1 /*
2 * QEMU Machine core (related to -smp parsing)
3 *
4 * Copyright (c) 2021 Huawei Technologies Co., Ltd
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License,
9 * or (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, see <http://www.gnu.org/licenses/>.
18 */
19
20 #include "qemu/osdep.h"
21 #include "hw/boards.h"
22 #include "qapi/error.h"
23 #include "qemu/error-report.h"
24
25
26 /*
27 * Report information of a machine's supported CPU topology hierarchy.
28 * Topology members will be ordered from the largest to the smallest
29 * in the string.
30 */
cpu_hierarchy_to_string(MachineState * ms)31 static char *cpu_hierarchy_to_string(MachineState *ms)
32 {
33 MachineClass *mc = MACHINE_GET_CLASS(ms);
34 GString *s = g_string_new(NULL);
35
36 if (mc->smp_props.drawers_supported) {
37 g_string_append_printf(s, "drawers (%u) * ", ms->smp.drawers);
38 }
39
40 if (mc->smp_props.books_supported) {
41 g_string_append_printf(s, "books (%u) * ", ms->smp.books);
42 }
43
44 g_string_append_printf(s, "sockets (%u)", ms->smp.sockets);
45
46 if (mc->smp_props.dies_supported) {
47 g_string_append_printf(s, " * dies (%u)", ms->smp.dies);
48 }
49
50 if (mc->smp_props.clusters_supported) {
51 g_string_append_printf(s, " * clusters (%u)", ms->smp.clusters);
52 }
53
54 if (mc->smp_props.modules_supported) {
55 g_string_append_printf(s, " * modules (%u)", ms->smp.modules);
56 }
57
58 g_string_append_printf(s, " * cores (%u)", ms->smp.cores);
59 g_string_append_printf(s, " * threads (%u)", ms->smp.threads);
60
61 return g_string_free(s, false);
62 }
63
64 /*
65 * machine_parse_smp_config: Generic function used to parse the given
66 * SMP configuration
67 *
68 * Any missing parameter in "cpus/maxcpus/sockets/cores/threads" will be
69 * automatically computed based on the provided ones.
70 *
71 * In the calculation of omitted sockets/cores/threads: we prefer sockets
72 * over cores over threads before 6.2, while preferring cores over sockets
73 * over threads since 6.2.
74 *
75 * In the calculation of cpus/maxcpus: When both maxcpus and cpus are omitted,
76 * maxcpus will be computed from the given parameters and cpus will be set
77 * equal to maxcpus. When only one of maxcpus and cpus is given then the
78 * omitted one will be set to its given counterpart's value. Both maxcpus and
79 * cpus may be specified, but maxcpus must be equal to or greater than cpus.
80 *
81 * For compatibility, apart from the parameters that will be computed, newly
82 * introduced topology members which are likely to be target specific should
83 * be directly set as 1 if they are omitted (e.g. dies for PC since 4.1).
84 */
machine_parse_smp_config(MachineState * ms,const SMPConfiguration * config,Error ** errp)85 void machine_parse_smp_config(MachineState *ms,
86 const SMPConfiguration *config, Error **errp)
87 {
88 MachineClass *mc = MACHINE_GET_CLASS(ms);
89 unsigned cpus = config->has_cpus ? config->cpus : 0;
90 unsigned drawers = config->has_drawers ? config->drawers : 0;
91 unsigned books = config->has_books ? config->books : 0;
92 unsigned sockets = config->has_sockets ? config->sockets : 0;
93 unsigned dies = config->has_dies ? config->dies : 0;
94 unsigned clusters = config->has_clusters ? config->clusters : 0;
95 unsigned modules = config->has_modules ? config->modules : 0;
96 unsigned cores = config->has_cores ? config->cores : 0;
97 unsigned threads = config->has_threads ? config->threads : 0;
98 unsigned maxcpus = config->has_maxcpus ? config->maxcpus : 0;
99 unsigned total_cpus;
100
101 /*
102 * Specified CPU topology parameters must be greater than zero,
103 * explicit configuration like "cpus=0" is not allowed.
