arch/x86/events/amd/uncore.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2013 Advanced Micro Devices, Inc.
   4  *
   5  * Author: Jacob Shin <jacob.shin@amd.com>
   6  */
   7
   8 #include <linux/perf_event.h>
   9 #include <linux/percpu.h>
  10 #include <linux/types.h>
  11 #include <linux/slab.h>
  12 #include <linux/init.h>
  13 #include <linux/cpu.h>
  14 #include <linux/cpumask.h>
  15
  16 #include <asm/cpufeature.h>
  17 #include <asm/perf_event.h>
  18 #include <asm/msr.h>
  19 #include <asm/smp.h>
  20
  21 #define NUM_COUNTERS_NB         4
  22 #define NUM_COUNTERS_L2         4
  23 #define NUM_COUNTERS_L3         6
  24 #define MAX_COUNTERS            6
  25
  26 #define RDPMC_BASE_NB           6
  27 #define RDPMC_BASE_LLC          10
  28
  29 #define COUNTER_SHIFT           16
  30
  31 #undef pr_fmt
  32 #define pr_fmt(fmt)     "amd_uncore: " fmt
  33
  34 static int num_counters_llc;
  35 static int num_counters_nb;
  36 static bool l3_mask;
  37
  38 static HLIST_HEAD(uncore_unused_list);
  39
  40 struct amd_uncore {
  41         int id;
  42         int refcnt;
  43         int cpu;
  44         int num_counters;
  45         int rdpmc_base;
  46         u32 msr_base;
  47         cpumask_t *active_mask;
  48         struct pmu *pmu;
  49         struct perf_event *events[MAX_COUNTERS];
  50         struct hlist_node node;
  51 };
  52
  53 static struct amd_uncore * __percpu *amd_uncore_nb;
  54 static struct amd_uncore * __percpu *amd_uncore_llc;
  55
  56 static struct pmu amd_nb_pmu;
  57 static struct pmu amd_llc_pmu;
  58
  59 static cpumask_t amd_nb_active_mask;
  60 static cpumask_t amd_llc_active_mask;
  61
  62 static bool is_nb_event(struct perf_event *event)
  63 {
  64         return event->pmu->type == amd_nb_pmu.type;
  65 }
  66
  67 static bool is_llc_event(struct perf_event *event)
  68 {
  69         return event->pmu->type == amd_llc_pmu.type;
  70 }
  71
  72 static struct amd_uncore *event_to_amd_uncore(struct perf_event *event)
  73 {
  74         if (is_nb_event(event) && amd_uncore_nb)
  75                 return *per_cpu_ptr(amd_uncore_nb, event->cpu);
  76         else if (is_llc_event(event) && amd_uncore_llc)
  77                 return *per_cpu_ptr(amd_uncore_llc, event->cpu);
  78
  79         return NULL;
  80 }
  81
  82 static void amd_uncore_read(struct perf_event *event)
  83 {
  84         struct hw_perf_event *hwc = &event->hw;
  85         u64 prev, new;
  86         s64 delta;
  87
  88         /*
  89          * since we do not enable counter overflow interrupts,
  90          * we do not have to worry about prev_count changing on us
  91          */
  92
  93         prev = local64_read(&hwc->prev_count);
  94         rdpmcl(hwc->event_base_rdpmc, new);
  95         local64_set(&hwc->prev_count, new);
  96         delta = (new << COUNTER_SHIFT) - (prev << COUNTER_SHIFT);
  97         delta >>= COUNTER_SHIFT;
  98         local64_add(delta, &event->count);
  99 }
 100
 101 static void amd_uncore_start(struct perf_event *event, int flags)
 102 {
 103         struct hw_perf_event *hwc = &event->hw;
 104
 105         if (flags & PERF_EF_RELOAD)
 106                 wrmsrl(hwc->event_base, (u64)local64_read(&hwc->prev_count));
 107
 108         hwc->state = 0;
 109         wrmsrl(hwc->config_base, (hwc->config | ARCH_PERFMON_EVENTSEL_ENABLE));
 110         perf_event_update_userpage(event);
 111 }
 112
 113 static void amd_uncore_stop(struct perf_event *event, int flags)
 114 {
 115         struct hw_perf_event *hwc = &event->hw;
 116
 117         wrmsrl(hwc->config_base, hwc->config);
 118         hwc->state |= PERF_HES_STOPPED;
 119
 120         if ((flags & PERF_EF_UPDATE) && !(hwc->state & PERF_HES_UPTODATE)) {
