linux-zen-desktop/tools/perf/util/bpf-utils.h

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2023-08-30 17:31:07 +02:00
/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
#ifndef __PERF_BPF_UTILS_H
#define __PERF_BPF_UTILS_H
#define ptr_to_u64(ptr) ((__u64)(unsigned long)(ptr))
#ifdef HAVE_LIBBPF_SUPPORT
#include <bpf/libbpf.h>
/*
* Get bpf_prog_info in continuous memory
*
* struct bpf_prog_info has multiple arrays. The user has option to choose
* arrays to fetch from kernel. The following APIs provide an uniform way to
* fetch these data. All arrays in bpf_prog_info are stored in a single
* continuous memory region. This makes it easy to store the info in a
* file.
*
* Before writing perf_bpil to files, it is necessary to
* translate pointers in bpf_prog_info to offsets. Helper functions
* bpil_addr_to_offs() and bpil_offs_to_addr()
* are introduced to switch between pointers and offsets.
*
* Examples:
* # To fetch map_ids and prog_tags:
* __u64 arrays = (1UL << PERF_BPIL_MAP_IDS) |
* (1UL << PERF_BPIL_PROG_TAGS);
* struct perf_bpil *info_linear =
* get_bpf_prog_info_linear(fd, arrays);
*
* # To save data in file
* bpil_addr_to_offs(info_linear);
* write(f, info_linear, sizeof(*info_linear) + info_linear->data_len);
*
* # To read data from file
* read(f, info_linear, <proper_size>);
* bpil_offs_to_addr(info_linear);
*/
enum perf_bpil_array_types {
PERF_BPIL_FIRST_ARRAY = 0,
PERF_BPIL_JITED_INSNS = 0,
PERF_BPIL_XLATED_INSNS,
PERF_BPIL_MAP_IDS,
PERF_BPIL_JITED_KSYMS,
PERF_BPIL_JITED_FUNC_LENS,
PERF_BPIL_FUNC_INFO,
PERF_BPIL_LINE_INFO,
PERF_BPIL_JITED_LINE_INFO,
PERF_BPIL_PROG_TAGS,
PERF_BPIL_LAST_ARRAY,
};
struct perf_bpil {
/* size of struct bpf_prog_info, when the tool is compiled */
__u32 info_len;
/* total bytes allocated for data, round up to 8 bytes */
__u32 data_len;
/* which arrays are included in data */
__u64 arrays;
struct bpf_prog_info info;
__u8 data[];
};
struct perf_bpil *
get_bpf_prog_info_linear(int fd, __u64 arrays);
void
bpil_addr_to_offs(struct perf_bpil *info_linear);
void
bpil_offs_to_addr(struct perf_bpil *info_linear);
#endif /* HAVE_LIBBPF_SUPPORT */
#endif /* __PERF_BPF_UTILS_H */