/* Copyright (c) 2015 PLUMgrid, http://plumgrid.com * * This program is free software; you can redistribute it and/or * modify it under the terms of version 2 of the GNU General Public * License as published by the Free Software Foundation. */ #include <linux/ptrace.h> #include <linux/version.h> #include <uapi/linux/bpf.h> #include "bpf_helpers.h" struct pair { u64 val; u64 ip; }; struct bpf_map_def SEC("maps") my_map = { .type = BPF_MAP_TYPE_HASH, .key_size = sizeof(long), .value_size = sizeof(struct pair), .max_entries = 1000000, }; /* kprobe is NOT a stable ABI. If kernel internals change this bpf+kprobe * example will no longer be meaningful */ SEC("kprobe/kmem_cache_free") int bpf_prog1(struct pt_regs *ctx) { long ptr = PT_REGS_PARM2(ctx); bpf_map_delete_elem(&my_map, &ptr); return 0; } SEC("kretprobe/kmem_cache_alloc_node") int bpf_prog2(struct pt_regs *ctx) { long ptr = PT_REGS_RC(ctx); long ip = 0; /* get ip address of kmem_cache_alloc_node() caller */ BPF_KRETPROBE_READ_RET_IP(ip, ctx); struct pair v = { .val = bpf_ktime_get_ns(), .ip = ip, }; bpf_map_update_elem(&my_map, &ptr, &v, BPF_ANY); return 0; } char _license[] SEC("license") = "GPL"; u32 _version SEC("version") = LINUX_VERSION_CODE;