1 // SPDX-License-Identifier: GPL-2.0 2 // Copyright (c) 2019 Facebook 3 4 #include <linux/ptrace.h> 5 #include <linux/bpf.h> 6 #include <bpf/bpf_helpers.h> 7 #include <bpf/bpf_tracing.h> 8 9 struct { 10 __uint(type, BPF_MAP_TYPE_ARRAY); 11 __type(key, int); 12 __type(value, int); 13 __uint(max_entries, 1); 14 } my_pid_map SEC(".maps"); 15 16 struct { 17 __uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY); 18 __type(key, int); 19 __type(value, int); 20 } perf_buf_map SEC(".maps"); 21 22 SEC("tp/raw_syscalls/sys_enter") 23 int handle_sys_enter(void *ctx) 24 { 25 int zero = 0, *my_pid, cur_pid; 26 int cpu = bpf_get_smp_processor_id(); 27 28 my_pid = bpf_map_lookup_elem(&my_pid_map, &zero); 29 if (!my_pid) 30 return 1; 31 32 cur_pid = bpf_get_current_pid_tgid() >> 32; 33 if (cur_pid != *my_pid) 34 return 1; 35 36 bpf_perf_event_output(ctx, &perf_buf_map, BPF_F_CURRENT_CPU, 37 &cpu, sizeof(cpu)); 38 return 1; 39 } 40 41 char _license[] SEC("license") = "GPL"; 42