104 */
105 if ((config->has_cpus && config->cpus == 0) ||
106 (config->has_drawers && config->drawers == 0) ||
107 (config->has_books && config->books == 0) ||
108 (config->has_sockets && config->sockets == 0) ||
109 (config->has_dies && config->dies == 0) ||
110 (config->has_clusters && config->clusters == 0) ||
111 (config->has_modules && config->modules == 0) ||
112 (config->has_cores && config->cores == 0) ||
113 (config->has_threads && config->threads == 0) ||
114 (config->has_maxcpus && config->maxcpus == 0)) {
115 error_setg(errp, "Invalid CPU topology: "
116 "CPU topology parameters must be greater than zero");
117 return;
118 }
119
120 /*
121 * If not supported by the machine, a topology parameter must
122 * not be set to a value greater than 1.
123 */
124 if (!mc->smp_props.modules_supported &&
125 config->has_modules && config->modules > 1) {
126 error_setg(errp,
127 "modules > 1 not supported by this machine's CPU topology");
128 return;
129 }
130 modules = modules > 0 ? modules : 1;
131
132 if (!mc->smp_props.clusters_supported &&
133 config->has_clusters && config->clusters > 1) {
134 error_setg(errp,
135 "clusters > 1 not supported by this machine's CPU topology");
136 return;
137 }
138 clusters = clusters > 0 ? clusters : 1;
139
140 if (!mc->smp_props.dies_supported &&
141 config->has_dies && config->dies > 1) {
142 error_setg(errp,
143 "dies > 1 not supported by this machine's CPU topology");
144 return;
145 }
146 dies = dies > 0 ? dies : 1;
147
148 if (!mc->smp_props.books_supported &&
149 config->has_books && config->books > 1) {
150 error_setg(errp,
151 "books > 1 not supported by this machine's CPU topology");
152 return;
153 }
154 books = books > 0 ? books : 1;
155
156 if (!mc->smp_props.drawers_supported &&
157 config->has_drawers && config->drawers > 1) {
158 error_setg(errp,
159 "drawers > 1 not supported by this machine's CPU topology");
160 return;
161 }
162 drawers = drawers > 0 ? drawers : 1;
163
164 /* compute missing values based on the provided ones */
165 if (cpus == 0 && maxcpus == 0) {
166 sockets = sockets > 0 ? sockets : 1;
167 cores = cores > 0 ? cores : 1;
168 threads = threads > 0 ? threads : 1;
169 } else {
170 maxcpus = maxcpus > 0 ? maxcpus : cpus;
171
172 if (mc->smp_props.prefer_sockets) {
173 /* prefer sockets over cores before 6.2 */
174 if (sockets == 0) {
175 cores = cores > 0 ? cores : 1;
176 threads = threads > 0 ? threads : 1;
177 sockets = maxcpus /
178 (drawers * books * dies * clusters *
179 modules * cores * threads);
180 } else if (cores == 0) {
181 threads = threads > 0 ? threads : 1;
182 cores = maxcpus /
183 (drawers * books * sockets * dies *
184 clusters * modules * threads);
185 }
186 } else {
187 /* prefer cores over sockets since 6.2 */
188 if (cores == 0) {
189 sockets = sockets > 0 ? sockets : 1;
190 threads = threads > 0 ? threads : 1;
191 cores = maxcpus /
192 (drawers * books * sockets * dies *
193 clusters * modules * threads);
194 } else if (sockets == 0) {
195 threads = threads > 0 ? threads : 1;
196 sockets = maxcpus /
197 (drawers * books * dies * clusters *
198 modules * cores * threads);
199 }
200 }
201
202 /* try to calculate omitted threads at last */
203 if (threads == 0) {
204 threads = maxcpus /
205 (drawers * books * sockets * dies *
206 clusters * modules * cores);
207 }
208 }
209
210 total_cpus = drawers * books * sockets * dies *
211 clusters * modules * cores * threads;
