From d1313e01271d2d8f33d6c82f1afb77e820a3540d Mon Sep 17 00:00:00 2001 From: Sahid Orentino Ferdjaoui Date: Sun, 20 Nov 2022 11:26:32 +0000 Subject: [PATCH] bpftool: clean-up usage of libbpf_get_error() bpftool is now totally compliant with libbpf 1.0 mode and is not expected to be compiled with pre-1.0, let's clean-up the usage of libbpf_get_error(). The changes stay aligned with returned errors always negative. - In tools/bpf/bpftool/btf.c This fixes an uninitialized local variable `err` in function do_dump() because it may now be returned without having been set. - This also removes the checks on NULL pointers before calling btf__free() because that function already does the check. Signed-off-by: Sahid Orentino Ferdjaoui Link: https://lore.kernel.org/r/20221120112515.38165-5-sahid.ferdjaoui@industrialdiscipline.com Signed-off-by: Alexei Starovoitov --- tools/bpf/bpftool/btf.c | 19 ++++++++----------- tools/bpf/bpftool/btf_dumper.c | 2 +- tools/bpf/bpftool/gen.c | 10 ++++------ tools/bpf/bpftool/iter.c | 10 ++++++---- tools/bpf/bpftool/main.c | 7 +++---- tools/bpf/bpftool/map.c | 15 +++++++-------- tools/bpf/bpftool/prog.c | 10 +++++----- tools/bpf/bpftool/struct_ops.c | 11 +++++------ 8 files changed, 39 insertions(+), 45 deletions(-) diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c index b87e4a7fd689..352290ba7b29 100644 --- a/tools/bpf/bpftool/btf.c +++ b/tools/bpf/bpftool/btf.c @@ -467,9 +467,8 @@ static int dump_btf_c(const struct btf *btf, int err = 0, i; d = btf_dump__new(btf, btf_dump_printf, NULL, NULL); - err = libbpf_get_error(d); - if (err) - return err; + if (!d) + return -errno; printf("#ifndef __VMLINUX_H__\n"); printf("#define __VMLINUX_H__\n"); @@ -512,11 +511,9 @@ static struct btf *get_vmlinux_btf_from_sysfs(void) struct btf *base; base = btf__parse(sysfs_vmlinux, NULL); - if (libbpf_get_error(base)) { - p_err("failed to parse vmlinux BTF at '%s': %ld\n", - sysfs_vmlinux, libbpf_get_error(base)); - base = NULL; - } + if (!base) + p_err("failed to parse vmlinux BTF at '%s': %d\n", + sysfs_vmlinux, -errno); return base; } @@ -559,7 +556,7 @@ static int do_dump(int argc, char **argv) __u32 btf_id = -1; const char *src; int fd = -1; - int err; + int err = 0; if (!REQ_ARGS(2)) { usage(); @@ -634,8 +631,8 @@ static int do_dump(int argc, char **argv) base = get_vmlinux_btf_from_sysfs(); btf = btf__parse_split(*argv, base ?: base_btf); - err = libbpf_get_error(btf); if (!btf) { + err = -errno; p_err("failed to load BTF from %s: %s", *argv, strerror(errno)); goto done; @@ -681,8 +678,8 @@ static int do_dump(int argc, char **argv) } btf = btf__load_from_kernel_by_id_split(btf_id, base_btf); - err = libbpf_get_error(btf); if (!btf) { + err = -errno; p_err("get btf by id (%u): %s", btf_id, strerror(errno)); goto done; } diff --git a/tools/bpf/bpftool/btf_dumper.c b/tools/bpf/bpftool/btf_dumper.c index 19924b6ce796..eda71fdfe95a 100644 --- a/tools/bpf/bpftool/btf_dumper.c +++ b/tools/bpf/bpftool/btf_dumper.c @@ -75,7 +75,7 @@ static int dump_prog_id_as_func_ptr(const struct btf_dumper *d, goto print; prog_btf = btf__load_from_kernel_by_id(info.btf_id); - if (libbpf_get_error(prog_btf)) + if (!prog_btf) goto