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.BaseCPU import BaseCPU
47from m5.objects.ClockedObject import ClockedObject
48from m5.objects.IndexingPolicies import *
49from m5.objects.ReplacementPolicies import *
50
51class HWPProbeEvent(object):
52 def __init__(self, prefetcher, obj, *listOfNames):
53 self.obj = obj
54 self.prefetcher = prefetcher
55 self.names = listOfNames
56
57 def register(self):
58 if self.obj:
59 for name in self.names:
60 self.prefetcher.getCCObject().addEventProbe(
61 self.obj.getCCObject(), name)
62
63class BasePrefetcher(ClockedObject):
64 type = 'BasePrefetcher'
65 abstract = True
66 cxx_header = "mem/cache/prefetch/base.hh"
67 cxx_exports = [
68 PyBindMethod("addEventProbe"),
69 ]
70 sys = Param.System(Parent.any, "System this prefetcher belongs to")
71
72 # Get the block size from the parent (system)
73 block_size = Param.Int(Parent.cache_line_size, "Block size in bytes")
74
75 on_miss = Param.Bool(False, "Only notify prefetcher on misses")
76 on_read = Param.Bool(True, "Notify prefetcher on reads")
77 on_write = Param.Bool(True, "Notify prefetcher on writes")
78 on_data = Param.Bool(True, "Notify prefetcher on data accesses")
79 on_inst = Param.Bool(True, "Notify prefetcher on instruction accesses")
80 prefetch_on_access = Param.Bool(Parent.prefetch_on_access,
81 "Notify the hardware prefetcher on every access (not just misses)")
82 use_virtual_addresses = Param.Bool(False,
83 "Use virtual addresses for prefetching")
84
85 _events = []
86 def addEvent(self, newObject):
87 self._events.append(newObject)
88
89 # Override the normal SimObject::regProbeListeners method and
90 # register deferred event handlers.
91 def regProbeListeners(self):
92 for event in self._events:
93 event.register()
94 self.getCCObject().regProbeListeners()
95
96 def listenFromProbe(self, simObj, *probeNames):
97 if not isinstance(simObj, SimObject):
98 raise TypeError("argument must be of SimObject type")
99 if len(probeNames) <= 0:
100 raise TypeError("probeNames must have at least one element")
101 self.addEvent(HWPProbeEvent(self, simObj, *probeNames))
102
103class QueuedPrefetcher(BasePrefetcher):
104 type = "QueuedPrefetcher"
105 abstract = True
106 cxx_class = "QueuedPrefetcher"
107 cxx_header = "mem/cache/prefetch/queued.hh"
108 latency = Param.Int(1, "Latency for generated prefetches")
109 queue_size = Param.Int(32, "Maximum number of queued prefetches")
110 queue_squash = Param.Bool(True, "Squash queued prefetch on demand access")
111 queue_filter = Param.Bool(True, "Don't queue redundant prefetches")
112 cache_snoop = Param.Bool(False, "Snoop cache to eliminate redundant request")
113
114 tag_prefetch = Param.Bool(True, "Tag prefetch with PC of generating access")
115
116class StridePrefetcher(QueuedPrefetcher):
117 type = 'StridePrefetcher'
118 cxx_class = 'StridePrefetcher'
119 cxx_header = "mem/cache/prefetch/stride.hh"
120
121 # Do not consult stride prefetcher on instruction accesses
122 on_inst = False
123
124 max_conf = Param.Int(7, "Maximum confidence level")
125 thresh_conf = Param.Int(4, "Threshold confidence level")
126 min_conf = Param.Int(0, "Minimum confidence level")
127 start_conf = Param.Int(4, "Starting confidence for new entries")
128
129 table_sets = Param.Int(16, "Number of sets in PC lookup table")
130 table_assoc = Param.Int(4, "Associativity of PC lookup table")
131 use_master_id = Param.Bool(True, "Use master id based history")
132
133 degree = Param.Int(4, "Number of prefetches to generate")
134
135 # Get replacement policy
136 replacement_policy = Param.BaseReplacementPolicy(RandomRP(),
137 "Replacement policy")
138
139class TaggedPrefetcher(QueuedPrefetcher):
140 type = 'TaggedPrefetcher'
141 cxx_class = 'TaggedPrefetcher'
142 cxx_header = "mem/cache/prefetch/tagged.hh"
143
144 degree = Param.Int(2, "Number of prefetches to generate")
145
146class IndirectMemoryPrefetcher(QueuedPrefetcher):
147 type = 'IndirectMemoryPrefetcher'
148 cxx_class = 'IndirectMemoryPrefetcher'
