From: Andrii Nakryiko <andrii@kernel.org>
Date: Mon, 13 Sep 2021 18:47:32 -0700
Subject: libbpf: Simplify BPF program auto-attach code
Patch-mainline: v5.16-rc1
Git-commit: 5532dfd42e4846e84d346a6dfe01e477e35baa65
References: jsc#PED-1377
Remove the need to explicitly pass bpf_sec_def for auto-attachable BPF
programs, as it is already recorded at bpf_object__open() time for all
recognized type of BPF programs. This further reduces number of explicit
calls to find_sec_def(), simplifying further refactorings.
No functional changes are done by this patch.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20210914014733.2768-4-andrii@kernel.org
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
---
tools/lib/bpf/libbpf.c | 61 +++++++++++++++++--------------------------------
1 file changed, 22 insertions(+), 39 deletions(-)
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -218,8 +218,7 @@ struct reloc_desc {
struct bpf_sec_def;
-typedef struct bpf_link *(*attach_fn_t)(const struct bpf_sec_def *sec,
- struct bpf_program *prog);
+typedef struct bpf_link *(*attach_fn_t)(struct bpf_program *prog);
struct bpf_sec_def {
const char *sec;
@@ -7921,18 +7920,12 @@ void bpf_program__set_expected_attach_ty
__VA_ARGS__ \
}
-static struct bpf_link *attach_kprobe(const struct bpf_sec_def *sec,
- struct bpf_program *prog);
-static struct bpf_link *attach_tp(const struct bpf_sec_def *sec,
- struct bpf_program *prog);
-static struct bpf_link *attach_raw_tp(const struct bpf_sec_def *sec,
- struct bpf_program *prog);
-static struct bpf_link *attach_trace(const struct bpf_sec_def *sec,
- struct bpf_program *prog);
-static struct bpf_link *attach_lsm(const struct bpf_sec_def *sec,
- struct bpf_program *prog);
-static struct bpf_link *attach_iter(const struct bpf_sec_def *sec,
- struct bpf_program *prog);
+static struct bpf_link *attach_kprobe(struct bpf_program *prog);
+static struct bpf_link *attach_tp(struct bpf_program *prog);
+static struct bpf_link *attach_raw_tp(struct bpf_program *prog);
+static struct bpf_link *attach_trace(struct bpf_program *prog);
+static struct bpf_link *attach_lsm(struct bpf_program *prog);
+static struct bpf_link *attach_iter(struct bpf_program *prog);
static const struct bpf_sec_def section_defs[] = {
BPF_PROG_SEC("socket", BPF_PROG_TYPE_SOCKET_FILTER),
@@ -9392,8 +9385,7 @@ struct bpf_link *bpf_program__attach_kpr
return bpf_program__attach_kprobe_opts(prog, func_name, &opts);
}
-static struct bpf_link *attach_kprobe(const struct bpf_sec_def *sec,
- struct bpf_program *prog)
+static struct bpf_link *attach_kprobe(struct bpf_program *prog)
{
DECLARE_LIBBPF_OPTS(bpf_kprobe_opts, opts);
unsigned long offset = 0;
@@ -9402,8 +9394,8 @@ static struct bpf_link *attach_kprobe(co
char *func;
int n, err;
- func_name = prog->sec_name + sec->len;
- opts.retprobe = strcmp(sec->sec, "kretprobe/") == 0;
+ func_name = prog->sec_name + prog->sec_def->len;
+ opts.retprobe = strcmp(prog->sec_def->sec, "kretprobe/") == 0;
n = sscanf(func_name, "%m[a-zA-Z0-9_.]+%li", &func, &offset);
if (n < 1) {
@@ -9566,8 +9558,7 @@ struct bpf_link *bpf_program__attach_tra
return bpf_program__attach_tracepoint_opts(prog, tp_category, tp_name, NULL);
}
-static struct bpf_link *attach_tp(const struct bpf_sec_def *sec,
- struct bpf_program *prog)
+static struct bpf_link *attach_tp(struct bpf_program *prog)
{
char *sec_name, *tp_cat, *tp_name;
struct bpf_link *link;
@@ -9577,7 +9568,7 @@ static struct bpf_link *attach_tp(const
return libbpf_err_ptr(-ENOMEM);
/* extract "tp/<category>/<name>" */
- tp_cat = sec_name + sec->len;
+ tp_cat = sec_name + prog->sec_def->len;
tp_name = strchr(tp_cat, '/');
if (!tp_name) {
free(sec_name);
@@ -9621,10 +9612,9 @@ struct bpf_link *bpf_program__attach_raw
return link;
}
-static struct bpf_link *attach_raw_tp(const struct bpf_sec_def *sec,
- struct bpf_program *prog)
+static struct bpf_link *attach_raw_tp(struct bpf_program *prog)
{
- const char *tp_name = prog->sec_name + sec->len;
+ const char *tp_name = prog->sec_name + prog->sec_def->len;
return bpf_program__attach_raw_tracepoint(prog, tp_name);
}
@@ -9669,14 +9659,12 @@ struct bpf_link *bpf_program__attach_lsm
return bpf_program__attach_btf_id(prog);
}
-static struct bpf_link *attach_trace(const struct bpf_sec_def *sec,
- struct bpf_program *prog)
+static struct bpf_link *attach_trace(struct bpf_program *prog)
{
return bpf_program__attach_trace(prog);
}
-static struct bpf_link *attach_lsm(const struct bpf_sec_def *sec,
- struct bpf_program *prog)
+static struct bpf_link *attach_lsm(struct bpf_program *prog)
{
return bpf_program__attach_lsm(prog);
}
@@ -9807,21 +9795,17 @@ bpf_program__attach_iter(struct bpf_prog
return link;
}
-static struct bpf_link *attach_iter(const struct bpf_sec_def *sec,
- struct bpf_program *prog)
+static struct bpf_link *attach_iter(struct bpf_program *prog)
{
return bpf_program__attach_iter(prog, NULL);
}
struct bpf_link *bpf_program__attach(struct bpf_program *prog)
{
- const struct bpf_sec_def *sec_def;
-
- sec_def = find_sec_def(prog->sec_name);
- if (!sec_def || !sec_def->attach_fn)
+ if (!prog->sec_def || !prog->sec_def->attach_fn)
return libbpf_err_ptr(-ESRCH);
- return sec_def->attach_fn(sec_def, prog);
+ return prog->sec_def->attach_fn(prog);
}
static int bpf_link__detach_struct_ops(struct bpf_link *link)
@@ -10900,16 +10884,15 @@ int bpf_object__attach_skeleton(struct b
for (i = 0; i < s->prog_cnt; i++) {
struct bpf_program *prog = *s->progs[i].prog;
struct bpf_link **link = s->progs[i].link;
- const struct bpf_sec_def *sec_def;
if (!prog->load)
continue;
- sec_def = find_sec_def(prog->sec_name);
- if (!sec_def || !sec_def->attach_fn)
+ /* auto-attaching not supported for this program */
+ if (!prog->sec_def || !prog->sec_def->attach_fn)
continue;
- *link = sec_def->attach_fn(sec_def, prog);
+ *link = prog->sec_def->attach_fn(prog);
err = libbpf_get_error(*link);
if (err) {
pr_warn("failed to auto-attach program '%s': %d\n",