1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Copyright (c) 2023 Meta Platforms, Inc. and affiliates.
4 * Copyright (c) 2023 David Vernet <dvernet@meta.com>
5 * Copyright (c) 2023 Tejun Heo <tj@kernel.org>
6 */
7 #include <bpf/bpf.h>
8 #include <scx/common.h>
9 #include <sys/wait.h>
10 #include <unistd.h>
11 #include "select_cpu_dfl.bpf.skel.h"
12 #include "scx_test.h"
13
14 #define NUM_CHILDREN 1028
15
setup(void ** ctx)16 static enum scx_test_status setup(void **ctx)
17 {
18 struct select_cpu_dfl *skel;
19
20 skel = select_cpu_dfl__open_and_load();
21 SCX_FAIL_IF(!skel, "Failed to open and load skel");
22 *ctx = skel;
23
24 return SCX_TEST_PASS;
25 }
26
run(void * ctx)27 static enum scx_test_status run(void *ctx)
28 {
29 struct select_cpu_dfl *skel = ctx;
30 struct bpf_link *link;
31 pid_t pids[NUM_CHILDREN];
32 int i, status;
33
34 link = bpf_map__attach_struct_ops(skel->maps.select_cpu_dfl_ops);
35 SCX_FAIL_IF(!link, "Failed to attach scheduler");
36
37 for (i = 0; i < NUM_CHILDREN; i++) {
38 pids[i] = fork();
39 if (pids[i] == 0) {
40 sleep(1);
41 exit(0);
42 }
43 }
44
45 for (i = 0; i < NUM_CHILDREN; i++) {
46 SCX_EQ(waitpid(pids[i], &status, 0), pids[i]);
47 SCX_EQ(status, 0);
48 }
49
50 SCX_ASSERT(!skel->bss->saw_local);
51
52 bpf_link__destroy(link);
53
54 return SCX_TEST_PASS;
55 }
56
cleanup(void * ctx)57 static void cleanup(void *ctx)
58 {
59 struct select_cpu_dfl *skel = ctx;
60
61 select_cpu_dfl__destroy(skel);
62 }
63
64 struct scx_test select_cpu_dfl = {
65 .name = "select_cpu_dfl",
66 .description = "Verify the default ops.select_cpu() dispatches tasks "
67 "when idles cores are found, and skips ops.enqueue()",
68 .setup = setup,
69 .run = run,
70 .cleanup = cleanup,
71 };
72 REGISTER_SCX_TEST(&select_cpu_dfl)
73