diff options
Diffstat (limited to 'tools/lib/bpf/libbpf.c')
| -rw-r--r-- | tools/lib/bpf/libbpf.c | 67 |
1 files changed, 41 insertions, 26 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 794dd5064ae8..2b57d7ea7836 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -20,6 +20,7 @@ #include <inttypes.h> #include <string.h> #include <unistd.h> +#include <endian.h> #include <fcntl.h> #include <errno.h> #include <asm/unistd.h> @@ -181,7 +182,6 @@ struct bpf_program { bpf_program_clear_priv_t clear_priv; enum bpf_attach_type expected_attach_type; - int btf_fd; void *func_info; __u32 func_info_rec_size; __u32 func_info_cnt; @@ -312,7 +312,6 @@ void bpf_program__unload(struct bpf_program *prog) prog->instances.nr = -1; zfree(&prog->instances.fds); - zclose(prog->btf_fd); zfree(&prog->func_info); zfree(&prog->line_info); } @@ -391,7 +390,6 @@ bpf_program__init(void *data, size_t size, char *section_name, int idx, prog->instances.fds = NULL; prog->instances.nr = -1; prog->type = BPF_PROG_TYPE_UNSPEC; - prog->btf_fd = -1; return 0; errout: @@ -612,10 +610,10 @@ errout: static int bpf_object__check_endianness(struct bpf_object *obj) { -#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ +#if __BYTE_ORDER == __LITTLE_ENDIAN if (obj->efile.ehdr.e_ident[EI_DATA] == ELFDATA2LSB) return 0; -#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__ +#elif __BYTE_ORDER == __BIG_ENDIAN if (obj->efile.ehdr.e_ident[EI_DATA] == ELFDATA2MSB) return 0; #else @@ -1377,8 +1375,13 @@ static void bpf_object__sanitize_btf(struct bpf_object *obj) if (!has_datasec && kind == BTF_KIND_VAR) { /* replace VAR with INT */ t->info = BTF_INFO_ENC(BTF_KIND_INT, 0, 0); - t->size = sizeof(int); - *(int *)(t+1) = BTF_INT_ENC(0, 0, 32); + /* + * using size = 1 is the safest choice, 4 will be too + * big and cause kernel BTF validation failure if + * original variable took less than 4 bytes + */ + t->size = 1; + *(int *)(t+1) = BTF_INT_ENC(0, 0, 8); } else if (!has_datasec && kind == BTF_KIND_DATASEC) { /* replace DATASEC with STRUCT */ struct btf_var_secinfo *v = (void *)(t + 1); @@ -1500,6 +1503,12 @@ static int bpf_object__sanitize_and_load_btf(struct bpf_object *obj) BTF_ELF_SEC, err); btf__free(obj->btf); obj->btf = NULL; + /* btf_ext can't exist without btf, so free it as well */ + if (obj->btf_ext) { + btf_ext__free(obj->btf_ext); + obj->btf_ext = NULL; + } + if (bpf_object__is_btf_mandatory(obj)) return err; } @@ -2276,9 +2285,6 @@ bpf_program_reloc_btf_ext(struct bpf_program *prog, struct bpf_object *obj, prog->line_info_rec_size = btf_ext__line_info_rec_size(obj->btf_ext); } - if (!insn_offset) - prog->btf_fd = btf__fd(obj->btf); - return 0; } @@ -2451,7 +2457,7 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt, char *cp, errmsg[STRERR_BUFSIZE]; int log_buf_size = BPF_LOG_BUF_SIZE; char *log_buf; - int ret; + int btf_fd, ret; if (!insns || !insns_cnt) return -EINVAL; @@ -2466,7 +2472,12 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt, load_attr.license = license; load_attr.kern_version = kern_version; load_attr.prog_ifindex = prog->prog_ifindex; - load_attr.prog_btf_fd = prog->btf_fd >= 0 ? prog->btf_fd : 0; + /* if .BTF.ext was loaded, kernel supports associated BTF for prog */ + if (prog->obj->btf_ext) + btf_fd = bpf_object__btf_fd(prog->obj); + else + btf_fd = -1; + load_attr.prog_btf_fd = btf_fd >= 0 ? btf_fd : 0; load_attr.func_info = prog->func_info; load_attr.func_info_rec_size = prog->func_info_rec_size; load_attr.func_info_cnt = prog->func_info_cnt; @@ -4507,13 +4518,13 @@ struct perf_buffer *perf_buffer__new(int map_fd, size_t page_cnt, const struct perf_buffer_opts *opts) { struct perf_buffer_params p = {}; - struct perf_event_attr attr = { - .config = PERF_COUNT_SW_BPF_OUTPUT, - .type = PERF_TYPE_SOFTWARE, - .sample_type = PERF_SAMPLE_RAW, - .sample_period = 1, - .wakeup_events = 1, - }; + struct perf_event_attr attr = { 0, }; + + attr.config = PERF_COUNT_SW_BPF_OUTPUT, + attr.type = PERF_TYPE_SOFTWARE; + attr.sample_type = PERF_SAMPLE_RAW; + attr.sample_period = 1; + attr.wakeup_events = 1; p.attr = &attr; p.sample_cb = opts ? opts->sample_cb : NULL; @@ -4988,13 +4999,15 @@ int libbpf_num_possible_cpus(void) static const char *fcpu = "/sys/devices/system/cpu/possible"; int len = 0, n = 0, il = 0, ir = 0; unsigned int start = 0, end = 0; + int tmp_cpus = 0; static int cpus; char buf[128]; int error = 0; int fd = -1; - if (cpus > 0) - return cpus; + tmp_cpus = READ_ONCE(cpus); + if (tmp_cpus > 0) + return tmp_cpus; fd = open(fcpu, O_RDONLY); if (fd < 0) { @@ -5017,7 +5030,7 @@ int libbpf_num_possible_cpus(void) } buf[len] = '\0'; - for (ir = 0, cpus = 0; ir <= len; ir++) { + for (ir = 0, tmp_cpus = 0; ir <= len; ir++) { /* Each sub string separated by ',' has format \d+-\d+ or \d+ */ if (buf[ir] == ',' || buf[ir] == '\0') { buf[ir] = '\0'; @@ -5029,13 +5042,15 @@ int libbpf_num_possible_cpus(void) } else if (n == 1) { end = start; } - cpus += end - start + 1; + tmp_cpus += end - start + 1; il = ir + 1; } } - if (cpus <= 0) { - pr_warning("Invalid #CPUs %d from %s\n", cpus, fcpu); + if (tmp_cpus <= 0) { + pr_warning("Invalid #CPUs %d from %s\n", tmp_cpus, fcpu); return -EINVAL; } - return cpus; + + WRITE_ONCE(cpus, tmp_cpus); + return tmp_cpus; } |