linux/arch/x86/events/amd/core.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2#include <linux/perf_event.h>
   3#include <linux/export.h>
   4#include <linux/types.h>
   5#include <linux/init.h>
   6#include <linux/slab.h>
   7#include <linux/delay.h>
   8#include <asm/apicdef.h>
   9#include <asm/nmi.h>
  10
  11#include "../perf_event.h"
  12
  13static DEFINE_PER_CPU(unsigned int, perf_nmi_counter);
  14
  15static __initconst const u64 amd_hw_cache_event_ids
  16                                [PERF_COUNT_HW_CACHE_MAX]
  17                                [PERF_COUNT_HW_CACHE_OP_MAX]
  18                                [PERF_COUNT_HW_CACHE_RESULT_MAX] =
  19{
  20 [ C(L1D) ] = {
  21        [ C(OP_READ) ] = {
  22                [ C(RESULT_ACCESS) ] = 0x0040, /* Data Cache Accesses        */
  23                [ C(RESULT_MISS)   ] = 0x0141, /* Data Cache Misses          */
  24        },
  25        [ C(OP_WRITE) ] = {
  26                [ C(RESULT_ACCESS) ] = 0,
  27                [ C(RESULT_MISS)   ] = 0,
  28        },
  29        [ C(OP_PREFETCH) ] = {
  30                [ C(RESULT_ACCESS) ] = 0x0267, /* Data Prefetcher :attempts  */
  31                [ C(RESULT_MISS)   ] = 0x0167, /* Data Prefetcher :cancelled */
  32        },
  33 },
  34 [ C(L1I ) ] = {
  35        [ C(OP_READ) ] = {
  36                [ C(RESULT_ACCESS) ] = 0x0080, /* Instruction cache fetches  */
  37                [ C(RESULT_MISS)   ] = 0x0081, /* Instruction cache misses   */
  38        },
  39        [ C(OP_WRITE) ] = {
  40                [ C(RESULT_ACCESS) ] = -1,
  41                [ C(RESULT_MISS)   ] = -1,
  42        },
  43        [ C(OP_PREFETCH) ] = {
  44                [ C(RESULT_ACCESS) ] = 0x014B, /* Prefetch Instructions :Load */
  45                [ C(RESULT_MISS)   ] = 0,
  46        },
  47 },
  48 [ C(LL  ) ] = {
  49        [ C(OP_READ) ] = {
  50                [ C(RESULT_ACCESS) ] = 0x037D, /* Requests to L2 Cache :IC+DC */
  51                [ C(RESULT_MISS)   ] = 0x037E, /* L2 Cache Misses : IC+DC     */
  52        },
  53        [ C(OP_WRITE) ] = {
  54                [ C(RESULT_ACCESS) ] = 0x017F, /* L2 Fill/Writeback           */
  55                [ C(RESULT_MISS)   ] = 0,
  56        },
  57        [ C(OP_PREFETCH) ] = {
  58                [ C(RESULT_ACCESS) ] = 0,
  59                [ C(RESULT_MISS)   ] = 0,
  60        },
  61 },
  62 [ C(DTLB) ] = {
  63        [ C(OP_READ) ] = {
  64                [ C(RESULT_ACCESS) ] = 0x0040, /* Data Cache Accesses        */
  65                [ C(RESULT_MISS)   ] = 0x0746, /* L1_DTLB_AND_L2_DLTB_MISS.ALL */
  66        },
  67        [ C(OP_WRITE) ] = {
  68                [ C(RESULT_ACCESS) ] = 0,
  69                [ C(RESULT_MISS)   ] = 0,
  70        },
  71        [ C(OP_PREFETCH) ] = {
  72                [ C(RESULT_ACCESS) ] = 0,
  73                [ C(RESULT_MISS)   ] = 0,
  74        },
  75 },
  76 [ C(ITLB) ] = {
  77        [ C(OP_READ) ] = {
  78                [ C(RESULT_ACCESS) ] = 0x0080, /* Instruction fecthes        */
  79                [ C(RESULT_MISS)   ] = 0x0385, /* L1_ITLB_AND_L2_ITLB_MISS.ALL */
  80        },
  81        [ C(OP_WRITE) ] = {
  82                [ C(RESULT_ACCESS) ] = -1,
  83                [ C(RESULT_MISS)   ] = -1,
  84        },
  85        [ C(OP_PREFETCH) ] = {
  86                [ C(RESULT_ACCESS) ] = -1,
  87                [ C(RESULT_MISS)   ] = -1,
  88        },
  89 },
  90 [ C(BPU ) ] = {
