1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * A scheduler that validates the behavior of direct dispatching with a default 4 * select_cpu implementation. 5 * 6 * Copyright (c) 2023 Meta Platforms, Inc. and affiliates. 7 * Copyright (c) 2023 David Vernet <dvernet@meta.com> 8 * Copyright (c) 2023 Tejun Heo <tj@kernel.org> 9 */ 10 11 #include <scx/common.bpf.h> 12 13 char _license[] SEC("license") = "GPL"; 14 15 bool saw_local = false; 16 17 static bool task_is_test(const struct task_struct *p) 18 { 19 return !bpf_strncmp(p->comm, 9, "select_cpu"); 20 } 21 22 void BPF_STRUCT_OPS(select_cpu_dfl_enqueue, struct task_struct *p, 23 u64 enq_flags) 24 { 25 const struct cpumask *idle_mask = scx_bpf_get_idle_cpumask(); 26 27 if (task_is_test(p) && 28 bpf_cpumask_test_cpu(scx_bpf_task_cpu(p), idle_mask)) { 29 saw_local = true; 30 } 31 scx_bpf_put_idle_cpumask(idle_mask); 32 33 scx_bpf_dispatch(p, SCX_DSQ_GLOBAL, SCX_SLICE_DFL, enq_flags); 34 } 35 36 SEC(".struct_ops.link") 37 struct sched_ext_ops select_cpu_dfl_ops = { 38 .enqueue = select_cpu_dfl_enqueue, 39 .name = "select_cpu_dfl", 40 }; 41