base.hh revision 13223:081299f403fe
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/cache_blk.hh" 61#include "params/BaseTags.hh" 62#include "sim/clocked_object.hh" 63 64class BaseCache; 65class IndexingPolicy; 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 /** Indexing policy */ 92 BaseIndexingPolicy *indexingPolicy; 93 94 /** 95 * The number of tags that need to be touched to meet the warmup 96 * percentage. 97 */ 98 const unsigned warmupBound; 99 /** Marked true when the cache is warmed up. */ 100 bool warmedUp; 101 102 /** the number of blocks in the cache */ 103 const unsigned numBlocks; 104 105 /** The data blocks, 1 per cache block. */ 106 std::unique_ptr<uint8_t[]> dataBlks; 107 108 // Statistics 109 /** 110 * TODO: It would be good if these stats were acquired after warmup. 111 * @addtogroup CacheStatistics 112 * @{ 113 */ 114 115 /** Per cycle average of the number of tags that hold valid data. */ 116 Stats::Average tagsInUse; 117 118 /** The total number of references to a block before it is replaced. */ 119 Stats::Scalar totalRefs; 120 121 /** 122 * The number of reference counts sampled. This is different from 123 * replacements because we sample all the valid blocks when the simulator 124 * exits. 125 */ 126 Stats::Scalar sampledRefs; 127 128 /** 129 * Average number of references to a block before is was replaced. 130 * @todo This should change to an average stat once we have them. 131 */ 132 Stats::Formula avgRefs; 133 134 /** The cycle that the warmup percentage was hit. 0 on failure. */ 135 Stats::Scalar warmupCycle; 136 137 /** Average occupancy of each requestor using the cache */ 138 Stats::AverageVector occupancies; 139 140 /** Average occ % of each requestor using the cache */ 141 Stats::Formula avgOccs; 142 143 /** Occupancy of each context/cpu using the cache */ 144 Stats::Vector occupanciesTaskId; 145 146 /** Occupancy of each context/cpu using the cache */ 147 Stats::Vector2d ageTaskId; 148 149 /** Occ % of each context/cpu using the cache */ 150 Stats::Formula percentOccsTaskId; 151 152 /** Number of tags consulted over all accesses. */ 153 Stats::Scalar tagAccesses; 154 /** Number of data blocks consulted over all accesses. */ 155 Stats::Scalar dataAccesses; 156 157 /** 158 * @} 159 */ 160 161 /** 162 * Set the parent cache back pointer. 163 * 164 * @param _cache Pointer to parent cache. 165 */ 166 void setCache(BaseCache *_cache); 167 168 public: 169 typedef BaseTagsParams Params; 170 BaseTags(const Params *p); 171 172 /** 173 * Destructor. 174 */ 175 virtual ~BaseTags() {} 176 177 /** 178 * Initialize blocks and set the parent cache back pointer. 179 * 180 * @param _cache Pointer to parent cache. 181 */ 182 virtual void init(BaseCache *_cache) = 0; 183 184 /** 185 * Register local statistics. 186 */ 187 void regStats(); 188 189 /** 190 * Average in the reference count for valid blocks when the simulation 191 * exits. 192 */ 193 void cleanupRefs(); 194 195 /** 196 * Computes stats just prior to dump event 197 */ 198 void computeStats(); 199 200 /** 201 * Print all tags used 202 */ 203 std::string print(); 204 205 /** 206 * Finds the block in the cache without touching it. 207 * 208 * @param addr The address to look for. 209 * @param is_secure True if the target memory space is secure. 210 * @return Pointer to the cache block. 211 */ 212 virtual CacheBlk *findBlock(Addr addr, bool is_secure) const; 213 214 /** 215 * Find a block given set and way. 216 * 217 * @param set The set of the block. 218 * @param way The way of the block. 219 * @return The block. 220 */ 221 virtual ReplaceableEntry* findBlockBySetAndWay(int set, int way) const; 222 223 /** 224 * Align an address to the block size. 225 * @param addr the address to align. 226 * @return The block address. 227 */ 228 Addr blkAlign(Addr addr) const 229 { 230 return addr & ~blkMask; 231 } 232 233 /** 234 * Calculate the block offset of an address. 235 * @param addr the address to get the offset of. 236 * @return the block offset. 237 */ 238 int extractBlkOffset(Addr addr) const 239 { 240 return (addr & blkMask); 241 } 242 243 /** 244 * Limit the allocation for the cache ways. 245 * @param ways The maximum number of ways available for replacement. 