  91        [ C(OP_READ) ] = {
  92                [ C(RESULT_ACCESS) ] = 0x00c2, /* Retired Branch Instr.      */
  93                [ C(RESULT_MISS)   ] = 0x00c3, /* Retired Mispredicted BI    */
  94        },
  95        [ C(OP_WRITE) ] = {
  96                [ C(RESULT_ACCESS) ] = -1,
  97                [ C(RESULT_MISS)   ] = -1,
  98        },
  99        [ C(OP_PREFETCH) ] = {
 100                [ C(RESULT_ACCESS) ] = -1,
 101                [ C(RESULT_MISS)   ] = -1,
 102        },
 103 },
 104 [ C(NODE) ] = {
 105        [ C(OP_READ) ] = {
 106                [ C(RESULT_ACCESS) ] = 0xb8e9, /* CPU Request to Memory, l+r */
 107                [ C(RESULT_MISS)   ] = 0x98e9, /* CPU Request to Memory, r   */
 108        },
 109        [ C(OP_WRITE) ] = {
 110                [ C(RESULT_ACCESS) ] = -1,
 111                [ C(RESULT_MISS)   ] = -1,
 112        },
 113        [ C(OP_PREFETCH) ] = {
 114                [ C(RESULT_ACCESS) ] = -1,
 115                [ C(RESULT_MISS)   ] = -1,
 116        },
 117 },
 118};
 119
 120static __initconst const u64 amd_hw_cache_event_ids_f17h
 121                                [PERF_COUNT_HW_CACHE_MAX]
 122                                [PERF_COUNT_HW_CACHE_OP_MAX]
 123                                [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
 124[C(L1D)] = {
 125        [C(OP_READ)] = {
 126                [C(RESULT_ACCESS)] = 0x0040, /* Data Cache Accesses */
 127                [C(RESULT_MISS)]   = 0xc860, /* L2$ access from DC Miss */
 128        },
 129        [C(OP_WRITE)] = {
 130                [C(RESULT_ACCESS)] = 0,
 131                [C(RESULT_MISS)]   = 0,
 132        },
 133        [C(OP_PREFETCH)] = {
 134                [C(RESULT_ACCESS)] = 0xff5a, /* h/w prefetch DC Fills */
 135                [C(RESULT_MISS)]   = 0,
 136        },
 137},
 138[C(L1I)] = {
 139        [C(OP_READ)] = {
 140                [C(RESULT_ACCESS)] = 0x0080, /* Instruction cache fetches  */
 141                [C(RESULT_MISS)]   = 0x0081, /* Instruction cache misses   */
 142        },
 143        [C(OP_WRITE)] = {
 144                [C(RESULT_ACCESS)] = -1,
 145                [C(RESULT_MISS)]   = -1,
 146        },
 147        [C(OP_PREFETCH)] = {
 148                [C(RESULT_ACCESS)] = 0,
 149                [C(RESULT_MISS)]   = 0,
 150        },
 151},
 152[C(LL)] = {
 153        [C(OP_READ)] = {
 154                [C(RESULT_ACCESS)] = 0,
 155                [C(RESULT_MISS)]   = 0,
 156        },
 157        [C(OP_WRITE)] = {
 158                [C(RESULT_ACCESS)] = 0,
 159                [C(RESULT_MISS)]   = 0,
 160        },
 161        [C(OP_PREFETCH)] = {
 162                [C(RESULT_ACCESS)] = 0,
 163                [C(RESULT_MISS)]   = 0,
 164        },
 165},
 166[C(DTLB)] = {
 167        [C(OP_READ)] = {
 168                [C(RESULT_ACCESS)] = 0xff45, /* All L2 DTLB accesses */
 169                [C(RESULT_MISS)]   = 0xf045, /* L2 DTLB misses (PT walks) */
 170        },
 171        [C(OP_WRITE)] = {
 172                [C(RESULT_ACCESS)] = 0,
 173                [C(RESULT_MISS)]   = 0,
 174        },
 175        [C(OP_PREFETCH)] = {
 176                [C(RESULT_ACCESS)] = 0,
 177                [C(RESULT_MISS)]   = 0,
 178        },
 179},
 180[C(ITLB)] = {
 181        [C(OP_READ)] = {
 182                [C(RESULT_ACCESS)] = 0x0084, /* L1 ITLB misses, L2 ITLB hits */
 183                [C(RESULT_MISS)]   = 0xff85, /* L1 ITLB misses, L2 misses */
 184        },
