1/*
2 * Copyright (c) 2013-2016 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 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions are
16 * met: redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer;
18 * redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution;
21 * neither the name of the copyright holders nor the names of its
22 * contributors may be used to endorse or promote products derived from
23 * this software without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
26 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
27 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
28 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
29 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
30 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
31 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
35 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 *
37 * Authors: Stephan Diestelhorst
38 */
39
40/**
41 * @file
42 * Implementation of a snoop filter.
43 */
44
45#include "base/misc.hh"
46#include "base/trace.hh"
47#include "debug/SnoopFilter.hh"
48#include "mem/snoop_filter.hh"
49#include "sim/system.hh"
50
51void
52SnoopFilter::eraseIfNullEntry(SnoopFilterCache::iterator& sf_it)
53{
54 SnoopItem& sf_item = sf_it->second;
55 if (!(sf_item.requested | sf_item.holder)) {
56 cachedLocations.erase(sf_it);
57 DPRINTF(SnoopFilter, "%s: Removed SF entry.\n",
58 __func__);
59 }
60}
61
62std::pair<SnoopFilter::SnoopList, Cycles>
63SnoopFilter::lookupRequest(const Packet* cpkt, const SlavePort& slave_port)
64{
65 DPRINTF(SnoopFilter, "%s: packet src %s addr 0x%x cmd %s\n",
66 __func__, slave_port.name(), cpkt->getAddr(), cpkt->cmdString());
67
68 // check if the packet came from a cache
69 bool allocate = !cpkt->req->isUncacheable() && slave_port.isSnooping() &&
70 cpkt->fromCache();
71 Addr line_addr = cpkt->getBlockAddr(linesize);
| 1/*
2 * Copyright (c) 2013-2016 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 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions are
16 * met: redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer;
18 * redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution;
21 * neither the name of the copyright holders nor the names of its
22 * contributors may be used to endorse or promote products derived from
23 * this software without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
26 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
27 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
28 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
29 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
30 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
31 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
35 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 *
37 * Authors: Stephan Diestelhorst
38 */
39
40/**
41 * @file
42 * Implementation of a snoop filter.
43 */
44
45#include "base/misc.hh"
46#include "base/trace.hh"
47#include "debug/SnoopFilter.hh"
48#include "mem/snoop_filter.hh"
49#include "sim/system.hh"
50
51void
52SnoopFilter::eraseIfNullEntry(SnoopFilterCache::iterator& sf_it)
53{
54 SnoopItem& sf_item = sf_it->second;
55 if (!(sf_item.requested | sf_item.holder)) {
56 cachedLocations.erase(sf_it);
57 DPRINTF(SnoopFilter, "%s: Removed SF entry.\n",
58 __func__);
59 }
60}
61
62std::pair<SnoopFilter::SnoopList, Cycles>
63SnoopFilter::lookupRequest(const Packet* cpkt, const SlavePort& slave_port)
64{
65 DPRINTF(SnoopFilter, "%s: packet src %s addr 0x%x cmd %s\n",
66 __func__, slave_port.name(), cpkt->getAddr(), cpkt->cmdString());
67
68 // check if the packet came from a cache
69 bool allocate = !cpkt->req->isUncacheable() && slave_port.isSnooping() &&
70 cpkt->fromCache();
71 Addr line_addr = cpkt->getBlockAddr(linesize);
|
| 72 if (cpkt->isSecure()) {
73 line_addr |= LineSecure;
74 }
|
72 SnoopMask req_port = portToMask(slave_port);
73 reqLookupResult = cachedLocations.find(line_addr);
74 bool is_hit = (reqLookupResult != cachedLocations.end());
75
76 // If the snoop filter has no entry, and we should not allocate,
77 // do not create a new snoop filter entry, simply return a NULL
78 // portlist.
79 if (!is_hit && !allocate)
80 return snoopDown(lookupLatency);
81
82 // If no hit in snoop filter create a new element and update iterator
83 if (!is_hit)
84 reqLookupResult = cachedLocations.emplace(line_addr, SnoopItem()).first;
85 SnoopItem& sf_item = reqLookupResult->second;
86 SnoopMask interested = sf_item.holder | sf_item.requested;
87
88 // Store unmodified value of snoop filter item in temp storage in
89 // case we need to revert because of a send retry in
90 // updateRequest.
