Prefetcher.py (13735:52ab3bab4f28) Prefetcher.py (13772:31b71dadc472)
1# Copyright (c) 2012, 2014 ARM Limited
2# All rights reserved.
3#
4# The license below extends only to copyright in the software and shall
5# not be construed as granting a license to any other intellectual
6# property including but not limited to intellectual property relating
7# to a hardware implementation of the functionality of the software
8# licensed hereunder. You may use the software subject to the license
9# terms below provided that you ensure that this notice is replicated
10# unmodified and in its entirety in all distributions of the software,
11# modified or unmodified, in source code or in binary form.
12#
13# Copyright (c) 2005 The Regents of The University of Michigan
14# All rights reserved.
15#
16# Redistribution and use in source and binary forms, with or without
17# modification, are permitted provided that the following conditions are
18# met: redistributions of source code must retain the above copyright
19# notice, this list of conditions and the following disclaimer;
20# redistributions in binary form must reproduce the above copyright
21# notice, this list of conditions and the following disclaimer in the
22# documentation and/or other materials provided with the distribution;
23# neither the name of the copyright holders nor the names of its
24# contributors may be used to endorse or promote products derived from
25# this software without specific prior written permission.
26#
27# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
28# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
29# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
30# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
31# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
32# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
33# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
34# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
35# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
36# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
37# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
38#
39# Authors: Ron Dreslinski
40# Mitch Hayenga
41
42from m5.SimObject import *
43from m5.params import *
44from m5.proxy import *
45
46from m5.objects.ClockedObject import ClockedObject
47from m5.objects.IndexingPolicies import *
48from m5.objects.ReplacementPolicies import *
49
50class HWPProbeEvent(object):
51 def __init__(self, prefetcher, obj, *listOfNames):
52 self.obj = obj
53 self.prefetcher = prefetcher
54 self.names = listOfNames
55
56 def register(self):
57 if self.obj:
58 for name in self.names:
59 self.prefetcher.getCCObject().addEventProbe(
60 self.obj.getCCObject(), name)
61
62class BasePrefetcher(ClockedObject):
63 type = 'BasePrefetcher'
64 abstract = True
65 cxx_header = "mem/cache/prefetch/base.hh"
66 cxx_exports = [
67 PyBindMethod("addEventProbe"),
68 ]
69 sys = Param.System(Parent.any, "System this prefetcher belongs to")
70
71 # Get the block size from the parent (system)
72 block_size = Param.Int(Parent.cache_line_size, "Block size in bytes")
73
74 on_miss = Param.Bool(False, "Only notify prefetcher on misses")
75 on_read = Param.Bool(True, "Notify prefetcher on reads")
76 on_write = Param.Bool(True, "Notify prefetcher on writes")
77 on_data = Param.Bool(True, "Notify prefetcher on data accesses")
78 on_inst = Param.Bool(True, "Notify prefetcher on instruction accesses")
79 prefetch_on_access = Param.Bool(Parent.prefetch_on_access,
80 "Notify the hardware prefetcher on every access (not just misses)")
81 use_virtual_addresses = Param.Bool(False,
82 "Use virtual addresses for prefetching")
83
84 _events = []
85 def addEvent(self, newObject):
86 self._events.append(newObject)
87
88 # Override the normal SimObject::regProbeListeners method and
89 # register deferred event handlers.
90 def regProbeListeners(self):
91 for event in self._events:
92 event.register()
93 self.getCCObject().regProbeListeners()
94
95 def listenFromProbe(self, simObj, *probeNames):
96 if not isinstance(simObj, SimObject):
97 raise TypeError("argument must be of SimObject type")
98 if len(probeNames) <= 0:
99 raise TypeError("probeNames must have at least one element")
100 self.addEvent(HWPProbeEvent(self, simObj, *probeNames))
101
102class QueuedPrefetcher(BasePrefetcher):
103 type = "QueuedPrefetcher"
104 abstract = True
105 cxx_class = "QueuedPrefetcher"
106 cxx_header = "mem/cache/prefetch/queued.hh"
107 latency = Param.Int(1, "Latency for generated prefetches")
108 queue_size = Param.Int(32, "Maximum number of queued prefetches")
109 queue_squash = Param.Bool(True, "Squash queued prefetch on demand access")
110 queue_filter = Param.Bool(True, "Don't queue redundant prefetches")
111 cache_snoop = Param.Bool(False, "Snoop cache to eliminate redundant request")
112
113 tag_prefetch = Param.Bool(True, "Tag prefetch with PC of generating access")
114
115class StridePrefetcher(QueuedPrefetcher):
116 type = 'StridePrefetcher'
117 cxx_class = 'StridePrefetcher'
118 cxx_header = "mem/cache/prefetch/stride.hh"
119
120 # Do not consult stride prefetcher on instruction accesses
121 on_inst = False
122
123 max_conf = Param.Int(7, "Maximum confidence level")
124 thresh_conf = Param.Int(4, "Threshold confidence level")
125 min_conf = Param.Int(0, "Minimum confidence level")
126 start_conf = Param.Int(4, "Starting confidence for new entries")
127
128 table_sets = Param.Int(16, "Number of sets in PC lookup table")
129 table_assoc = Param.Int(4, "Associativity of PC lookup table")
130 use_master_id = Param.Bool(True, "Use master id based history")
131
132 degree = Param.Int(4, "Number of prefetches to generate")
133
134 # Get replacement policy
135 replacement_policy = Param.BaseReplacementPolicy(RandomRP(),
136 "Replacement policy")
137
138class TaggedPrefetcher(QueuedPrefetcher):
139 type = 'TaggedPrefetcher'
140 cxx_class = 'TaggedPrefetcher'
141 cxx_header = "mem/cache/prefetch/tagged.hh"
142
143 degree = Param.Int(2, "Number of prefetches to generate")
144
1# Copyright (c) 2012, 2014 ARM Limited
2# All rights reserved.
