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author | Alexei Starovoitov <ast@kernel.org> | 2020-12-03 10:17:27 -0800 |
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committer | Alexei Starovoitov <ast@kernel.org> | 2020-12-03 10:17:27 -0800 |
commit | 0d1e02695979bdf5fb08425cd823d6e906e09378 (patch) | |
tree | 9203cdc0ece7dedcbd35572e2f089410c5af882c /tools | |
parent | 97306be45fbe7a02461c3c2a57e666cf662b1aaf (diff) | |
parent | fa4528379a51ff8d5271e1bcfa0d5ef71657869f (diff) | |
download | linux-0d1e02695979bdf5fb08425cd823d6e906e09378.tar.bz2 |
Merge branch 'bpftool: improve split BTF support'
Andrii Nakryiko says:
====================
Few follow up improvements to bpftool for split BTF support:
- emit "name <anon>" for non-named BTFs in `bpftool btf show` command;
- when dumping /sys/kernel/btf/<module> use /sys/kernel/btf/vmlinux as the
base BTF, unless base BTF is explicitly specified with -B flag.
This patch set also adds btf__base_btf() getter to access base BTF of the
struct btf.
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'tools')
-rw-r--r-- | tools/bpf/bpftool/btf.c | 27 | ||||
-rw-r--r-- | tools/lib/bpf/btf.c | 5 | ||||
-rw-r--r-- | tools/lib/bpf/btf.h | 1 | ||||
-rw-r--r-- | tools/lib/bpf/libbpf.map | 1 |
4 files changed, 30 insertions, 4 deletions
diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c index ed5e97157241..94cd3bad5430 100644 --- a/tools/bpf/bpftool/btf.c +++ b/tools/bpf/bpftool/btf.c @@ -357,11 +357,13 @@ static int dump_btf_raw(const struct btf *btf, dump_btf_type(btf, root_type_ids[i], t); } } else { + const struct btf *base; int cnt = btf__get_nr_types(btf); int start_id = 1; - if (base_btf) - start_id = btf__get_nr_types(base_btf) + 1; + base = btf__base_btf(btf); + if (base) + start_id = btf__get_nr_types(base) + 1; for (i = start_id; i <= cnt; i++) { t = btf__type_by_id(btf, i); @@ -428,7 +430,7 @@ done: static int do_dump(int argc, char **argv) { - struct btf *btf = NULL; + struct btf *btf = NULL, *base = NULL; __u32 root_type_ids[2]; int root_type_cnt = 0; bool dump_c = false; @@ -502,7 +504,21 @@ static int do_dump(int argc, char **argv) } NEXT_ARG(); } else if (is_prefix(src, "file")) { - btf = btf__parse_split(*argv, base_btf); + const char sysfs_prefix[] = "/sys/kernel/btf/"; + const char sysfs_vmlinux[] = "/sys/kernel/btf/vmlinux"; + + if (!base_btf && + strncmp(*argv, sysfs_prefix, sizeof(sysfs_prefix) - 1) == 0 && + strcmp(*argv, sysfs_vmlinux) != 0) { + 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; + } + } + + btf = btf__parse_split(*argv, base ?: base_btf); if (IS_ERR(btf)) { err = -PTR_ERR(btf); btf = NULL; @@ -567,6 +583,7 @@ static int do_dump(int argc, char **argv) done: close(fd); btf__free(btf); + btf__free(base); return err; } @@ -750,6 +767,8 @@ show_btf_plain(struct bpf_btf_info *info, int fd, printf("name [%s] ", name); else if (name && name[0]) printf("name %s ", name); + else + printf("name <anon> "); printf("size %uB", info->btf_size); n = 0; diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c index 8ff46cd30ca1..1935e83d309c 100644 --- a/tools/lib/bpf/btf.c +++ b/tools/lib/bpf/btf.c @@ -432,6 +432,11 @@ __u32 btf__get_nr_types(const struct btf *btf) return btf->start_id + btf->nr_types - 1; } +const struct btf *btf__base_btf(const struct btf *btf) +{ + return btf->base_btf; +} + /* internal helper returning non-const pointer to a type */ static struct btf_type *btf_type_by_id(struct btf *btf, __u32 type_id) { diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h index 1093f6fe6800..1237bcd1dd17 100644 --- a/tools/lib/bpf/btf.h +++ b/tools/lib/bpf/btf.h @@ -51,6 +51,7 @@ LIBBPF_API __s32 btf__find_by_name(const struct btf *btf, LIBBPF_API __s32 btf__find_by_name_kind(const struct btf *btf, const char *type_name, __u32 kind); LIBBPF_API __u32 btf__get_nr_types(const struct btf *btf); +LIBBPF_API const struct btf *btf__base_btf(const struct btf *btf); LIBBPF_API const struct btf_type *btf__type_by_id(const struct btf *btf, __u32 id); LIBBPF_API size_t btf__pointer_size(const struct btf *btf); diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index 29ff4807b909..ed55498c4122 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -340,6 +340,7 @@ LIBBPF_0.2.0 { LIBBPF_0.3.0 { global: + btf__base_btf; btf__parse_elf_split; btf__parse_raw_split; btf__parse_split; |