Because the previous two commit replaced the bpf_load implementation of the user program with libbpf, the corresponding kernel program's MAP definition can be replaced with new BTF-defined map syntax. This commit only updates the samples which uses libbpf API for loading bpf program not with bpf_load. Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20200516040608.1377876-6-danieltimlee@gmail.com
		
			
				
	
	
		
			56 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			56 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/* Copyright (c) 2015 PLUMgrid, http://plumgrid.com
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 *
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 * This program is free software; you can redistribute it and/or
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 * modify it under the terms of version 2 of the GNU General Public
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 * License as published by the Free Software Foundation.
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 */
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#include <linux/ptrace.h>
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#include <linux/version.h>
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#include <uapi/linux/bpf.h>
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#include <bpf/bpf_helpers.h>
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#include <bpf/bpf_tracing.h>
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struct pair {
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	u64 val;
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	u64 ip;
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};
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struct {
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	__uint(type, BPF_MAP_TYPE_HASH);
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	__type(key, long);
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	__type(value, struct pair);
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	__uint(max_entries, 1000000);
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} my_map SEC(".maps");
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/* kprobe is NOT a stable ABI. If kernel internals change this bpf+kprobe
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 * example will no longer be meaningful
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 */
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SEC("kprobe/kmem_cache_free")
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int bpf_prog1(struct pt_regs *ctx)
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{
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	long ptr = PT_REGS_PARM2(ctx);
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	bpf_map_delete_elem(&my_map, &ptr);
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	return 0;
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}
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SEC("kretprobe/kmem_cache_alloc_node")
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int bpf_prog2(struct pt_regs *ctx)
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{
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	long ptr = PT_REGS_RC(ctx);
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	long ip = 0;
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	/* get ip address of kmem_cache_alloc_node() caller */
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	BPF_KRETPROBE_READ_RET_IP(ip, ctx);
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	struct pair v = {
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		.val = bpf_ktime_get_ns(),
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		.ip = ip,
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	};
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	bpf_map_update_elem(&my_map, &ptr, &v, BPF_ANY);
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	return 0;
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}
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char _license[] SEC("license") = "GPL";
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u32 _version SEC("version") = LINUX_VERSION_CODE;
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