149 cxx_header = "mem/cache/prefetch/indirect_memory.hh"
150 pt_table_entries = Param.MemorySize("16",
151 "Number of entries of the Prefetch Table")
152 pt_table_assoc = Param.Unsigned(16, "Associativity of the Prefetch Table")
153 pt_table_indexing_policy = Param.BaseIndexingPolicy(
154 SetAssociative(entry_size = 1, assoc = Parent.pt_table_assoc,
155 size = Parent.pt_table_entries),
156 "Indexing policy of the pattern table")
157 pt_table_replacement_policy = Param.BaseReplacementPolicy(LRURP(),
158 "Replacement policy of the pattern table")
159 max_prefetch_distance = Param.Unsigned(16, "Maximum prefetch distance")
160 max_indirect_counter_value = Param.Unsigned(8,
161 "Maximum value of the indirect counter")
162 ipd_table_entries = Param.MemorySize("4",
163 "Number of entries of the Indirect Pattern Detector")
164 ipd_table_assoc = Param.Unsigned(4,
165 "Associativity of the Indirect Pattern Detector")
166 ipd_table_indexing_policy = Param.BaseIndexingPolicy(
167 SetAssociative(entry_size = 1, assoc = Parent.ipd_table_assoc,
168 size = Parent.ipd_table_entries),
169 "Indexing policy of the Indirect Pattern Detector")
170 ipd_table_replacement_policy = Param.BaseReplacementPolicy(LRURP(),
171 "Replacement policy of the Indirect Pattern Detector")
172 shift_values = VectorParam.Int([2, 3, 4, -3], "Shift values to evaluate")
173 addr_array_len = Param.Unsigned(4, "Number of misses tracked")
174 prefetch_threshold = Param.Unsigned(2,
175 "Counter threshold to start the indirect prefetching")
176 stream_counter_threshold = Param.Unsigned(4,
177 "Counter threshold to enable the stream prefetcher")
178 streaming_distance = Param.Unsigned(4,
179 "Number of prefetches to generate when using the stream prefetcher")
180
181class SignaturePathPrefetcher(QueuedPrefetcher):
182 type = 'SignaturePathPrefetcher'
183 cxx_class = 'SignaturePathPrefetcher'
184 cxx_header = "mem/cache/prefetch/signature_path.hh"
185
186 signature_shift = Param.UInt8(3,
187 "Number of bits to shift when calculating a new signature");
188 signature_bits = Param.UInt16(12,
189 "Size of the signature, in bits");
190 signature_table_entries = Param.MemorySize("1024",
191 "Number of entries of the signature table")
192 signature_table_assoc = Param.Unsigned(2,
193 "Associativity of the signature table")
194 signature_table_indexing_policy = Param.BaseIndexingPolicy(
195 SetAssociative(entry_size = 1, assoc = Parent.signature_table_assoc,
196 size = Parent.signature_table_entries),
197 "Indexing policy of the signature table")
198 signature_table_replacement_policy = Param.BaseReplacementPolicy(LRURP(),
199 "Replacement policy of the signature table")
200
201 max_counter_value = Param.UInt8(7, "Maximum pattern counter value")
202 pattern_table_entries = Param.MemorySize("4096",
203 "Number of entries of the pattern table")
204 pattern_table_assoc = Param.Unsigned(1,
205 "Associativity of the pattern table")
206 strides_per_pattern_entry = Param.Unsigned(4,
207 "Number of strides stored in each pattern entry")
208 pattern_table_indexing_policy = Param.BaseIndexingPolicy(
209 SetAssociative(entry_size = 1, assoc = Parent.pattern_table_assoc,
210 size = Parent.pattern_table_entries),
211 "Indexing policy of the pattern table")
212 pattern_table_replacement_policy = Param.BaseReplacementPolicy(LRURP(),
213 "Replacement policy of the pattern table")
214
215 prefetch_confidence_threshold = Param.Float(0.5,
216 "Minimum confidence to issue prefetches")
217 lookahead_confidence_threshold = Param.Float(0.75,
218 "Minimum confidence to continue exploring lookahead entries")
219
220class SignaturePathPrefetcherV2(SignaturePathPrefetcher):
221 type = 'SignaturePathPrefetcherV2'
222 cxx_class = 'SignaturePathPrefetcherV2'
223 cxx_header = "mem/cache/prefetch/signature_path_v2.hh"
224
225 signature_table_entries = "256"
226 signature_table_assoc = 1
227 pattern_table_entries = "512"
228 pattern_table_assoc = 1
229 max_counter_value = 15
230 prefetch_confidence_threshold = 0.25
