Commit 097d8002 authored by Andrii Nakryiko's avatar Andrii Nakryiko Committed by Daniel Borkmann
Browse files

libbpf: Wire through log_true_size for bpf_btf_load() API 



Similar to what we did for bpf_prog_load() in previous patch, wire
returning of log_true_size value from kernel back to the user through
OPTS out field.

Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230406234205.323208-17-andrii@kernel.org
parent 94e55c0f

tools/lib/bpf/bpf.c

+4 −2
Original line number Diff line number Diff line
@@ -1083,9 +1083,9 @@ int bpf_raw_tracepoint_open(const char *name, int prog_fd) 
	return libbpf_err_errno(fd);

}



int bpf_btf_load(const void *btf_data, size_t btf_size, const struct bpf_btf_load_opts *opts)

int bpf_btf_load(const void *btf_data, size_t btf_size, struct bpf_btf_load_opts *opts)

{

	const size_t attr_sz = offsetofend(union bpf_attr, btf_log_level);

	const size_t attr_sz = offsetofend(union bpf_attr, btf_log_true_size);

	union bpf_attr attr;

	char *log_buf;

	size_t log_size;
@@ -1128,6 +1128,8 @@ int bpf_btf_load(const void *btf_data, size_t btf_size, const struct bpf_btf_loa 
		attr.btf_log_level = 1;

		fd = sys_bpf_fd(BPF_BTF_LOAD, &attr, attr_sz);

	}



	OPTS_SET(opts, log_true_size, attr.btf_log_true_size);

	return libbpf_err_errno(fd);

}

tools/lib/bpf/bpf.h

+9 −2
Original line number Diff line number Diff line
@@ -124,11 +124,18 @@ struct bpf_btf_load_opts { 
	char *log_buf;

	__u32 log_level;

	__u32 log_size;

	/* output: actual total log contents size (including termintaing zero).

	 * It could be both larger than original log_size (if log was

	 * truncated), or smaller (if log buffer wasn't filled completely).

	 * If kernel doesn't support this feature, log_size is left unchanged.

	 */

	__u32 log_true_size;

	size_t :0;

};

#define bpf_btf_load_opts__last_field log_size

#define bpf_btf_load_opts__last_field log_true_size



LIBBPF_API int bpf_btf_load(const void *btf_data, size_t btf_size,

			    const struct bpf_btf_load_opts *opts);

			    struct bpf_btf_load_opts *opts);



LIBBPF_API int bpf_map_update_elem(int fd, const void *key, const void *value,

				   __u64 flags);