 185        [C(OP_WRITE)] = {
 186                [C(RESULT_ACCESS)] = -1,
 187                [C(RESULT_MISS)]   = -1,
 188        },
 189        [C(OP_PREFETCH)] = {
 190                [C(RESULT_ACCESS)] = -1,
 191                [C(RESULT_MISS)]   = -1,
 192        },
 193},
 194[C(BPU)] = {
 195        [C(OP_READ)] = {
 196                [C(RESULT_ACCESS)] = 0x00c2, /* Retired Branch Instr.      */
 197                [C(RESULT_MISS)]   = 0x00c3, /* Retired Mispredicted BI    */
 198        },
 199        [C(OP_WRITE)] = {
 200                [C(RESULT_ACCESS)] = -1,
 201                [C(RESULT_MISS)]   = -1,
 202        },
 203        [C(OP_PREFETCH)] = {
 204                [C(RESULT_ACCESS)] = -1,
 205                [C(RESULT_MISS)]   = -1,
 206        },
 207},
 208[C(NODE)] = {
 209        [C(OP_READ)] = {
 210                [C(RESULT_ACCESS)] = 0,
 211                [C(RESULT_MISS)]   = 0,
 212        },
 213        [C(OP_WRITE)] = {
 214                [C(RESULT_ACCESS)] = -1,
 215                [C(RESULT_MISS)]   = -1,
 216        },
 217        [C(OP_PREFETCH)] = {
 218                [C(RESULT_ACCESS)] = -1,
 219                [C(RESULT_MISS)]   = -1,
 220        },
 221},
 222};
 223
 224/*
 225 * AMD Performance Monitor K7 and later, up to and including Family 16h:
 226 */
 227static const u64 amd_perfmon_event_map[PERF_COUNT_HW_MAX] =
 228{
 229        [PERF_COUNT_HW_CPU_CYCLES]              = 0x0076,
 230        [PERF_COUNT_HW_INSTRUCTIONS]            = 0x00c0,
 231        [PERF_COUNT_HW_CACHE_REFERENCES]        = 0x077d,
 232        [PERF_COUNT_HW_CACHE_MISSES]            = 0x077e,
 233        [PERF_COUNT_HW_BRANCH_INSTRUCTIONS]     = 0x00c2,
 234        [PERF_COUNT_HW_BRANCH_MISSES]           = 0x00c3,
 235        [PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] = 0x00d0, /* "Decoder empty" event */
 236        [PERF_COUNT_HW_STALLED_CYCLES_BACKEND]  = 0x00d1, /* "Dispatch stalls" event */
 237};
 238
 239/*
 240 * AMD Performance Monitor Family 17h and later:
 241 */
 242static const u64 amd_f17h_perfmon_event_map[PERF_COUNT_HW_MAX] =
 243{
 244        [PERF_COUNT_HW_CPU_CYCLES]              = 0x0076,
 245        [PERF_COUNT_HW_INSTRUCTIONS]            = 0x00c0,
 246        [PERF_COUNT_HW_CACHE_REFERENCES]        = 0xff60,
 247        [PERF_COUNT_HW_BRANCH_INSTRUCTIONS]     = 0x00c2,
 248        [PERF_COUNT_HW_BRANCH_MISSES]           = 0x00c3,
 249        [PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] = 0x0287,
 250        [PERF_COUNT_HW_STALLED_CYCLES_BACKEND]  = 0x0187,
 251};
 252
 253static u64 amd_pmu_event_map(int hw_event)
 254{
 255        if (boot_cpu_data.x86 >= 0x17)
 256                return amd_f17h_perfmon_event_map[hw_event];
 257
 258        return amd_perfmon_event_map[hw_event];
 259}
 260
 261/*
 262 * Previously calculated offsets
 263 */
 264static unsigned int event_offsets[X86_PMC_IDX_MAX] __read_mostly;
 265static unsigned int count_offsets[X86_PMC_IDX_MAX] __read_mostly;
 266
 267/*
 268 * Legacy CPUs:
 269 *   4 counters starting at 0xc0010000 each offset by 1
 270 *
 271 * CPUs with core performance counter extensions:
 272 *   6 counters starting at 0xc0010200 each offset by 2
 273 */
 274static inline int amd_pmu_addr_offset(int index, bool eventsel)
 275{
 276        int offset;
 277
 278        if (!index)
 279                return index;
 280
 281        if (eventsel)
 282                offset = event_offsets[index];
 283        else
 284                offset = count_offsets[index];