212 maxcpus = maxcpus > 0 ? maxcpus : total_cpus;
213 cpus = cpus > 0 ? cpus : maxcpus;
214
215 ms->smp.cpus = cpus;
216 ms->smp.drawers = drawers;
217 ms->smp.books = books;
218 ms->smp.sockets = sockets;
219 ms->smp.dies = dies;
220 ms->smp.clusters = clusters;
221 ms->smp.modules = modules;
222 ms->smp.cores = cores;
223 ms->smp.threads = threads;
224 ms->smp.max_cpus = maxcpus;
225
226 mc->smp_props.has_clusters = config->has_clusters;
227
228 /* sanity-check of the computed topology */
229 if (total_cpus != maxcpus) {
230 g_autofree char *topo_msg = cpu_hierarchy_to_string(ms);
231 error_setg(errp, "Invalid CPU topology: "
232 "product of the hierarchy must match maxcpus: "
233 "%s != maxcpus (%u)",
234 topo_msg, maxcpus);
235 return;
236 }
237
238 if (maxcpus < cpus) {
239 g_autofree char *topo_msg = cpu_hierarchy_to_string(ms);
240 error_setg(errp, "Invalid CPU topology: "
241 "maxcpus must be equal to or greater than smp: "
242 "%s == maxcpus (%u) < smp_cpus (%u)",
243 topo_msg, maxcpus, cpus);
244 return;
245 }
246
247 if (ms->smp.cpus < mc->min_cpus) {
248 error_setg(errp, "Invalid SMP CPUs %d. The min CPUs "
249 "supported by machine '%s' is %d",
250 ms->smp.cpus,
251 mc->name, mc->min_cpus);
252 return;
253 }
254
255 if (ms->smp.max_cpus > mc->max_cpus) {
256 error_setg(errp, "Invalid SMP CPUs %d. The max CPUs "
257 "supported by machine '%s' is %d",
258 ms->smp.max_cpus,
259 mc->name, mc->max_cpus);
260 return;
261 }
262 }
263
machine_check_topo_support(MachineState * ms,CpuTopologyLevel topo,Error ** errp)264 static bool machine_check_topo_support(MachineState *ms,
265 CpuTopologyLevel topo,
266 Error **errp)
267 {
268 MachineClass *mc = MACHINE_GET_CLASS(ms);
269
270 if ((topo == CPU_TOPOLOGY_LEVEL_MODULE && !mc->smp_props.modules_supported) ||
271 (topo == CPU_TOPOLOGY_LEVEL_CLUSTER && !mc->smp_props.clusters_supported) ||
272 (topo == CPU_TOPOLOGY_LEVEL_DIE && !mc->smp_props.dies_supported) ||
273 (topo == CPU_TOPOLOGY_LEVEL_BOOK && !mc->smp_props.books_supported) ||
274 (topo == CPU_TOPOLOGY_LEVEL_DRAWER && !mc->smp_props.drawers_supported)) {
275 error_setg(errp,
276 "Invalid topology level: %s. "
277 "The topology level is not supported by this machine",
278 CpuTopologyLevel_str(topo));
279 return false;
280 }
281
282 return true;
283 }
284
machine_parse_smp_cache(MachineState * ms,const SmpCachePropertiesList * caches,Error ** errp)285 bool machine_parse_smp_cache(MachineState *ms,
286 const SmpCachePropertiesList *caches,
287 Error **errp)
288 {
289 MachineClass *mc = MACHINE_GET_CLASS(ms);
290 const SmpCachePropertiesList *node;
291 DECLARE_BITMAP(caches_bitmap, CACHE_LEVEL_AND_TYPE__MAX);
292
293 bitmap_zero(caches_bitmap, CACHE_LEVEL_AND_TYPE__MAX);
294 for (node = caches; node; node = node->next) {
295 /* Prohibit users from repeating settings. */
296 if (test_bit(node->value->cache, caches_bitmap)) {
297 error_setg(errp,
298 "Invalid cache properties: %s. "
299 "The cache properties are duplicated",
300 CacheLevelAndType_str(node->value->cache));
301 return false;
302 }
303
304 machine_set_cache_topo_level(ms, node->value->cache,
305 node->value->topology);
306 set_bit(node->value->cache, caches_bitmap);
307 }
308
309 for (int i = 0; i < CACHE_LEVEL_AND_TYPE__MAX; i++) {
310 const SmpCacheProperties *props = &ms->smp_cache.props[i];
311
312 /*
313 * Reject non "default" topology level if the cache isn't
314 * supported by the machine.