231 lookahead_confidence_threshold = 0.25
232
233 global_history_register_entries = Param.MemorySize("8",
234 "Number of entries of global history register")
235 global_history_register_indexing_policy = Param.BaseIndexingPolicy(
236 SetAssociative(entry_size = 1,
237 assoc = Parent.global_history_register_entries,
238 size = Parent.global_history_register_entries),
239 "Indexing policy of the global history register")
240 global_history_register_replacement_policy = Param.BaseReplacementPolicy(
241 LRURP(), "Replacement policy of the global history register")
242
243class AccessMapPatternMatching(ClockedObject):
244 type = 'AccessMapPatternMatching'
245 cxx_class = 'AccessMapPatternMatching'
246 cxx_header = "mem/cache/prefetch/access_map_pattern_matching.hh"
247
248 block_size = Param.Unsigned(Parent.block_size,
249 "Cacheline size used by the prefetcher using this object")
250
251 limit_stride = Param.Unsigned(0,
252 "Limit the strides checked up to -X/X, if 0, disable the limit")
253 start_degree = Param.Unsigned(4,
254 "Initial degree (Maximum number of prefetches generated")
255 hot_zone_size = Param.MemorySize("2kB", "Memory covered by a hot zone")
256 access_map_table_entries = Param.MemorySize("256",
257 "Number of entries in the access map table")
258 access_map_table_assoc = Param.Unsigned(8,
259 "Associativity of the access map table")
260 access_map_table_indexing_policy = Param.BaseIndexingPolicy(
261 SetAssociative(entry_size = 1, assoc = Parent.access_map_table_assoc,
262 size = Parent.access_map_table_entries),
263 "Indexing policy of the access map table")
264 access_map_table_replacement_policy = Param.BaseReplacementPolicy(LRURP(),
265 "Replacement policy of the access map table")
266 high_coverage_threshold = Param.Float(0.25,
267 "A prefetch coverage factor bigger than this is considered high")
268 low_coverage_threshold = Param.Float(0.125,
269 "A prefetch coverage factor smaller than this is considered low")
270 high_accuracy_threshold = Param.Float(0.5,
271 "A prefetch accuracy factor bigger than this is considered high")
272 low_accuracy_threshold = Param.Float(0.25,
273 "A prefetch accuracy factor smaller than this is considered low")
274 high_cache_hit_threshold = Param.Float(0.875,
275 "A cache hit ratio bigger than this is considered high")
276 low_cache_hit_threshold = Param.Float(0.75,
277 "A cache hit ratio smaller than this is considered low")
278 epoch_cycles = Param.Cycles(256000, "Cycles in an epoch period")
279 offchip_memory_latency = Param.Latency("30ns",
280 "Memory latency used to compute the required memory bandwidth")
281
282class AMPMPrefetcher(QueuedPrefetcher):
283 type = 'AMPMPrefetcher'
284 cxx_class = 'AMPMPrefetcher'
285 cxx_header = "mem/cache/prefetch/access_map_pattern_matching.hh"
286 ampm = Param.AccessMapPatternMatching( AccessMapPatternMatching(),
287 "Access Map Pattern Matching object")
288
289class DeltaCorrelatingPredictionTables(SimObject):
290 type = 'DeltaCorrelatingPredictionTables'
291 cxx_class = 'DeltaCorrelatingPredictionTables'
292 cxx_header = "mem/cache/prefetch/delta_correlating_prediction_tables.hh"
293 deltas_per_entry = Param.Unsigned(20,
294 "Number of deltas stored in each table entry")
295 delta_bits = Param.Unsigned(12, "Bits per delta")
296 delta_mask_bits = Param.Unsigned(8,
297 "Lower bits to mask when comparing deltas")
298 table_entries = Param.MemorySize("128",
299 "Number of entries in the table")
300 table_assoc = Param.Unsigned(128,
301 "Associativity of the table")
302 table_indexing_policy = Param.BaseIndexingPolicy(
303 SetAssociative(entry_size = 1, assoc = Parent.table_assoc,
304 size = Parent.table_entries),
305 "Indexing policy of the table")
306 table_replacement_policy = Param.BaseReplacementPolicy(LRURP(),
307 "Replacement policy of the table")
308
309class DCPTPrefetcher(QueuedPrefetcher):
310 type = 'DCPTPrefetcher'
311 cxx_class = 'DCPTPrefetcher'
312 cxx_header = "mem/cache/prefetch/delta_correlating_prediction_tables.hh"
