xref: /linux/tools/testing/selftests/bpf/prog_tests/tp_attach_query.c (revision 95298d63c67673c654c08952672d016212b26054)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <test_progs.h>
3 
4 void test_tp_attach_query(void)
5 {
6 	const int num_progs = 3;
7 	int i, j, bytes, efd, err, prog_fd[num_progs], pmu_fd[num_progs];
8 	__u32 duration = 0, info_len, saved_prog_ids[num_progs];
9 	const char *file = "./test_tracepoint.o";
10 	struct perf_event_query_bpf *query;
11 	struct perf_event_attr attr = {};
12 	struct bpf_object *obj[num_progs];
13 	struct bpf_prog_info prog_info;
14 	char buf[256];
15 
16 	for (i = 0; i < num_progs; i++)
17 		obj[i] = NULL;
18 
19 	snprintf(buf, sizeof(buf),
20 		 "/sys/kernel/debug/tracing/events/sched/sched_switch/id");
21 	efd = open(buf, O_RDONLY, 0);
22 	if (CHECK(efd < 0, "open", "err %d errno %d\n", efd, errno))
23 		return;
24 	bytes = read(efd, buf, sizeof(buf));
25 	close(efd);
26 	if (CHECK(bytes <= 0 || bytes >= sizeof(buf),
27 		  "read", "bytes %d errno %d\n", bytes, errno))
28 		return;
29 
30 	attr.config = strtol(buf, NULL, 0);
31 	attr.type = PERF_TYPE_TRACEPOINT;
32 	attr.sample_type = PERF_SAMPLE_RAW | PERF_SAMPLE_CALLCHAIN;
33 	attr.sample_period = 1;
34 	attr.wakeup_events = 1;
35 
36 	query = malloc(sizeof(*query) + sizeof(__u32) * num_progs);
37 	for (i = 0; i < num_progs; i++) {
38 		err = bpf_prog_load(file, BPF_PROG_TYPE_TRACEPOINT, &obj[i],
39 				    &prog_fd[i]);
40 		if (CHECK(err, "prog_load", "err %d errno %d\n", err, errno))
41 			goto cleanup1;
42 
43 		bzero(&prog_info, sizeof(prog_info));
44 		prog_info.jited_prog_len = 0;
45 		prog_info.xlated_prog_len = 0;
46 		prog_info.nr_map_ids = 0;
47 		info_len = sizeof(prog_info);
48 		err = bpf_obj_get_info_by_fd(prog_fd[i], &prog_info, &info_len);
49 		if (CHECK(err, "bpf_obj_get_info_by_fd", "err %d errno %d\n",
50 			  err, errno))
51 			goto cleanup1;
52 		saved_prog_ids[i] = prog_info.id;
53 
54 		pmu_fd[i] = syscall(__NR_perf_event_open, &attr, -1 /* pid */,
55 				    0 /* cpu 0 */, -1 /* group id */,
56 				    0 /* flags */);
57 		if (CHECK(pmu_fd[i] < 0, "perf_event_open", "err %d errno %d\n",
58 			  pmu_fd[i], errno))
59 			goto cleanup2;
60 		err = ioctl(pmu_fd[i], PERF_EVENT_IOC_ENABLE, 0);
61 		if (CHECK(err, "perf_event_ioc_enable", "err %d errno %d\n",
62 			  err, errno))
63 			goto cleanup3;
64 
65 		if (i == 0) {
66 			/* check NULL prog array query */
67 			query->ids_len = num_progs;
68 			err = ioctl(pmu_fd[i], PERF_EVENT_IOC_QUERY_BPF, query);
69 			if (CHECK(err || query->prog_cnt != 0,
70 				  "perf_event_ioc_query_bpf",
71 				  "err %d errno %d query->prog_cnt %u\n",
72 				  err, errno, query->prog_cnt))
73 				goto cleanup3;
74 		}
75 
76 		err = ioctl(pmu_fd[i], PERF_EVENT_IOC_SET_BPF, prog_fd[i]);
77 		if (CHECK(err, "perf_event_ioc_set_bpf", "err %d errno %d\n",
78 			  err, errno))
79 			goto cleanup3;
80 
81 		if (i == 1) {
82 			/* try to get # of programs only */
83 			query->ids_len = 0;
84 			err = ioctl(pmu_fd[i], PERF_EVENT_IOC_QUERY_BPF, query);
85 			if (CHECK(err || query->prog_cnt != 2,
86 				  "perf_event_ioc_query_bpf",
87 				  "err %d errno %d query->prog_cnt %u\n",
88 				  err, errno, query->prog_cnt))
89 				goto cleanup3;
90 
91 			/* try a few negative tests */
92 			/* invalid query pointer */
93 			err = ioctl(pmu_fd[i], PERF_EVENT_IOC_QUERY_BPF,
94 				    (struct perf_event_query_bpf *)0x1);
95 			if (CHECK(!err || errno != EFAULT,
96 				  "perf_event_ioc_query_bpf",
97 				  "err %d errno %d\n", err, errno))
98 				goto cleanup3;
99 
100 			/* no enough space */
101 			query->ids_len = 1;
102 			err = ioctl(pmu_fd[i], PERF_EVENT_IOC_QUERY_BPF, query);
103 			if (CHECK(!err || errno != ENOSPC || query->prog_cnt != 2,
104 				  "perf_event_ioc_query_bpf",
105 				  "err %d errno %d query->prog_cnt %u\n",
106 				  err, errno, query->prog_cnt))
107 				goto cleanup3;
108 		}
109 
110 		query->ids_len = num_progs;
111 		err = ioctl(pmu_fd[i], PERF_EVENT_IOC_QUERY_BPF, query);
112 		if (CHECK(err || query->prog_cnt != (i + 1),
113 			  "perf_event_ioc_query_bpf",
114 			  "err %d errno %d query->prog_cnt %u\n",
115 			  err, errno, query->prog_cnt))
116 			goto cleanup3;
117 		for (j = 0; j < i + 1; j++)
118 			if (CHECK(saved_prog_ids[j] != query->ids[j],
119 				  "perf_event_ioc_query_bpf",
120 				  "#%d saved_prog_id %x query prog_id %x\n",
121 				  j, saved_prog_ids[j], query->ids[j]))
122 				goto cleanup3;
123 	}
124 
125 	i = num_progs - 1;
126 	for (; i >= 0; i--) {
127  cleanup3:
128 		ioctl(pmu_fd[i], PERF_EVENT_IOC_DISABLE);
129  cleanup2:
130 		close(pmu_fd[i]);
131  cleanup1:
132 		bpf_object__close(obj[i]);
133 	}
134 	free(query);
135 }
136