print; func_type = btf__type_by_id(prog_btf, finfo.type_id); if (!func_type || !btf_is_func(func_type)) diff --git a/tools/bpf/bpftool/gen.c b/tools/bpf/bpftool/gen.c index 01bb8d8f5568..2883660d6b67 100644 --- a/tools/bpf/bpftool/gen.c +++ b/tools/bpf/bpftool/gen.c @@ -252,9 +252,8 @@ static int codegen_datasecs(struct bpf_object *obj, const char *obj_name) int err = 0; d = btf_dump__new(btf, codegen_btf_dump_printf, NULL, NULL); - err = libbpf_get_error(d); - if (err) - return err; + if (!d) + return -errno; bpf_object__for_each_map(map, obj) { /* only generate definitions for memory-mapped internal maps */ @@ -976,13 +975,12 @@ static int do_skeleton(int argc, char **argv) /* log_level1 + log_level2 + stats, but not stable UAPI */ opts.kernel_log_level = 1 + 2 + 4; obj = bpf_object__open_mem(obj_data, file_sz, &opts); - err = libbpf_get_error(obj); - if (err) { + if (!obj) { char err_buf[256]; + err = -errno; libbpf_strerror(err, err_buf, sizeof(err_buf)); p_err("failed to open BPF object file: %s", err_buf); - obj = NULL; goto out; } diff --git a/tools/bpf/bpftool/iter.c b/tools/bpf/bpftool/iter.c index a3e6b167153d..9a1d2365a297 100644 --- a/tools/bpf/bpftool/iter.c +++ b/tools/bpf/bpftool/iter.c @@ -4,6 +4,7 @@ #ifndef _GNU_SOURCE #define _GNU_SOURCE #endif +#include #include #include #include @@ -48,8 +49,8 @@ static int do_pin(int argc, char **argv) } obj = bpf_object__open(objfile); - err = libbpf_get_error(obj); - if (err) { + if (!obj) { + err = -errno; p_err("can't open objfile %s", objfile); goto close_map_fd; } @@ -62,13 +63,14 @@ static int do_pin(int argc, char **argv) prog = bpf_object__next_program(obj, NULL); if (!prog) { + err = -errno; p_err("can't find bpf program in objfile %s", objfile); goto close_obj; } link = bpf_program__attach_iter(prog, &iter_opts); - err = libbpf_get_error(link); - if (err) { + if (!link) { + err = -errno; p_err("attach_iter failed for program %s", bpf_program__name(prog)); goto close_obj; diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c index c53c553adcac..08d0ac543c67 100644 --- a/tools/bpf/bpftool/main.c +++ b/tools/bpf/bpftool/main.c @@ -510,10 +510,9 @@ int main(int argc, char **argv) break; case 'B': base_btf = btf__parse(optarg, NULL); - if (libbpf_get_error(base_btf)) { - p_err("failed to parse base BTF at '%s': %ld\n", - optarg, libbpf_get_error(base_btf)); - base_btf = NULL; + if (!base_btf) { + p_err("failed to parse base BTF at '%s': %d\n", + optarg, -errno); return -1; } break; diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c index d884070a2314..eb362bd3d2c9 100644 --- a/tools/bpf/bpftool/map.c +++ b/tools/bpf/bpftool/map.c @@ -786,18 +786,18 @@ static int get_map_kv_btf(const struct bpf_map_info *info, struct btf **btf) if (info->btf_vmlinux_value_type_id) { if (!btf_vmlinux) { btf_vmlinux = libbpf_find_kernel_btf(); - err = libbpf_get_error(btf_vmlinux); - if (err) { + if (!btf_vmlinux) { p_err("failed to get kernel btf"); - return err; + return -errno; } } *btf = btf_vmlinux; } else if (info->btf_value_type_id) { *btf = btf__load_from_kernel_by_id(info->btf_id); - err = libbpf_get_error(*btf); - if (err) + if (!