wasm-sdk: fix setting rodata and bss section variables

README.md

@@ -26,7 +26,7 @@ The wasm-bpf runtime require two parts: `the host side`(Outside the Wasm runtime
   - see [src](src) and [include](include) directories, which would be a sample runtime built on the top of [libbpf](https://github.com/libbpf/libbpf) and [WAMR](https://github.com/bytecodealliance/wasm-micro-runtime).
   - You can easily build your own Wasm-eBPF runtime in `any` languages, `any` eBPF libraries and `any` Wasm runtimes with the same System interface.
 - wasm side: toolchains and libraries
-  - a [`libbpf-wasm`](wasm-include/libbpf-wasm.h) header only library to provide libbpf APIs for Wasm guest `C/C++` code.
+  - a [`libbpf-wasm`](wasm-sdk/libbpf-wasm.h) header only library to provide libbpf APIs for Wasm guest `C/C++` code.
   - a [`bpftool`](https://github.com/eunomia-bpf/bpftool/tree/wasm-bpftool) tool to generate the Wasm-eBPF `skeleton` headers, and `C struct definitions` for passing data between the host and Wasm guest without serialization.
   - More languages support(`Rust`, `Go`, etc) is on the way.
 

README_zh.md

@@ -17,7 +17,7 @@
 - host 侧: 见 [src](src) 以及 [include](include) 文件夹。 主机侧是一个构建在 [libbpf](https://github.com/libbpf/libbpf) 和 [WAMR](https://github.com/bytecodealliance/wasm-micro-runtime) 之上的运行时。
   - 使用同一套工具链，任何人用任何 wasm 运行时或者任何 ebpf 用户态库，以及任何语言，都可以在两三百行三四百行内轻松实现一套 wasm+ebpf 运行时平台，运行几乎所有的 ebpf 应用场景。
 - wasm 侧:
-  - 一个用于给 Wasm 客户侧 `C/C++` 代码提供 libbpf API的头文件库([`libbpf-wasm`](wasm-include/libbpf-wasm.h))。
+  - 一个用于给 Wasm 客户侧 `C/C++` 代码提供 libbpf API的头文件库([`libbpf-wasm`](wasm-sdk/libbpf-wasm.h))。
   - 一个用来生成 Wasm-eBPF `skeleton` 头文件以及生成用于在主机侧和 Wasm 客户侧传递数据的 C 结构体定义的 [`bpftool`](https://github.com/eunomia-bpf/bpftool/tree/wasm-bpftool)。
   - 更多编程语言支持(比如 `Rust`、 `Go` 等)还在开发中。
 

examples/bootstrap/README.md

@@ -135,7 +135,7 @@ This would invoke the following steps:
   >
   > We have create a specical POC tool outside of `bpftool` for generate C structs serialization-free bindings between eBPF/host side and Wasm, you can find it in [c-struct-bindgen](https://github.com/eunomia-bpf/c-struct-bindgen). More details about how to deal with the struct layout issue can be found in the README of the c-struct-bindgen tool.
 
-  The libbpf API for wasm program is provided as an header only library, you can find it in `libbpf-wasm.h` (wasm-include/libbpf-wasm.h). The wasm program can use the libbpf API and syscall to operate the BPF object, for example:
+  The libbpf API for wasm program is provided as an header only library, you can find it in [`libbpf-wasm.h`](../../wasm-sdk/libbpf-wasm.h). The wasm program can use the libbpf API and syscall to operate the BPF object, for example:
 
     ```c
     /* Load and verify BPF application */

examples/bootstrap/README_zh.md

@@ -120,7 +120,7 @@ make
   >
   >我们创建了一个特殊的 POC 工具，它不属于 `bpftool`，可以生成 eBPF/主机端和 Wasm 之间的不需要序列化的 C 结构体绑定，您可以在 [c-struct-bindgen](https://github.com/eunomia-bpf/c-struct-bindgen) 中找到它。关于如何处理结构体布局问题的更多详细信息，可以在 c-struct-bindgen 工具的 README 中找到。
 
