gem5  v21.1.0.2
base_set_assoc.cc
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40 
47 
48 #include <string>
49 
50 #include "base/intmath.hh"
51 
52 namespace gem5
53 {
54 
56  :BaseTags(p), allocAssoc(p.assoc), blks(p.size / p.block_size),
57  sequentialAccess(p.sequential_access),
58  replacementPolicy(p.replacement_policy)
59 {
60  // There must be a indexing policy
61  fatal_if(!p.indexing_policy, "An indexing policy is required");
62 
63  // Check parameters
64  if (blkSize < 4 || !isPowerOf2(blkSize)) {
65  fatal("Block size must be at least 4 and a power of 2");
66  }
67 }
68 
69 void
71 {
72  // Initialize all blocks
73  for (unsigned blk_index = 0; blk_index < numBlocks; blk_index++) {
74  // Locate next cache block
75  CacheBlk* blk = &blks[blk_index];
76 
77  // Link block to indexing policy
78  indexingPolicy->setEntry(blk, blk_index);
79 
80  // Associate a data chunk to the block
81  blk->data = &dataBlks[blkSize*blk_index];
82 
83  // Associate a replacement data entry to the block
85  }
86 }
87 
88 void
90 {
92 
93  // Decrease the number of tags in use
94  stats.tagsInUse--;
95 
96  // Invalidate replacement data
98 }
99 
100 void
102 {
103  BaseTags::moveBlock(src_blk, dest_blk);
104 
105  // Since the blocks were using different replacement data pointers,
106  // we must touch the replacement data of the new entry, and invalidate
107  // the one that is being moved.
110 }
111 
112 } // namespace gem5
fatal
#define fatal(...)
This implements a cprintf based fatal() function.
Definition: logging.hh:189
gem5::replacement_policy::Base::reset
virtual void reset(const std::shared_ptr< ReplacementData > &replacement_data, const PacketPtr pkt)
Reset replacement data.
Definition: base.hh:90
gem5::BaseTags::stats
gem5::BaseTags::BaseTagStats stats
gem5::BaseSetAssoc::replacementPolicy
replacement_policy::Base * replacementPolicy
Replacement policy.
Definition: base_set_assoc.hh:88
gem5::BaseTags::numBlocks
const unsigned numBlocks
the number of blocks in the cache
Definition: base.hh:100
gem5::BaseTags::moveBlock
virtual void moveBlock(CacheBlk *src_blk, CacheBlk *dest_blk)
Move a block's metadata to another location decided by the replacement policy.
Definition: base.cc:130
gem5::isPowerOf2
static constexpr bool isPowerOf2(const T &n)
Definition: intmath.hh:98
gem5::CacheBlk
A Basic Cache block.
Definition: cache_blk.hh:70
gem5::replacement_policy::Base::instantiateEntry
virtual std::shared_ptr< ReplacementData > instantiateEntry()=0
Instantiate a replacement data entry.
gem5::BaseTags::Params
BaseTagsParams Params
Definition: base.hh:161
gem5::BaseSetAssoc::invalidate
void invalidate(CacheBlk *blk) override
This function updates the tags when a block is invalidated.
Definition: base_set_assoc.cc:89
gem5::MipsISA::p
Bitfield< 0 > p
Definition: pra_constants.hh:326
gem5::BaseSetAssoc::BaseSetAssoc
BaseSetAssoc(const Params &p)
Construct and initialize this tag store.
Definition: base_set_assoc.cc:55
gem5::CacheBlk::data
uint8_t * data
Contains a copy of the data in this block for easy access.
Definition: cache_blk.hh:103
gem5::BaseTags::BaseTagStats::tagsInUse
statistics::Average tagsInUse
Per tick average of the number of tags that hold valid data.
Definition: base.hh:118
gem5::BaseSetAssoc::blks
std::vector< CacheBlk > blks
The cache blocks.
Definition: base_set_assoc.hh:82
gem5::BaseIndexingPolicy::setEntry
void setEntry(ReplaceableEntry *entry, const uint64_t index)
Associate a pointer to an entry to its physical counterpart.
Definition: base.cc:81
gem5::BaseTags::blkSize
const unsigned blkSize
The block size of the cache.
Definition: base.hh:77
base_set_assoc.hh
gem5::ReplaceableEntry::replacementData
std::shared_ptr< replacement_policy::ReplacementData > replacementData
Replacement data associated to this entry.
Definition: replaceable_entry.hh:84
gem5::BaseTags::invalidate
virtual void invalidate(CacheBlk *blk)
This function updates the tags when a block is invalidated.
Definition: base.hh:254
gem5::BaseTags::indexingPolicy
BaseIndexingPolicy * indexingPolicy
Indexing policy.
Definition: base.hh:89
intmath.hh
fatal_if
#define fatal_if(cond,...)
Conditional fatal macro that checks the supplied condition and only causes a fatal error if the condi...
Definition: logging.hh:225
gem5::BaseTags
A common base class of Cache tagstore objects.
Definition: base.hh:73
gem5
Reference material can be found at the JEDEC website: UFS standard http://www.jedec....
Definition: decoder.cc:40
gem5::BaseSetAssoc::tagsInit
void tagsInit() override
Initialize blocks as CacheBlk instances.
Definition: base_set_assoc.cc:70
gem5::BaseTags::dataBlks
std::unique_ptr< uint8_t[]> dataBlks
The data blocks, 1 per cache block.
Definition: base.hh:103
gem5::BaseSetAssoc::moveBlock
void moveBlock(CacheBlk *src_blk, CacheBlk *dest_blk) override
Move a block's metadata to another location decided by the replacement policy.
Definition: base_set_assoc.cc:101
gem5::replacement_policy::Base::invalidate
virtual void invalidate(const std::shared_ptr< ReplacementData > &replacement_data)=0
Invalidate replacement data to set it as the next probable victim.

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