 121                 amd_uncore_read(event);
 122                 hwc->state |= PERF_HES_UPTODATE;
 123         }
 124 }
 125
 126 static int amd_uncore_add(struct perf_event *event, int flags)
 127 {
 128         int i;
 129         struct amd_uncore *uncore = event_to_amd_uncore(event);
 130         struct hw_perf_event *hwc = &event->hw;
 131
 132         /* are we already assigned? */
 133         if (hwc->idx != -1 && uncore->events[hwc->idx] == event)
 134                 goto out;
 135
 136         for (i = 0; i < uncore->num_counters; i++) {
 137                 if (uncore->events[i] == event) {
 138                         hwc->idx = i;
 139                         goto out;
 140                 }
 141         }
 142
 143         /* if not, take the first available counter */
 144         hwc->idx = -1;
 145         for (i = 0; i < uncore->num_counters; i++) {
 146                 if (cmpxchg(&uncore->events[i], NULL, event) == NULL) {
 147                         hwc->idx = i;
 148                         break;
 149                 }
 150         }
 151
 152 out:
 153         if (hwc->idx == -1)
 154                 return -EBUSY;
 155
 156         hwc->config_base = uncore->msr_base + (2 * hwc->idx);
 157         hwc->event_base = uncore->msr_base + 1 + (2 * hwc->idx);
 158         hwc->event_base_rdpmc = uncore->rdpmc_base + hwc->idx;
 159         hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
 160
 161         if (flags & PERF_EF_START)
 162                 amd_uncore_start(event, PERF_EF_RELOAD);
 163
 164         return 0;
 165 }
 166
 167 static void amd_uncore_del(struct perf_event *event, int flags)
 168 {
 169         int i;
 170         struct amd_uncore *uncore = event_to_amd_uncore(event);
 171         struct hw_perf_event *hwc = &event->hw;
 172
 173         amd_uncore_stop(event, PERF_EF_UPDATE);
 174
 175         for (i = 0; i < uncore->num_counters; i++) {
 176                 if (cmpxchg(&uncore->events[i], event, NULL) == event)
 177                         break;
 178         }
 179
 180         hwc->idx = -1;
 181 }
 182
 183 static int amd_uncore_event_init(struct perf_event *event)
 184 {
 185         struct amd_uncore *uncore;
 186         struct hw_perf_event *hwc = &event->hw;
 187
 188         if (event->attr.type != event->pmu->type)
 189                 return -ENOENT;
 190
 191         /*
 192          * NB and Last level cache counters (MSRs) are shared across all cores
 193          * that share the same NB / Last level cache. Interrupts can be directed
 194          * to a single target core, however, event counts generated by processes
 195          * running on other cores cannot be masked out. So we do not support
 196          * sampling and per-thread events.
 197          */
 198         if (is_sampling_event(event) || event->attach_state & PERF_ATTACH_TASK)
 199                 return -EINVAL;
 200
 201         /* and we do not enable counter overflow interrupts */
 202         hwc->config = event->attr.config & AMD64_RAW_EVENT_MASK_NB;
 203         hwc->idx = -1;
 204
 205         /*
 206          * SliceMask and ThreadMask need to be set for certain L3 events in
 207          * Family 17h. For other events, the two fields do not affect the count.
 208          */
 209         if (l3_mask)
 210                 hwc->config |= (AMD64_L3_SLICE_MASK | AMD64_L3_THREAD_MASK);
 211
 212         if (event->cpu < 0)
 213                 return -EINVAL;
 214
 215         uncore = event_to_amd_uncore(event);
 216         if (!uncore)
 217                 return -ENODEV;
 218
 219         /*
 220          * since request can come in to any of the shared cores, we will remap
 221          * to a single common cpu.
