blob: eb0f8fdd14bf5b351daaca53359df335abd06421 [file] [log] [blame]
Alexei Starovoitov9811e352015-03-25 12:49:26 -07001/* Copyright (c) 2015 PLUMgrid, http://plumgrid.com
2 *
3 * This program is free software; you can redistribute it and/or
4 * modify it under the terms of version 2 of the GNU General Public
5 * License as published by the Free Software Foundation.
6 */
7#include <linux/ptrace.h>
8#include <linux/version.h>
9#include <uapi/linux/bpf.h>
Toke Høiland-Jørgensen7cf245a2020-01-20 14:06:49 +010010#include <bpf/bpf_helpers.h>
11#include <bpf/bpf_tracing.h>
Alexei Starovoitov9811e352015-03-25 12:49:26 -070012
13struct pair {
14 u64 val;
15 u64 ip;
16};
17
Daniel T. Lee59929cd2020-05-16 13:06:08 +090018struct {
19 __uint(type, BPF_MAP_TYPE_HASH);
20 __type(key, long);
21 __type(value, struct pair);
22 __uint(max_entries, 1000000);
23} my_map SEC(".maps");
Alexei Starovoitov9811e352015-03-25 12:49:26 -070024
25/* kprobe is NOT a stable ABI. If kernel internals change this bpf+kprobe
26 * example will no longer be meaningful
27 */
28SEC("kprobe/kmem_cache_free")
29int bpf_prog1(struct pt_regs *ctx)
30{
Michael Holzheud9125572015-07-06 16:20:07 +020031 long ptr = PT_REGS_PARM2(ctx);
Alexei Starovoitov9811e352015-03-25 12:49:26 -070032
33 bpf_map_delete_elem(&my_map, &ptr);
34 return 0;
35}
36
37SEC("kretprobe/kmem_cache_alloc_node")
38int bpf_prog2(struct pt_regs *ctx)
39{
Michael Holzheud9125572015-07-06 16:20:07 +020040 long ptr = PT_REGS_RC(ctx);
Alexei Starovoitov9811e352015-03-25 12:49:26 -070041 long ip = 0;
42
43 /* get ip address of kmem_cache_alloc_node() caller */
Naveen N. Rao138d6152016-04-04 22:31:34 +053044 BPF_KRETPROBE_READ_RET_IP(ip, ctx);
Alexei Starovoitov9811e352015-03-25 12:49:26 -070045
46 struct pair v = {
47 .val = bpf_ktime_get_ns(),
48 .ip = ip,
49 };
50
51 bpf_map_update_elem(&my_map, &ptr, &v, BPF_ANY);
52 return 0;
53}
54char _license[] SEC("license") = "GPL";
55u32 _version SEC("version") = LINUX_VERSION_CODE;