91 retryItem = sf_item;
92
93 totRequests++;
94 if (is_hit) {
95 // Single bit set -> value is a power of two
96 if (isPow2(interested))
97 hitSingleRequests++;
98 else
99 hitMultiRequests++;
100 }
101
102 DPRINTF(SnoopFilter, "%s: SF value %x.%x\n",
103 __func__, sf_item.requested, sf_item.holder);
104
105 // If we are not allocating, we are done
106 if (!allocate)
107 return snoopSelected(maskToPortList(interested & ~req_port),
108 lookupLatency);
109
110 if (cpkt->needsResponse()) {
111 if (!cpkt->cacheResponding()) {
112 // Max one request per address per port
113 panic_if(sf_item.requested & req_port, "double request :( " \
114 "SF value %x.%x\n", sf_item.requested, sf_item.holder);
115
116 // Mark in-flight requests to distinguish later on
117 sf_item.requested |= req_port;
118 DPRINTF(SnoopFilter, "%s: new SF value %x.%x\n",
119 __func__, sf_item.requested, sf_item.holder);
120 } else {
121 // NOTE: The memInhibit might have been asserted by a cache closer
122 // to the CPU, already -> the response will not be seen by this
123 // filter -> we do not need to keep the in-flight request, but make
124 // sure that we know that that cluster has a copy
125 panic_if(!(sf_item.holder & req_port), "Need to hold the value!");
126 DPRINTF(SnoopFilter,
127 "%s: not marking request. SF value %x.%x\n",
128 __func__, sf_item.requested, sf_item.holder);
129 }
130 } else { // if (!cpkt->needsResponse())
131 assert(cpkt->isEviction());
132 // make sure that the sender actually had the line
133 panic_if(!(sf_item.holder & req_port), "requester %x is not a " \
134 "holder :( SF value %x.%x\n", req_port,
135 sf_item.requested, sf_item.holder);
136 // CleanEvicts and Writebacks -> the sender and all caches above
137 // it may not have the line anymore.
138 if (!cpkt->isBlockCached()) {
139 sf_item.holder &= ~req_port;
140 DPRINTF(SnoopFilter, "%s: new SF value %x.%x\n",
141 __func__, sf_item.requested, sf_item.holder);
142 }
143 }
144
145 return snoopSelected(maskToPortList(interested & ~req_port), lookupLatency);
146}
147
148void
| 75 SnoopMask req_port = portToMask(slave_port);
76 reqLookupResult = cachedLocations.find(line_addr);
77 bool is_hit = (reqLookupResult != cachedLocations.end());
78
79 // If the snoop filter has no entry, and we should not allocate,
80 // do not create a new snoop filter entry, simply return a NULL
81 // portlist.
82 if (!is_hit && !allocate)
83 return snoopDown(lookupLatency);
84
85 // If no hit in snoop filter create a new element and update iterator
86 if (!is_hit)
87 reqLookupResult = cachedLocations.emplace(line_addr, SnoopItem()).first;
88 SnoopItem& sf_item = reqLookupResult->second;
89 SnoopMask interested = sf_item.holder | sf_item.requested;
90
91 // Store unmodified value of snoop filter item in temp storage in
92 // case we need to revert because of a send retry in
93 // updateRequest.
94 retryItem = sf_item;
95
96 totRequests++;
97 if (is_hit) {
98 // Single bit set -> value is a power of two
99 if (isPow2(interested))
100 hitSingleRequests++;
101 else
102 hitMultiRequests++;
103 }
104
105 DPRINTF(SnoopFilter, "%s: SF value %x.%x\n",
106 __func__, sf_item.requested, sf_item.holder);
107
108 // If we are not allocating, we are done
109 if (!allocate)
110 return snoopSelected(maskToPortList(interested & ~req_port),
111 lookupLatency);
112
113 if (cpkt->needsResponse()) {
114 if (!cpkt->cacheResponding()) {
115 // Max one request per address per port
116 panic_if(sf_item.requested & req_port, "double request :( " \
117 "SF value %x.%x\n", sf_item.requested, sf_item.holder);
118
119 // Mark in-flight requests to distinguish later on
120 sf_item.requested |= req_port;
121 DPRINTF(SnoopFilter, "%s: new SF value %x.%x\n",
122 __func__, sf_item.requested, sf_item.holder);
123 } else {
124 // NOTE: The memInhibit might have been asserted by a cache closer
125 // to the CPU, already -> the response will not be seen by this
126 // filter -> we do not need to keep the in-flight request, but make
127 // sure that we know that that cluster has a copy
128 panic_if(!(sf_item.holder & req_port), "Need to hold the value!");
129 DPRINTF(SnoopFilter,
130 "%s: not marking request. SF value %x.%x\n",
131 __func__, sf_item.requested, sf_item.holder);
132 }
133 } else { // if (!cpkt->needsResponse())
134 assert(cpkt->isEviction());
135 // make sure that the sender actually had the line
136 panic_if(!(sf_item.holder & req_port), "requester %x is not a " \
137 "holder :( SF value %x.%x\n", req_port,
138 sf_item.requested, sf_item.holder);
139 // CleanEvicts and Writebacks -> the sender and all caches above
140 // it may not have the line anymore.