 222          */
 223         event->cpu = uncore->cpu;
 224
 225         return 0;
 226 }
 227
 228 static ssize_t amd_uncore_attr_show_cpumask(struct device *dev,
 229                                             struct device_attribute *attr,
 230                                             char *buf)
 231 {
 232         cpumask_t *active_mask;
 233         struct pmu *pmu = dev_get_drvdata(dev);
 234
 235         if (pmu->type == amd_nb_pmu.type)
 236                 active_mask = &amd_nb_active_mask;
 237         else if (pmu->type == amd_llc_pmu.type)
 238                 active_mask = &amd_llc_active_mask;
 239         else
 240                 return 0;
 241
 242         return cpumap_print_to_pagebuf(true, buf, active_mask);
 243 }
 244 static DEVICE_ATTR(cpumask, S_IRUGO, amd_uncore_attr_show_cpumask, NULL);
 245
 246 static struct attribute *amd_uncore_attrs[] = {
 247         &dev_attr_cpumask.attr,
 248         NULL,
 249 };
 250
 251 static struct attribute_group amd_uncore_attr_group = {
 252         .attrs = amd_uncore_attrs,
 253 };
 254
 255 /*
 256  * Similar to PMU_FORMAT_ATTR but allowing for format_attr to be assigned based
 257  * on family
 258  */
 259 #define AMD_FORMAT_ATTR(_dev, _name, _format)                                \
 260 static ssize_t                                                               \
 261 _dev##_show##_name(struct device *dev,                                       \
 262                 struct device_attribute *attr,                               \
 263                 char *page)                                                  \
 264 {                                                                            \
 265         BUILD_BUG_ON(sizeof(_format) >= PAGE_SIZE);                          \
 266         return sprintf(page, _format "\n");                                  \
 267 }                                                                            \
 268 static struct device_attribute format_attr_##_dev##_name = __ATTR_RO(_dev);
 269
 270 /* Used for each uncore counter type */
 271 #define AMD_ATTRIBUTE(_name)                                                 \
 272 static struct attribute *amd_uncore_format_attr_##_name[] = {                \
 273         &format_attr_event_##_name.attr,                                     \
 274         &format_attr_umask.attr,                                             \
 275         NULL,                                                                \
 276 };                                                                           \
 277 static struct attribute_group amd_uncore_format_group_##_name = {            \
 278         .name = "format",                                                    \
 279         .attrs = amd_uncore_format_attr_##_name,                             \
 280 };                                                                           \
 281 static const struct attribute_group *amd_uncore_attr_groups_##_name[] = {    \
 282         &amd_uncore_attr_group,                                              \
 283         &amd_uncore_format_group_##_name,                                    \
 284         NULL,                                                                \
 285 };
 286
 287 AMD_FORMAT_ATTR(event, , "config:0-7,32-35");
 288 AMD_FORMAT_ATTR(umask, , "config:8-15");
 289 AMD_FORMAT_ATTR(event, _df, "config:0-7,32-35,59-60");
 290 AMD_FORMAT_ATTR(event, _l3, "config:0-7");
 291 AMD_ATTRIBUTE(df);
 292 AMD_ATTRIBUTE(l3);
 293
 294 static struct pmu amd_nb_pmu = {
 295         .task_ctx_nr    = perf_invalid_context,
 296         .event_init     = amd_uncore_event_init,
 297         .add            = amd_uncore_add,
 298         .del            = amd_uncore_del,
 299         .start          = amd_uncore_start,
 300         .stop           = amd_uncore_stop,
 301         .read           = amd_uncore_read,
