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basil
2026-04-14 21:30:38 +08:00
parent 785e92ec8b
commit 2c61ef07ff
172 changed files with 202485 additions and 68 deletions
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Assets/Scripts/Simulation/AddressGenerator.cs
+61 -7
View File
@@ -1,4 +1,5 @@
using System;
using VMdemo.Core;
namespace VMdemo.Simulation
{
@@ -6,28 +7,74 @@ namespace VMdemo.Simulation
{
public const int DefaultSeed = 12345;
private readonly int _vaBits;
private readonly ulong _vaMask;
private readonly Random _random;
private readonly byte[] _buffer = new byte[8];
private readonly AddressGenerationMode _mode;
private readonly ulong _arrayBaseAddress;
private readonly ulong _arrayElementBytes;
private readonly ulong _arrayElementCount;
private ulong _nextArrayIndex;
public AddressGenerator(int vaBits, int? seed = null)
public AddressGenerator(
int vaBits,
int? seed = null,
AddressGenerationMode mode = AddressGenerationMode.RandomUniform,
int arrayLengthBytes = 256,
int arrayElementBytes = 4,
int arrayBaseAddress = 0)
{
if (vaBits != 32 && vaBits != 48 && vaBits != 64)
if (vaBits != 8 && vaBits != 16 && vaBits != 24)
{
throw new ArgumentOutOfRangeException(nameof(vaBits), "vaBits 仅支持 32、48、64。");
throw new ArgumentOutOfRangeException(nameof(vaBits), "vaBits 仅支持 8、16、24。");
}
_vaBits = vaBits;
_vaMask = vaBits == 64 ? ulong.MaxValue : (1UL << vaBits) - 1UL;
_vaMask = (1UL << vaBits) - 1UL;
_random = new Random(seed ?? DefaultSeed);
_mode = mode;
if (arrayLengthBytes <= 0)
{
throw new ArgumentOutOfRangeException(nameof(arrayLengthBytes), "arrayLengthBytes 必须是正整数。");
}
if (arrayElementBytes <= 0)
{
throw new ArgumentOutOfRangeException(nameof(arrayElementBytes), "arrayElementBytes 必须是正整数。");
}
if (arrayBaseAddress < 0)
{
throw new ArgumentOutOfRangeException(nameof(arrayBaseAddress), "arrayBaseAddress 不能为负数。");
}
if (mode == AddressGenerationMode.SequentialArrayLoop && arrayLengthBytes < arrayElementBytes)
{
throw new ArgumentOutOfRangeException(
nameof(arrayLengthBytes),
"SequentialArrayLoop 模式下 arrayLengthBytes 必须 >= arrayElementBytes。");
}
_arrayBaseAddress = (ulong)arrayBaseAddress;
_arrayElementBytes = (ulong)arrayElementBytes;
_arrayElementCount = Math.Max(1UL, (ulong)arrayLengthBytes / _arrayElementBytes);
var maxGenerated = _arrayBaseAddress + (_arrayElementCount - 1UL) * _arrayElementBytes;
if (maxGenerated > _vaMask)
{
throw new ArgumentOutOfRangeException(
nameof(arrayLengthBytes),
$"数组访问地址超出 vaBits 范围。maxGenerated={maxGenerated}, maxVA={_vaMask}");
}
}
public ulong MaxVirtualAddress => _vaMask;
public ulong NextVirtualAddress()
{
return NextRawUlong() & _vaMask;
return _mode == AddressGenerationMode.SequentialArrayLoop
? NextArrayLoopAddress()
: (NextRawUlong() & _vaMask);
}
private ulong NextRawUlong()
@@ -35,5 +82,12 @@ namespace VMdemo.Simulation
_random.NextBytes(_buffer);
return BitConverter.ToUInt64(_buffer, 0);
}
private ulong NextArrayLoopAddress()
{
var address = _arrayBaseAddress + _nextArrayIndex * _arrayElementBytes;
_nextArrayIndex = (_nextArrayIndex + 1UL) % _arrayElementCount;
return address;
}
}
}
Assets/Scripts/Simulation/SimulationState.cs
+2
View File
@@ -17,6 +17,7 @@ namespace VMdemo.Simulation
public bool IsTlbHit { get; set; }
public bool IsPageTableHit { get; set; }
public int CurrentCost { get; set; }
public string LastDecisionReason { get; set; }
public void Reset()
{
