// 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_PREEMPTION __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_PREEMPTION) 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; }