1 /* Copyright (c) 2016, Facebook 2 * 3 * This program is free software; you can redistribute it and/or 4 * modify it under the terms of version 2 of the GNU General Public 5 * License as published by the Free Software Foundation. 6 */ 7 #include "vmlinux.h" 8 #include <linux/version.h> 9 #include <bpf/bpf_helpers.h> 10 #include <bpf/bpf_tracing.h> 11 12 #ifndef PERF_MAX_STACK_DEPTH 13 #define PERF_MAX_STACK_DEPTH 127 14 #endif 15 16 struct { 17 __uint(type, BPF_MAP_TYPE_HASH); 18 __type(key, long); 19 __type(value, long); 20 __uint(max_entries, 1024); 21 } my_map SEC(".maps"); 22 struct { 23 __uint(type, BPF_MAP_TYPE_PERCPU_HASH); 24 __uint(key_size, sizeof(long)); 25 __uint(value_size, sizeof(long)); 26 __uint(max_entries, 1024); 27 } my_map2 SEC(".maps"); 28 29 struct { 30 __uint(type, BPF_MAP_TYPE_STACK_TRACE); 31 __uint(key_size, sizeof(u32)); 32 __uint(value_size, PERF_MAX_STACK_DEPTH * sizeof(u64)); 33 __uint(max_entries, 10000); 34 } stackmap SEC(".maps"); 35 36 #define PROG(foo) \ 37 int foo(struct pt_regs *ctx) \ 38 { \ 39 long v = PT_REGS_IP(ctx), *val; \ 40 \ 41 val = bpf_map_lookup_elem(&my_map, &v); \ 42 bpf_map_update_elem(&my_map, &v, &v, BPF_ANY); \ 43 bpf_map_update_elem(&my_map2, &v, &v, BPF_ANY); \ 44 bpf_map_delete_elem(&my_map2, &v); \ 45 bpf_get_stackid(ctx, &stackmap, BPF_F_REUSE_STACKID); \ 46 return 0; \ 47 } 48 49 /* add kprobes to all possible *spin* functions */ 50 SEC("kprobe.multi/spin_*lock*")PROG(spin_lock) 51 SEC("kprobe.multi/*_spin_on_owner")PROG(spin_on_owner) 52 SEC("kprobe.multi/_raw_spin_*lock*")PROG(raw_spin_lock) 53 54 /* and to inner bpf helpers */ 55 SEC("kprobe/htab_map_update_elem")PROG(p15) 56 SEC("kprobe/__htab_percpu_map_update_elem")PROG(p16) 57 SEC("kprobe/htab_map_alloc")PROG(p17) 58 59 char _license[] SEC("license") = "GPL"; 60 u32 _version SEC("version") = LINUX_VERSION_CODE; 61