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1// SPDX-License-Identifier: GPL-2.02/* Copyright (c) 2024 Meta Platforms, Inc. and affiliates. */3#define BPF_NO_KFUNC_PROTOTYPES4#include <vmlinux.h>5#include <bpf/bpf_helpers.h>6#include <bpf/bpf_tracing.h>7#include <bpf/bpf_core_read.h>8#include "bpf_experimental.h"9 10struct {11 __uint(type, BPF_MAP_TYPE_ARENA);12 __uint(map_flags, BPF_F_MMAPABLE);13 __uint(max_entries, 100); /* number of pages */14} arena SEC(".maps");15 16#include "bpf_arena_htab.h"17 18void __arena *htab_for_user;19bool skip = false;20 21int zero = 0;22char __arena arr1[100000];23char arr2[1000];24 25SEC("syscall")26int arena_htab_llvm(void *ctx)27{28#if defined(__BPF_FEATURE_ADDR_SPACE_CAST) || defined(BPF_ARENA_FORCE_ASM)29 struct htab __arena *htab;30 char __arena *arr = arr1;31 __u64 i;32 33 htab = bpf_alloc(sizeof(*htab));34 cast_kern(htab);35 htab_init(htab);36 37 cast_kern(arr);38 39 /* first run. No old elems in the table */40 for (i = zero; i < 100000 && can_loop; i++) {41 htab_update_elem(htab, i, i);42 arr[i] = i;43 }44 45 /* should replace some elems with new ones */46 for (i = zero; i < 1000 && can_loop; i++) {47 htab_update_elem(htab, i, i);48 /* Access mem to make the verifier use bounded loop logic */49 arr2[i] = i;50 }51 cast_user(htab);52 htab_for_user = htab;53#else54 skip = true;55#endif56 return 0;57}58 59char _license[] SEC("license") = "GPL";60