141 if (!cpkt->isBlockCached()) {
142 sf_item.holder &= ~req_port;
143 DPRINTF(SnoopFilter, "%s: new SF value %x.%x\n",
144 __func__, sf_item.requested, sf_item.holder);
145 }
146 }
147
148 return snoopSelected(maskToPortList(interested & ~req_port), lookupLatency);
149}
150
151void
|
149SnoopFilter::finishRequest(bool will_retry, const Addr addr)
| 152SnoopFilter::finishRequest(bool will_retry, Addr addr, bool is_secure)
|
150{
151 if (reqLookupResult != cachedLocations.end()) {
152 // since we rely on the caller, do a basic check to ensure
153 // that finishRequest is being called following lookupRequest
| 153{
154 if (reqLookupResult != cachedLocations.end()) {
155 // since we rely on the caller, do a basic check to ensure
156 // that finishRequest is being called following lookupRequest
|
154 assert(reqLookupResult->first == (addr & ~(Addr(linesize - 1))));
| 157 Addr line_addr = (addr & ~(Addr(linesize - 1)));
158 if (is_secure) {
159 line_addr |= LineSecure;
160 }
161 assert(reqLookupResult->first == line_addr);
|
155 if (will_retry) {
156 // Undo any changes made in lookupRequest to the snoop filter
157 // entry if the request will come again. retryItem holds
158 // the previous value of the snoopfilter entry.
159 reqLookupResult->second = retryItem;
160
161 DPRINTF(SnoopFilter, "%s: restored SF value %x.%x\n",
162 __func__, retryItem.requested, retryItem.holder);
163 }
164
165 eraseIfNullEntry(reqLookupResult);
166 }
167}
168
169std::pair<SnoopFilter::SnoopList, Cycles>
170SnoopFilter::lookupSnoop(const Packet* cpkt)
171{
172 DPRINTF(SnoopFilter, "%s: packet addr 0x%x cmd %s\n",
173 __func__, cpkt->getAddr(), cpkt->cmdString());
174
175 assert(cpkt->isRequest());
176
177 Addr line_addr = cpkt->getBlockAddr(linesize);
| 162 if (will_retry) {
163 // Undo any changes made in lookupRequest to the snoop filter
164 // entry if the request will come again. retryItem holds
165 // the previous value of the snoopfilter entry.
166 reqLookupResult->second = retryItem;
167
168 DPRINTF(SnoopFilter, "%s: restored SF value %x.%x\n",
169 __func__, retryItem.requested, retryItem.holder);
170 }
171
172 eraseIfNullEntry(reqLookupResult);
173 }
174}
175
176std::pair<SnoopFilter::SnoopList, Cycles>
177SnoopFilter::lookupSnoop(const Packet* cpkt)
178{
179 DPRINTF(SnoopFilter, "%s: packet addr 0x%x cmd %s\n",
180 __func__, cpkt->getAddr(), cpkt->cmdString());
181
182 assert(cpkt->isRequest());
183
184 Addr line_addr = cpkt->getBlockAddr(linesize);
|
| 185 if (cpkt->isSecure()) {
186 line_addr |= LineSecure;
187 }
|
178 auto sf_it = cachedLocations.find(line_addr);
179 bool is_hit = (sf_it != cachedLocations.end());
180
181 panic_if(!is_hit && (cachedLocations.size() >= maxEntryCount),
182 "snoop filter exceeded capacity of %d cache blocks\n",
183 maxEntryCount);
184
185 // If the snoop filter has no entry, simply return a NULL
186 // portlist, there is no point creating an entry only to remove it
187 // later
188 if (!is_hit)
189 return snoopDown(lookupLatency);
190
191 SnoopItem& sf_item = sf_it->second;
192
193 DPRINTF(SnoopFilter, "%s: old SF value %x.%x\n",
194 __func__, sf_item.requested, sf_item.holder);
195
196 SnoopMask interested = (sf_item.holder | sf_item.requested);
197
198 totSnoops++;
199 // Single bit set -> value is a power of two
200 if (isPow2(interested))
201 hitSingleSnoops++;
202 else
203 hitMultiSnoops++;
204
205 // ReadEx and Writes require both invalidation and exlusivity, while reads
206 // require neither. Writebacks on the other hand require exclusivity but
207 // not the invalidation. Previously Writebacks did not generate upward
208 // snoops so this was never an aissue. Now that Writebacks generate snoops
209 // we need to special case for Writebacks.
