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1// SPDX-License-Identifier: GPL-2.02/* Copyright (c) 2022 Bytedance */3 4#include "vmlinux.h"5#include <bpf/bpf_helpers.h>6 7__u64 percpu_array_elem_sum = 0;8__u64 percpu_hash_elem_sum = 0;9__u64 percpu_lru_hash_elem_sum = 0;10const volatile int nr_cpus;11const volatile int my_pid;12 13struct {14 __uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);15 __uint(max_entries, 1);16 __type(key, __u32);17 __type(value, __u64);18} percpu_array_map SEC(".maps");19 20struct {21 __uint(type, BPF_MAP_TYPE_PERCPU_HASH);22 __uint(max_entries, 1);23 __type(key, __u64);24 __type(value, __u64);25} percpu_hash_map SEC(".maps");26 27struct {28 __uint(type, BPF_MAP_TYPE_LRU_PERCPU_HASH);29 __uint(max_entries, 1);30 __type(key, __u64);31 __type(value, __u64);32} percpu_lru_hash_map SEC(".maps");33 34struct read_percpu_elem_ctx {35 void *map;36 __u64 sum;37};38 39static int read_percpu_elem_callback(__u32 index, struct read_percpu_elem_ctx *ctx)40{41 __u64 key = 0;42 __u64 *value;43 44 value = bpf_map_lookup_percpu_elem(ctx->map, &key, index);45 if (value)46 ctx->sum += *value;47 return 0;48}49 50SEC("tp/syscalls/sys_enter_getuid")51int sysenter_getuid(const void *ctx)52{53 struct read_percpu_elem_ctx map_ctx;54 55 if (my_pid != (bpf_get_current_pid_tgid() >> 32))56 return 0;57 58 map_ctx.map = &percpu_array_map;59 map_ctx.sum = 0;60 bpf_loop(nr_cpus, read_percpu_elem_callback, &map_ctx, 0);61 percpu_array_elem_sum = map_ctx.sum;62 63 map_ctx.map = &percpu_hash_map;64 map_ctx.sum = 0;65 bpf_loop(nr_cpus, read_percpu_elem_callback, &map_ctx, 0);66 percpu_hash_elem_sum = map_ctx.sum;67 68 map_ctx.map = &percpu_lru_hash_map;69 map_ctx.sum = 0;70 bpf_loop(nr_cpus, read_percpu_elem_callback, &map_ctx, 0);71 percpu_lru_hash_elem_sum = map_ctx.sum;72 73 return 0;74}75 76char _license[] SEC("license") = "GPL";77