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_dispatch.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_dispatch *skel;
19
20	skel = select_cpu_dispatch__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_dispatch *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_dispatch_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	bpf_link__destroy(link);
51
52	return SCX_TEST_PASS;
53}
54
55static void cleanup(void *ctx)
56{
57	struct select_cpu_dispatch *skel = ctx;
58
59	select_cpu_dispatch__destroy(skel);
60}
61
62struct scx_test select_cpu_dispatch = {
63	.name = "select_cpu_dispatch",
64	.description = "Test direct dispatching to built-in DSQs from "
65		       "ops.select_cpu()",
66	.setup = setup,
67	.run = run,
68	.cleanup = cleanup,
69};
70REGISTER_SCX_TEST(&select_cpu_dispatch)