base.hh revision 12773:387fa9e5c9ff
1/* 2 * Copyright (c) 2012-2014,2016-2018 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 <cassert> 53#include <functional> 54#include <string> 55 56#include "base/callback.hh" 57#include "base/logging.hh" 58#include "base/statistics.hh" 59#include "base/types.hh" 60#include "mem/cache/blk.hh" 61#include "mem/packet.hh" 62#include "params/BaseTags.hh" 63#include "sim/clocked_object.hh" 64 65class BaseCache; 66class ReplaceableEntry; 67 68/** 69 * A common base class of Cache tagstore objects. 70 */ 71class BaseTags : public ClockedObject 72{ 73 protected: 74 /** The block size of the cache. */ 75 const unsigned blkSize; 76 /** Mask out all bits that aren't part of the block offset. */ 77 const Addr blkMask; 78 /** The size of the cache. */ 79 const unsigned size; 80 /** The tag lookup latency of the cache. */ 81 const Cycles lookupLatency; 82 /** 83 * The total access latency of the cache. This latency 84 * is different depending on the cache access mode 85 * (parallel or sequential) 86 */ 87 const Cycles accessLatency; 88 /** Pointer to the parent cache. */ 89 BaseCache *cache; 90 91 /** 92 * The number of tags that need to be touched to meet the warmup 93 * percentage. 94 */ 95 const unsigned warmupBound; 96 /** Marked true when the cache is warmed up. */ 97 bool warmedUp; 98 99 /** the number of blocks in the cache */ 100 const unsigned numBlocks; 101 102 /** The data blocks, 1 per cache block. */ 103 std::unique_ptr<uint8_t[]> dataBlks; 104 105 // Statistics 106 /** 107 * TODO: It would be good if these stats were acquired after warmup. 108 * @addtogroup CacheStatistics 109 * @{ 110 */ 111 112 /** Per cycle average of the number of tags that hold valid data. */ 113 Stats::Average tagsInUse; 114 115 /** The total number of references to a block before it is replaced. */ 116 Stats::Scalar totalRefs; 117 118 /** 119 * The number of reference counts sampled. This is different from 120 * replacements because we sample all the valid blocks when the simulator 121 * exits. 122 */ 123 Stats::Scalar sampledRefs; 124 125 /** 126 * Average number of references to a block before is was replaced. 127 * @todo This should change to an average stat once we have them. 128 */ 129 Stats::Formula avgRefs; 130 131 /** The cycle that the warmup percentage was hit. 0 on failure. */ 132 Stats::Scalar warmupCycle; 133 134 /** Average occupancy of each requestor using the cache */ 135 Stats::AverageVector occupancies; 136 137 /** Average occ % of each requestor using the cache */ 138 Stats::Formula avgOccs; 139 140 /** Occupancy of each context/cpu using the cache */ 141 Stats::Vector occupanciesTaskId; 142 143 /** Occupancy of each context/cpu using the cache */ 144 Stats::Vector2d ageTaskId; 145 146 /** Occ % of each context/cpu using the cache */ 147 Stats::Formula percentOccsTaskId; 148 149 /** Number of tags consulted over all accesses. */ 150 Stats::Scalar tagAccesses; 151 /** Number of data blocks consulted over all accesses. */ 152 Stats::Scalar dataAccesses; 153 154 /** 155 * @} 156 */ 157 158 public: 159 typedef BaseTagsParams Params; 160 BaseTags(const Params *p); 161 162 /** 163 * Destructor. 164 */ 165 virtual ~BaseTags() {} 166 167 /** 168 * Set the parent cache back pointer. 169 * @param _cache Pointer to parent cache. 170 */ 171 void setCache(BaseCache *_cache); 172 173 /** 174 * Register local statistics. 175 */ 176 void regStats(); 177 178 /** 179 * Average in the reference count for valid blocks when the simulation 180 * exits. 181 */ 182 void cleanupRefs(); 183 184 /** 185 * Computes stats just prior to dump event 186 */ 187 void computeStats(); 188 189 /** 190 * Print all tags used 191 */ 192 std::string print(); 193 194 /** 195 * Find a block using the memory address 196 */ 197 virtual CacheBlk * findBlock(Addr addr, bool is_secure) const = 0; 198 199 /** 200 * Find a block given set and way. 201 * 202 * @param set The set of the block. 203 * @param way The way of the block. 204 * @return The block. 205 */ 206 virtual ReplaceableEntry* findBlockBySetAndWay(int set, int way) const = 0; 207 208 /** 209 * Align an address to the block size. 210 * @param addr the address to align. 