@@ -31,6 +32,7 @@ namespace VMdemo.Simulation
IsTlbHit = false;
IsPageTableHit = false;
CurrentCost = 0;
LastDecisionReason = string.Empty;
}
}
}
Assets/Scripts/Simulation/TranslatorEngine.cs
+50 -9
View File
@@ -81,7 +81,7 @@ namespace VMdemo.Simulation
L1Bits = l1Bits;
L2Bits = l2Bits;
_addressGenerator = new AddressGenerator(_config.vaBits, _seed);
_addressGenerator = CreateAddressGenerator();
_tlbCache = new TlbCache(_config.tlbEntries);
_pageTable = new TwoLevelPageTable(L1Bits, L2Bits);
_physicalMemoryManager = new PhysicalMemoryManager(_derivedConfig.FrameCount);
@@ -91,6 +91,10 @@ namespace VMdemo.Simulation
public SimulationState State { get; }
public TranslationStep CurrentStep => State.CurrentStep;
public int MachineBits => _config.machineBits;
public int VaBits => _config.vaBits;
public int PageSizeKB => _config.pageSizeKB;
public int PhysicalMemoryMB => _config.physicalMemoryMB;
public int OffsetBits => _derivedConfig.OffsetBits;
public int L1Bits { get; }
public int L2Bits { get; }
@@ -109,7 +113,7 @@ namespace VMdemo.Simulation
_pendingForcedVirtualAddress = 0UL;
Stats.Reset();
_addressGenerator = new AddressGenerator(_config.vaBits, _seed);
_addressGenerator = CreateAddressGenerator();
_tlbCache = new TlbCache(_config.tlbEntries);
_pageTable = new TwoLevelPageTable(L1Bits, L2Bits);
_physicalMemoryManager = new PhysicalMemoryManager(_derivedConfig.FrameCount);
@@ -190,6 +194,7 @@ namespace VMdemo.Simulation
State.CurrentPhysicalAddress = 0UL;
State.CurrentPfn = 0UL;
State.HasCurrentPfn = false;
State.LastDecisionReason = "已生成本轮虚拟地址，准备进行地址拆分。";
_lastEviction = EvictionInfo.None;
if (_hasPendingForcedVirtualAddress)
@@ -212,6 +217,7 @@ namespace VMdemo.Simulation
State.CurrentVirtualAddress,
_config.vaBits,
_derivedConfig.OffsetBits);
State.LastDecisionReason = "已拆分 VA 为 VPN/Offset，并从 VPN 拆分出 L1/L2 索引。";
State.CurrentStep = TranslationStep.LookupTLB;
}
@@ -223,28 +229,42 @@ namespace VMdemo.Simulation
State.IsTlbHit = true;
State.CurrentPfn = pfn;
State.HasCurrentPfn = true;
State.LastDecisionReason =
$"TLB 命中：VPN={State.CurrentAddressParts.Vpn} 命中 PFN={pfn}，跳过页表，直接合成物理地址。";
State.CurrentStep = TranslationStep.ComposePA;
return;
}
State.LastDecisionReason =
$"TLB 未命中：VPN={State.CurrentAddressParts.Vpn} 未找到映射，转入页表查询。";
State.CurrentStep = TranslationStep.LookupPageTable;
}
private void ExecuteLookupPageTable()
{
if (_pageTable.TryGetPresentPfn(
State.CurrentAddressParts.L1Index,
State.CurrentAddressParts.L2Index,
out var pfn))
var probe = _pageTable.Probe(State.CurrentAddressParts.L1Index, State.CurrentAddressParts.L2Index);
if (probe.Status == PageTableProbeStatus.PresentEntry)
{
State.IsPageTableHit = true;
State.CurrentPfn = pfn;
State.CurrentPfn = probe.Entry.Pfn;
State.HasCurrentPfn = true;
_tlbCache.InsertOrUpdate(State.CurrentAddressParts.Vpn, pfn);
_tlbCache.InsertOrUpdate(State.CurrentAddressParts.Vpn, probe.Entry.Pfn);
State.LastDecisionReason =
$"页表命中：L1={State.CurrentAddressParts.L1Index}, L2={State.CurrentAddressParts.L2Index}, PFN={probe.Entry.Pfn}，并写回 TLB。";
State.CurrentStep = TranslationStep.ComposePA;
return;
}
State.LastDecisionReason = probe.Status switch
{
PageTableProbeStatus.MissingL1Table =>
$"页表未命中：L1={State.CurrentAddressParts.L1Index} 对应二级页表不存在，触发缺页处理。",
PageTableProbeStatus.MissingL2Entry =>
$"页表未命中：L2={State.CurrentAddressParts.L2Index} 页表项不存在，触发缺页处理。",
PageTableProbeStatus.NotPresentEntry =>