 302         .capabilities   = PERF_PMU_CAP_NO_EXCLUDE,
 303 };
 304
 305 static struct pmu amd_llc_pmu = {
 306         .task_ctx_nr    = perf_invalid_context,
 307         .event_init     = amd_uncore_event_init,
 308         .add            = amd_uncore_add,
 309         .del            = amd_uncore_del,
 310         .start          = amd_uncore_start,
 311         .stop           = amd_uncore_stop,
 312         .read           = amd_uncore_read,
 313         .capabilities   = PERF_PMU_CAP_NO_EXCLUDE,
 314 };
 315
 316 static struct amd_uncore *amd_uncore_alloc(unsigned int cpu)
 317 {
 318         return kzalloc_node(sizeof(struct amd_uncore), GFP_KERNEL,
 319                         cpu_to_node(cpu));
 320 }
 321
 322 static int amd_uncore_cpu_up_prepare(unsigned int cpu)
 323 {
 324         struct amd_uncore *uncore_nb = NULL, *uncore_llc;
 325
 326         if (amd_uncore_nb) {
 327                 uncore_nb = amd_uncore_alloc(cpu);
 328                 if (!uncore_nb)
 329                         goto fail;
 330                 uncore_nb->cpu = cpu;
 331                 uncore_nb->num_counters = num_counters_nb;
 332                 uncore_nb->rdpmc_base = RDPMC_BASE_NB;
 333                 uncore_nb->msr_base = MSR_F15H_NB_PERF_CTL;
 334                 uncore_nb->active_mask = &amd_nb_active_mask;
 335                 uncore_nb->pmu = &amd_nb_pmu;
 336                 uncore_nb->id = -1;
 337                 *per_cpu_ptr(amd_uncore_nb, cpu) = uncore_nb;
 338         }
 339
 340         if (amd_uncore_llc) {
 341                 uncore_llc = amd_uncore_alloc(cpu);
 342                 if (!uncore_llc)
 343                         goto fail;
 344                 uncore_llc->cpu = cpu;
 345                 uncore_llc->num_counters = num_counters_llc;
 346                 uncore_llc->rdpmc_base = RDPMC_BASE_LLC;
 347                 uncore_llc->msr_base = MSR_F16H_L2I_PERF_CTL;
 348                 uncore_llc->active_mask = &amd_llc_active_mask;
 349                 uncore_llc->pmu = &amd_llc_pmu;
 350                 uncore_llc->id = -1;
 351                 *per_cpu_ptr(amd_uncore_llc, cpu) = uncore_llc;
 352         }
 353
 354         return 0;
 355
 356 fail:
 357         if (amd_uncore_nb)
 358                 *per_cpu_ptr(amd_uncore_nb, cpu) = NULL;
 359         kfree(uncore_nb);
 360         return -ENOMEM;
 361 }
 362
 363 static struct amd_uncore *
 364 amd_uncore_find_online_sibling(struct amd_uncore *this,
 365                                struct amd_uncore * __percpu *uncores)
 366 {
 367         unsigned int cpu;
 368         struct amd_uncore *that;
 369
 370         for_each_online_cpu(cpu) {
 371                 that = *per_cpu_ptr(uncores, cpu);
 372
 373                 if (!that)
 374                         continue;
 375
 376                 if (this == that)
 377                         continue;
 378
 379                 if (this->id == that->id) {
 380                         hlist_add_head(&this->node, &uncore_unused_list);
 381                         this = that;
 382                         break;
 383                 }
 384         }
 385
 386         this->refcnt++;
 387         return this;
 388 }
 389
 390 static int amd_uncore_cpu_starting(unsigned int cpu)
 391 {
 392         unsigned int eax, ebx, ecx, edx;
 393         struct amd_uncore *uncore;
 394
 395         if (amd_uncore_nb) {
 396                 uncore = *per_cpu_ptr(amd_uncore_nb, cpu);
 397                 cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);
 398                 uncore->id = ecx & 0xff;
 399
 400                 uncore = amd_uncore_find_online_sibling(uncore, amd_uncore_nb);
 401                 *per_cpu_ptr(amd_uncore_nb, cpu) = uncore;
 402         }
 403
 404         if (amd_uncore_llc) {
 405                 uncore = *per_cpu_ptr(amd_uncore_llc, cpu);
 406                 uncore->id = per_cpu(cpu_llc_id, cpu);