 285
 286        if (offset)
 287                return offset;
 288
 289        if (!boot_cpu_has(X86_FEATURE_PERFCTR_CORE))
 290                offset = index;
 291        else
 292                offset = index << 1;
 293
 294        if (eventsel)
 295                event_offsets[index] = offset;
 296        else
 297                count_offsets[index] = offset;
 298
 299        return offset;
 300}
 301
 302static int amd_core_hw_config(struct perf_event *event)
 303{
 304        if (event->attr.exclude_host && event->attr.exclude_guest)
 305                /*
 306                 * When HO == GO == 1 the hardware treats that as GO == HO == 0
 307                 * and will count in both modes. We don't want to count in that
 308                 * case so we emulate no-counting by setting US = OS = 0.
 309                 */
 310                event->hw.config &= ~(ARCH_PERFMON_EVENTSEL_USR |
 311                                      ARCH_PERFMON_EVENTSEL_OS);
 312        else if (event->attr.exclude_host)
 313                event->hw.config |= AMD64_EVENTSEL_GUESTONLY;
 314        else if (event->attr.exclude_guest)
 315                event->hw.config |= AMD64_EVENTSEL_HOSTONLY;
 316
 317        return 0;
 318}
 319
 320/*
 321 * AMD64 events are detected based on their event codes.
 322 */
 323static inline unsigned int amd_get_event_code(struct hw_perf_event *hwc)
 324{
 325        return ((hwc->config >> 24) & 0x0f00) | (hwc->config & 0x00ff);
 326}
 327
 328static inline int amd_is_nb_event(struct hw_perf_event *hwc)
 329{
 330        return (hwc->config & 0xe0) == 0xe0;
 331}
 332
 333static inline int amd_has_nb(struct cpu_hw_events *cpuc)
 334{
 335        struct amd_nb *nb = cpuc->amd_nb;
 336
 337        return nb && nb->nb_id != -1;
 338}
 339
 340static int amd_pmu_hw_config(struct perf_event *event)
 341{
 342        int ret;
 343
 344        /* pass precise event sampling to ibs: */
 345        if (event->attr.precise_ip && get_ibs_caps())
 346                return -ENOENT;
 347
 348        if (has_branch_stack(event))
 349                return -EOPNOTSUPP;
 350
 351        ret = x86_pmu_hw_config(event);
 352        if (ret)
 353                return ret;
 354
 355        if (event->attr.type == PERF_TYPE_RAW)
 356                event->hw.config |= event->attr.config & AMD64_RAW_EVENT_MASK;
 357
 358        return amd_core_hw_config(event);
 359}
 360
 361static void __amd_put_nb_event_constraints(struct cpu_hw_events *cpuc,
 362                                           struct perf_event *event)
 363{
 364        struct amd_nb *nb = cpuc->amd_nb;
 365        int i;
 366
 367        /*
 368         * need to scan whole list because event may not have
 369         * been assigned during scheduling
 370         *
 371         * no race condition possible because event can only
 372         * be removed on one CPU at a time AND PMU is disabled
 373         * when we come here
 374         */
 375        for (i = 0; i < x86_pmu.num_counters; i++) {
 376                if (cmpxchg(nb->owners + i, event, NULL) == event)
 377                        break;
 378        }
 379}
 380
 381 /*
 382  * AMD64 NorthBridge events need special treatment because
 383  * counter access needs to be synchronized across all cores
 384  * of a package. Refer to BKDG section 3.12
 385  *
 386  * NB events are events measuring L3 cache, Hypertransport
 387  * traffic. They are identified by an event code >= 0xe00.