3#
4# The license below extends only to copyright in the software and shall
5# not be construed as granting a license to any other intellectual
6# property including but not limited to intellectual property relating
7# to a hardware implementation of the functionality of the software
8# licensed hereunder. You may use the software subject to the license
9# terms below provided that you ensure that this notice is replicated
10# unmodified and in its entirety in all distributions of the software,
11# modified or unmodified, in source code or in binary form.
12#
13# Copyright (c) 2005 The Regents of The University of Michigan
14# All rights reserved.
15#
16# Redistribution and use in source and binary forms, with or without
17# modification, are permitted provided that the following conditions are
18# met: redistributions of source code must retain the above copyright
19# notice, this list of conditions and the following disclaimer;
20# redistributions in binary form must reproduce the above copyright
21# notice, this list of conditions and the following disclaimer in the
22# documentation and/or other materials provided with the distribution;
23# neither the name of the copyright holders nor the names of its
24# contributors may be used to endorse or promote products derived from
25# this software without specific prior written permission.
26#
27# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
28# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
29# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
30# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
31# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
32# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
33# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
34# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
35# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
36# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
37# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
38#
39# Authors: Ron Dreslinski
40# Mitch Hayenga
41
42from m5.SimObject import *
43from m5.params import *
44from m5.proxy import *
45
46from m5.objects.ClockedObject import ClockedObject
47from m5.objects.IndexingPolicies import *
48from m5.objects.ReplacementPolicies import *
49
50class HWPProbeEvent(object):
51 def __init__(self, prefetcher, obj, *listOfNames):
52 self.obj = obj
53 self.prefetcher = prefetcher
54 self.names = listOfNames
55
56 def register(self):
57 if self.obj:
58 for name in self.names:
59 self.prefetcher.getCCObject().addEventProbe(
60 self.obj.getCCObject(), name)
61
62class BasePrefetcher(ClockedObject):
63 type = 'BasePrefetcher'
64 abstract = True
65 cxx_header = "mem/cache/prefetch/base.hh"
66 cxx_exports = [
67 PyBindMethod("addEventProbe"),
68 ]
69 sys = Param.System(Parent.any, "System this prefetcher belongs to")
70
71 # Get the block size from the parent (system)
72 block_size = Param.Int(Parent.cache_line_size, "Block size in bytes")
73
74 on_miss = Param.Bool(False, "Only notify prefetcher on misses")
75 on_read = Param.Bool(True, "Notify prefetcher on reads")
76 on_write = Param.Bool(True, "Notify prefetcher on writes")
77 on_data = Param.Bool(True, "Notify prefetcher on data accesses")
78 on_inst = Param.Bool(True, "Notify prefetcher on instruction accesses")
79 prefetch_on_access = Param.Bool(Parent.prefetch_on_access,
80 "Notify the hardware prefetcher on every access (not just misses)")
81 use_virtual_addresses = Param.Bool(False,
82 "Use virtual addresses for prefetching")
83
84 _events = []
85 def addEvent(self, newObject):
86 self._events.append(newObject)
87
88 # Override the normal SimObject::regProbeListeners method and
89 # register deferred event handlers.