210 assert(cpkt->isWriteback() || cpkt->req->isUncacheable() ||
211 (cpkt->isInvalidate() == cpkt->needsWritable()));
212 if (cpkt->isInvalidate() && !sf_item.requested) {
213 // Early clear of the holder, if no other request is currently going on
214 // @todo: This should possibly be updated even though we do not filter
215 // upward snoops
216 sf_item.holder = 0;
217 }
218
219 eraseIfNullEntry(sf_it);
220 DPRINTF(SnoopFilter, "%s: new SF value %x.%x interest: %x \n",
221 __func__, sf_item.requested, sf_item.holder, interested);
222
223 return snoopSelected(maskToPortList(interested), lookupLatency);
224}
225
226void
227SnoopFilter::updateSnoopResponse(const Packet* cpkt,
228 const SlavePort& rsp_port,
229 const SlavePort& req_port)
230{
231 DPRINTF(SnoopFilter, "%s: packet rsp %s req %s addr 0x%x cmd %s\n",
232 __func__, rsp_port.name(), req_port.name(), cpkt->getAddr(),
233 cpkt->cmdString());
234
235 assert(cpkt->isResponse());
236 assert(cpkt->cacheResponding());
237
238 // if this snoop response is due to an uncacheable request, or is
239 // being turned into a normal response, there is nothing more to
240 // do
241 if (cpkt->req->isUncacheable() || !req_port.isSnooping()) {
242 return;
243 }
244
245 Addr line_addr = cpkt->getBlockAddr(linesize);
| 188 auto sf_it = cachedLocations.find(line_addr);
189 bool is_hit = (sf_it != cachedLocations.end());
190
191 panic_if(!is_hit && (cachedLocations.size() >= maxEntryCount),
192 "snoop filter exceeded capacity of %d cache blocks\n",
193 maxEntryCount);
194
195 // If the snoop filter has no entry, simply return a NULL
196 // portlist, there is no point creating an entry only to remove it
197 // later
198 if (!is_hit)
199 return snoopDown(lookupLatency);
200
201 SnoopItem& sf_item = sf_it->second;
202
203 DPRINTF(SnoopFilter, "%s: old SF value %x.%x\n",
204 __func__, sf_item.requested, sf_item.holder);
205
206 SnoopMask interested = (sf_item.holder | sf_item.requested);
207
208 totSnoops++;
209 // Single bit set -> value is a power of two
210 if (isPow2(interested))
211 hitSingleSnoops++;
212 else
213 hitMultiSnoops++;
214
215 // ReadEx and Writes require both invalidation and exlusivity, while reads
216 // require neither. Writebacks on the other hand require exclusivity but
217 // not the invalidation. Previously Writebacks did not generate upward
218 // snoops so this was never an aissue. Now that Writebacks generate snoops
219 // we need to special case for Writebacks.
