// SPDX-License-Identifier: GPL-2.0 /* Copyright (c) 2022 Meta Platforms, Inc. and affiliates. */ #include "vmlinux.h" #include <bpf/bpf_helpers.h> #include "bpf_misc.h" #define HASHMAP_SZ 4194304 struct { __uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS); __uint(max_entries, 1000); __type(key, int); __type(value, int); __array(values, struct { __uint(type, BPF_MAP_TYPE_TASK_STORAGE); __uint(map_flags, BPF_F_NO_PREALLOC); __type(key, int); __type(value, int); }); } array_of_local_storage_maps SEC(".maps"); struct { __uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS); __uint(max_entries, 1000); __type(key, int); __type(value, int); __array(values, struct { __uint(type, BPF_MAP_TYPE_HASH); __uint(max_entries, HASHMAP_SZ); __type(key, int); __type(value, int); }); } array_of_hash_maps SEC(".maps"); long important_hits; long hits; /* set from user-space */ const volatile unsigned int use_hashmap; const volatile unsigned int hashmap_num_keys; const volatile unsigned int num_maps; const volatile unsigned int interleave; struct loop_ctx { struct task_struct *task; long loop_hits; long loop_important_hits; }; static int do_lookup(unsigned int elem, struct loop_ctx *lctx) { void *map, *inner_map; int idx = 0; if (use_hashmap) map = &array_of_hash_maps; else map = &array_of_local_storage_maps; inner_map = bpf_map_lookup_elem(map, &elem); if (!inner_map) return -1; if (use_hashmap) { idx = bpf_get_prandom_u32() % hashmap_num_keys; bpf_map_lookup_elem(inner_map, &idx); } else { bpf_task_storage_get(inner_map, lctx->task, &idx, BPF_LOCAL_STORAGE_GET_F_CREATE); } lctx->loop_hits++; if (!elem) lctx->loop_important_hits++; return 0; } static long loop(u32 index, void *ctx) { struct loop_ctx *lctx = (struct loop_ctx *)ctx; unsigned int map_idx = index % num_maps; do_lookup(map_idx, lctx); if (interleave && map_idx % 3 == 0) do_lookup(0, lctx); return 0; } SEC("fentry/" SYS_PREFIX "sys_getpgid") int get_local(void *ctx) { struct loop_ctx lctx; lctx.task = bpf_get_current_task_btf(); lctx.loop_hits = 0; lctx.loop_important_hits = 0; bpf_loop(10000, &loop, &lctx, 0); __sync_add_and_fetch(&hits, lctx.loop_hits); __sync_add_and_fetch(&important_hits, lctx.loop_important_hits); return 0; } char _license[] SEC("license") = "GPL";