83 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			83 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
// SPDX-License-Identifier: GPL-2.0
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/* Copyright (c) 2021 Facebook */
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#include "vmlinux.h"
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#include <bpf/bpf_helpers.h>
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#include <bpf/bpf_tracing.h>
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struct my_key { long x; };
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struct my_value { long x; };
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struct {
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	__uint(type, BPF_MAP_TYPE_HASH);
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	__type(key, struct my_key);
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	__type(value, struct my_value);
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	__uint(max_entries, 16);
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} map1 SEC(".maps");
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 /* Matches map2 definition in linked_maps2.c. Order of the attributes doesn't
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  * matter.
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  */
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typedef struct {
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	__uint(max_entries, 8);
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	__type(key, int);
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	__type(value, int);
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	__uint(type, BPF_MAP_TYPE_ARRAY);
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} map2_t;
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extern map2_t map2 SEC(".maps");
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/* This should be the winning map definition, but we have no way of verifying,
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 * so we just make sure that it links and works without errors
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 */
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struct {
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	__uint(type, BPF_MAP_TYPE_ARRAY);
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	__type(key, int);
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	__type(value, int);
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	__uint(max_entries, 16);
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} map_weak __weak SEC(".maps");
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int output_first1;
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int output_second1;
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int output_weak1;
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SEC("raw_tp/sys_enter")
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int BPF_PROG(handler_enter1)
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{
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	/* update values with key = 1 */
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	int key = 1, val = 1;
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	struct my_key key_struct = { .x = 1 };
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	struct my_value val_struct = { .x = 1000 };
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	bpf_map_update_elem(&map1, &key_struct, &val_struct, 0);
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	bpf_map_update_elem(&map2, &key, &val, 0);
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	bpf_map_update_elem(&map_weak, &key, &val, 0);
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	return 0;
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}
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SEC("raw_tp/sys_exit")
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int BPF_PROG(handler_exit1)
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{
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	/* lookup values with key = 2, set in another file */
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	int key = 2, *val;
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	struct my_key key_struct = { .x = 2 };
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	struct my_value *value_struct;
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	value_struct = bpf_map_lookup_elem(&map1, &key_struct);
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	if (value_struct)
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		output_first1 = value_struct->x;
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	val = bpf_map_lookup_elem(&map2, &key);
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	if (val)
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		output_second1 = *val;
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	val = bpf_map_lookup_elem(&map_weak, &key);
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	if (val)
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		output_weak1 = *val;
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	return 0;
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}
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char LICENSE[] SEC("license") = "GPL";
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