base.hh revision 12600:e670dd17c8cf
1/* 2 * Copyright (c) 2012-2014,2016-2017 ARM Limited 3 * All rights reserved. 4 * 5 * The license below extends only to copyright in the software and shall 6 * not be construed as granting a license to any other intellectual 7 * property including but not limited to intellectual property relating 8 * to a hardware implementation of the functionality of the software 9 * licensed hereunder. You may use the software subject to the license 10 * terms below provided that you ensure that this notice is replicated 11 * unmodified and in its entirety in all distributions of the software, 12 * modified or unmodified, in source code or in binary form. 13 * 14 * Copyright (c) 2003-2005 The Regents of The University of Michigan 15 * All rights reserved. 16 * 17 * Redistribution and use in source and binary forms, with or without 18 * modification, are permitted provided that the following conditions are 19 * met: redistributions of source code must retain the above copyright 20 * notice, this list of conditions and the following disclaimer; 21 * redistributions in binary form must reproduce the above copyright 22 * notice, this list of conditions and the following disclaimer in the 23 * documentation and/or other materials provided with the distribution; 24 * neither the name of the copyright holders nor the names of its 25 * contributors may be used to endorse or promote products derived from 26 * this software without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 31 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 32 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 38 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 39 * 40 * Authors: Erik Hallnor 41 * Ron Dreslinski 42 */ 43 44/** 45 * @file 46 * Declaration of a common base class for cache tagstore objects. 47 */ 48 49#ifndef __MEM_CACHE_TAGS_BASE_HH__ 50#define __MEM_CACHE_TAGS_BASE_HH__ 51 52#include <string> 53 54#include "base/callback.hh" 55#include "base/statistics.hh" 56#include "mem/cache/blk.hh" 57#include "mem/cache/replacement_policies/base.hh" 58#include "params/BaseTags.hh" 59#include "sim/clocked_object.hh" 60 61class BaseCache; 62 63/** 64 * A common base class of Cache tagstore objects. 65 */ 66class BaseTags : public ClockedObject 67{ 68 protected: 69 /** The block size of the cache. */ 70 const unsigned blkSize; 71 /** Mask out all bits that aren't part of the block offset. */ 72 const Addr blkMask; 73 /** The size of the cache. */ 74 const unsigned size; 75 /** The tag lookup latency of the cache. */ 76 const Cycles lookupLatency; 77 /** 78 * The total access latency of the cache. This latency 79 * is different depending on the cache access mode 80 * (parallel or sequential) 81 */ 82 const Cycles accessLatency; 83 /** Pointer to the parent cache. */ 84 BaseCache *cache; 85 86 /** 87 * The number of tags that need to be touched to meet the warmup 88 * percentage. 89 */ 90 const unsigned warmupBound; 91 /** Marked true when the cache is warmed up. */ 92 bool warmedUp; 93 94 /** the number of blocks in the cache */ 95 const unsigned numBlocks; 96 97 // Statistics 98 /** 99 * TODO: It would be good if these stats were acquired after warmup. 100 * @addtogroup CacheStatistics 101 * @{ 102 */ 103 104 /** Number of replacements of valid blocks per thread. */ 105 Stats::Vector replacements; 106 /** Per cycle average of the number of tags that hold valid data. */ 107 Stats::Average tagsInUse; 108 109 /** The total number of references to a block before it is replaced. */ 110 Stats::Scalar totalRefs; 111 112 /** 113 * The number of reference counts sampled. This is different from 114 * replacements because we sample all the valid blocks when the simulator 115 * exits. 116 */ 117 Stats::Scalar sampledRefs; 118 119 /** 120 * Average number of references to a block before is was replaced. 