220 assert(cpkt->isWriteback() || cpkt->req->isUncacheable() ||
221 (cpkt->isInvalidate() == cpkt->needsWritable()));
222 if (cpkt->isInvalidate() && !sf_item.requested) {
223 // Early clear of the holder, if no other request is currently going on
224 // @todo: This should possibly be updated even though we do not filter
225 // upward snoops
226 sf_item.holder = 0;
227 }
228
229 eraseIfNullEntry(sf_it);
230 DPRINTF(SnoopFilter, "%s: new SF value %x.%x interest: %x \n",
231 __func__, sf_item.requested, sf_item.holder, interested);
232
233 return snoopSelected(maskToPortList(interested), lookupLatency);
234}
235
236void
237SnoopFilter::updateSnoopResponse(const Packet* cpkt,
238 const SlavePort& rsp_port,
239 const SlavePort& req_port)
240{
241 DPRINTF(SnoopFilter, "%s: packet rsp %s req %s addr 0x%x cmd %s\n",
242 __func__, rsp_port.name(), req_port.name(), cpkt->getAddr(),
243 cpkt->cmdString());
244
245 assert(cpkt->isResponse());
246 assert(cpkt->cacheResponding());
247
248 // if this snoop response is due to an uncacheable request, or is
249 // being turned into a normal response, there is nothing more to
250 // do
251 if (cpkt->req->isUncacheable() || !req_port.isSnooping()) {
252 return;
253 }
254
255 Addr line_addr = cpkt->getBlockAddr(linesize);
|
| 256 if (cpkt->isSecure()) {
257 line_addr |= LineSecure;
258 }
|
246 SnoopMask rsp_mask = portToMask(rsp_port);
247 SnoopMask req_mask = portToMask(req_port);
248 SnoopItem& sf_item = cachedLocations[line_addr];
249
250 DPRINTF(SnoopFilter, "%s: old SF value %x.%x\n",
251 __func__, sf_item.requested, sf_item.holder);
252
253 // The source should have the line
254 panic_if(!(sf_item.holder & rsp_mask), "SF value %x.%x does not have "\
255 "the line\n", sf_item.requested, sf_item.holder);
256
257 // The destination should have had a request in
258 panic_if(!(sf_item.requested & req_mask), "SF value %x.%x missing "\
259 "the original request\n", sf_item.requested, sf_item.holder);
260
261 // If the snoop response has no sharers the line is passed in
262 // Modified state, and we know that there are no other copies, or
263 // they will all be invalidated imminently
264 if (!cpkt->hasSharers()) {
265 DPRINTF(SnoopFilter,
266 "%s: dropping %x because non-shared snoop "
267 "response SF val: %x.%x\n", __func__, rsp_mask,
268 sf_item.requested, sf_item.holder);
269 sf_item.holder = 0;
270 }
271 assert(!cpkt->isWriteback());
272 // @todo Deal with invalidating responses
273 sf_item.holder |= req_mask;
274 sf_item.requested &= ~req_mask;
275 assert(sf_item.requested | sf_item.holder);
276 DPRINTF(SnoopFilter, "%s: new SF value %x.%x\n",
277 __func__, sf_item.requested, sf_item.holder);
278}
279
280void
281SnoopFilter::updateSnoopForward(const Packet* cpkt,
282 const SlavePort& rsp_port, const MasterPort& req_port)
283{
284 DPRINTF(SnoopFilter, "%s: packet rsp %s req %s addr 0x%x cmd %s\n",
285 __func__, rsp_port.name(), req_port.name(), cpkt->getAddr(),
286 cpkt->cmdString());
287
288 assert(cpkt->isResponse());
289 assert(cpkt->cacheResponding());
290
291 Addr line_addr = cpkt->getBlockAddr(linesize);
| 259 SnoopMask rsp_mask = portToMask(rsp_port);
260 SnoopMask req_mask = portToMask(req_port);
261 SnoopItem& sf_item = cachedLocations[line_addr];
262
263 DPRINTF(SnoopFilter, "%s: old SF value %x.%x\n",
264 __func__, sf_item.requested, sf_item.holder);
265
266 // The source should have the line
267 panic_if(!(sf_item.holder & rsp_mask), "SF value %x.%x does not have "\
268 "the line\n", sf_item.requested, sf_item.holder);
269
270 // The destination should have had a request in
271 panic_if(!(sf_item.requested & req_mask), "SF value %x.%x missing "\
272 "the original request\n", sf_item.requested, sf_item.holder);
273
274 // If the snoop response has no sharers the line is passed in
275 // Modified state, and we know that there are no other copies, or
276 // they will all be invalidated imminently
277 if (!cpkt->hasSharers()) {
278 DPRINTF(SnoopFilter,
279 "%s: dropping %x because non-shared snoop "
280 "response SF val: %x.%x\n", __func__, rsp_mask,
281 sf_item.requested, sf_item.holder);
282 sf_item.holder = 0;
283 }
284 assert(!cpkt->isWriteback());
