enq_select_cpu.c

 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 "enq_select_cpu.bpf.skel.h"
12#include "scx_test.h"
13
14static enum scx_test_status setup(void **ctx)
15{
16	struct enq_select_cpu *skel;
17
18	skel = enq_select_cpu__open();
19	SCX_FAIL_IF(!skel, "Failed to open");
20	SCX_ENUM_INIT(skel);
21	SCX_FAIL_IF(enq_select_cpu__load(skel), "Failed to load skel");
22
23	*ctx = skel;
24
25	return SCX_TEST_PASS;
26}
27
28static int test_select_cpu_from_user(const struct enq_select_cpu *skel)
29{
30	int fd, ret;
31	__u64 args[1];
32
33	LIBBPF_OPTS(bpf_test_run_opts, attr,
34		.ctx_in = args,
35		.ctx_size_in = sizeof(args),
36	);
37
38	args[0] = getpid();
39	fd = bpf_program__fd(skel->progs.select_cpu_from_user);
40	if (fd < 0)
41		return fd;
42
43	ret = bpf_prog_test_run_opts(fd, &attr);
44	if (ret < 0)
45		return ret;
46
47	fprintf(stderr, "%s: CPU %d\n", __func__, attr.retval);
48
49	return 0;
50}
51
52static enum scx_test_status run(void *ctx)
53{
54	struct enq_select_cpu *skel = ctx;
55	struct bpf_link *link;
56
57	link = bpf_map__attach_struct_ops(skel->maps.enq_select_cpu_ops);
58	if (!link) {
59		SCX_ERR("Failed to attach scheduler");
60		return SCX_TEST_FAIL;
61	}
62
63	/* Pick an idle CPU from user-space */
64	SCX_FAIL_IF(test_select_cpu_from_user(skel), "Failed to pick idle CPU");
65
66	sleep(1);
67
68	SCX_EQ(skel->data->uei.kind, EXIT_KIND(SCX_EXIT_NONE));
69	bpf_link__destroy(link);
70
71	return SCX_TEST_PASS;
72}
73
74static void cleanup(void *ctx)
75{
76	struct enq_select_cpu *skel = ctx;
77
78	enq_select_cpu__destroy(skel);
79}
80
81struct scx_test enq_select_cpu = {
82	.name = "enq_select_cpu",
83	.description = "Verify scx_bpf_select_cpu_dfl() from multiple contexts",
84	.setup = setup,
85	.run = run,
86	.cleanup = cleanup,
87};
88REGISTER_SCX_TEST(&enq_select_cpu)