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1// SPDX-License-Identifier: GPL-2.02/* Copyright (c) 2022 Meta Platforms, Inc. and affiliates. */3 4#include "vmlinux.h"5#include <bpf/bpf_helpers.h>6#include "bpf_misc.h"7 8#define HASHMAP_SZ 41943049 10struct {11 __uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS);12 __uint(max_entries, 1000);13 __type(key, int);14 __type(value, int);15 __array(values, struct {16 __uint(type, BPF_MAP_TYPE_TASK_STORAGE);17 __uint(map_flags, BPF_F_NO_PREALLOC);18 __type(key, int);19 __type(value, int);20 });21} array_of_local_storage_maps SEC(".maps");22 23struct {24 __uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS);25 __uint(max_entries, 1000);26 __type(key, int);27 __type(value, int);28 __array(values, struct {29 __uint(type, BPF_MAP_TYPE_HASH);30 __uint(max_entries, HASHMAP_SZ);31 __type(key, int);32 __type(value, int);33 });34} array_of_hash_maps SEC(".maps");35 36long important_hits;37long hits;38 39/* set from user-space */40const volatile unsigned int use_hashmap;41const volatile unsigned int hashmap_num_keys;42const volatile unsigned int num_maps;43const volatile unsigned int interleave;44 45struct loop_ctx {46 struct task_struct *task;47 long loop_hits;48 long loop_important_hits;49};50 51static int do_lookup(unsigned int elem, struct loop_ctx *lctx)52{53 void *map, *inner_map;54 int idx = 0;55 56 if (use_hashmap)57 map = &array_of_hash_maps;58 else59 map = &array_of_local_storage_maps;60 61 inner_map = bpf_map_lookup_elem(map, &elem);62 if (!inner_map)63 return -1;64 65 if (use_hashmap) {66 idx = bpf_get_prandom_u32() % hashmap_num_keys;67 bpf_map_lookup_elem(inner_map, &idx);68 } else {69 bpf_task_storage_get(inner_map, lctx->task, &idx,70 BPF_LOCAL_STORAGE_GET_F_CREATE);71 }72 73 lctx->loop_hits++;74 if (!elem)75 lctx->loop_important_hits++;76 return 0;77}78 79static long loop(u32 index, void *ctx)80{81 struct loop_ctx *lctx = (struct loop_ctx *)ctx;82 unsigned int map_idx = index % num_maps;83 84 do_lookup(map_idx, lctx);85 if (interleave && map_idx % 3 == 0)86 do_lookup(0, lctx);87 return 0;88}89 90SEC("fentry/" SYS_PREFIX "sys_getpgid")91int get_local(void *ctx)92{93 struct loop_ctx lctx;94 95 lctx.task = bpf_get_current_task_btf();96 lctx.loop_hits = 0;97 lctx.loop_important_hits = 0;98 bpf_loop(10000, &loop, &lctx, 0);99 __sync_add_and_fetch(&hits, lctx.loop_hits);100 __sync_add_and_fetch(&important_hits, lctx.loop_important_hits);101 return 0;102}103 104char _license[] SEC("license") = "GPL";105