From c41226654550b0a8aa75e91ce0a1cdb6ce2316ee Mon Sep 17 00:00:00 2001
From: Andrii Nakryiko <andrii@kernel.org>
Date: Thu, 18 Mar 2021 12:40:32 -0700
Subject: [PATCH] bpftool: Add ability to specify custom skeleton object name
Add optional name OBJECT_NAME parameter to `gen skeleton` command to override
default object name, normally derived from input file name. This allows much
more flexibility during build time.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210318194036.3521577-9-andrii@kernel.org
---
.../bpf/bpftool/Documentation/bpftool-gen.rst | 13 +++++----
tools/bpf/bpftool/bash-completion/bpftool | 11 ++++++-
tools/bpf/bpftool/gen.c | 29 +++++++++++++++++--
3 files changed, 44 insertions(+), 9 deletions(-)
diff --git a/tools/bpf/bpftool/Documentation/bpftool-gen.rst b/tools/bpf/bpftool/Documentation/bpftool-gen.rst
index 84cf0639696f58..d4e7338e22e738 100644
--- a/tools/bpf/bpftool/Documentation/bpftool-gen.rst
+++ b/tools/bpf/bpftool/Documentation/bpftool-gen.rst
@@ -19,7 +19,7 @@ SYNOPSIS
GEN COMMANDS
=============
-| **bpftool** **gen skeleton** *FILE*
+| **bpftool** **gen skeleton** *FILE* [**name** *OBJECT_NAME*]
| **bpftool** **gen help**
DESCRIPTION
@@ -75,10 +75,13 @@ DESCRIPTION
specific maps, programs, etc.
As part of skeleton, few custom functions are generated.
- Each of them is prefixed with object name, derived from
- object file name. I.e., if BPF object file name is
- **example.o**, BPF object name will be **example**. The
- following custom functions are provided in such case:
+ Each of them is prefixed with object name. Object name can
+ either be derived from object file name, i.e., if BPF object
+ file name is **example.o**, BPF object name will be
+ **example**. Object name can be also specified explicitly
+ through **name** *OBJECT_NAME* parameter. The following
+ custom functions are provided (assuming **example** as
+ the object name):
- **example__open** and **example__open_opts**.
These functions are used to instantiate skeleton. It
diff --git a/tools/bpf/bpftool/bash-completion/bpftool b/tools/bpf/bpftool/bash-completion/bpftool
index fdffbc64c65c68..bf7b4bdbb23a3e 100644
--- a/tools/bpf/bpftool/bash-completion/bpftool
+++ b/tools/bpf/bpftool/bash-completion/bpftool
@@ -982,7 +982,16 @@ _bpftool()
gen)
case $command in
skeleton)
- _filedir
+ case $prev in
+ $command)
+ _filedir
+ return 0
+ ;;
+ *)
+ _bpftool_once_attr 'name'
+ return 0
+ ;;
+ esac
;;
*)
[[ $prev == $object ]] && \
diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c
index 4033c46d83e7dc..9bff89a66835d1 100644
--- a/tools/bpf/bpftool/gen.c
+++ b/tools/bpf/bpftool/gen.c
@@ -273,7 +273,7 @@ static int do_skeleton(int argc, char **argv)
char header_guard[MAX_OBJ_NAME_LEN + sizeof("__SKEL_H__")];
size_t i, map_cnt = 0, prog_cnt = 0, file_sz, mmap_sz;
DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts);
- char obj_name[MAX_OBJ_NAME_LEN], *obj_data;
+ char obj_name[MAX_OBJ_NAME_LEN] = "", *obj_data;
struct bpf_object *obj = NULL;
const char *file, *ident;
struct bpf_program *prog;
@@ -288,6 +288,28 @@ static int do_skeleton(int argc, char **argv)
}
file = GET_ARG();
+ while (argc) {
+ if (!REQ_ARGS(2))
+ return -1;
+
+ if (is_prefix(*argv, "name")) {
+ NEXT_ARG();
+
+ if (obj_name[0] != '\0') {
+ p_err("object name already specified");
+ return -1;
+ }
+
+ strncpy(obj_name, *argv, MAX_OBJ_NAME_LEN - 1);
+ obj_name[MAX_OBJ_NAME_LEN - 1] = '\0';
+ } else {
+ p_err("unknown arg %s", *argv);
+ return -1;
+ }
+
+ NEXT_ARG();
+ }
+
if (argc) {
p_err("extra unknown arguments");
return -1;
@@ -310,7 +332,8 @@ static int do_skeleton(int argc, char **argv)
p_err("failed to mmap() %s: %s", file, strerror(errno));
goto out;
}
- get_obj_name(obj_name, file);
+ if (obj_name[0] == '\0')
+ get_obj_name(obj_name, file);
opts.object_name = obj_name;
obj = bpf_object__open_mem(obj_data, file_sz, &opts);
if (IS_ERR(obj)) {
@@ -599,7 +622,7 @@ static int do_help(int argc, char **argv)
}
fprintf(stderr,
- "Usage: %1$s %2$s skeleton FILE\n"
+ "Usage: %1$s %2$s skeleton FILE [name OBJECT_NAME]\n"
" %1$s %2$s help\n"
"\n"
" " HELP_SPEC_OPTIONS "\n"
--
GitLab