| // SPDX-License-Identifier: GPL-2.0 |
| /* Copyright (C) 2022. Huawei Technologies Co., Ltd */ |
| #include "vmlinux.h" |
| #include <bpf/bpf_helpers.h> |
| #include <bpf/bpf_tracing.h> |
| |
| extern bool CONFIG_PREEMPT __kconfig __weak; |
| extern const int bpf_task_storage_busy __ksym; |
| |
| char _license[] SEC("license") = "GPL"; |
| |
| int pid = 0; |
| int busy = 0; |
| |
| struct { |
| __uint(type, BPF_MAP_TYPE_TASK_STORAGE); |
| __uint(map_flags, BPF_F_NO_PREALLOC); |
| __type(key, int); |
| __type(value, long); |
| } task SEC(".maps"); |
| |
| SEC("raw_tp/sys_enter") |
| int BPF_PROG(read_bpf_task_storage_busy) |
| { |
| int *value; |
| |
| if (!CONFIG_PREEMPT) |
| return 0; |
| |
| if (bpf_get_current_pid_tgid() >> 32 != pid) |
| return 0; |
| |
| value = bpf_this_cpu_ptr(&bpf_task_storage_busy); |
| if (value) |
| busy = *value; |
| |
| return 0; |
| } |