[PATCH bpf-next v2 3/5] tools: replace btf__get_from_id() with btf__load_from_kernel_by_id()
From: Quentin Monnet <hidden>
Date: 2021-07-21 15:38:25
Also in:
bpf
Subsystem:
bpf [general] (safe dynamic programs and tools), bpf [selftests] (test runners & infrastructure), bpf [tooling] (bpftool), kernel selftest framework, performance events subsystem, the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Quentin Monnet, Shuah Khan, Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Namhyung Kim, Linus Torvalds
Replace the calls to deprecated function btf__get_from_id() with calls to btf__load_from_kernel_by_id() in tools/ (bpftool, perf, selftests). Update the surrounding code accordingly (instead of passing a pointer to the btf struct, get it as a return value from the function). Also make sure that btf__free() is called on the pointer after use. v2: - Given that btf__load_from_kernel_by_id() has changed since v1, adapt the code accordingly instead of just renaming the function. Also add a few calls to btf__free() when necessary. Signed-off-by: Quentin Monnet <redacted> Acked-by: John Fastabend <john.fastabend@gmail.com> --- tools/bpf/bpftool/btf.c | 8 ++---- tools/bpf/bpftool/btf_dumper.c | 6 ++-- tools/bpf/bpftool/map.c | 16 +++++------ tools/bpf/bpftool/prog.c | 29 ++++++++++++++------ tools/perf/util/bpf-event.c | 11 ++++---- tools/perf/util/bpf_counter.c | 12 ++++++-- tools/testing/selftests/bpf/prog_tests/btf.c | 4 ++- 7 files changed, 51 insertions(+), 35 deletions(-)
diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c
index 385d5c955cf3..9162a18e84c0 100644
--- a/tools/bpf/bpftool/btf.c
+++ b/tools/bpf/bpftool/btf.c@@ -580,16 +580,12 @@ static int do_dump(int argc, char **argv) } if (!btf) { - err = btf__get_from_id(btf_id, &btf); + btf = btf__load_from_kernel_by_id(btf_id); + err = libbpf_get_error(btf); if (err) { p_err("get btf by id (%u): %s", btf_id, strerror(err)); goto done; } - if (!btf) { - err = -ENOENT; - p_err("can't find btf with ID (%u)", btf_id); - goto done; - } } if (dump_c) {
diff --git a/tools/bpf/bpftool/btf_dumper.c b/tools/bpf/bpftool/btf_dumper.c
index 7ca54d046362..9c25286a5c73 100644
--- a/tools/bpf/bpftool/btf_dumper.c
+++ b/tools/bpf/bpftool/btf_dumper.c@@ -64,8 +64,10 @@ static int dump_prog_id_as_func_ptr(const struct btf_dumper *d, } info = &prog_info->info; - if (!info->btf_id || !info->nr_func_info || - btf__get_from_id(info->btf_id, &prog_btf)) + if (!info->btf_id || !info->nr_func_info) + goto print; + prog_btf = btf__load_from_kernel_by_id(info->btf_id); + if (libbpf_get_error(prog_btf)) goto print; finfo = u64_to_ptr(info->func_info); func_type = btf__type_by_id(prog_btf, finfo->type_id);
diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c
index 09ae0381205b..12787758ce03 100644
--- a/tools/bpf/bpftool/map.c
+++ b/tools/bpf/bpftool/map.c@@ -805,12 +805,11 @@ static struct btf *get_map_kv_btf(const struct bpf_map_info *info) } return btf_vmlinux; } else if (info->btf_value_type_id) { - int err; - - err = btf__get_from_id(info->btf_id, &btf); - if (err || !btf) { + btf = btf__load_from_kernel_by_id(info->btf_id); + if (libbpf_get_error(btf)) { p_err("failed to get btf"); - btf = err ? ERR_PTR(err) : ERR_PTR(-ESRCH); + if (!btf) + btf = ERR_PTR(-ESRCH); } }
@@ -1039,11 +1038,10 @@ static void print_key_value(struct bpf_map_info *info, void *key, void *value) { json_writer_t *btf_wtr; - struct btf *btf = NULL; - int err; + struct btf *btf; - err = btf__get_from_id(info->btf_id, &btf); - if (err) { + btf = btf__load_from_kernel_by_id(info->btf_id); + if (libbpf_get_error(btf)) { p_err("failed to get btf"); return; }
diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
index cc48726740ad..b1996b8f1d42 100644
--- a/tools/bpf/bpftool/prog.c
+++ b/tools/bpf/bpftool/prog.c@@ -249,10 +249,10 @@ static void show_prog_metadata(int fd, __u32 num_maps) struct bpf_map_info map_info; struct btf_var_secinfo *vsi; bool printed_header = false; - struct btf *btf = NULL; unsigned int i, vlen; void *value = NULL; const char *name; + struct btf *btf; int err; if (!num_maps)
@@ -263,8 +263,8 @@ static void show_prog_metadata(int fd, __u32 num_maps) if (!value) return; - err = btf__get_from_id(map_info.btf_id, &btf); - if (err || !btf) + btf = btf__load_from_kernel_by_id(map_info.btf_id); + if (libbpf_get_error(btf)) goto out_free; t_datasec = btf__type_by_id(btf, map_info.btf_value_type_id);
