1/**
2 * Copyright (c) 2018 Metempsy Technology Consulting
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;
9 * redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution;
12 * neither the name of the copyright holders nor the names of its
13 * contributors may be used to endorse or promote products derived from
14 * this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Authors: Javier Bueno
29 */
30
31#ifndef __CACHE_PREFETCH_ASSOCIATIVE_SET_HH__
32#define __CACHE_PREFETCH_ASSOCIATIVE_SET_HH__
33
34#include "mem/cache/replacement_policies/base.hh"
35#include "mem/cache/replacement_policies/replaceable_entry.hh"
36#include "mem/cache/tags/indexing_policies/base.hh"
37
38/**
39 * Entry used for set-associative tables, usable with replacement policies
40 */
41class TaggedEntry : public ReplaceableEntry {
42 /** Tag for the entry */
43 Addr tag;
44 /** Valid bit */
45 bool valid;
46 /** Whether this entry refers to a memory area in the secure space */
47 bool secure;
48 public:
49 TaggedEntry() : tag(0), valid(false), secure(false) {}
50 virtual ~TaggedEntry() {}
51
52 /**
53 * Consult the valid bit
54 * @return True if the entry is valid
55 */
56 bool isValid() const
57 {
58 return valid;
59 }
60
61 /**
62 * Sets the entry to valid
63 */
64 void setValid()
65 {
66 valid = true;
67 }
68
69 /**
70 * Sets the entry to invalid
71 */
72 void setInvalid() {
73 valid = false;
74 }
75
76 /**
77 * Obtain the entry tag
78 * @return the tag value
79 */
80 Addr getTag() const
81 {
82 return tag;
83 }
84
85 /**
86 * Sets the tag of the entry
87 * @param t the tag value
88 */
89 void setTag(Addr t)
90 {
91 tag = t;
92 }
93
94 /**
95 * Consult if this entry refers to a memory in the secure area
96 * @return True if this entry refers to secure memory area
97 */
98 bool isSecure() const
99 {
100 return secure;
101 }
102
103 /**
104 * Sets the secure value bit
105 * @param s secure bit value
106 */
107 void setSecure(bool s)
108 {
109 secure = s;
110 }
111
112 /**
113 * Resets the entry, this is called when an entry is evicted to allocate
114 * a new one. Types inheriting this class should provide its own
115 * implementation
116 */
117 virtual void reset () {
118 }
119};
120
121/**
122 * Associative container based on the previosuly defined Entry type
123 * Each element is indexed by a key of type Addr, an additional
124 * bool value is used as an additional tag data of the entry.
125 */
126template<class Entry>
127class AssociativeSet {
128 static_assert(std::is_base_of<TaggedEntry, Entry>::value,
129 "Entry must derive from TaggedEntry");
130
131 /** Associativity of the container */
132 const int associativity;
133 /**
134 * Total number of entries, entries are organized in sets of the provided
135 * associativity. The number of associative sets is obtained by dividing
136 * numEntries by associativity.
137 */
138 const int numEntries;
139 /** Pointer to the indexing policy */
140 BaseIndexingPolicy* const indexingPolicy;
141 /** Pointer to the replacement policy */
142 BaseReplacementPolicy* const replacementPolicy;
143 /** Vector containing the entries of the container */
144 std::vector<Entry> entries;
145
146 public:
147 /**
148 * Public constructor
149 * @param assoc number of elements in each associative set
150 * @param num_entries total number of entries of the container, the number
151 * of sets can be calculated dividing this balue by the 'assoc' value
152 * @param idx_policy indexing policy
153 * @param rpl_policy replacement policy
154 * @param initial value of the elements of the set
155 */
156 AssociativeSet(int assoc, int num_entries, BaseIndexingPolicy *idx_policy,
157 BaseReplacementPolicy *rpl_policy, Entry const &init_value =
158 Entry());
159
160 /**
161 * Find an entry within the set
162 * @param addr key element
163 * @param is_secure tag element
164 * @return returns a pointer to the wanted entry or nullptr if it does not
165 * exist.
166 */
167 Entry* findEntry(Addr addr, bool is_secure) const;
168
169 /**
170 * Do an access to the entry, this is required to
171 * update the replacement information data.
