/* SPDX-License-Identifier: GPL-2.0 *//* * Copyright (c) 2023 Meta Platforms, Inc. and affiliates. * Copyright (c) 2023 David Vernet <dvernet@meta.com> * Copyright (c) 2023 Tejun Heo <tj@kernel.org> */#include <bpf/bpf.h>#include <scx/common.h>#include <sys/wait.h>#include <unistd.h>#include "select_cpu_dispatch.bpf.skel.h"#include "scx_test.h" #define NUM_CHILDREN 1028 static enum scx_test_status setup(void **ctx){	struct select_cpu_dispatch *skel; 	skel = select_cpu_dispatch__open();	SCX_FAIL_IF(!skel, "Failed to open");	SCX_ENUM_INIT(skel);	SCX_FAIL_IF(select_cpu_dispatch__load(skel), "Failed to load skel"); 	*ctx = skel; 	return SCX_TEST_PASS;} static enum scx_test_status run(void *ctx){	struct select_cpu_dispatch *skel = ctx;	struct bpf_link *link;	pid_t pids[NUM_CHILDREN];	int i, status; 	link = bpf_map__attach_struct_ops(skel->maps.select_cpu_dispatch_ops);	SCX_FAIL_IF(!link, "Failed to attach scheduler"); 	for (i = 0; i < NUM_CHILDREN; i++) {		pids[i] = fork();		if (pids[i] == 0) {			sleep(1);			exit(0);		}	} 	for (i = 0; i < NUM_CHILDREN; i++) {		SCX_EQ(waitpid(pids[i], &status, 0), pids[i]);		SCX_EQ(status, 0);	} 	bpf_link__destroy(link); 	return SCX_TEST_PASS;} static void cleanup(void *ctx){	struct select_cpu_dispatch *skel = ctx; 	select_cpu_dispatch__destroy(skel);} struct scx_test select_cpu_dispatch = {	.name = "select_cpu_dispatch",	.description = "Test direct dispatching to built-in DSQs from "		       "ops.select_cpu()",	.setup = setup,	.run = run,	.cleanup = cleanup,};REGISTER_SCX_TEST(&select_cpu_dispatch)