base.hh revision 12566
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 "params/BaseTags.hh" 58#include "sim/clocked_object.hh" 59 60class BaseCache; 61 62/** 63 * A common base class of Cache tagstore objects. 64 */ 65class BaseTags : public ClockedObject 66{ 67 protected: 68 /** The block size of the cache. */ 69 const unsigned blkSize; 70 /** Mask out all bits that aren't part of the block offset. */ 71 const Addr blkMask; 72 /** The size of the cache. */ 73 const unsigned size; 74 /** The tag lookup latency of the cache. */ 75 const Cycles lookupLatency; 76 /** 77 * The total access latency of the cache. This latency 78 * is different depending on the cache access mode 79 * (parallel or sequential) 80 */ 81 const Cycles accessLatency; 82 /** Pointer to the parent cache. */ 83 BaseCache *cache; 84 85 /** 86 * The number of tags that need to be touched to meet the warmup 87 * percentage. 88 */ 89 const unsigned warmupBound; 90 /** Marked true when the cache is warmed up. */ 91 bool warmedUp; 92 93 /** the number of blocks in the cache */ 94 const unsigned numBlocks; 95 96 // Statistics 97 /** 98 * TODO: It would be good if these stats were acquired after warmup. 99 * @addtogroup CacheStatistics 100 * @{ 101 */ 102 103 /** Number of replacements of valid blocks per thread. */ 104 Stats::Vector replacements; 105 /** Per cycle average of the number of tags that hold valid data. */ 106 Stats::Average tagsInUse; 107 108 /** The total number of references to a block before it is replaced. */ 109 Stats::Scalar totalRefs; 110 111 /** 112 * The number of reference counts sampled. This is different from 113 * replacements because we sample all the valid blocks when the simulator 114 * exits. 115 */ 116 Stats::Scalar sampledRefs; 117 118 /** 119 * Average number of references to a block before is was replaced. 120 * @todo This should change to an average stat once we have them. 121 */ 122 Stats::Formula avgRefs; 123 124 /** The cycle that the warmup percentage was hit. 0 on failure. */ 125 Stats::Scalar warmupCycle; 126 127 /** Average occupancy of each requestor using the cache */ 128 Stats::AverageVector occupancies; 129 130 /** Average occ % of each requestor using the cache */ 131 Stats::Formula avgOccs; 132 133 /** Occupancy of each context/cpu using the cache */ 134 Stats::Vector occupanciesTaskId; 135 136 /** Occupancy of each context/cpu using the cache */ 137 Stats::Vector2d ageTaskId; 138 139 /** Occ % of each context/cpu using the cache */ 140 Stats::Formula percentOccsTaskId; 141 142 /** Number of tags consulted over all accesses. */ 143 Stats::Scalar tagAccesses; 144 /** Number of data blocks consulted over all accesses. */ 145 Stats::Scalar dataAccesses; 146 147 /** 148 * @} 149 */ 150 151 public: 152 typedef BaseTagsParams Params; 153 BaseTags(const Params *p); 154 155 /** 156 * Destructor. 157 */ 158 virtual ~BaseTags() {} 159 160 /** 161 * Set the parent cache back pointer. 162 * @param _cache Pointer to parent cache. 163 */ 164 void setCache(BaseCache *_cache); 165 166 /** 167 * Register local statistics. 168 */ 169 void regStats(); 170 171 /** 172 * Average in the reference count for valid blocks when the simulation 173 * exits. 174 */ 175 virtual void cleanupRefs() {} 176 177 /** 178 * Computes stats just prior to dump event 179 */ 180 virtual void computeStats() {} 181 182 /** 183 * Print all tags used 184 */ 185 virtual std::string print() const = 0; 186 187 /** 188 * Find a block using the memory address 189 */ 190 virtual CacheBlk * findBlock(Addr addr, bool is_secure) const = 0; 191 192 /** 193 * Align an address to the block size. 194 * @param addr the address to align. 195 * @return The block address. 196 */ 197 Addr blkAlign(Addr addr) const 198 { 199 return addr & ~blkMask; 200 } 201 202 /** 203 * Calculate the block offset of an address. 204 * @param addr the address to get the offset of. 205 * @return the block offset. 206 */ 207 int extractBlkOffset(Addr addr) const 208 { 209 return (addr & blkMask); 210 } 211 212 /** 213 * Find the cache block given set and way 214 * @param set The set of the block. 215 * @param way The way of the block. 216 * @return The cache block. 217 */ 218 virtual CacheBlk *findBlockBySetAndWay(int set, int way) const = 0; 219 220 /** 221 * Limit the allocation for the cache ways. 222 * @param ways The maximum number of ways available for replacement. 223 */ 224 virtual void setWayAllocationMax(int ways) 225 { 226 panic("This tag class does not implement way allocation limit!\n"); 227 } 228 229 /** 230 * Get the way allocation mask limit. 231 * @return The maximum number of ways available for replacement. 232 */ 233 virtual int getWayAllocationMax() const 234 { 235 panic("This tag class does not implement way allocation limit!\n"); 236 return -1; 237 } 238 239 /** 240 * This function updates the tags when a block is invalidated but 241 * does not invalidate the block itself. 242 * @param blk The block to invalidate. 243 */ 244 virtual void invalidate(CacheBlk *blk) 245 { 246 assert(blk); 247 assert(blk->isValid()); 248 tagsInUse--; 249 occupancies[blk->srcMasterId]--; 250 } 251 252 virtual CacheBlk* accessBlock(Addr addr, bool is_secure, Cycles &lat) = 0; 253 254 virtual Addr extractTag(Addr addr) const = 0; 255 256 virtual void insertBlock(PacketPtr pkt, CacheBlk *blk) = 0; 257 258 virtual Addr regenerateBlkAddr(Addr tag, unsigned set) const = 0; 259 260 virtual CacheBlk* findVictim(Addr addr) = 0; 261 262 virtual int extractSet(Addr addr) const = 0; 263 264 virtual void forEachBlk(CacheBlkVisitor &visitor) = 0; 265}; 266 267class BaseTagsCallback : public Callback 268{ 269 BaseTags *tags; 270 public: 271 BaseTagsCallback(BaseTags *t) : tags(t) {} 272 virtual void process() { tags->cleanupRefs(); }; 273}; 274 275class BaseTagsDumpCallback : public Callback 276{ 277 BaseTags *tags; 278 public: 279 BaseTagsDumpCallback(BaseTags *t) : tags(t) {} 280 virtual void process() { tags->computeStats(); }; 281}; 282 283#endif //__MEM_CACHE_TAGS_BASE_HH__ 284