1// SPDX-License-Identifier: GPL-2.0
2/* Copyright (c) 2022 Meta Platforms, Inc. and affiliates. */
3
4#include <vmlinux.h>
5#include <bpf/bpf_tracing.h>
6#include <bpf/bpf_helpers.h>
7
8#include "cgrp_kfunc_common.h"
9
10char _license[] SEC("license") = "GPL";
11
12int err, pid, invocations;
13
14/* Prototype for all of the program trace events below:
15 *
16 * TRACE_EVENT(cgroup_mkdir,
17 * TP_PROTO(struct cgroup *cgrp, const char *path),
18 * TP_ARGS(cgrp, path)
19 */
20
21static bool is_test_kfunc_task(void)
22{
23 int cur_pid = bpf_get_current_pid_tgid() >> 32;
24 bool same = pid == cur_pid;
25
26 if (same)
27 __sync_fetch_and_add(&invocations, 1);
28
29 return same;
30}
31
32SEC("tp_btf/cgroup_mkdir")
33int BPF_PROG(test_cgrp_acquire_release_argument, struct cgroup *cgrp, const char *path)
34{
35 struct cgroup *acquired;
36
37 if (!is_test_kfunc_task())
38 return 0;
39
40 acquired = bpf_cgroup_acquire(cgrp);
41 if (!acquired)
42 err = 1;
43 else
44 bpf_cgroup_release(acquired);
45
46 return 0;
47}
48
49SEC("tp_btf/cgroup_mkdir")
50int BPF_PROG(test_cgrp_acquire_leave_in_map, struct cgroup *cgrp, const char *path)
51{
52 long status;
53
54 if (!is_test_kfunc_task())
55 return 0;
56
57 status = cgrps_kfunc_map_insert(cgrp: cgrp);
58 if (status)
59 err = 1;
60
61 return 0;
62}
63
64SEC("tp_btf/cgroup_mkdir")
65int BPF_PROG(test_cgrp_xchg_release, struct cgroup *cgrp, const char *path)
66{
67 struct cgroup *kptr, *cg;
68 struct __cgrps_kfunc_map_value *v;
69 long status;
70
71 if (!is_test_kfunc_task())
72 return 0;
73
74 status = cgrps_kfunc_map_insert(cgrp: cgrp);
75 if (status) {
76 err = 1;
77 return 0;
78 }
79
80 v = cgrps_kfunc_map_value_lookup(cgrp: cgrp);
81 if (!v) {
82 err = 2;
83 return 0;
84 }
85
86 kptr = v->cgrp;
87 if (!kptr) {
88 err = 4;
89 return 0;
90 }
91
92 cg = bpf_cgroup_ancestor(kptr, 1);
93 if (cg) /* verifier only check */
94 bpf_cgroup_release(cg);
95
96 kptr = bpf_kptr_xchg(&v->cgrp, NULL);
97 if (!kptr) {
98 err = 3;
99 return 0;
100 }
101
102 bpf_cgroup_release(kptr);
103
104 return 0;
105}
106
107SEC("tp_btf/cgroup_mkdir")
108int BPF_PROG(test_cgrp_get_release, struct cgroup *cgrp, const char *path)
109{
110 struct cgroup *kptr;
111 struct __cgrps_kfunc_map_value *v;
112 long status;
113
114 if (!is_test_kfunc_task())
115 return 0;
116
117 status = cgrps_kfunc_map_insert(cgrp: cgrp);
118 if (status) {
119 err = 1;
120 return 0;
121 }
122
123 v = cgrps_kfunc_map_value_lookup(cgrp: cgrp);
124 if (!v) {
125 err = 2;
126 return 0;
127 }
128
129 bpf_rcu_read_lock();
130 kptr = v->cgrp;
131 if (!kptr)
132 err = 3;
133 bpf_rcu_read_unlock();
134
135 return 0;
136}
137
138SEC("tp_btf/cgroup_mkdir")
139int BPF_PROG(test_cgrp_get_ancestors, struct cgroup *cgrp, const char *path)
140{
141 struct cgroup *self, *ancestor1, *invalid;
142
143 if (!is_test_kfunc_task())
144 return 0;
145
146 self = bpf_cgroup_ancestor(cgrp, cgrp->level);
147 if (!self) {
148 err = 1;
149 return 0;
150 }
151
152 if (self->self.id != cgrp->self.id) {
153 bpf_cgroup_release(self);
154 err = 2;
155 return 0;
156 }
157 bpf_cgroup_release(self);
158
159 ancestor1 = bpf_cgroup_ancestor(cgrp, cgrp->level - 1);
160 if (!ancestor1) {
161 err = 3;
162 return 0;
163 }
164 bpf_cgroup_release(ancestor1);
165
166 invalid = bpf_cgroup_ancestor(cgrp, 10000);
167 if (invalid) {
168 bpf_cgroup_release(invalid);
169 err = 4;
170 return 0;
171 }
172
173 invalid = bpf_cgroup_ancestor(cgrp, -1);
174 if (invalid) {
175 bpf_cgroup_release(invalid);
176 err = 5;
177 return 0;
178 }
179
180 return 0;
181}
182
183SEC("tp_btf/cgroup_mkdir")
184int BPF_PROG(test_cgrp_from_id, struct cgroup *cgrp, const char *path)
185{
186 struct cgroup *parent, *res;
187 u64 parent_cgid;
188
189 if (!is_test_kfunc_task())
190 return 0;
191
192 /* @cgrp's ID is not visible yet, let's test with the parent */
193 parent = bpf_cgroup_ancestor(cgrp, cgrp->level - 1);
194 if (!parent) {
195 err = 1;
196 return 0;
197 }
198
199 parent_cgid = parent->kn->id;
200 bpf_cgroup_release(parent);
201
202 res = bpf_cgroup_from_id(parent_cgid);
203 if (!res) {
204 err = 2;
205 return 0;
206 }
207
208 bpf_cgroup_release(res);
209
210 if (res != parent) {
211 err = 3;
212 return 0;
213 }
214
215 res = bpf_cgroup_from_id((u64)-1);
216 if (res) {
217 bpf_cgroup_release(res);
218 err = 4;
219 return 0;
220 }
221
222 return 0;
223}
224

source code of linux/tools/testing/selftests/bpf/progs/cgrp_kfunc_success.c