285 // @todo Deal with invalidating responses
286 sf_item.holder |= req_mask;
287 sf_item.requested &= ~req_mask;
288 assert(sf_item.requested | sf_item.holder);
289 DPRINTF(SnoopFilter, "%s: new SF value %x.%x\n",
290 __func__, sf_item.requested, sf_item.holder);
291}
292
293void
294SnoopFilter::updateSnoopForward(const Packet* cpkt,
295 const SlavePort& rsp_port, const MasterPort& req_port)
296{
297 DPRINTF(SnoopFilter, "%s: packet rsp %s req %s addr 0x%x cmd %s\n",
298 __func__, rsp_port.name(), req_port.name(), cpkt->getAddr(),
299 cpkt->cmdString());
300
301 assert(cpkt->isResponse());
302 assert(cpkt->cacheResponding());
303
304 Addr line_addr = cpkt->getBlockAddr(linesize);
|
| 305 if (cpkt->isSecure()) {
306 line_addr |= LineSecure;
307 }
|
292 auto sf_it = cachedLocations.find(line_addr);
293 bool is_hit = sf_it != cachedLocations.end();
294
295 // Nothing to do if it is not a hit
296 if (!is_hit)
297 return;
298
299 SnoopItem& sf_item = sf_it->second;
300
301 DPRINTF(SnoopFilter, "%s: old SF value %x.%x\n",
302 __func__, sf_item.requested, sf_item.holder);
303
304 // If the snoop response has no sharers the line is passed in
305 // Modified state, and we know that there are no other copies, or
306 // they will all be invalidated imminently
307 if (!cpkt->hasSharers()) {
308 sf_item.holder = 0;
309 }
310 DPRINTF(SnoopFilter, "%s: new SF value %x.%x\n",
311 __func__, sf_item.requested, sf_item.holder);
312 eraseIfNullEntry(sf_it);
313
314}
315
316void
317SnoopFilter::updateResponse(const Packet* cpkt, const SlavePort& slave_port)
318{
319 DPRINTF(SnoopFilter, "%s: packet src %s addr 0x%x cmd %s\n",
320 __func__, slave_port.name(), cpkt->getAddr(), cpkt->cmdString());
321
322 assert(cpkt->isResponse());
323
324 // we only allocate if the packet actually came from a cache, but
325 // start by checking if the port is snooping
326 if (cpkt->req->isUncacheable() || !slave_port.isSnooping())
327 return;
328
329 // next check if we actually allocated an entry
330 Addr line_addr = cpkt->getBlockAddr(linesize);
| 308 auto sf_it = cachedLocations.find(line_addr);
309 bool is_hit = sf_it != cachedLocations.end();
310
311 // Nothing to do if it is not a hit
312 if (!is_hit)
313 return;
314
315 SnoopItem& sf_item = sf_it->second;
316
317 DPRINTF(SnoopFilter, "%s: old SF value %x.%x\n",
318 __func__, sf_item.requested, sf_item.holder);
319
320 // If the snoop response has no sharers the line is passed in
321 // Modified state, and we know that there are no other copies, or
322 // they will all be invalidated imminently
323 if (!cpkt->hasSharers()) {
324 sf_item.holder = 0;
325 }
326 DPRINTF(SnoopFilter, "%s: new SF value %x.%x\n",
327 __func__, sf_item.requested, sf_item.holder);
328 eraseIfNullEntry(sf_it);
329
330}
331
332void
333SnoopFilter::updateResponse(const Packet* cpkt, const SlavePort& slave_port)
334{
335 DPRINTF(SnoopFilter, "%s: packet src %s addr 0x%x cmd %s\n",
336 __func__, slave_port.name(), cpkt->getAddr(), cpkt->cmdString());
337
338 assert(cpkt->isResponse());
339
340 // we only allocate if the packet actually came from a cache, but
341 // start by checking if the port is snooping
342 if (cpkt->req->isUncacheable() || !slave_port.isSnooping())
343 return;
344
345 // next check if we actually allocated an entry
346 Addr line_addr = cpkt->getBlockAddr(linesize);
|
| 347 if (cpkt->isSecure()) {
348 line_addr |= LineSecure;
349 }
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331 auto sf_it = cachedLocations.find(line_addr);
332 if (sf_it == cachedLocations.end())
333 return;
334
335 SnoopMask slave_mask = portToMask(slave_port);
336 SnoopItem& sf_item = sf_it->second;
337
338 DPRINTF(SnoopFilter, "%s: old SF value %x.%x\n",
339 __func__, sf_item.requested, sf_item.holder);
340
341 // Make sure we have seen the actual request, too
342 panic_if(!(sf_item.requested & slave_mask), "SF value %x.%x missing "\
343 "request bit\n", sf_item.requested, sf_item.holder);
344
345 // Update the residency of the cache line. If the response has no
346 // sharers we know that the line has been invalidated in all
347 // branches that are not where we are responding to.