90 def regProbeListeners(self):
91 for event in self._events:
92 event.register()
93 self.getCCObject().regProbeListeners()
94
95 def listenFromProbe(self, simObj, *probeNames):
96 if not isinstance(simObj, SimObject):
97 raise TypeError("argument must be of SimObject type")
98 if len(probeNames) <= 0:
99 raise TypeError("probeNames must have at least one element")
100 self.addEvent(HWPProbeEvent(self, simObj, *probeNames))
101
102class QueuedPrefetcher(BasePrefetcher):
103 type = "QueuedPrefetcher"
104 abstract = True
105 cxx_class = "QueuedPrefetcher"
106 cxx_header = "mem/cache/prefetch/queued.hh"
107 latency = Param.Int(1, "Latency for generated prefetches")
108 queue_size = Param.Int(32, "Maximum number of queued prefetches")
109 queue_squash = Param.Bool(True, "Squash queued prefetch on demand access")
110 queue_filter = Param.Bool(True, "Don't queue redundant prefetches")
111 cache_snoop = Param.Bool(False, "Snoop cache to eliminate redundant request")
112
113 tag_prefetch = Param.Bool(True, "Tag prefetch with PC of generating access")
114
115class StridePrefetcher(QueuedPrefetcher):
116 type = 'StridePrefetcher'
117 cxx_class = 'StridePrefetcher'
118 cxx_header = "mem/cache/prefetch/stride.hh"
119
120 # Do not consult stride prefetcher on instruction accesses
121 on_inst = False
122
123 max_conf = Param.Int(7, "Maximum confidence level")
124 thresh_conf = Param.Int(4, "Threshold confidence level")
125 min_conf = Param.Int(0, "Minimum confidence level")
126 start_conf = Param.Int(4, "Starting confidence for new entries")
127
128 table_sets = Param.Int(16, "Number of sets in PC lookup table")
129 table_assoc = Param.Int(4, "Associativity of PC lookup table")
130 use_master_id = Param.Bool(True, "Use master id based history")
131
132 degree = Param.Int(4, "Number of prefetches to generate")
133
134 # Get replacement policy
135 replacement_policy = Param.BaseReplacementPolicy(RandomRP(),
136 "Replacement policy")
137
138class TaggedPrefetcher(QueuedPrefetcher):
139 type = 'TaggedPrefetcher'
140 cxx_class = 'TaggedPrefetcher'
141 cxx_header = "mem/cache/prefetch/tagged.hh"
142
143 degree = Param.Int(2, "Number of prefetches to generate")
144
145class IndirectMemoryPrefetcher(QueuedPrefetcher):
146 type = 'IndirectMemoryPrefetcher'
147 cxx_class = 'IndirectMemoryPrefetcher'
148 cxx_header = "mem/cache/prefetch/indirect_memory.hh"
149 pt_table_entries = Param.MemorySize("16",
150 "Number of entries of the Prefetch Table")
151 pt_table_assoc = Param.Unsigned(16, "Associativity of the Prefetch Table")
152 pt_table_indexing_policy = Param.BaseIndexingPolicy(
153 SetAssociative(entry_size = 1, assoc = Parent.pt_table_assoc,
154 size = Parent.pt_table_entries),
155 "Indexing policy of the pattern table")
156 pt_table_replacement_policy = Param.BaseReplacementPolicy(LRURP(),
157 "Replacement policy of the pattern table")
158 max_prefetch_distance = Param.Unsigned(16, "Maximum prefetch distance")
159 max_indirect_counter_value = Param.Unsigned(8,
160 "Maximum value of the indirect counter")
161 ipd_table_entries = Param.MemorySize("4",
162 "Number of entries of the Indirect Pattern Detector")
163 ipd_table_assoc = Param.Unsigned(4,
164 "Associativity of the Indirect Pattern Detector")
165 ipd_table_indexing_policy = Param.BaseIndexingPolicy(
166 SetAssociative(entry_size = 1, assoc = Parent.ipd_table_assoc,
167 size = Parent.ipd_table_entries),
168 "Indexing policy of the Indirect Pattern Detector")
169 ipd_table_replacement_policy = Param.BaseReplacementPolicy(LRURP(),
170 "Replacement policy of the Indirect Pattern Detector")
171 shift_values = VectorParam.Int([2, 3, 4, -3], "Shift values to evaluate")
172 addr_array_len = Param.Unsigned(4, "Number of misses tracked")
173 prefetch_threshold = Param.Unsigned(2,
174 "Counter threshold to start the indirect prefetching")
175 stream_counter_threshold = Param.Unsigned(4,
176 "Counter threshold to enable the stream prefetcher")
177 streaming_distance = Param.Unsigned(4,
178 "Number of prefetches to generate when using the stream prefetcher")
179
145class SignaturePathPrefetcher(QueuedPrefetcher):
146 type = 'SignaturePathPrefetcher'
147 cxx_class = 'SignaturePathPrefetcher'
148 cxx_header = "mem/cache/prefetch/signature_path.hh"
149
150 signature_shift = Param.UInt8(3,