 407
 408                 uncore = amd_uncore_find_online_sibling(uncore, amd_uncore_llc);
 409                 *per_cpu_ptr(amd_uncore_llc, cpu) = uncore;
 410         }
 411
 412         return 0;
 413 }
 414
 415 static void uncore_clean_online(void)
 416 {
 417         struct amd_uncore *uncore;
 418         struct hlist_node *n;
 419
 420         hlist_for_each_entry_safe(uncore, n, &uncore_unused_list, node) {
 421                 hlist_del(&uncore->node);
 422                 kfree(uncore);
 423         }
 424 }
 425
 426 static void uncore_online(unsigned int cpu,
 427                           struct amd_uncore * __percpu *uncores)
 428 {
 429         struct amd_uncore *uncore = *per_cpu_ptr(uncores, cpu);
 430
 431         uncore_clean_online();
 432
 433         if (cpu == uncore->cpu)
 434                 cpumask_set_cpu(cpu, uncore->active_mask);
 435 }
 436
 437 static int amd_uncore_cpu_online(unsigned int cpu)
 438 {
 439         if (amd_uncore_nb)
 440                 uncore_online(cpu, amd_uncore_nb);
 441
 442         if (amd_uncore_llc)
 443                 uncore_online(cpu, amd_uncore_llc);
 444
 445         return 0;
 446 }
 447
 448 static void uncore_down_prepare(unsigned int cpu,
 449                                 struct amd_uncore * __percpu *uncores)
 450 {
 451         unsigned int i;
 452         struct amd_uncore *this = *per_cpu_ptr(uncores, cpu);
 453
 454         if (this->cpu != cpu)
 455                 return;
 456
 457         /* this cpu is going down, migrate to a shared sibling if possible */
 458         for_each_online_cpu(i) {
 459                 struct amd_uncore *that = *per_cpu_ptr(uncores, i);
 460
 461                 if (cpu == i)
 462                         continue;
 463
 464                 if (this == that) {
 465                         perf_pmu_migrate_context(this->pmu, cpu, i);
 466                         cpumask_clear_cpu(cpu, that->active_mask);
 467                         cpumask_set_cpu(i, that->active_mask);
 468                         that->cpu = i;
 469                         break;
 470                 }
 471         }
 472 }
 473
 474 static int amd_uncore_cpu_down_prepare(unsigned int cpu)
 475 {
 476         if (amd_uncore_nb)
 477                 uncore_down_prepare(cpu, amd_uncore_nb);
 478
 479         if (amd_uncore_llc)
 480                 uncore_down_prepare(cpu, amd_uncore_llc);
 481
 482         return 0;
 483 }
 484
 485 static void uncore_dead(unsigned int cpu, struct amd_uncore * __percpu *uncores)
 486 {
 487         struct amd_uncore *uncore = *per_cpu_ptr(uncores, cpu);
 488
 489         if (cpu == uncore->cpu)
 490                 cpumask_clear_cpu(cpu, uncore->active_mask);
 491
 492         if (!--uncore->refcnt)
 493                 kfree(uncore);
 494         *per_cpu_ptr(uncores, cpu) = NULL;
 495 }
 496
 497 static int amd_uncore_cpu_dead(unsigned int cpu)
 498 {
 499         if (amd_uncore_nb)
 500                 uncore_dead(cpu, amd_uncore_nb);
 501
 502         if (amd_uncore_llc)
 503                 uncore_dead(cpu, amd_uncore_llc);
 504
 505         return 0;
 506 }
 507
 508 static int __init amd_uncore_init(void)
 509 {
 510         int ret = -ENODEV;
 511
 512         if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
 513             boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
 514                 return -ENODEV;
 515
 516         if (!boot_cpu_has(X86_FEATURE_TOPOEXT))
 517                 return -ENODEV;
 518
 519         if (boot_cpu_data.x86 == 0x17 || boot_cpu_data.x86 == 0x18) {
 520                 /*
 521                  * For F17h or F18h, the Northbridge counters are
 522                  * repurposed as Data Fabric counters. Also, L3
 523                  * counters are supported too. The PMUs are exported
 524                  * based on family as either L2 or L3 and NB or DF.