121 * @todo This should change to an average stat once we have them. 122 */ 123 Stats::Formula avgRefs; 124 125 /** The cycle that the warmup percentage was hit. 0 on failure. */ 126 Stats::Scalar warmupCycle; 127 128 /** Average occupancy of each requestor using the cache */ 129 Stats::AverageVector occupancies; 130 131 /** Average occ % of each requestor using the cache */ 132 Stats::Formula avgOccs; 133 134 /** Occupancy of each context/cpu using the cache */ 135 Stats::Vector occupanciesTaskId; 136 137 /** Occupancy of each context/cpu using the cache */ 138 Stats::Vector2d ageTaskId; 139 140 /** Occ % of each context/cpu using the cache */ 141 Stats::Formula percentOccsTaskId; 142 143 /** Number of tags consulted over all accesses. */ 144 Stats::Scalar tagAccesses; 145 /** Number of data blocks consulted over all accesses. */ 146 Stats::Scalar dataAccesses; 147 148 /** 149 * @} 150 */ 151 152 public: 153 typedef BaseTagsParams Params; 154 BaseTags(const Params *p); 155 156 /** 157 * Destructor. 158 */ 159 virtual ~BaseTags() {} 160 161 /** 162 * Set the parent cache back pointer. 163 * @param _cache Pointer to parent cache. 164 */ 165 void setCache(BaseCache *_cache); 166 167 /** 168 * Register local statistics. 169 */ 170 void regStats(); 171 172 /** 173 * Average in the reference count for valid blocks when the simulation 174 * exits. 175 */ 176 virtual void cleanupRefs() {} 177 178 /** 179 * Computes stats just prior to dump event 180 */ 181 virtual void computeStats() {} 182 183 /** 184 * Print all tags used 185 */ 186 virtual std::string print() const = 0; 187 188 /** 189 * Find a block using the memory address 190 */ 191 virtual CacheBlk * findBlock(Addr addr, bool is_secure) const = 0; 192 193 /** 194 * Align an address to the block size. 195 * @param addr the address to align. 196 * @return The block address. 197 */ 198 Addr blkAlign(Addr addr) const 199 { 200 return addr & ~blkMask; 201 } 202 203 /** 204 * Calculate the block offset of an address. 205 * @param addr the address to get the offset of. 206 * @return the block offset. 207 */ 208 int extractBlkOffset(Addr addr) const 209 { 210 return (addr & blkMask); 211 } 212 213 /** 214 * Find the cache block given set and way 215 * @param set The set of the block. 216 * @param way The way of the block. 217 * @return The cache block. 218 */ 219 virtual CacheBlk *findBlockBySetAndWay(int set, int way) const = 0; 220 221 /** 222 * Limit the allocation for the cache ways. 223 * @param ways The maximum number of ways available for replacement. 224 */ 225 virtual void setWayAllocationMax(int ways) 226 { 227 panic("This tag class does not implement way allocation limit!\n"); 228 } 229 230 /** 231 * Get the way allocation mask limit. 232 * @return The maximum number of ways available for replacement. 233 */ 234 virtual int getWayAllocationMax() const 235 { 236 panic("This tag class does not implement way allocation limit!\n"); 237 return -1; 238 } 239 240 /** 241 * This function updates the tags when a block is invalidated but 242 * does not invalidate the block itself. 243 * @param blk The block to invalidate. 244 */ 245 virtual void invalidate(CacheBlk *blk) 246 { 247 assert(blk); 248 assert(blk->isValid()); 249 tagsInUse--; 250 occupancies[blk->srcMasterId]--; 251 } 252 253 /** 254 * Find replacement victim based on address. 255 * 256 * @param addr Address to find a victim for. 257 * @return Cache block to be replaced. 258 */ 259 virtual CacheBlk* findVictim(Addr addr) = 0; 260 261 virtual CacheBlk* accessBlock(Addr addr, bool is_secure, Cycles &lat) = 0; 262 263 virtual Addr extractTag(Addr addr) const = 0; 264 265 virtual void insertBlock(PacketPtr pkt, CacheBlk *blk) = 0; 266 267 /** 268 * Regenerate the block address. 269 * 270 * @param block The block. 271 * @return the block address. 272 */ 273 virtual Addr regenerateBlkAddr(const CacheBlk* blk) const = 0; 274 275 virtual int extractSet(Addr addr) const = 0; 276 277 virtual void forEachBlk(CacheBlkVisitor &visitor) = 0; 278}; 279 280class BaseTagsCallback : public Callback 281{ 282 BaseTags *tags; 283 public: 284 BaseTagsCallback(BaseTags *t) : tags(t) {} 285 virtual void process() { tags->cleanupRefs(); }; 286}; 287 288class BaseTagsDumpCallback : public Callback 289{ 290 BaseTags *tags; 291 public: 292 BaseTagsDumpCallback(BaseTags *t) : tags(t) {} 293 virtual void process() { tags->computeStats(); }; 294}; 295 296#endif //__MEM_CACHE_TAGS_BASE_HH__ 297