github.com/bytedance/mockey@v1.2.10/internal/monkey/common/page.go (about) 1 /* 2 * Copyright 2022 ByteDance Inc. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package common 18 19 import ( 20 "syscall" 21 "unsafe" 22 ) 23 24 var pageSize = uintptr(syscall.Getpagesize()) 25 26 func PageOf(ptr uintptr) uintptr { 27 return ptr &^ (pageSize - 1) 28 } 29 30 func PageSize() int { 31 return int(pageSize) 32 } 33 34 func AllocatePage() []byte { 35 var memStats uint64 = 0 36 addr := sysAlloc(pageSize, &memStats) 37 return BytesOf(uintptr(addr), int(pageSize)) 38 } 39 40 func ReleasePage(mem []byte) { 41 memStats := uint64(cap(mem)) 42 sysFree(unsafe.Pointer(PtrOf(mem)), uintptr(cap(mem)), &memStats) 43 }