315 */
316 if (props->topology != CPU_TOPOLOGY_LEVEL_DEFAULT &&
317 !mc->smp_props.cache_supported[props->cache]) {
318 error_setg(errp,
319 "%s cache topology not supported by this machine",
320 CacheLevelAndType_str(props->cache));
321 return false;
322 }
323
324 if (!machine_check_topo_support(ms, props->topology, errp)) {
325 return false;
326 }
327 }
328 return true;
329 }
330
machine_topo_get_cores_per_socket(const MachineState * ms)331 unsigned int machine_topo_get_cores_per_socket(const MachineState *ms)
332 {
333 return ms->smp.cores * ms->smp.modules * ms->smp.clusters * ms->smp.dies;
334 }
335
machine_topo_get_threads_per_socket(const MachineState * ms)336 unsigned int machine_topo_get_threads_per_socket(const MachineState *ms)
337 {
338 return ms->smp.threads * machine_topo_get_cores_per_socket(ms);
339 }
340
machine_get_cache_topo_level(const MachineState * ms,CacheLevelAndType cache)341 CpuTopologyLevel machine_get_cache_topo_level(const MachineState *ms,
342 CacheLevelAndType cache)
343 {
344 return ms->smp_cache.props[cache].topology;
345 }
346
machine_set_cache_topo_level(MachineState * ms,CacheLevelAndType cache,CpuTopologyLevel level)347 void machine_set_cache_topo_level(MachineState *ms, CacheLevelAndType cache,
348 CpuTopologyLevel level)
349 {
350 ms->smp_cache.props[cache].topology = level;
351 }
352
353 /*
354 * When both cache1 and cache2 are configured with specific topology levels
355 * (not default level), is cache1's topology level higher than cache2?
356 */
smp_cache_topo_cmp(const SmpCache * smp_cache,CacheLevelAndType cache1,CacheLevelAndType cache2)357 static bool smp_cache_topo_cmp(const SmpCache *smp_cache,
358 CacheLevelAndType cache1,
359 CacheLevelAndType cache2)
360 {
361 /*
362 * Before comparing, the "default" topology level should be replaced
363 * with the specific level.
364 */
365 assert(smp_cache->props[cache1].topology != CPU_TOPOLOGY_LEVEL_DEFAULT);
366
367 return smp_cache->props[cache1].topology > smp_cache->props[cache2].topology;
368 }
369
370 /*
371 * Currently, we have no way to expose the arch-specific default cache model
372 * because the cache model is sometimes related to the CPU model (e.g., i386).
373 *
374 * We can only check the correctness of the cache topology after the arch loads
375 * the user-configured cache model from MachineState and consumes the special
376 * "default" level by replacing it with the specific level.
377 */
machine_check_smp_cache(const MachineState * ms,Error ** errp)378 bool machine_check_smp_cache(const MachineState *ms, Error **errp)
379 {
380 if (smp_cache_topo_cmp(&ms->smp_cache, CACHE_LEVEL_AND_TYPE_L1D,
381 CACHE_LEVEL_AND_TYPE_L2) ||
382 smp_cache_topo_cmp(&ms->smp_cache, CACHE_LEVEL_AND_TYPE_L1I,
383 CACHE_LEVEL_AND_TYPE_L2)) {
384 error_setg(errp,
385 "Invalid smp cache topology. "
386 "L2 cache topology level shouldn't be lower than L1 cache");
387 return false;
388 }
389
390 if (smp_cache_topo_cmp(&ms->smp_cache, CACHE_LEVEL_AND_TYPE_L2,
391 CACHE_LEVEL_AND_TYPE_L3)) {
392 error_setg(errp,
393 "Invalid smp cache topology. "
394 "L3 cache topology level shouldn't be lower than L2 cache");
395 return false;
396 }
397
398 return true;
399 }
400