 525                  */
 526                 num_counters_nb           = NUM_COUNTERS_NB;
 527                 num_counters_llc          = NUM_COUNTERS_L3;
 528                 amd_nb_pmu.name           = "amd_df";
 529                 amd_llc_pmu.name          = "amd_l3";
 530                 format_attr_event_df.show = &event_show_df;
 531                 format_attr_event_l3.show = &event_show_l3;
 532                 l3_mask                   = true;
 533         } else {
 534                 num_counters_nb           = NUM_COUNTERS_NB;
 535                 num_counters_llc          = NUM_COUNTERS_L2;
 536                 amd_nb_pmu.name           = "amd_nb";
 537                 amd_llc_pmu.name          = "amd_l2";
 538                 format_attr_event_df      = format_attr_event;
 539                 format_attr_event_l3      = format_attr_event;
 540                 l3_mask                   = false;
 541         }
 542
 543         amd_nb_pmu.attr_groups  = amd_uncore_attr_groups_df;
 544         amd_llc_pmu.attr_groups = amd_uncore_attr_groups_l3;
 545
 546         if (boot_cpu_has(X86_FEATURE_PERFCTR_NB)) {
 547                 amd_uncore_nb = alloc_percpu(struct amd_uncore *);
 548                 if (!amd_uncore_nb) {
 549                         ret = -ENOMEM;
 550                         goto fail_nb;
 551                 }
 552                 ret = perf_pmu_register(&amd_nb_pmu, amd_nb_pmu.name, -1);
 553                 if (ret)
 554                         goto fail_nb;
 555
 556                 pr_info("%s NB counters detected\n",
 557                         boot_cpu_data.x86_vendor == X86_VENDOR_HYGON ?
 558                                 "HYGON" : "AMD");
 559                 ret = 0;
 560         }
 561
 562         if (boot_cpu_has(X86_FEATURE_PERFCTR_LLC)) {
 563                 amd_uncore_llc = alloc_percpu(struct amd_uncore *);
 564                 if (!amd_uncore_llc) {
 565                         ret = -ENOMEM;
 566                         goto fail_llc;
 567                 }
 568                 ret = perf_pmu_register(&amd_llc_pmu, amd_llc_pmu.name, -1);
 569                 if (ret)
 570                         goto fail_llc;
 571
 572                 pr_info("%s LLC counters detected\n",
 573                         boot_cpu_data.x86_vendor == X86_VENDOR_HYGON ?
 574                                 "HYGON" : "AMD");
 575                 ret = 0;
 576         }
 577
 578         /*
 579          * Install callbacks. Core will call them for each online cpu.
 580          */
 581         if (cpuhp_setup_state(CPUHP_PERF_X86_AMD_UNCORE_PREP,
 582                               "perf/x86/amd/uncore:prepare",
 583                               amd_uncore_cpu_up_prepare, amd_uncore_cpu_dead))
 584                 goto fail_llc;
 585
 586         if (cpuhp_setup_state(CPUHP_AP_PERF_X86_AMD_UNCORE_STARTING,
 587                               "perf/x86/amd/uncore:starting",
 588                               amd_uncore_cpu_starting, NULL))
 589                 goto fail_prep;
 590         if (cpuhp_setup_state(CPUHP_AP_PERF_X86_AMD_UNCORE_ONLINE,
 591                               "perf/x86/amd/uncore:online",
 592                               amd_uncore_cpu_online,
 593                               amd_uncore_cpu_down_prepare))
 594                 goto fail_start;
 595         return 0;
 596
 597 fail_start:
 598         cpuhp_remove_state(CPUHP_AP_PERF_X86_AMD_UNCORE_STARTING);
 599 fail_prep:
 600         cpuhp_remove_state(CPUHP_PERF_X86_AMD_UNCORE_PREP);
 601 fail_llc:
 602         if (boot_cpu_has(X86_FEATURE_PERFCTR_NB))
 603                 perf_pmu_unregister(&amd_nb_pmu);
 604         if (amd_uncore_llc)
 605                 free_percpu(amd_uncore_llc);
 606 fail_nb:
 607         if (amd_uncore_nb)
 608                 free_percpu(amd_uncore_nb);
 609
 610         return ret;
 611 }
 612 device_initcall(amd_uncore_init);