*btf) { + err = -errno; p_err("failed to get btf"); + } } else { *btf = NULL; } @@ -807,14 +807,13 @@ static int get_map_kv_btf(const struct bpf_map_info *info, struct btf **btf) static void free_map_kv_btf(struct btf *btf) { - if (!libbpf_get_error(btf) && btf != btf_vmlinux) + if (btf != btf_vmlinux) btf__free(btf); } static void free_btf_vmlinux(void) { - if (!libbpf_get_error(btf_vmlinux)) - btf__free(btf_vmlinux); + btf__free(btf_vmlinux); } static int diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index 2266958f203f..cfc9fdc1e863 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -322,7 +322,7 @@ static void show_prog_metadata(int fd, __u32 num_maps) return; btf = btf__load_from_kernel_by_id(map_info.btf_id); - if (libbpf_get_error(btf)) + if (!btf) goto out_free; t_datasec = btf__type_by_id(btf, map_info.btf_value_type_id); @@ -726,7 +726,7 @@ prog_dump(struct bpf_prog_info *info, enum dump_mode mode, if (info->btf_id) { btf = btf__load_from_kernel_by_id(info->btf_id); - if (libbpf_get_error(btf)) { + if (!btf) { p_err("failed to get btf"); return -1; } @@ -1663,7 +1663,7 @@ static int load_with_options(int argc, char **argv, bool first_prog_only) open_opts.kernel_log_level = 1 + 2 + 4; obj = bpf_object__open_file(file, &open_opts); - if (libbpf_get_error(obj)) { + if (!obj) { p_err("failed to open object file"); goto err_free_reuse_maps; } @@ -1882,7 +1882,7 @@ static int do_loader(int argc, char **argv) open_opts.kernel_log_level = 1 + 2 + 4; obj = bpf_object__open_file(file, &open_opts); - if (libbpf_get_error(obj)) { + if (!obj) { p_err("failed to open object file"); goto err_close_obj; } @@ -2199,7 +2199,7 @@ static char *profile_target_name(int tgt_fd) } btf = btf__load_from_kernel_by_id(info.btf_id); - if (libbpf_get_error(btf)) { + if (!btf) { p_err("failed to load btf for prog FD %d", tgt_fd); goto out; } diff --git a/tools/bpf/bpftool/struct_ops.c b/tools/bpf/bpftool/struct_ops.c index ae9ad85f5cda..903b80ff4e9a 100644 --- a/tools/bpf/bpftool/struct_ops.c +++ b/tools/bpf/bpftool/struct_ops.c @@ -32,7 +32,7 @@ static const struct btf *get_btf_vmlinux(void) return btf_vmlinux; btf_vmlinux = libbpf_find_kernel_btf(); - if (libbpf_get_error(btf_vmlinux)) + if (!btf_vmlinux) p_err("struct_ops requires kernel CONFIG_DEBUG_INFO_BTF=y"); return btf_vmlinux; @@ -45,7 +45,7 @@ static const char *get_kern_struct_ops_name(const struct bpf_map_info *info) const char *st_ops_name; kern_btf = get_btf_vmlinux(); - if (libbpf_get_error(kern_btf)) + if (!kern_btf) return ""; t = btf__type_by_id(kern_btf, info->btf_vmlinux_value_type_id); @@ -413,7 +413,7 @@ static int do_dump(int argc, char **argv) } kern_btf = get_btf_vmlinux(); - if (libbpf_get_error(kern_btf)) + if (!kern_btf) return -1; if (!json_output) { @@ -496,7 +496,7 @@ static int do_register(int argc, char **argv) open_opts.kernel_log_level = 1 + 2 + 4; obj = bpf_object__open_file(file, &open_opts); - if (libbpf_get_error(obj)) + if (!obj) return -1; set_max_rlimit(); @@ -590,8 +590,7 @@ int do_struct_ops(int argc, char **argv) err = cmd_select(cmds, argc, argv, do_help); - if (!libbpf_get_error(btf_vmlinux)) - btf__free(btf_vmlinux); + btf__free(btf_vmlinux); return err; }