172 * @param entry the accessed entry
173 */
174 void accessEntry(Entry *entry);
175
176 /**
177 * Find a victim to be replaced
178 * @param addr key to select the possible victim
179 * @result entry to be victimized
180 */
181 Entry* findVictim(Addr addr);
182
183 /**
184 * Find the set of entries that could be replaced given
185 * that we want to add a new entry with the provided key
186 * @param addr key to select the set of entries
187 * @result vector of candidates matching with the provided key
188 */
189 std::vector<Entry *> getPossibleEntries(const Addr addr) const;
190
191 /**
192 * Indicate that an entry has just been inserted
193 * @param addr key of the container
194 * @param is_secure tag component of the container
195 * @param entry pointer to the container entry to be inserted
196 */
197 void insertEntry(Addr addr, bool is_secure, Entry* entry);
| 1/**
2 * Copyright (c) 2018 Metempsy Technology Consulting
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;
9 * redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution;
12 * neither the name of the copyright holders nor the names of its
13 * contributors may be used to endorse or promote products derived from
14 * this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Authors: Javier Bueno
29 */
30
31#ifndef __CACHE_PREFETCH_ASSOCIATIVE_SET_HH__
32#define __CACHE_PREFETCH_ASSOCIATIVE_SET_HH__
33
34#include "mem/cache/replacement_policies/base.hh"
35#include "mem/cache/replacement_policies/replaceable_entry.hh"
36#include "mem/cache/tags/indexing_policies/base.hh"
37
38/**
39 * Entry used for set-associative tables, usable with replacement policies
40 */
41class TaggedEntry : public ReplaceableEntry {
42 /** Tag for the entry */
43 Addr tag;
44 /** Valid bit */
45 bool valid;
46 /** Whether this entry refers to a memory area in the secure space */
47 bool secure;
48 public:
49 TaggedEntry() : tag(0), valid(false), secure(false) {}
50 virtual ~TaggedEntry() {}
51
52 /**
53 * Consult the valid bit
54 * @return True if the entry is valid
55 */
56 bool isValid() const
57 {
58 return valid;
59 }
60
61 /**
62 * Sets the entry to valid
63 */
64 void setValid()
65 {
66 valid = true;
67 }
68
69 /**
70 * Sets the entry to invalid
71 */
72 void setInvalid() {
73 valid = false;
74 }
75
76 /**
77 * Obtain the entry tag
78 * @return the tag value
79 */
80 Addr getTag() const
81 {
82 return tag;
83 }
84
85 /**
86 * Sets the tag of the entry
87 * @param t the tag value
88 */
89 void setTag(Addr t)
90 {
91 tag = t;
92 }
93
94 /**
95 * Consult if this entry refers to a memory in the secure area
96 * @return True if this entry refers to secure memory area
97 */
98 bool isSecure() const
99 {
100 return secure;
101 }
102
103 /**
104 * Sets the secure value bit
105 * @param s secure bit value
106 */
107 void setSecure(bool s)
108 {
109 secure = s;
110 }
111
112 /**
113 * Resets the entry, this is called when an entry is evicted to allocate
114 * a new one. Types inheriting this class should provide its own
115 * implementation
116 */
117 virtual void reset () {
118 }
119};
120
121/**
122 * Associative container based on the previosuly defined Entry type
123 * Each element is indexed by a key of type Addr, an additional
124 * bool value is used as an additional tag data of the entry.
125 */
126template<class Entry>
127class AssociativeSet {
128 static_assert(std::is_base_of<TaggedEntry, Entry>::value,
129 "Entry must derive from TaggedEntry");
130
131 /** Associativity of the container */
132 const int associativity;
133 /**
134 * Total number of entries, entries are organized in sets of the provided
135 * associativity. The number of associative sets is obtained by dividing
136 * numEntries by associativity.
137 */
138 const int numEntries;
139 /** Pointer to the indexing policy */
140 BaseIndexingPolicy* const indexingPolicy;
141 /** Pointer to the replacement policy */
142 BaseReplacementPolicy* const replacementPolicy;
143 /** Vector containing the entries of the container */
144 std::vector<Entry> entries;
145
146 public:
147 /**
148 * Public constructor
149 * @param assoc number of elements in each associative set
150 * @param num_entries total number of entries of the container, the number
151 * of sets can be calculated dividing this balue by the 'assoc' value
152 * @param idx_policy indexing policy
153 * @param rpl_policy replacement policy
154 * @param initial value of the elements of the set
155 */
156 AssociativeSet(int assoc, int num_entries, BaseIndexingPolicy *idx_policy,
157 BaseReplacementPolicy *rpl_policy, Entry const &init_value =
158 Entry());
159
160 /**
161 * Find an entry within the set
162 * @param addr key element
163 * @param is_secure tag element
164 * @return returns a pointer to the wanted entry or nullptr if it does not
165 * exist.
166 */
167 Entry* findEntry(Addr addr, bool is_secure) const;
168
169 /**
170 * Do an access to the entry, this is required to
171 * update the replacement information data.
172 * @param entry the accessed entry
173 */
174 void accessEntry(Entry *entry);
175
176 /**
177 * Find a victim to be replaced
178 * @param addr key to select the possible victim
179 * @result entry to be victimized
180 */
181 Entry* findVictim(Addr addr);
182
183 /**
184 * Find the set of entries that could be replaced given
185 * that we want to add a new entry with the provided key
186 * @param addr key to select the set of entries
187 * @result vector of candidates matching with the provided key
188 */
189 std::vector<Entry *> getPossibleEntries(const Addr addr) const;
190
191 /**
192 * Indicate that an entry has just been inserted
193 * @param addr key of the container
194 * @param is_secure tag component of the container
195 * @param entry pointer to the container entry to be inserted
196 */
197 void insertEntry(Addr addr, bool is_secure, Entry* entry);
|