-libbpf API 为 wasm 程序提供了一个仅包含头文件的库，您可以在 libbpf-wasm.h（wasm-include/libbpf-wasm.h）中找到它。wasm 程序可以使用 libbpf API 和 syscall 操作 BPF 对象，例如：
+libbpf API 为 wasm 程序提供了一个仅包含头文件的库，您可以在 [libbpf-wasm](../../wasm-sdk/libbpf-wasm.h) 中找到它。wasm 程序可以使用 libbpf API 和 syscall 操作 BPF 对象，例如：
 
 ```c
 /* Load and verify BPF application */

examples/bootstrap/bootstrap.c

@@ -63,6 +63,8 @@ main(int argc, char **argv)
     struct bpf_buffer *rb = NULL;
     struct bootstrap_bpf *skel;
     int err;
+
+	// parse the args manually for demo purpose
     if (argc > 3 || strcmp(argv[1], "-h") == 0 || strcmp(argv[1], "--help") == 0) {
         print_usage();
         return 0;

examples/runqlat/runqlat.c

@@ -28,7 +28,7 @@ struct env {
 	char *cgroupspath;
 	bool cg;
 } env = {
-	.interval = 99999999,
+	.interval = 1,
 	.times = 99999999,
 };
 
@@ -45,7 +45,6 @@ const char argp_program_doc[] =
 "EXAMPLES:\n"
 "    runqlat         # summarize run queue latency as a histogram\n"
 "    runqlat 1 10    # print 1 second summaries, 10 times\n"
-"    runqlat -mT 1   # 1s summaries, milliseconds, and timestamps\n"
 "    runqlat -P      # show each PID separately\n"
 "    runqlat -p 185  # trace PID 185 only\n"
 "    runqlat -c CG   # Trace process under cgroupsPath CG\n";
@@ -108,12 +107,14 @@ int main(int argc, char **argv)
 	int err;
 	int idx, cg_map_fd;
 	int cgfd = -1;
-
+
+	// parse the args manually for demo purpose
     if (argc > 3 || strcmp(argv[1], "-h") == 0 || strcmp(argv[1], "--help") == 0) {
         print_usage();
         return 0;
-    }
-    if (argc == 3) {
+    } else if (argc == 2 && strcmp(argv[1], "-P")) {
+		env.per_process = true;
+	} else if (argc == 3) {
         env.interval = atoi(argv[1]);
         env.times = atoi(argv[2]);
     } else if (argc == 2) {

wasm-sdk/libbpf-wasm.h

@@ -55,8 +55,10 @@ struct bpf_prog_skeleton {
 struct bpf_object_skeleton {
     size_t sz; /* size of this struct, for forward/backward compatibility */
     const char *name;
-    const void *data;
+    void *data;
     size_t data_sz;
+    size_t rodata_offset; /* offset of rodata section */
+	size_t bss_offset; /* offset of bss section */
 
     bpf_object_skel obj;
 
@@ -92,6 +94,15 @@ static inline int libbpf_err_errno(int ret) {
 static int bpf_map__fd(const struct bpf_map *map) {
     return wasm_bpf_map_fd_by_name(map->obj_ptr, map->name);
 }
+
+static bool
+str_has_surfix(const char *str, const char *surfix) {
+    size_t str_len = strlen(str);
+    size_t surfix_len = strlen(surfix);
+    if (str_len < surfix_len) return false;
+    return strcmp(str + str_len - surfix_len, surfix) == 0;
+}
+
 struct bpf_object_open_opts;
 static int bpf_object__open_skeleton(struct bpf_object_skeleton *s,
                                      const struct bpf_object_open_opts *opts) {
@@ -105,6 +116,14 @@ static int bpf_object__open_skeleton(struct bpf_object_skeleton *s,
         if (!*map_skel->map) return -1;
         strncpy((*map_skel->map)->name, map_skel->name,
                 sizeof((*map_skel->map)->name));
+        if (str_has_surfix(map_skel->name, "rodata") && map_skel->mmaped) {
+            // set the address to mmaped rodata variable
+            *map_skel->mmaped = s->data + s->rodata_offset;
+        }
+        // it will not work for bss, because bss is not mmaped 
+        // if (str_has_surfix(map_skel->name, "bss") && map_skel->mmaped) {
+        //     *map_skel->mmaped = s->data + s->bss_offset;
+        // }
     }
 
     for (int i = 0; i < s->prog_cnt; i++) {