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_nodispatch.bpf.skel.h"
12#include "scx_test.h"
13
14#define NUM_CHILDREN 1028
15
16static enum scx_test_status setup(void **ctx)
17{
18	struct select_cpu_dfl_nodispatch *skel;
19
20	skel = select_cpu_dfl_nodispatch__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
27static enum scx_test_status run(void *ctx)
28{
29	struct select_cpu_dfl_nodispatch *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_nodispatch_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
57static void cleanup(void *ctx)
58{
59	struct select_cpu_dfl_nodispatch *skel = ctx;
60
61	select_cpu_dfl_nodispatch__destroy(skel);
62}
63
64struct scx_test select_cpu_dfl_nodispatch = {
65	.name = "select_cpu_dfl_nodispatch",
66	.description = "Verify behavior of scx_bpf_select_cpu_dfl() in "
67		       "ops.select_cpu()",
68	.setup = setup,
69	.run = run,
70	.cleanup = cleanup,
71};
72REGISTER_SCX_TEST(&select_cpu_dfl_nodispatch)