151 "Number of bits to shift when calculating a new signature");
152 signature_bits = Param.UInt16(12,
153 "Size of the signature, in bits");
154 signature_table_entries = Param.MemorySize("1024",
155 "Number of entries of the signature table")
156 signature_table_assoc = Param.Unsigned(2,
157 "Associativity of the signature table")
158 signature_table_indexing_policy = Param.BaseIndexingPolicy(
159 SetAssociative(entry_size = 1, assoc = Parent.signature_table_assoc,
160 size = Parent.signature_table_entries),
161 "Indexing policy of the signature table")
162 signature_table_replacement_policy = Param.BaseReplacementPolicy(LRURP(),
163 "Replacement policy of the signature table")
164
165 max_counter_value = Param.UInt8(7, "Maximum pattern counter value")
166 pattern_table_entries = Param.MemorySize("4096",
167 "Number of entries of the pattern table")
168 pattern_table_assoc = Param.Unsigned(1,
169 "Associativity of the pattern table")
170 strides_per_pattern_entry = Param.Unsigned(4,
171 "Number of strides stored in each pattern entry")
172 pattern_table_indexing_policy = Param.BaseIndexingPolicy(
173 SetAssociative(entry_size = 1, assoc = Parent.pattern_table_assoc,
174 size = Parent.pattern_table_entries),
175 "Indexing policy of the pattern table")
176 pattern_table_replacement_policy = Param.BaseReplacementPolicy(LRURP(),
177 "Replacement policy of the pattern table")
178
179 prefetch_confidence_threshold = Param.Float(0.5,
180 "Minimum confidence to issue prefetches")
181 lookahead_confidence_threshold = Param.Float(0.75,
182 "Minimum confidence to continue exploring lookahead entries")
183
184class SignaturePathPrefetcherV2(SignaturePathPrefetcher):
185 type = 'SignaturePathPrefetcherV2'
186 cxx_class = 'SignaturePathPrefetcherV2'
187 cxx_header = "mem/cache/prefetch/signature_path_v2.hh"
188
189 signature_table_entries = "256"
190 signature_table_assoc = 1
191 pattern_table_entries = "512"
192 pattern_table_assoc = 1
193 max_counter_value = 15
194 prefetch_confidence_threshold = 0.25
195 lookahead_confidence_threshold = 0.25
196
197 global_history_register_entries = Param.MemorySize("8",
198 "Number of entries of global history register")
199 global_history_register_indexing_policy = Param.BaseIndexingPolicy(
200 SetAssociative(entry_size = 1,
201 assoc = Parent.global_history_register_entries,
202 size = Parent.global_history_register_entries),
203 "Indexing policy of the global history register")
204 global_history_register_replacement_policy = Param.BaseReplacementPolicy(
205 LRURP(), "Replacement policy of the global history register")
206
207class AccessMapPatternMatching(ClockedObject):
208 type = 'AccessMapPatternMatching'
209 cxx_class = 'AccessMapPatternMatching'
210 cxx_header = "mem/cache/prefetch/access_map_pattern_matching.hh"
211
212 block_size = Param.Unsigned(Parent.block_size,
213 "Cacheline size used by the prefetcher using this object")
214
215 limit_stride = Param.Unsigned(0,
216 "Limit the strides checked up to -X/X, if 0, disable the limit")
217 start_degree = Param.Unsigned(4,
218 "Initial degree (Maximum number of prefetches generated")
219 hot_zone_size = Param.MemorySize("2kB", "Memory covered by a hot zone")
220 access_map_table_entries = Param.MemorySize("256",
221 "Number of entries in the access map table")
222 access_map_table_assoc = Param.Unsigned(8,
223 "Associativity of the access map table")
224 access_map_table_indexing_policy = Param.BaseIndexingPolicy(
225 SetAssociative(entry_size = 1, assoc = Parent.access_map_table_assoc,
226 size = Parent.access_map_table_entries),
227 "Indexing policy of the access map table")
228 access_map_table_replacement_policy = Param.BaseReplacementPolicy(LRURP(),
229 "Replacement policy of the access map table")
230 high_coverage_threshold = Param.Float(0.25,
231 "A prefetch coverage factor bigger than this is considered high")
232 low_coverage_threshold = Param.Float(0.125,
233 "A prefetch coverage factor smaller than this is considered low")
234 high_accuracy_threshold = Param.Float(0.5,
235 "A prefetch accuracy factor bigger than this is considered high")
236 low_accuracy_threshold = Param.Float(0.25,
237 "A prefetch accuracy factor smaller than this is considered low")
238 high_cache_hit_threshold = Param.Float(0.875,
239 "A cache hit ratio bigger than this is considered high")