246 */ 247 virtual void setWayAllocationMax(int ways) 248 { 249 panic("This tag class does not implement way allocation limit!\n"); 250 } 251 252 /** 253 * Get the way allocation mask limit. 254 * @return The maximum number of ways available for replacement. 255 */ 256 virtual int getWayAllocationMax() const 257 { 258 panic("This tag class does not implement way allocation limit!\n"); 259 return -1; 260 } 261 262 /** 263 * This function updates the tags when a block is invalidated 264 * 265 * @param blk A valid block to invalidate. 266 */ 267 virtual void invalidate(CacheBlk *blk) 268 { 269 assert(blk); 270 assert(blk->isValid()); 271 272 occupancies[blk->srcMasterId]--; 273 totalRefs += blk->refCount; 274 sampledRefs++; 275 276 blk->invalidate(); 277 } 278 279 /** 280 * Find replacement victim based on address. If the address requires 281 * blocks to be evicted, their locations are listed for eviction. If a 282 * conventional cache is being used, the list only contains the victim. 283 * However, if using sector or compressed caches, the victim is one of 284 * the blocks to be evicted, but its location is the only one that will 285 * be assigned to the newly allocated block associated to this address. 286 * @sa insertBlock 287 * 288 * @param addr Address to find a victim for. 289 * @param is_secure True if the target memory space is secure. 290 * @param evict_blks Cache blocks to be evicted. 291 * @return Cache block to be replaced. 292 */ 293 virtual CacheBlk* findVictim(Addr addr, const bool is_secure, 294 std::vector<CacheBlk*>& evict_blks) const = 0; 295 296 virtual CacheBlk* accessBlock(Addr addr, bool is_secure, Cycles &lat) = 0; 297 298 /** 299 * Generate the tag from the given address. 300 * 301 * @param addr The address to get the tag from. 302 * @return The tag of the address. 303 */ 304 virtual Addr extractTag(const Addr addr) const; 305 306 /** 307 * Insert the new block into the cache and update stats. 308 * 309 * @param addr Address of the block. 310 * @param is_secure Whether the block is in secure space or not. 311 * @param src_master_ID The source requestor ID. 312 * @param task_ID The new task ID. 313 * @param blk The block to update. 314 */ 315 virtual void insertBlock(const Addr addr, const bool is_secure, 316 const int src_master_ID, const uint32_t task_ID, 317 CacheBlk *blk); 318 319 /** 320 * Regenerate the block address. 321 * 322 * @param block The block. 323 * @return the block address. 324 */ 325 virtual Addr regenerateBlkAddr(const CacheBlk* blk) const = 0; 326 327 /** 328 * Visit each block in the tags and apply a visitor 329 * 330 * The visitor should be a std::function that takes a cache block 331 * reference as its parameter. 332 * 333 * @param visitor Visitor to call on each block. 334 */ 335 virtual void forEachBlk(std::function<void(CacheBlk &)> visitor) = 0; 336 337 /** 338 * Find if any of the blocks satisfies a condition 339 * 340 * The visitor should be a std::function that takes a cache block 341 * reference as its parameter. The visitor will terminate the 342 * traversal early if the condition is satisfied. 343 * 344 * @param visitor Visitor to call on each block. 345 */ 346 virtual bool anyBlk(std::function<bool(CacheBlk &)> visitor) = 0; 347 348 private: 349 /** 350 * Update the reference stats using data from the input block 351 * 352 * @param blk The input block 353 */ 354 void cleanupRefsVisitor(CacheBlk &blk); 355 356 /** 357 * Update the occupancy and age stats using data from the input block 358 * 359 * @param blk The input block 360 */ 361 void computeStatsVisitor(CacheBlk &blk); 362}; 363 364class BaseTagsCallback : public Callback 365{ 366 BaseTags *tags; 367 public: 368 BaseTagsCallback(BaseTags *t) : tags(t) {} 369 virtual void process() { tags->cleanupRefs(); }; 370}; 371 372class BaseTagsDumpCallback : public Callback 373{ 374 BaseTags *tags; 375 public: 376 BaseTagsDumpCallback(BaseTags *t) : tags(t) {} 377 virtual void process() { tags->computeStats(); }; 378}; 379 380#endif //__MEM_CACHE_TAGS_BASE_HH__ 381