1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2020 Facebook
3 #include "vmlinux.h"
4 #include <bpf/bpf_helpers.h>
5
6 #ifndef PERF_MAX_STACK_DEPTH
7 #define PERF_MAX_STACK_DEPTH 127
8 #endif
9
10 typedef __u64 stack_trace_t[PERF_MAX_STACK_DEPTH];
11 struct {
12 __uint(type, BPF_MAP_TYPE_STACK_TRACE);
13 __uint(max_entries, 16384);
14 __type(key, __u32);
15 __type(value, stack_trace_t);
16 } stackmap SEC(".maps");
17
18 struct {
19 __uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
20 __uint(max_entries, 1);
21 __type(key, __u32);
22 __type(value, stack_trace_t);
23 } stackdata_map SEC(".maps");
24
25 long stackid_kernel = 1;
26 long stackid_user = 1;
27 long stack_kernel = 1;
28 long stack_user = 1;
29
30 SEC("perf_event")
31 int oncpu(void *ctx)
32 {
33 stack_trace_t *trace;
34 __u32 key = 0;
35 long val;
36
37 val = bpf_get_stackid(ctx, &stackmap, 0);
38 if (val >= 0)
39 stackid_kernel = 2;
40 val = bpf_get_stackid(ctx, &stackmap, BPF_F_USER_STACK);
41 if (val >= 0)
42 stackid_user = 2;
43
44 trace = bpf_map_lookup_elem(&stackdata_map, &key);
45 if (!trace)
46 return 0;
47
48 val = bpf_get_stack(ctx, trace, sizeof(stack_trace_t), 0);
49 if (val > 0)
50 stack_kernel = 2;
51
52 val = bpf_get_stack(ctx, trace, sizeof(stack_trace_t), BPF_F_USER_STACK);
53 if (val > 0)
54 stack_user = 2;
55
56 return 0;
57 }
58
59 char LICENSE[] SEC("license") = "GPL";
60
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.