240 low_cache_hit_threshold = Param.Float(0.75,
241 "A cache hit ratio smaller than this is considered low")
242 epoch_cycles = Param.Cycles(256000, "Cycles in an epoch period")
243 offchip_memory_latency = Param.Latency("30ns",
244 "Memory latency used to compute the required memory bandwidth")
245
246class AMPMPrefetcher(QueuedPrefetcher):
247 type = 'AMPMPrefetcher'
248 cxx_class = 'AMPMPrefetcher'
249 cxx_header = "mem/cache/prefetch/access_map_pattern_matching.hh"
250 ampm = Param.AccessMapPatternMatching( AccessMapPatternMatching(),
251 "Access Map Pattern Matching object")
252
253class DeltaCorrelatingPredictionTables(SimObject):
254 type = 'DeltaCorrelatingPredictionTables'
255 cxx_class = 'DeltaCorrelatingPredictionTables'
256 cxx_header = "mem/cache/prefetch/delta_correlating_prediction_tables.hh"
257 deltas_per_entry = Param.Unsigned(20,
258 "Number of deltas stored in each table entry")
259 delta_bits = Param.Unsigned(12, "Bits per delta")
260 delta_mask_bits = Param.Unsigned(8,
261 "Lower bits to mask when comparing deltas")
262 table_entries = Param.MemorySize("128",
263 "Number of entries in the table")
264 table_assoc = Param.Unsigned(128,
265 "Associativity of the table")
266 table_indexing_policy = Param.BaseIndexingPolicy(
267 SetAssociative(entry_size = 1, assoc = Parent.table_assoc,
268 size = Parent.table_entries),
269 "Indexing policy of the table")
270 table_replacement_policy = Param.BaseReplacementPolicy(LRURP(),
271 "Replacement policy of the table")
272
273class DCPTPrefetcher(QueuedPrefetcher):
274 type = 'DCPTPrefetcher'
275 cxx_class = 'DCPTPrefetcher'
276 cxx_header = "mem/cache/prefetch/delta_correlating_prediction_tables.hh"
277 dcpt = Param.DeltaCorrelatingPredictionTables(
278 DeltaCorrelatingPredictionTables(),
279 "Delta Correlating Prediction Tables object")
280
281class IrregularStreamBufferPrefetcher(QueuedPrefetcher):
282 type = "IrregularStreamBufferPrefetcher"
283 cxx_class = "IrregularStreamBufferPrefetcher"
284 cxx_header = "mem/cache/prefetch/irregular_stream_buffer.hh"
285
286 max_counter_value = Param.Unsigned(3,
287 "Maximum value of the confidence counter")
288 chunk_size = Param.Unsigned(256,
289 "Maximum number of addresses in a temporal stream")
290 degree = Param.Unsigned(4, "Number of prefetches to generate")
291 training_unit_assoc = Param.Unsigned(128,
292 "Associativity of the training unit")
293 training_unit_entries = Param.MemorySize("128",
294 "Number of entries of the training unit")
295 training_unit_indexing_policy = Param.BaseIndexingPolicy(
296 SetAssociative(entry_size = 1, assoc = Parent.training_unit_assoc,
297 size = Parent.training_unit_entries),
298 "Indexing policy of the training unit")
299 training_unit_replacement_policy = Param.BaseReplacementPolicy(LRURP(),
300 "Replacement policy of the training unit")
301
302 prefetch_candidates_per_entry = Param.Unsigned(16,
303 "Number of prefetch candidates stored in a SP-AMC entry")
304 address_map_cache_assoc = Param.Unsigned(128,
305 "Associativity of the PS/SP AMCs")
306 address_map_cache_entries = Param.MemorySize("128",
307 "Number of entries of the PS/SP AMCs")
308 ps_address_map_cache_indexing_policy = Param.BaseIndexingPolicy(
309 SetAssociative(entry_size = 1,
310 assoc = Parent.address_map_cache_assoc,
311 size = Parent.address_map_cache_entries),
312 "Indexing policy of the Physical-to-Structural Address Map Cache")
313 ps_address_map_cache_replacement_policy = Param.BaseReplacementPolicy(
314 LRURP(),
315 "Replacement policy of the Physical-to-Structural Address Map Cache")
316 sp_address_map_cache_indexing_policy = Param.BaseIndexingPolicy(
317 SetAssociative(entry_size = 1,
318 assoc = Parent.address_map_cache_assoc,
319 size = Parent.address_map_cache_entries),
320 "Indexing policy of the Structural-to-Physical Address Mao Cache")
321 sp_address_map_cache_replacement_policy = Param.BaseReplacementPolicy(
322 LRURP(),
323 "Replacement policy of the Structural-to-Physical Address Map Cache")
324
325class SlimAccessMapPatternMatching(AccessMapPatternMatching):
326 start_degree = 2
327 limit_stride = 4
328
329class SlimDeltaCorrelatingPredictionTables(DeltaCorrelatingPredictionTables):
330 table_entries = "256"
331 table_assoc = 256
332 deltas_per_entry = 9
333
