linux/tools/lib/bpf/libbpf_legacy.h
Joe Burton 689624f037 libbpf: Deprecate bpf_objects_list
Add a flag to `enum libbpf_strict_mode' to disable the global
`bpf_objects_list', preventing race conditions when concurrent threads
call bpf_object__open() or bpf_object__close().

bpf_object__next() will return NULL if this option is set.

Callers may achieve the same workflow by tracking bpf_objects in
application code.

  [0] Closes: https://github.com/libbpf/libbpf/issues/293

Signed-off-by: Joe Burton <jevburton@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211026223528.413950-1-jevburton.kernel@gmail.com
2021-10-27 11:00:12 -07:00

78 lines
2.2 KiB
C

/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
/*
* Libbpf legacy APIs (either discouraged or deprecated, as mentioned in [0])
*
* [0] https://docs.google.com/document/d/1UyjTZuPFWiPFyKk1tV5an11_iaRuec6U-ZESZ54nNTY
*
* Copyright (C) 2021 Facebook
*/
#ifndef __LIBBPF_LEGACY_BPF_H
#define __LIBBPF_LEGACY_BPF_H
#include <linux/bpf.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include "libbpf_common.h"
#ifdef __cplusplus
extern "C" {
#endif
enum libbpf_strict_mode {
/* Turn on all supported strict features of libbpf to simulate libbpf
* v1.0 behavior.
* This will be the default behavior in libbpf v1.0.
*/
LIBBPF_STRICT_ALL = 0xffffffff,
/*
* Disable any libbpf 1.0 behaviors. This is the default before libbpf
* v1.0. It won't be supported anymore in v1.0, please update your
* code so that it handles LIBBPF_STRICT_ALL mode before libbpf v1.0.
*/
LIBBPF_STRICT_NONE = 0x00,
/*
* Return NULL pointers on error, not ERR_PTR(err).
* Additionally, libbpf also always sets errno to corresponding Exx
* (positive) error code.
*/
LIBBPF_STRICT_CLEAN_PTRS = 0x01,
/*
* Return actual error codes from low-level APIs directly, not just -1.
* Additionally, libbpf also always sets errno to corresponding Exx
* (positive) error code.
*/
LIBBPF_STRICT_DIRECT_ERRS = 0x02,
/*
* Enforce strict BPF program section (SEC()) names.
* E.g., while prefiously SEC("xdp_whatever") or SEC("perf_event_blah") were
* allowed, with LIBBPF_STRICT_SEC_PREFIX this will become
* unrecognized by libbpf and would have to be just SEC("xdp") and
* SEC("xdp") and SEC("perf_event").
*
* Note, in this mode the program pin path will be based on the
* function name instead of section name.
*/
LIBBPF_STRICT_SEC_NAME = 0x04,
/*
* Disable the global 'bpf_objects_list'. Maintaining this list adds
* a race condition to bpf_object__open() and bpf_object__close().
* Clients can maintain it on their own if it is valuable for them.
*/
LIBBPF_STRICT_NO_OBJECT_LIST = 0x08,
__LIBBPF_STRICT_LAST,
};
LIBBPF_API int libbpf_set_strict_mode(enum libbpf_strict_mode mode);
#ifdef __cplusplus
} /* extern "C" */
#endif
#endif /* __LIBBPF_LEGACY_BPF_H */