211 * @return The block address. 212 */ 213 Addr blkAlign(Addr addr) const 214 { 215 return addr & ~blkMask; 216 } 217 218 /** 219 * Calculate the block offset of an address. 220 * @param addr the address to get the offset of. 221 * @return the block offset. 222 */ 223 int extractBlkOffset(Addr addr) const 224 { 225 return (addr & blkMask); 226 } 227 228 /** 229 * Limit the allocation for the cache ways. 230 * @param ways The maximum number of ways available for replacement. 231 */ 232 virtual void setWayAllocationMax(int ways) 233 { 234 panic("This tag class does not implement way allocation limit!\n"); 235 } 236 237 /** 238 * Get the way allocation mask limit. 239 * @return The maximum number of ways available for replacement. 240 */ 241 virtual int getWayAllocationMax() const 242 { 243 panic("This tag class does not implement way allocation limit!\n"); 244 return -1; 245 } 246 247 /** 248 * This function updates the tags when a block is invalidated 249 * 250 * @param blk A valid block to invalidate. 251 */ 252 virtual void invalidate(CacheBlk *blk) 253 { 254 assert(blk); 255 assert(blk->isValid()); 256 257 occupancies[blk->srcMasterId]--; 258 totalRefs += blk->refCount; 259 sampledRefs++; 260 261 blk->invalidate(); 262 } 263 264 /** 265 * Find replacement victim based on address. If the address requires 266 * blocks to be evicted, their locations are listed for eviction. If a 267 * conventional cache is being used, the list only contains the victim. 268 * However, if using sector or compressed caches, the victim is one of 269 * the blocks to be evicted, but its location is the only one that will 270 * be assigned to the newly allocated block associated to this address. 271 * @sa insertBlock 272 * 273 * @param addr Address to find a victim for. 274 * @param is_secure True if the target memory space is secure. 275 * @param evict_blks Cache blocks to be evicted. 276 * @return Cache block to be replaced. 277 */ 278 virtual CacheBlk* findVictim(Addr addr, const bool is_secure, 279 std::vector<CacheBlk*>& evict_blks) const = 0; 280 281 virtual CacheBlk* accessBlock(Addr addr, bool is_secure, Cycles &lat) = 0; 282 283 virtual Addr extractTag(Addr addr) const = 0; 284 285 /** 286 * Insert the new block into the cache and update stats. 287 * 288 * @param pkt Packet holding the address to update 289 * @param blk The block to update. 290 */ 291 virtual void insertBlock(const PacketPtr pkt, CacheBlk *blk); 292 293 /** 294 * Regenerate the block address. 295 * 296 * @param block The block. 297 * @return the block address. 298 */ 299 virtual Addr regenerateBlkAddr(const CacheBlk* blk) const = 0; 300 301 /** 302 * Visit each block in the tags and apply a visitor 303 * 304 * The visitor should be a std::function that takes a cache block 305 * reference as its parameter. 306 * 307 * @param visitor Visitor to call on each block. 308 */ 309 virtual void forEachBlk(std::function<void(CacheBlk &)> visitor) = 0; 310 311 /** 312 * Find if any of the blocks satisfies a condition 313 * 314 * The visitor should be a std::function that takes a cache block 315 * reference as its parameter. The visitor will terminate the 316 * traversal early if the condition is satisfied. 317 * 318 * @param visitor Visitor to call on each block. 319 */ 320 virtual bool anyBlk(std::function<bool(CacheBlk &)> visitor) = 0; 321 322 private: 323 /** 324 * Update the reference stats using data from the input block 325 * 326 * @param blk The input block 327 */ 328 void cleanupRefsVisitor(CacheBlk &blk); 329 330 /** 331 * Update the occupancy and age stats using data from the input block 332 * 333 * @param blk The input block 334 */ 335 void computeStatsVisitor(CacheBlk &blk); 336}; 337 338class BaseTagsCallback : public Callback 339{ 340 BaseTags *tags; 341 public: 342 BaseTagsCallback(BaseTags *t) : tags(t) {} 343 virtual void process() { tags->cleanupRefs(); }; 344}; 345 346class BaseTagsDumpCallback : public Callback 347{ 348 BaseTags *tags; 349 public: 350 BaseTagsDumpCallback(BaseTags *t) : tags(t) {} 351 virtual void process() { tags->computeStats(); }; 352}; 353 354#endif //__MEM_CACHE_TAGS_BASE_HH__ 355