 388  * They measure events on the NorthBride which is shared
 389  * by all cores on a package. NB events are counted on a
 390  * shared set of counters. When a NB event is programmed
 391  * in a counter, the data actually comes from a shared
 392  * counter. Thus, access to those counters needs to be
 393  * synchronized.
 394  *
 395  * We implement the synchronization such that no two cores
 396  * can be measuring NB events using the same counters. Thus,
 397  * we maintain a per-NB allocation table. The available slot
 398  * is propagated using the event_constraint structure.
 399  *
 400  * We provide only one choice for each NB event based on
 401  * the fact that only NB events have restrictions. Consequently,
 402  * if a counter is available, there is a guarantee the NB event
 403  * will be assigned to it. If no slot is available, an empty
 404  * constraint is returned and scheduling will eventually fail
 405  * for this event.
 406  *
 407  * Note that all cores attached the same NB compete for the same
 408  * counters to host NB events, this is why we use atomic ops. Some
 409  * multi-chip CPUs may have more than one NB.
 410  *
 411  * Given that resources are allocated (cmpxchg), they must be
 412  * eventually freed for others to use. This is accomplished by
 413  * calling __amd_put_nb_event_constraints()
 414  *
 415  * Non NB events are not impacted by this restriction.
 416  */
 417static struct event_constraint *
 418__amd_get_nb_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event,
 419                               struct event_constraint *c)
 420{
 421        struct hw_perf_event *hwc = &event->hw;
 422        struct amd_nb *nb = cpuc->amd_nb;
 423        struct perf_event *old;
 424        int idx, new = -1;
 425
 426        if (!c)
 427                c = &unconstrained;
 428
 429        if (cpuc->is_fake)
 430                return c;
 431
 432        /*
 433         * detect if already present, if so reuse
 434         *
 435         * cannot merge with actual allocation
 436         * because of possible holes
 437         *
 438         * event can already be present yet not assigned (in hwc->idx)
 439         * because of successive calls to x86_schedule_events() from
 440         * hw_perf_group_sched_in() without hw_perf_enable()
 441         */
 442        for_each_set_bit(idx, c->idxmsk, x86_pmu.num_counters) {
 443                if (new == -1 || hwc->idx == idx)
 444                        /* assign free slot, prefer hwc->idx */
 445                        old = cmpxchg(nb->owners + idx, NULL, event);
 446                else if (nb->owners[idx] == event)
 447                        /* event already present */
 448                        old = event;
 449                else
 450                        continue;
 451
 452                if (old && old != event)
 453                        continue;
 454
 455                /* reassign to this slot */
 456                if (new != -1)
 457                        cmpxchg(nb->owners + new, event, NULL);
 458                new = idx;
 459
 460                /* already present, reuse */
 461                if (old == event)
 462                        break;
 463        }
 464
 465        if (new == -1)
 466                return &emptyconstraint;
 467
 468        return &nb->event_constraints[new];
 469}
 470
 471static struct amd_nb *amd_alloc_nb(int cpu)
 472{
 473        struct amd_nb *nb;
 474        int i;
 475
 476        nb = kzalloc_node(sizeof(struct amd_nb), GFP_KERNEL, cpu_to_node(cpu));
 477        if (!nb)
 478                return NULL;
 479
 480        nb->nb_id = -1;
 481
 482        /*
 483         * initialize all possible NB constraints
 484         */
 485        for (i = 0; i < x86_pmu.num_counters; i++) {
 486                __set_bit(i, nb->event_constraints[i].idxmsk);