313 dcpt = Param.DeltaCorrelatingPredictionTables(
314 DeltaCorrelatingPredictionTables(),
315 "Delta Correlating Prediction Tables object")
316
317class IrregularStreamBufferPrefetcher(QueuedPrefetcher):
318 type = "IrregularStreamBufferPrefetcher"
319 cxx_class = "IrregularStreamBufferPrefetcher"
320 cxx_header = "mem/cache/prefetch/irregular_stream_buffer.hh"
321
322 max_counter_value = Param.Unsigned(3,
323 "Maximum value of the confidence counter")
324 chunk_size = Param.Unsigned(256,
325 "Maximum number of addresses in a temporal stream")
326 degree = Param.Unsigned(4, "Number of prefetches to generate")
327 training_unit_assoc = Param.Unsigned(128,
328 "Associativity of the training unit")
329 training_unit_entries = Param.MemorySize("128",
330 "Number of entries of the training unit")
331 training_unit_indexing_policy = Param.BaseIndexingPolicy(
332 SetAssociative(entry_size = 1, assoc = Parent.training_unit_assoc,
333 size = Parent.training_unit_entries),
334 "Indexing policy of the training unit")
335 training_unit_replacement_policy = Param.BaseReplacementPolicy(LRURP(),
336 "Replacement policy of the training unit")
337
338 prefetch_candidates_per_entry = Param.Unsigned(16,
339 "Number of prefetch candidates stored in a SP-AMC entry")
340 address_map_cache_assoc = Param.Unsigned(128,
341 "Associativity of the PS/SP AMCs")
342 address_map_cache_entries = Param.MemorySize("128",
343 "Number of entries of the PS/SP AMCs")
344 ps_address_map_cache_indexing_policy = Param.BaseIndexingPolicy(
345 SetAssociative(entry_size = 1,
346 assoc = Parent.address_map_cache_assoc,
347 size = Parent.address_map_cache_entries),
348 "Indexing policy of the Physical-to-Structural Address Map Cache")
349 ps_address_map_cache_replacement_policy = Param.BaseReplacementPolicy(
350 LRURP(),
351 "Replacement policy of the Physical-to-Structural Address Map Cache")
352 sp_address_map_cache_indexing_policy = Param.BaseIndexingPolicy(
353 SetAssociative(entry_size = 1,
354 assoc = Parent.address_map_cache_assoc,
355 size = Parent.address_map_cache_entries),
356 "Indexing policy of the Structural-to-Physical Address Mao Cache")
357 sp_address_map_cache_replacement_policy = Param.BaseReplacementPolicy(
358 LRURP(),
359 "Replacement policy of the Structural-to-Physical Address Map Cache")
360
361class SlimAccessMapPatternMatching(AccessMapPatternMatching):
362 start_degree = 2
363 limit_stride = 4
364
365class SlimDeltaCorrelatingPredictionTables(DeltaCorrelatingPredictionTables):
366 table_entries = "256"
367 table_assoc = 256
368 deltas_per_entry = 9
369
370class SlimAMPMPrefetcher(QueuedPrefetcher):
371 type = 'SlimAMPMPrefetcher'
372 cxx_class = 'SlimAMPMPrefetcher'
373 cxx_header = "mem/cache/prefetch/slim_ampm.hh"
374
375 ampm = Param.AccessMapPatternMatching(SlimAccessMapPatternMatching(),
376 "Access Map Pattern Matching object")
377 dcpt = Param.DeltaCorrelatingPredictionTables(
378 SlimDeltaCorrelatingPredictionTables(),
379 "Delta Correlating Prediction Tables object")
380
381class BOPPrefetcher(QueuedPrefetcher):
382 type = "BOPPrefetcher"
383 cxx_class = "BOPPrefetcher"
384 cxx_header = "mem/cache/prefetch/bop.hh"
385 score_max = Param.Unsigned(31, "Max. score to update the best offset")
386 round_max = Param.Unsigned(100, "Max. round to update the best offset")
387 bad_score = Param.Unsigned(10, "Score at which the HWP is disabled")
388 rr_size = Param.Unsigned(64, "Number of entries of each RR bank")
389 tag_bits = Param.Unsigned(12, "Bits used to store the tag")
390 offset_list_size = Param.Unsigned(46,
391 "Number of entries in the offsets list")
392 negative_offsets_enable = Param.Bool(True,
393 "Initialize the offsets list also with negative values \
394 (i.e. the table will have half of the entries with positive \
395 offsets and the other half with negative ones)")
396 delay_queue_enable = Param.Bool(True, "Enable the delay queue")
397 delay_queue_size = Param.Unsigned(15,