334class SlimAMPMPrefetcher(QueuedPrefetcher):
335 type = 'SlimAMPMPrefetcher'
336 cxx_class = 'SlimAMPMPrefetcher'
337 cxx_header = "mem/cache/prefetch/slim_ampm.hh"
338
339 ampm = Param.AccessMapPatternMatching(SlimAccessMapPatternMatching(),
340 "Access Map Pattern Matching object")
341 dcpt = Param.DeltaCorrelatingPredictionTables(
342 SlimDeltaCorrelatingPredictionTables(),
343 "Delta Correlating Prediction Tables object")
344
345class BOPPrefetcher(QueuedPrefetcher):
346 type = "BOPPrefetcher"
347 cxx_class = "BOPPrefetcher"
348 cxx_header = "mem/cache/prefetch/bop.hh"
349 score_max = Param.Unsigned(31, "Max. score to update the best offset")
350 round_max = Param.Unsigned(100, "Max. round to update the best offset")
351 bad_score = Param.Unsigned(10, "Score at which the HWP is disabled")
352 rr_size = Param.Unsigned(64, "Number of entries of each RR bank")
353 tag_bits = Param.Unsigned(12, "Bits used to store the tag")
354 offset_list_size = Param.Unsigned(46,
355 "Number of entries in the offsets list")
356 negative_offsets_enable = Param.Bool(True,
357 "Initialize the offsets list also with negative values \
358 (i.e. the table will have half of the entries with positive \
359 offsets and the other half with negative ones)")
360 delay_queue_enable = Param.Bool(True, "Enable the delay queue")
361 delay_queue_size = Param.Unsigned(15,
362 "Number of entries in the delay queue")
363 delay_queue_cycles = Param.Cycles(60,
364 "Cycles to delay a write in the left RR table from the delay \
365 queue")
366
367class SBOOEPrefetcher(QueuedPrefetcher):
368 type = 'SBOOEPrefetcher'
369 cxx_class = 'SBOOEPrefetcher'
370 cxx_header = "mem/cache/prefetch/sbooe.hh"
371 latency_buffer_size = Param.Int(32, "Entries in the latency buffer")
372 sequential_prefetchers = Param.Int(9, "Number of sequential prefetchers")
373 sandbox_entries = Param.Int(1024, "Size of the address buffer")
374 score_threshold_pct = Param.Percent(25, "Min. threshold to issue a \
375 prefetch. The value is the percentage of sandbox entries to use")
180class SignaturePathPrefetcher(QueuedPrefetcher):
181 type = 'SignaturePathPrefetcher'
182 cxx_class = 'SignaturePathPrefetcher'
183 cxx_header = "mem/cache/prefetch/signature_path.hh"
184
185 signature_shift = Param.UInt8(3,
186 "Number of bits to shift when calculating a new signature");
187 signature_bits = Param.UInt16(12,
188 "Size of the signature, in bits");
189 signature_table_entries = Param.MemorySize("1024",
190 "Number of entries of the signature table")
191 signature_table_assoc = Param.Unsigned(2,
192 "Associativity of the signature table")
193 signature_table_indexing_policy = Param.BaseIndexingPolicy(
194 SetAssociative(entry_size = 1, assoc = Parent.signature_table_assoc,
195 size = Parent.signature_table_entries),
196 "Indexing policy of the signature table")
197 signature_table_replacement_policy = Param.BaseReplacementPolicy(LRURP(),
198 "Replacement policy of the signature table")
199
200 max_counter_value = Param.UInt8(7, "Maximum pattern counter value")
201 pattern_table_entries = Param.MemorySize("4096",
202 "Number of entries of the pattern table")
203 pattern_table_assoc = Param.Unsigned(1,
204 "Associativity of the pattern table")
205 strides_per_pattern_entry = Param.Unsigned(4,
206 "Number of strides stored in each pattern entry")
207 pattern_table_indexing_policy = Param.BaseIndexingPolicy(
208 SetAssociative(entry_size = 1, assoc = Parent.pattern_table_assoc,
209 size = Parent.pattern_table_entries),
210 "Indexing policy of the pattern table")
211 pattern_table_replacement_policy = Param.BaseReplacementPolicy(LRURP(),
212 "Replacement policy of the pattern table")
213
214 prefetch_confidence_threshold = Param.Float(0.5,
215 "Minimum confidence to issue prefetches")
216 lookahead_confidence_threshold = Param.Float(0.75,
217 "Minimum confidence to continue exploring lookahead entries")
218
219class SignaturePathPrefetcherV2(SignaturePathPrefetcher):
220 type = 'SignaturePathPrefetcherV2'
221 cxx_class = 'SignaturePathPrefetcherV2'
222 cxx_header = "mem/cache/prefetch/signature_path_v2.hh"
223
224 signature_table_entries = "256"
225 signature_table_assoc = 1
226 pattern_table_entries = "512"
227 pattern_table_assoc = 1
228 max_counter_value = 15
229 prefetch_confidence_threshold = 0.25
