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.bpf.skel.h" 12 #include "scx_test.h" 13 14 #define NUM_CHILDREN 1028 15 16 static enum scx_test_status setup(void **ctx) 17 { 18 struct select_cpu_dfl *skel; 19 20 skel = select_cpu_dfl__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 27 static enum scx_test_status run(void *ctx) 28 { 29 struct select_cpu_dfl *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_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 57 static void cleanup(void *ctx) 58 { 59 struct select_cpu_dfl *skel = ctx; 60 61 select_cpu_dfl__destroy(skel); 62 } 63 64 struct scx_test select_cpu_dfl = { 65 .name = "select_cpu_dfl", 66 .description = "Verify the default ops.select_cpu() dispatches tasks " 67 "when idles cores are found, and skips ops.enqueue()", 68 .setup = setup, 69 .run = run, 70 .cleanup = cleanup, 71 }; 72 REGISTER_SCX_TEST(&select_cpu_dfl) 73