 487                nb->event_constraints[i].weight = 1;
 488        }
 489        return nb;
 490}
 491
 492static int amd_pmu_cpu_prepare(int cpu)
 493{
 494        struct cpu_hw_events *cpuc = &per_cpu(cpu_hw_events, cpu);
 495
 496        WARN_ON_ONCE(cpuc->amd_nb);
 497
 498        if (!x86_pmu.amd_nb_constraints)
 499                return 0;
 500
 501        cpuc->amd_nb = amd_alloc_nb(cpu);
 502        if (!cpuc->amd_nb)
 503                return -ENOMEM;
 504
 505        return 0;
 506}
 507
 508static void amd_pmu_cpu_starting(int cpu)
 509{
 510        struct cpu_hw_events *cpuc = &per_cpu(cpu_hw_events, cpu);
 511        void **onln = &cpuc->kfree_on_online[X86_PERF_KFREE_SHARED];
 512        struct amd_nb *nb;
 513        int i, nb_id;
 514
 515        cpuc->perf_ctr_virt_mask = AMD64_EVENTSEL_HOSTONLY;
 516
 517        if (!x86_pmu.amd_nb_constraints)
 518                return;
 519
 520        nb_id = amd_get_nb_id(cpu);
 521        WARN_ON_ONCE(nb_id == BAD_APICID);
 522
 523        for_each_online_cpu(i) {
 524                nb = per_cpu(cpu_hw_events, i).amd_nb;
 525                if (WARN_ON_ONCE(!nb))
 526                        continue;
 527
 528                if (nb->nb_id == nb_id) {
 529                        *onln = cpuc->amd_nb;
 530                        cpuc->amd_nb = nb;
 531                        break;
 532                }
 533        }
 534
 535        cpuc->amd_nb->nb_id = nb_id;
 536        cpuc->amd_nb->refcnt++;
 537}
 538
 539static void amd_pmu_cpu_dead(int cpu)
 540{
 541        struct cpu_hw_events *cpuhw;
 542
 543        if (!x86_pmu.amd_nb_constraints)
 544                return;
 545
 546        cpuhw = &per_cpu(cpu_hw_events, cpu);
 547
 548        if (cpuhw->amd_nb) {
 549                struct amd_nb *nb = cpuhw->amd_nb;
 550
 551                if (nb->nb_id == -1 || --nb->refcnt == 0)
 552                        kfree(nb);
 553
 554                cpuhw->amd_nb = NULL;
 555        }
 556}
 557
 558/*
 559 * When a PMC counter overflows, an NMI is used to process the event and
 560 * reset the counter. NMI latency can result in the counter being updated
 561 * before the NMI can run, which can result in what appear to be spurious
 562 * NMIs. This function is intended to wait for the NMI to run and reset
 563 * the counter to avoid possible unhandled NMI messages.
 564 */
 565#define OVERFLOW_WAIT_COUNT     50
 566
 567static void amd_pmu_wait_on_overflow(int idx)
 568{
 569        unsigned int i;
 570        u64 counter;
 571
 572        /*
 573         * Wait for the counter to be reset if it has overflowed. This loop
 574         * should exit very, very quickly, but just in case, don't wait
 575         * forever...
 576         */
 577        for (i = 0; i < OVERFLOW_WAIT_COUNT; i++) {
 578                rdmsrl(x86_pmu_event_addr(idx), counter);
 579                if (counter & (1ULL << (x86_pmu.cntval_bits - 1)))
 580                        break;
 581
 582                /* Might be in IRQ context, so can't sleep */
 583                udelay(1);
 584        }
 585}
 586
 587static void amd_pmu_disable_all(void)
 588{
 589        struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
 590        int idx;
 591
 592        x86_pmu_disable_all();
 593
 594        /*
 595         * This shouldn't be called from NMI context, but add a safeguard here
 596         * to return, since if we're in NMI context we can't wait for an NMI
 597         * to reset an overflowed counter value.
 598         */
 599        if (in_nmi())
 600                return;
 601
 602        /*
 603         * Check each counter for overflow and wait for it to be reset by the
 604         * NMI if it has overflowed. This relies on the fact that all active
 605         * counters are always enabled when this function is caled and
 606         * ARCH_PERFMON_EVENTSEL_INT is always set.
