LXR linux/samples/bpf/spintest

   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 <linux/skbuff.h>
   8#include <linux/netdevice.h>
   9#include <linux/version.h>
  10#include <uapi/linux/bpf.h>
  11#include <uapi/linux/perf_event.h>
  12#include "bpf_helpers.h"
  13
  14struct bpf_map_def SEC("maps") my_map = {
  15        .type = BPF_MAP_TYPE_HASH,
  16        .key_size = sizeof(long),
  17        .value_size = sizeof(long),
  18        .max_entries = 1024,
  19};
  20struct bpf_map_def SEC("maps") my_map2 = {
  21        .type = BPF_MAP_TYPE_PERCPU_HASH,
  22        .key_size = sizeof(long),
  23        .value_size = sizeof(long),
  24        .max_entries = 1024,
  25};
  26
  27struct bpf_map_def SEC("maps") stackmap = {
  28        .type = BPF_MAP_TYPE_STACK_TRACE,
  29        .key_size = sizeof(u32),
  30        .value_size = PERF_MAX_STACK_DEPTH * sizeof(u64),
  31        .max_entries = 10000,
  32};
  33
  34#define PROG(foo) \
  35int foo(struct pt_regs *ctx) \
  36{ \
  37        long v = PT_REGS_IP(ctx), *val; \
  38\
  39        val = bpf_map_lookup_elem(&my_map, &v); \
  40        bpf_map_update_elem(&my_map, &v, &v, BPF_ANY); \
  41        bpf_map_update_elem(&my_map2, &v, &v, BPF_ANY); \
  42        bpf_map_delete_elem(&my_map2, &v); \
  43        bpf_get_stackid(ctx, &stackmap, BPF_F_REUSE_STACKID); \
  44        return 0; \
  45}
  46
  47/* add kprobes to all possible *spin* functions */
  48SEC("kprobe/spin_unlock")PROG(p1)
  49SEC("kprobe/spin_lock")PROG(p2)
  50SEC("kprobe/mutex_spin_on_owner")PROG(p3)
  51SEC("kprobe/rwsem_spin_on_owner")PROG(p4)
  52SEC("kprobe/spin_unlock_irqrestore")PROG(p5)
  53SEC("kprobe/_raw_spin_unlock_irqrestore")PROG(p6)
  54SEC("kprobe/_raw_spin_unlock_bh")PROG(p7)
  55SEC("kprobe/_raw_spin_unlock")PROG(p8)
  56SEC("kprobe/_raw_spin_lock_irqsave")PROG(p9)
  57SEC("kprobe/_raw_spin_trylock_bh")PROG(p10)
  58SEC("kprobe/_raw_spin_lock_irq")PROG(p11)
  59SEC("kprobe/_raw_spin_trylock")PROG(p12)
  60SEC("kprobe/_raw_spin_lock")PROG(p13)
  61SEC("kprobe/_raw_spin_lock_bh")PROG(p14)
  62/* and to inner bpf helpers */
  63SEC("kprobe/htab_map_update_elem")PROG(p15)
  64SEC("kprobe/__htab_percpu_map_update_elem")PROG(p16)
  65SEC("kprobe/htab_map_alloc")PROG(p17)
  66
  67char _license[] SEC("license") = "GPL";
  68u32 _version SEC("version") = LINUX_VERSION_CODE;
  69