xref: /linux/tools/testing/selftests/sched_ext/hotplug.bpf.c (revision a5db7817af780db6a7f290c79677eff4fd13c5fa)
1*a5db7817SDavid Vernet /* SPDX-License-Identifier: GPL-2.0 */
2*a5db7817SDavid Vernet /*
3*a5db7817SDavid Vernet  * Copyright (c) 2024 Meta Platforms, Inc. and affiliates.
4*a5db7817SDavid Vernet  * Copyright (c) 2024 David Vernet <dvernet@meta.com>
5*a5db7817SDavid Vernet  */
6*a5db7817SDavid Vernet 
7*a5db7817SDavid Vernet #include <scx/common.bpf.h>
8*a5db7817SDavid Vernet 
9*a5db7817SDavid Vernet char _license[] SEC("license") = "GPL";
10*a5db7817SDavid Vernet 
11*a5db7817SDavid Vernet #include "hotplug_test.h"
12*a5db7817SDavid Vernet 
13*a5db7817SDavid Vernet UEI_DEFINE(uei);
14*a5db7817SDavid Vernet 
15*a5db7817SDavid Vernet void BPF_STRUCT_OPS(hotplug_exit, struct scx_exit_info *ei)
16*a5db7817SDavid Vernet {
17*a5db7817SDavid Vernet 	UEI_RECORD(uei, ei);
18*a5db7817SDavid Vernet }
19*a5db7817SDavid Vernet 
20*a5db7817SDavid Vernet static void exit_from_hotplug(s32 cpu, bool onlining)
21*a5db7817SDavid Vernet {
22*a5db7817SDavid Vernet 	/*
23*a5db7817SDavid Vernet 	 * Ignored, just used to verify that we can invoke blocking kfuncs
24*a5db7817SDavid Vernet 	 * from the hotplug path.
25*a5db7817SDavid Vernet 	 */
26*a5db7817SDavid Vernet 	scx_bpf_create_dsq(0, -1);
27*a5db7817SDavid Vernet 
28*a5db7817SDavid Vernet 	s64 code = SCX_ECODE_ACT_RESTART | HOTPLUG_EXIT_RSN;
29*a5db7817SDavid Vernet 
30*a5db7817SDavid Vernet 	if (onlining)
31*a5db7817SDavid Vernet 		code |= HOTPLUG_ONLINING;
32*a5db7817SDavid Vernet 
33*a5db7817SDavid Vernet 	scx_bpf_exit(code, "hotplug event detected (%d going %s)", cpu,
34*a5db7817SDavid Vernet 		     onlining ? "online" : "offline");
35*a5db7817SDavid Vernet }
36*a5db7817SDavid Vernet 
37*a5db7817SDavid Vernet void BPF_STRUCT_OPS_SLEEPABLE(hotplug_cpu_online, s32 cpu)
38*a5db7817SDavid Vernet {
39*a5db7817SDavid Vernet 	exit_from_hotplug(cpu, true);
40*a5db7817SDavid Vernet }
41*a5db7817SDavid Vernet 
42*a5db7817SDavid Vernet void BPF_STRUCT_OPS_SLEEPABLE(hotplug_cpu_offline, s32 cpu)
43*a5db7817SDavid Vernet {
44*a5db7817SDavid Vernet 	exit_from_hotplug(cpu, false);
45*a5db7817SDavid Vernet }
46*a5db7817SDavid Vernet 
47*a5db7817SDavid Vernet SEC(".struct_ops.link")
48*a5db7817SDavid Vernet struct sched_ext_ops hotplug_cb_ops = {
49*a5db7817SDavid Vernet 	.cpu_online		= hotplug_cpu_online,
50*a5db7817SDavid Vernet 	.cpu_offline		= hotplug_cpu_offline,
51*a5db7817SDavid Vernet 	.exit			= hotplug_exit,
52*a5db7817SDavid Vernet 	.name			= "hotplug_cbs",
53*a5db7817SDavid Vernet 	.timeout_ms		= 1000U,
54*a5db7817SDavid Vernet };
55*a5db7817SDavid Vernet 
56*a5db7817SDavid Vernet SEC(".struct_ops.link")
57*a5db7817SDavid Vernet struct sched_ext_ops hotplug_nocb_ops = {
58*a5db7817SDavid Vernet 	.exit			= hotplug_exit,
59*a5db7817SDavid Vernet 	.name			= "hotplug_nocbs",
60*a5db7817SDavid Vernet 	.timeout_ms		= 1000U,
61*a5db7817SDavid Vernet };
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