348 if (!cpkt->hasSharers())
349 sf_item.holder = 0;
350 sf_item.holder |= slave_mask;
351 sf_item.requested &= ~slave_mask;
352 assert(sf_item.holder | sf_item.requested);
353 DPRINTF(SnoopFilter, "%s: new SF value %x.%x\n",
354 __func__, sf_item.requested, sf_item.holder);
355}
356
357void
358SnoopFilter::regStats()
359{
360 SimObject::regStats();
361
362 totRequests
363 .name(name() + ".tot_requests")
364 .desc("Total number of requests made to the snoop filter.");
365
366 hitSingleRequests
367 .name(name() + ".hit_single_requests")
368 .desc("Number of requests hitting in the snoop filter with a single "\
369 "holder of the requested data.");
370
371 hitMultiRequests
372 .name(name() + ".hit_multi_requests")
373 .desc("Number of requests hitting in the snoop filter with multiple "\
374 "(>1) holders of the requested data.");
375
376 totSnoops
377 .name(name() + ".tot_snoops")
378 .desc("Total number of snoops made to the snoop filter.");
379
380 hitSingleSnoops
381 .name(name() + ".hit_single_snoops")
382 .desc("Number of snoops hitting in the snoop filter with a single "\
383 "holder of the requested data.");
384
385 hitMultiSnoops
386 .name(name() + ".hit_multi_snoops")
387 .desc("Number of snoops hitting in the snoop filter with multiple "\
388 "(>1) holders of the requested data.");
389}
390
391SnoopFilter *
392SnoopFilterParams::create()
393{
394 return new SnoopFilter(this);
395}
| 350 auto sf_it = cachedLocations.find(line_addr);
351 if (sf_it == cachedLocations.end())
352 return;
353
354 SnoopMask slave_mask = portToMask(slave_port);
355 SnoopItem& sf_item = sf_it->second;
356
357 DPRINTF(SnoopFilter, "%s: old SF value %x.%x\n",
358 __func__, sf_item.requested, sf_item.holder);
359
360 // Make sure we have seen the actual request, too
361 panic_if(!(sf_item.requested & slave_mask), "SF value %x.%x missing "\
362 "request bit\n", sf_item.requested, sf_item.holder);
363
364 // Update the residency of the cache line. If the response has no
365 // sharers we know that the line has been invalidated in all
366 // branches that are not where we are responding to.
367 if (!cpkt->hasSharers())
368 sf_item.holder = 0;
369 sf_item.holder |= slave_mask;
370 sf_item.requested &= ~slave_mask;
371 assert(sf_item.holder | sf_item.requested);
372 DPRINTF(SnoopFilter, "%s: new SF value %x.%x\n",
373 __func__, sf_item.requested, sf_item.holder);
374}
375
376void
377SnoopFilter::regStats()
378{
379 SimObject::regStats();
380
381 totRequests
382 .name(name() + ".tot_requests")
383 .desc("Total number of requests made to the snoop filter.");
384
385 hitSingleRequests
386 .name(name() + ".hit_single_requests")
387 .desc("Number of requests hitting in the snoop filter with a single "\
388 "holder of the requested data.");
389
390 hitMultiRequests
391 .name(name() + ".hit_multi_requests")
392 .desc("Number of requests hitting in the snoop filter with multiple "\
393 "(>1) holders of the requested data.");
394
395 totSnoops
396 .name(name() + ".tot_snoops")
397 .desc("Total number of snoops made to the snoop filter.");
398
399 hitSingleSnoops
400 .name(name() + ".hit_single_snoops")
401 .desc("Number of snoops hitting in the snoop filter with a single "\
402 "holder of the requested data.");
403
404 hitMultiSnoops
405 .name(name() + ".hit_multi_snoops")
406 .desc("Number of snoops hitting in the snoop filter with multiple "\
407 "(>1) holders of the requested data.");
408}
409
410SnoopFilter *
411SnoopFilterParams::create()
412{
413 return new SnoopFilter(this);
414}
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