Book a Demo!
CoCalc Logo Icon
StoreFeaturesDocsShareSupportNewsAboutPoliciesSign UpSign In
torvalds
GitHub Repository: torvalds/linux
 Path: blob/master/samples/bpf/spintest.bpf.c
25924 views
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


62