230 lookahead_confidence_threshold = 0.25
231
232 global_history_register_entries = Param.MemorySize("8",
233 "Number of entries of global history register")
234 global_history_register_indexing_policy = Param.BaseIndexingPolicy(
235 SetAssociative(entry_size = 1,
236 assoc = Parent.global_history_register_entries,
237 size = Parent.global_history_register_entries),
238 "Indexing policy of the global history register")
239 global_history_register_replacement_policy = Param.BaseReplacementPolicy(
240 LRURP(), "Replacement policy of the global history register")
241
242class AccessMapPatternMatching(ClockedObject):
243 type = 'AccessMapPatternMatching'
244 cxx_class = 'AccessMapPatternMatching'
245 cxx_header = "mem/cache/prefetch/access_map_pattern_matching.hh"
246
247 block_size = Param.Unsigned(Parent.block_size,
248 "Cacheline size used by the prefetcher using this object")
249
250 limit_stride = Param.Unsigned(0,
251 "Limit the strides checked up to -X/X, if 0, disable the limit")
252 start_degree = Param.Unsigned(4,
253 "Initial degree (Maximum number of prefetches generated")
254 hot_zone_size = Param.MemorySize("2kB", "Memory covered by a hot zone")
255 access_map_table_entries = Param.MemorySize("256",
256 "Number of entries in the access map table")
257 access_map_table_assoc = Param.Unsigned(8,
258 "Associativity of the access map table")
259 access_map_table_indexing_policy = Param.BaseIndexingPolicy(
260 SetAssociative(entry_size = 1, assoc = Parent.access_map_table_assoc,
261 size = Parent.access_map_table_entries),
262 "Indexing policy of the access map table")
263 access_map_table_replacement_policy = Param.BaseReplacementPolicy(LRURP(),
264 "Replacement policy of the access map table")
265 high_coverage_threshold = Param.Float(0.25,
266 "A prefetch coverage factor bigger than this is considered high")
267 low_coverage_threshold = Param.Float(0.125,
268 "A prefetch coverage factor smaller than this is considered low")
269 high_accuracy_threshold = Param.Float(0.5,
270 "A prefetch accuracy factor bigger than this is considered high")
271 low_accuracy_threshold = Param.Float(0.25,
272 "A prefetch accuracy factor smaller than this is considered low")
273 high_cache_hit_threshold = Param.Float(0.875,
274 "A cache hit ratio bigger than this is considered high")
275 low_cache_hit_threshold = Param.Float(0.75,
276 "A cache hit ratio smaller than this is considered low")
277 epoch_cycles = Param.Cycles(256000, "Cycles in an epoch period")
278 offchip_memory_latency = Param.Latency("30ns",
279 "Memory latency used to compute the required memory bandwidth")
280
281class AMPMPrefetcher(QueuedPrefetcher):
282 type = 'AMPMPrefetcher'
283 cxx_class = 'AMPMPrefetcher'
284 cxx_header = "mem/cache/prefetch/access_map_pattern_matching.hh"
285 ampm = Param.AccessMapPatternMatching( AccessMapPatternMatching(),
286 "Access Map Pattern Matching object")
287
288class DeltaCorrelatingPredictionTables(SimObject):
289 type = 'DeltaCorrelatingPredictionTables'
290 cxx_class = 'DeltaCorrelatingPredictionTables'
291 cxx_header = "mem/cache/prefetch/delta_correlating_prediction_tables.hh"
292 deltas_per_entry = Param.Unsigned(20,
293 "Number of deltas stored in each table entry")
294 delta_bits = Param.Unsigned(12, "Bits per delta")
295 delta_mask_bits = Param.Unsigned(8,
296 "Lower bits to mask when comparing deltas")
297 table_entries = Param.MemorySize("128",
298 "Number of entries in the table")
299 table_assoc = Param.Unsigned(128,
300 "Associativity of the table")
301 table_indexing_policy = Param.BaseIndexingPolicy(
302 SetAssociative(entry_size = 1, assoc = Parent.table_assoc,
303 size = Parent.table_entries),
304 "Indexing policy of the table")
305 table_replacement_policy = Param.BaseReplacementPolicy(LRURP(),
306 "Replacement policy of the table")
307
308class DCPTPrefetcher(QueuedPrefetcher):
309 type = 'DCPTPrefetcher'
310 cxx_class = 'DCPTPrefetcher'
311 cxx_header = "mem/cache/prefetch/delta_correlating_prediction_tables.hh"
312 dcpt = Param.DeltaCorrelatingPredictionTables(
313 DeltaCorrelatingPredictionTables(),
314 "Delta Correlating Prediction Tables object")
315
316class IrregularStreamBufferPrefetcher(QueuedPrefetcher):
317 type = "IrregularStreamBufferPrefetcher"
318 cxx_class = "IrregularStreamBufferPrefetcher"
