From:   menglong8.dong@gmail.com
To:     ast@kernel.org
Cc:     daniel@iogearbox.net, andrii@kernel.org, kafai@fb.com,
        songliubraving@fb.com, yhs@fb.com, john.fastabend@gmail.com,
        kpsingh@kernel.org, quentin@isovalent.com, cong.wang@bytedance.com,
        liujian56@huawei.com, davemarchevsky@fb.com, sdf@google.com,
        netdev@vger.kernel.org, bpf@vger.kernel.org,
        linux-kernel@vger.kernel.org, Menglong Dong <imagedong@tencent.com>
Subject: [PATCH] bpftool: add support of pin prog by name
Date:   Sun,  5 Dec 2021 12:50:41 +0800
Message-Id: <20211205045041.129716-1-imagedong@tencent.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: Menglong Dong <imagedong@tencent.com>

For now, the command 'bpftool prog loadall' use section name as the
name of the pin file. However, once there are prog with the same
section name in ELF file, this command will failed with the error
'File Exist'.

So, add the support of pin prog by function name with the 'pinbyname'
argument.

Signed-off-by: Menglong Dong <imagedong@tencent.com>
---
 tools/bpf/bpftool/prog.c | 7 +++++++
 tools/lib/bpf/libbpf.c   | 5 +++++
 tools/lib/bpf/libbpf.h   | 2 ++
 3 files changed, 14 insertions(+)

diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
index e47e8b06cc3d..74e0aaebfefc 100644
--- a/tools/bpf/bpftool/prog.c
+++ b/tools/bpf/bpftool/prog.c
@@ -1471,6 +1471,7 @@ static int load_with_options(int argc, char **argv, bool first_prog_only)
 	unsigned int old_map_fds = 0;
 	const char *pinmaps = NULL;
 	struct bpf_object *obj;
+	bool pinbyname = false;
 	struct bpf_map *map;
 	const char *pinfile;
 	unsigned int i, j;
@@ -1589,6 +1590,9 @@ static int load_with_options(int argc, char **argv, bool first_prog_only)
 				goto err_free_reuse_maps;
 
 			pinmaps = GET_ARG();
+		} else if (is_prefix(*argv, "pinbyname")) {
+			pinbyname = true;
+			NEXT_ARG();
 		} else {
 			p_err("expected no more arguments, 'type', 'map' or 'dev', got: '%s'?",
 			      *argv);
@@ -1616,6 +1620,9 @@ static int load_with_options(int argc, char **argv, bool first_prog_only)
 				goto err_close_obj;
 		}
 
+		if (pinbyname)
+			bpf_program__set_pinname(pos,
+						 (char *)bpf_program__name(pos));
 		bpf_program__set_ifindex(pos, ifindex);
 		bpf_program__set_type(pos, prog_type);
 		bpf_program__set_expected_attach_type(pos, expected_attach_type);
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index f6faa33c80fa..e8fc1d0fe16e 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -8119,6 +8119,11 @@ void bpf_program__set_ifindex(struct bpf_program *prog, __u32 ifindex)
 	prog->prog_ifindex = ifindex;
 }
 
+void bpf_program__set_pinname(struct bpf_program *prog, char *name)
+{
+	prog->pin_name = name;
+}
+
 const char *bpf_program__name(const struct bpf_program *prog)
 {
 	return prog->name;
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index 4ec69f224342..107cf736c2bb 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -216,6 +216,8 @@ LIBBPF_API int bpf_program__set_priv(struct bpf_program *prog, void *priv,
 LIBBPF_API void *bpf_program__priv(const struct bpf_program *prog);
 LIBBPF_API void bpf_program__set_ifindex(struct bpf_program *prog,
 					 __u32 ifindex);
+LIBBPF_API void bpf_program__set_pinname(struct bpf_program *prog,
+					 char *name);
 
 LIBBPF_API const char *bpf_program__name(const struct bpf_program *prog);
 LIBBPF_API const char *bpf_program__section_name(const struct bpf_program *prog);
-- 
2.30.2