xref: /linux/tools/testing/selftests/bpf/prog_tests/timer_lockup.c (revision 170aafe35cb98e0f3fbacb446ea86389fbce22ea)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 #define _GNU_SOURCE
4 #include <sched.h>
5 #include <test_progs.h>
6 #include <pthread.h>
7 #include <network_helpers.h>
8 
9 #include "timer_lockup.skel.h"
10 
11 static long cpu;
12 static int *timer1_err;
13 static int *timer2_err;
14 static bool skip;
15 
16 volatile int k = 0;
17 
18 static void *timer_lockup_thread(void *arg)
19 {
20 	LIBBPF_OPTS(bpf_test_run_opts, opts,
21 		.data_in	= &pkt_v4,
22 		.data_size_in	= sizeof(pkt_v4),
23 		.repeat		= 1000,
24 	);
25 	int i, prog_fd = *(int *)arg;
26 	cpu_set_t cpuset;
27 
28 	CPU_ZERO(&cpuset);
29 	CPU_SET(__sync_fetch_and_add(&cpu, 1), &cpuset);
30 	ASSERT_OK(pthread_setaffinity_np(pthread_self(), sizeof(cpuset),
31 				         &cpuset),
32 		  "cpu affinity");
33 
34 	for (i = 0; !READ_ONCE(*timer1_err) && !READ_ONCE(*timer2_err); i++) {
35 		bpf_prog_test_run_opts(prog_fd, &opts);
36 		/* Skip the test if we can't reproduce the race in a reasonable
37 		 * amount of time.
38 		 */
39 		if (i > 50) {
40 			WRITE_ONCE(skip, true);
41 			break;
42 		}
43 	}
44 
45 	return NULL;
46 }
47 
48 void test_timer_lockup(void)
49 {
50 	int timer1_prog, timer2_prog;
51 	struct timer_lockup *skel;
52 	pthread_t thrds[2];
53 	void *ret;
54 
55 	skel = timer_lockup__open_and_load();
56 	if (!ASSERT_OK_PTR(skel, "timer_lockup__open_and_load"))
57 		return;
58 
59 	timer1_prog = bpf_program__fd(skel->progs.timer1_prog);
60 	timer2_prog = bpf_program__fd(skel->progs.timer2_prog);
61 
62 	timer1_err = &skel->bss->timer1_err;
63 	timer2_err = &skel->bss->timer2_err;
64 
65 	if (!ASSERT_OK(pthread_create(&thrds[0], NULL, timer_lockup_thread,
66 				      &timer1_prog),
67 		       "pthread_create thread1"))
68 		goto out;
69 	if (!ASSERT_OK(pthread_create(&thrds[1], NULL, timer_lockup_thread,
70 				      &timer2_prog),
71 		       "pthread_create thread2")) {
72 		pthread_exit(&thrds[0]);
73 		goto out;
74 	}
75 
76 	pthread_join(thrds[1], &ret);
77 	pthread_join(thrds[0], &ret);
78 
79 	if (skip) {
80 		test__skip();
81 		goto out;
82 	}
83 
84 	if (*timer1_err != -EDEADLK && *timer1_err != 0)
85 		ASSERT_FAIL("timer1_err bad value");
86 	if (*timer2_err != -EDEADLK && *timer2_err != 0)
87 		ASSERT_FAIL("timer2_err bad value");
88 out:
89 	timer_lockup__destroy(skel);
90 	return;
91 }
92