319 cxx_header = "mem/cache/prefetch/irregular_stream_buffer.hh"
320
321 max_counter_value = Param.Unsigned(3,
322 "Maximum value of the confidence counter")
323 chunk_size = Param.Unsigned(256,
324 "Maximum number of addresses in a temporal stream")
325 degree = Param.Unsigned(4, "Number of prefetches to generate")
326 training_unit_assoc = Param.Unsigned(128,
327 "Associativity of the training unit")
328 training_unit_entries = Param.MemorySize("128",
329 "Number of entries of the training unit")
330 training_unit_indexing_policy = Param.BaseIndexingPolicy(
331 SetAssociative(entry_size = 1, assoc = Parent.training_unit_assoc,
332 size = Parent.training_unit_entries),
333 "Indexing policy of the training unit")
334 training_unit_replacement_policy = Param.BaseReplacementPolicy(LRURP(),
335 "Replacement policy of the training unit")
336
337 prefetch_candidates_per_entry = Param.Unsigned(16,
338 "Number of prefetch candidates stored in a SP-AMC entry")
339 address_map_cache_assoc = Param.Unsigned(128,
340 "Associativity of the PS/SP AMCs")
341 address_map_cache_entries = Param.MemorySize("128",
342 "Number of entries of the PS/SP AMCs")
343 ps_address_map_cache_indexing_policy = Param.BaseIndexingPolicy(
344 SetAssociative(entry_size = 1,
345 assoc = Parent.address_map_cache_assoc,
346 size = Parent.address_map_cache_entries),
347 "Indexing policy of the Physical-to-Structural Address Map Cache")
348 ps_address_map_cache_replacement_policy = Param.BaseReplacementPolicy(
349 LRURP(),
350 "Replacement policy of the Physical-to-Structural Address Map Cache")
351 sp_address_map_cache_indexing_policy = Param.BaseIndexingPolicy(
352 SetAssociative(entry_size = 1,
353 assoc = Parent.address_map_cache_assoc,
354 size = Parent.address_map_cache_entries),
355 "Indexing policy of the Structural-to-Physical Address Mao Cache")
356 sp_address_map_cache_replacement_policy = Param.BaseReplacementPolicy(
357 LRURP(),
358 "Replacement policy of the Structural-to-Physical Address Map Cache")
359
360class SlimAccessMapPatternMatching(AccessMapPatternMatching):
361 start_degree = 2
362 limit_stride = 4
363
364class SlimDeltaCorrelatingPredictionTables(DeltaCorrelatingPredictionTables):
365 table_entries = "256"
366 table_assoc = 256
367 deltas_per_entry = 9
368
369class SlimAMPMPrefetcher(QueuedPrefetcher):
370 type = 'SlimAMPMPrefetcher'
371 cxx_class = 'SlimAMPMPrefetcher'
372 cxx_header = "mem/cache/prefetch/slim_ampm.hh"
373
374 ampm = Param.AccessMapPatternMatching(SlimAccessMapPatternMatching(),
375 "Access Map Pattern Matching object")
376 dcpt = Param.DeltaCorrelatingPredictionTables(
377 SlimDeltaCorrelatingPredictionTables(),
378 "Delta Correlating Prediction Tables object")
379
380class BOPPrefetcher(QueuedPrefetcher):
381 type = "BOPPrefetcher"
382 cxx_class = "BOPPrefetcher"
383 cxx_header = "mem/cache/prefetch/bop.hh"
384 score_max = Param.Unsigned(31, "Max. score to update the best offset")
385 round_max = Param.Unsigned(100, "Max. round to update the best offset")
386 bad_score = Param.Unsigned(10, "Score at which the HWP is disabled")
387 rr_size = Param.Unsigned(64, "Number of entries of each RR bank")
388 tag_bits = Param.Unsigned(12, "Bits used to store the tag")
389 offset_list_size = Param.Unsigned(46,
390 "Number of entries in the offsets list")
391 negative_offsets_enable = Param.Bool(True,
392 "Initialize the offsets list also with negative values \
393 (i.e. the table will have half of the entries with positive \
394 offsets and the other half with negative ones)")
395 delay_queue_enable = Param.Bool(True, "Enable the delay queue")
396 delay_queue_size = Param.Unsigned(15,
397 "Number of entries in the delay queue")
398 delay_queue_cycles = Param.Cycles(60,
399 "Cycles to delay a write in the left RR table from the delay \
400 queue")
401
402class SBOOEPrefetcher(QueuedPrefetcher):
403 type = 'SBOOEPrefetcher'
404 cxx_class = 'SBOOEPrefetcher'
405 cxx_header = "mem/cache/prefetch/sbooe.hh"
406 latency_buffer_size = Param.Int(32, "Entries in the latency buffer")
407 sequential_prefetchers = Param.Int(9, "Number of sequential prefetchers")
408 sandbox_entries = Param.Int(1024, "Size of the address buffer")
409 score_threshold_pct = Param.Percent(25, "Min. threshold to issue a \
410 prefetch. The value is the percentage of sandbox entries to use")