398 "Number of entries in the delay queue")
399 delay_queue_cycles = Param.Cycles(60,
400 "Cycles to delay a write in the left RR table from the delay \
401 queue")
402
403class SBOOEPrefetcher(QueuedPrefetcher):
404 type = 'SBOOEPrefetcher'
405 cxx_class = 'SBOOEPrefetcher'
406 cxx_header = "mem/cache/prefetch/sbooe.hh"
407 latency_buffer_size = Param.Int(32, "Entries in the latency buffer")
408 sequential_prefetchers = Param.Int(9, "Number of sequential prefetchers")
409 sandbox_entries = Param.Int(1024, "Size of the address buffer")
410 score_threshold_pct = Param.Percent(25, "Min. threshold to issue a \
411 prefetch. The value is the percentage of sandbox entries to use")
412
413class STeMSPrefetcher(QueuedPrefetcher):
414 type = "STeMSPrefetcher"
415 cxx_class = "STeMSPrefetcher"
416 cxx_header = "mem/cache/prefetch/spatio_temporal_memory_streaming.hh"
417
418 spatial_region_size = Param.MemorySize("2kB",
419 "Memory covered by a hot zone")
420 active_generation_table_entries = Param.MemorySize("64",
421 "Number of entries in the active generation table")
422 active_generation_table_assoc = Param.Unsigned(64,
423 "Associativity of the active generation table")
424 active_generation_table_indexing_policy = Param.BaseIndexingPolicy(
425 SetAssociative(entry_size = 1,
426 assoc = Parent.active_generation_table_assoc,
427 size = Parent.active_generation_table_entries),
428 "Indexing policy of the active generation table")
429 active_generation_table_replacement_policy = Param.BaseReplacementPolicy(
430 LRURP(), "Replacement policy of the active generation table")
431
432 pattern_sequence_table_entries = Param.MemorySize("16384",
433 "Number of entries in the pattern sequence table")
434 pattern_sequence_table_assoc = Param.Unsigned(16384,
435 "Associativity of the pattern sequence table")
436 pattern_sequence_table_indexing_policy = Param.BaseIndexingPolicy(
437 SetAssociative(entry_size = 1,
438 assoc = Parent.pattern_sequence_table_assoc,
439 size = Parent.pattern_sequence_table_entries),
440 "Indexing policy of the pattern sequence table")
441 pattern_sequence_table_replacement_policy = Param.BaseReplacementPolicy(
442 LRURP(), "Replacement policy of the pattern sequence table")
443
444 region_miss_order_buffer_entries = Param.Unsigned(131072,
445 "Number of entries of the Region Miss Order Buffer")
446 reconstruction_entries = Param.Unsigned(256,
447 "Number of reconstruction entries")
448
449class HWPProbeEventRetiredInsts(HWPProbeEvent):
450 def register(self):
451 if self.obj:
452 for name in self.names:
453 self.prefetcher.getCCObject().addEventProbeRetiredInsts(
454 self.obj.getCCObject(), name)
455
456class PIFPrefetcher(QueuedPrefetcher):
457 type = 'PIFPrefetcher'
458 cxx_class = 'PIFPrefetcher'
459 cxx_header = "mem/cache/prefetch/pif.hh"
460 cxx_exports = [
461 PyBindMethod("addEventProbeRetiredInsts"),
462 ]
463
464 prec_spatial_region_bits = Param.Unsigned(2,
465 "Number of preceding addresses in the spatial region")
466 succ_spatial_region_bits = Param.Unsigned(8,
467 "Number of subsequent addresses in the spatial region")
468 compactor_entries = Param.Unsigned(2, "Entries in the temp. compactor")
469 stream_address_buffer_entries = Param.Unsigned(7, "Entries in the SAB")
470 history_buffer_size = Param.Unsigned(16, "Entries in the history buffer")
471
472 index_entries = Param.MemorySize("64",
473 "Number of entries in the index")
474 index_assoc = Param.Unsigned(64,
475 "Associativity of the index")
476 index_indexing_policy = Param.BaseIndexingPolicy(
477 SetAssociative(entry_size = 1, assoc = Parent.index_assoc,
478 size = Parent.index_entries),
479 "Indexing policy of the index")
480 index_replacement_policy = Param.BaseReplacementPolicy(LRURP(),
481 "Replacement policy of the index")
482
483 def listenFromProbeRetiredInstructions(self, simObj):
484 if not isinstance(simObj, BaseCPU):
485 raise TypeError("argument must be of BaseCPU type")
486 self.addEvent(HWPProbeEventRetiredInsts(self, simObj,"RetiredInstsPC"))