$"页表项无效：L2={State.CurrentAddressParts.L2Index} present=false，触发缺页处理。",
_ => "页表未命中，触发缺页处理。"
};
State.CurrentStep = TranslationStep.HandlePageFault;
}
@@ -263,6 +283,9 @@ namespace VMdemo.Simulation
State.CurrentPfn = result.Pfn;
State.HasCurrentPfn = true;
_lastEviction = result.Eviction;
State.LastDecisionReason = result.Eviction.HasEvicted
? $"缺页处理完成：装入 PFN={result.Pfn}，并按 FIFO 淘汰 VPN={result.Eviction.EvictedVpn}。"
: $"缺页处理完成：装入 PFN={result.Pfn}，当前仍有空闲物理帧。";
State.CurrentStep = TranslationStep.ComposePA;
}
@@ -275,6 +298,8 @@ namespace VMdemo.Simulation
State.CurrentPhysicalAddress =
(State.CurrentPfn << _derivedConfig.OffsetBits) | State.CurrentAddressParts.Offset;
State.LastDecisionReason =
$"物理地址合成：PA = (PFN << offsetBits) | offset = ({State.CurrentPfn} << {_derivedConfig.OffsetBits}) | {State.CurrentAddressParts.Offset}。";
State.CurrentStep = TranslationStep.Finalize;
}
@@ -291,6 +316,11 @@ namespace VMdemo.Simulation
State.IsPageTableHit,
State.IsPageFault,
State.CurrentCost);
State.LastDecisionReason = State.IsPageFault
? $"本轮完成：TLB 未命中 + 页表未命中，发生缺页，开销={State.CurrentCost}。"
: State.IsTlbHit
? $"本轮完成：TLB 命中，开销={State.CurrentCost}。"
: $"本轮完成：TLB 未命中 + 页表命中，开销={State.CurrentCost}。";
State.CurrentRound += 1;
State.CurrentStep = TranslationStep.GenerateVA;
@@ -298,10 +328,21 @@ namespace VMdemo.Simulation
private void EnsureVirtualAddressInRange(ulong virtualAddress)
{
if (_config.vaBits < 64 && virtualAddress > _addressGenerator.MaxVirtualAddress)
if (virtualAddress > _addressGenerator.MaxVirtualAddress)
{
throw new ArgumentOutOfRangeException(nameof(virtualAddress), "virtualAddress 超出 vaBits 可表示范围。");
}
}
private AddressGenerator CreateAddressGenerator()
{
return new AddressGenerator(
_config.vaBits,
_seed,
_config.addressGenerationMode,
_config.arrayLengthBytes,
_config.arrayElementBytes,
_config.arrayBaseAddress);
}
}
}
Assets/Scripts/Simulation/TwoLevelPageTable.cs
+56
View File
@@ -3,6 +3,28 @@ using System.Collections.Generic;
namespace VMdemo.Simulation
{
public enum PageTableProbeStatus
{
MissingL1Table = 0,
MissingL2Entry = 1,
NotPresentEntry = 2,
PresentEntry = 3
}
public readonly struct PageTableProbeResult
{
public PageTableProbeResult(PageTableProbeStatus status, bool hasEntry, PageTableEntry entry)
{
Status = status;
HasEntry = hasEntry;
Entry = entry;
}
public PageTableProbeStatus Status { get; }
public bool HasEntry { get; }
public PageTableEntry Entry { get; }
}
public class TwoLevelPageTable
{
private readonly Dictionary<ulong, Dictionary<ulong, PageTableEntry>> _table;
@@ -73,6 +95,40 @@ namespace VMdemo.Simulation
return false;
}
public PageTableProbeResult Probe(ulong l1Index, ulong l2Index)
{
ValidateIndices(l1Index, l2Index);
if (!_table.TryGetValue(l1Index, out var l2Table))
{
return new PageTableProbeResult(
PageTableProbeStatus.MissingL1Table,
hasEntry: false,
entry: PageTableEntry.NotPresent);
}
if (!l2Table.TryGetValue(l2Index, out var entry))
{
return new PageTableProbeResult(
PageTableProbeStatus.MissingL2Entry,
hasEntry: false,
entry: PageTableEntry.NotPresent);
}
if (!entry.Present)
{
return new PageTableProbeResult(
PageTableProbeStatus.NotPresentEntry,
hasEntry: true,
entry: entry);
}
return new PageTableProbeResult(
PageTableProbeStatus.PresentEntry,
hasEntry: true,
entry: entry);
}
public void SetPresent(ulong l1Index, ulong l2Index, ulong pfn, bool dirty = false)
{
ValidateIndices(l1Index, l2Index);