
+  SET(CMAKE_REQUIRED_LIBRARIES)
 endif()
diff --git a/src/btf.cpp b/src/btf.cpp
index 7d83cf68..c08ef17b 100644
--- a/src/btf.cpp
+++ b/src/btf.cpp
@@ -28,6 +28,15 @@
 
 namespace bpftrace {
 
+static __u32 type_cnt(const struct btf *btf)
+{
+#ifdef HAVE_LIBBPF_BTF_TYPE_CNT
+  return btf__type_cnt(btf);
+#else
+  return btf__get_nr_types(btf);
+#endif
+}
+
 static unsigned char *get_data(const char *file, ssize_t *sizep)
 {
   struct stat st;
@@ -185,6 +194,21 @@ static void dump_printf(void *ctx, const char *fmt, va_list args)
   free(str);
 }
 
+static struct btf_dump *dump_new(const struct btf *btf,
+                                 btf_dump_printf_fn_t dump_printf,
+                                 void *ctx)
+{
+#ifdef HAVE_LIBBPF_BTF_DUMP_NEW_V0_6_0
+  return btf_dump__new(btf, dump_printf, ctx, nullptr);
+#else
+  struct btf_dump_opts opts = {
+    .ctx = ctx,
+  };
+
+  return btf_dump__new(btf, nullptr, &opts, dump_printf);
+#endif
+}
+
 static const char *btf_str(const struct btf *btf, __u32 off)
 {
   if (!off)
@@ -220,12 +244,11 @@ std::string BTF::c_def(const std::unordered_set<std::string> &set) const
     return std::string("");
 
   std::string ret = std::string("");
-  struct btf_dump_opts opts = { .ctx = &ret, };
   struct btf_dump *dump;
   char err_buf[256];
   int err;
 
-  dump = btf_dump__new(btf, nullptr, &opts, dump_printf);
+  dump = dump_new(btf, dump_printf, &ret);
   err = libbpf_get_error(dump);
   if (err)
   {
@@ -235,7 +258,7 @@ std::string BTF::c_def(const std::unordered_set<std::string> &set) const
   }
 
   std::unordered_set<std::string> myset(set);
-  __s32 id, max = (__s32) btf__get_nr_types(btf);
+  __s32 id, max = (__s32)type_cnt(btf);
 
   for (id = 1; id <= max && myset.size(); id++)
   {
@@ -415,7 +438,7 @@ int BTF::resolve_args(const std::string &func,
   if (!has_data())
     throw std::runtime_error("BTF data not available");
 
-  __s32 id, max = (__s32)btf__get_nr_types(btf);
+  __s32 id, max = (__s32)type_cnt(btf);
   std::string name = func;
 
   for (id = 1; id <= max; id++)
@@ -486,17 +509,14 @@ int BTF::resolve_args(const std::string &func,
 
 std::unique_ptr<std::istream> BTF::get_all_funcs() const
 {
-  __s32 id, max = (__s32)btf__get_nr_types(btf);
+  __s32 id, max = (__s32)type_cnt(btf);
   std::string type = std::string("");
-  struct btf_dump_opts opts = {
-    .ctx = &type,
-  };
   struct btf_dump *dump;
   std::string funcs;
   char err_buf[256];
   int err;
 
-  dump = btf_dump__new(btf, nullptr, &opts, dump_printf);
+  dump = dump_new(btf, dump_printf, &type);
   err = libbpf_get_error(dump);
   if (err)
   {
@@ -545,16 +565,13 @@ std::map<std::string, std::vector<std::string>> BTF::get_params(
     const std::set<std::string> &funcs) const
 {
 #ifdef HAVE_LIBBPF_BTF_DUMP_EMIT_TYPE_DECL
-  __s32 id, max = (__s32)btf__get_nr_types(btf);
+  __s32 id, max = (__s32)type_cnt(btf);
   std::string type = std::string("");
-  struct btf_dump_opts opts = {
-    .ctx = &type,
-  };
   struct btf_dump *dump;
   char err_buf[256];
   int err;
 
-  dump = btf_dump__new(btf, nullptr, &opts, dump_printf);
+  dump = dump_new(btf, dump_printf, &type);
   err = libbpf_get_error(dump);
   if (err)
   {
@@ -639,16 +656,13 @@ std::map<std::string, std::vector<std::string>> BTF::get_params(
 std::set<std::string> BTF::get_all_structs() const
 {
   std::set<std::string> struct_set;
-  __s32 id, max = (__s32)btf__get_nr_types(btf);
+  __s32 id, max = (__s32)type_cnt(btf);
   std::string types = std::string("");
-  struct btf_dump_opts opts = {
-    .ctx = &types,
-  };
   struct btf_dump *dump;
   char err_buf[256];
   int err;
 
-  dump = btf_dump__new(btf, nullptr, &opts, dump_printf);
+  dump = dump_new(btf, dump_printf, &types);
   err = libbpf_get_error(dump);
   if (err)
   {
-- 
2.35.3

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File Detect-new-BTF-api-btf_dump__new-btf_dump__new_v0_6_0.patch of Package bpftrace (Revision e2227b2c467a2d8f6e520d8fe8d4749f)

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