@@ -646,9 +646,12 @@ prog_dump(struct bpf_prog_info *info, enum dump_mode mode, member_len = info->xlated_prog_len; } - if (info->btf_id && btf__get_from_id(info->btf_id, &btf)) { - p_err("failed to get btf"); - return -1; + if (info->btf_id) { + btf = btf__load_from_kernel_by_id(info->btf_id); + if (libbpf_get_error(btf)) { + p_err("failed to get btf"); + return -1; + } } func_info = u64_to_ptr(info->func_info);
@@ -781,6 +784,8 @@ prog_dump(struct bpf_prog_info *info, enum dump_mode mode, kernel_syms_destroy(&dd); } + btf__free(btf); + return 0; }
@@ -2002,8 +2007,8 @@ static char *profile_target_name(int tgt_fd) struct bpf_prog_info_linear *info_linear; struct bpf_func_info *func_info; const struct btf_type *t; + struct btf *btf = NULL; char *name = NULL; - struct btf *btf; info_linear = bpf_program__get_prog_info_linear( tgt_fd, 1UL << BPF_PROG_INFO_FUNC_INFO);
@@ -2012,12 +2017,17 @@ static char *profile_target_name(int tgt_fd) return NULL; } - if (info_linear->info.btf_id == 0 || - btf__get_from_id(info_linear->info.btf_id, &btf)) { + if (info_linear->info.btf_id == 0) { p_err("prog FD %d doesn't have valid btf", tgt_fd); goto out; } + btf = btf__load_from_kernel_by_id(info_linear->info.btf_id); + if (libbpf_get_error(btf)) { + p_err("failed to load btf for prog FD %d", tgt_fd); + goto out; + } + func_info = u64_to_ptr(info_linear->info.func_info); t = btf__type_by_id(btf, func_info[0].type_id); if (!t) {
@@ -2027,6 +2037,7 @@ static char *profile_target_name(int tgt_fd) } name = strdup(btf__name_by_offset(btf, t->name_off)); out: + btf__free(btf); free(info_linear); return name; }
diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c
index cdecda1ddd36..996d025b8ed8 100644
--- a/tools/perf/util/bpf-event.c
+++ b/tools/perf/util/bpf-event.c@@ -223,10 +223,10 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session, free(info_linear); return -1; } - if (btf__get_from_id(info->btf_id, &btf)) { + btf = btf__load_from_kernel_by_id(info->btf_id); + if (libbpf_get_error(btf)) { pr_debug("%s: failed to get BTF of id %u, aborting\n", __func__, info->btf_id); err = -1; - btf = NULL; goto out; } perf_env__fetch_btf(env, info->btf_id, btf);
@@ -296,7 +296,7 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_session *session, out: free(info_linear); - free(btf); + btf__free(btf); return err ? -1 : 0; }
@@ -478,7 +478,8 @@ static void perf_env__add_bpf_info(struct perf_env *env, u32 id) if (btf_id == 0) goto out; - if (btf__get_from_id(btf_id, &btf)) { + btf = btf__load_from_kernel_by_id(btf_id); + if (libbpf_get_error(btf)) { pr_debug("%s: failed to get BTF of id %u, aborting\n", __func__, btf_id); goto out;
@@ -486,7 +487,7 @@ static void perf_env__add_bpf_info(struct perf_env *env, u32 id) perf_env__fetch_btf(env, btf_id, btf); out: - free(btf); + btf__free(btf); close(fd); }
diff --git a/tools/perf/util/bpf_counter.c b/tools/perf/util/bpf_counter.c
index 8150e03367bb..ba0f20853651 100644
--- a/tools/perf/util/bpf_counter.c
+++ b/tools/perf/util/bpf_counter.c@@ -64,8 +64,8 @@ static char *bpf_target_prog_name(int tgt_fd) struct bpf_prog_info_linear *info_linear; struct bpf_func_info *func_info; const struct btf_type *t; + struct btf *btf = NULL; char *name = NULL; - struct btf *btf; info_linear = bpf_program__get_prog_info_linear( tgt_fd, 1UL << BPF_PROG_INFO_FUNC_INFO);
@@ -74,12 +74,17 @@ static char *bpf_target_prog_name(int tgt_fd) return NULL; } - if (info_linear->info.btf_id == 0 || - btf__get_from_id(info_linear->info.btf_id, &btf)) { + if (info_linear->info.btf_id == 0) { pr_debug("prog FD %d doesn't have valid btf\n", tgt_fd); goto out; } + btf = btf__load_from_kernel_by_id(info_linear->info.btf_id); + if (libbpf_get_error(btf)) { + pr_debug("failed to load btf for prog FD %d\n", tgt_fd); + goto out; + } + func_info = u64_to_ptr(info_linear->info.func_info); t = btf__type_by_id(btf, func_info[0].type_id); if (!t) {
@@ -89,6 +94,7 @@ static char *bpf_target_prog_name(int tgt_fd) } name = strdup(btf__name_by_offset(btf, t->name_off)); out: + btf__free(btf); free(info_linear); return name; }
diff --git a/tools/testing/selftests/bpf/prog_tests/btf.c b/tools/testing/selftests/bpf/prog_tests/btf.c
index 857e3f26086f..649f87382c8d 100644
--- a/tools/testing/selftests/bpf/prog_tests/btf.c
+++ b/tools/testing/selftests/bpf/prog_tests/btf.c@@ -4350,7 +4350,8 @@ static void do_test_file(unsigned int test_num) goto done; } - err = btf__get_from_id(info.btf_id, &btf); + btf = btf__load_from_kernel_by_id(info.btf_id); + err = libbpf_get_error(btf); if (CHECK(err, "cannot get btf from kernel, err: %d", err)) goto done;
@@ -4386,6 +4387,7 @@ static void do_test_file(unsigned int test_num) fprintf(stderr, "OK"); done: + btf__free(btf); free(func_info); bpf_object__close(obj); }
--
2.30.2