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1// SPDX-License-Identifier: GPL-2.02// Copyright (c) 2020 Facebook3#include "vmlinux.h"4#include <bpf/bpf_helpers.h>5 6#ifndef PERF_MAX_STACK_DEPTH7#define PERF_MAX_STACK_DEPTH 1278#endif9 10typedef __u64 stack_trace_t[PERF_MAX_STACK_DEPTH];11struct {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 18struct {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 25long stackid_kernel = 1;26long stackid_user = 1;27long stack_kernel = 1;28long stack_user = 1;29 30SEC("perf_event")31int 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 59char LICENSE[] SEC("license") = "GPL";60