 607         */
 608        for (idx = 0; idx < x86_pmu.num_counters; idx++) {
 609                if (!test_bit(idx, cpuc->active_mask))
 610                        continue;
 611
 612                amd_pmu_wait_on_overflow(idx);
 613        }
 614}
 615
 616static void amd_pmu_disable_event(struct perf_event *event)
 617{
 618        x86_pmu_disable_event(event);
 619
 620        /*
 621         * This can be called from NMI context (via x86_pmu_stop). The counter
 622         * may have overflowed, but either way, we'll never see it get reset
 623         * by the NMI if we're already in the NMI. And the NMI latency support
 624         * below will take care of any pending NMI that might have been
 625         * generated by the overflow.
 626         */
 627        if (in_nmi())
 628                return;
 629
 630        amd_pmu_wait_on_overflow(event->hw.idx);
 631}
 632
 633/*
 634 * Because of NMI latency, if multiple PMC counters are active or other sources
 635 * of NMIs are received, the perf NMI handler can handle one or more overflowed
 636 * PMC counters outside of the NMI associated with the PMC overflow. If the NMI
 637 * doesn't arrive at the LAPIC in time to become a pending NMI, then the kernel
 638 * back-to-back NMI support won't be active. This PMC handler needs to take into
 639 * account that this can occur, otherwise this could result in unknown NMI
 640 * messages being issued. Examples of this is PMC overflow while in the NMI
 641 * handler when multiple PMCs are active or PMC overflow while handling some
 642 * other source of an NMI.
 643 *
 644 * Attempt to mitigate this by using the number of active PMCs to determine
 645 * whether to return NMI_HANDLED if the perf NMI handler did not handle/reset
 646 * any PMCs. The per-CPU perf_nmi_counter variable is set to a minimum of the
 647 * number of active PMCs or 2. The value of 2 is used in case an NMI does not
 648 * arrive at the LAPIC in time to be collapsed into an already pending NMI.
 649 */
 650static int amd_pmu_handle_irq(struct pt_regs *regs)
 651{
 652        struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
 653        int active, handled;
 654
 655        /*
 656         * Obtain the active count before calling x86_pmu_handle_irq() since
 657         * it is possible that x86_pmu_handle_irq() may make a counter
 658         * inactive (through x86_pmu_stop).
 659         */
 660        active = __bitmap_weight(cpuc->active_mask, X86_PMC_IDX_MAX);
 661
 662        /* Process any counter overflows */
 663        handled = x86_pmu_handle_irq(regs);
 664
 665        /*
 666         * If a counter was handled, record the number of possible remaining
 667         * NMIs that can occur.
 668         */
 669        if (handled) {
 670                this_cpu_write(perf_nmi_counter,
 671                               min_t(unsigned int, 2, active));
 672
 673                return handled;
 674        }
 675
 676        if (!this_cpu_read(perf_nmi_counter))
 677                return NMI_DONE;
 678
 679        this_cpu_dec(perf_nmi_counter);
 680
 681        return NMI_HANDLED;
 682}
 683
 684static struct event_constraint *
 685amd_get_event_constraints(struct cpu_hw_events *cpuc, int idx,
 686                          struct perf_event *event)
 687{
 688        /*
 689         * if not NB event or no NB, then no constraints
 690         */
 691        if (!(amd_has_nb(cpuc) && amd_is_nb_event(&event->hw)))
 692                return &unconstrained;
 693
 694        return __amd_get_nb_event_constraints(cpuc, event, NULL);
 695}
 696
 697static void amd_put_event_constraints(struct cpu_hw_events *cpuc,
 698                                      struct perf_event *event)
 699{
 700        if (amd_has_nb(cpuc) && amd_is_nb_event(&event->hw))
 701                __amd_put_nb_event_constraints(cpuc, event);
 702}
 703
 704PMU_FORMAT_ATTR(event,  "config:0-7,32-35");
 705PMU_FORMAT_ATTR(umask,  "config:8-15"   );
 706PMU_FORMAT_ATTR(edge,   "config:18"     );
 707PMU_FORMAT_ATTR(inv,    "config:23"     );
 708PMU_FORMAT_ATTR(cmask,  "config:24-31"  );
 709
 710static struct attribute *amd_format_attr[] = {
 711        &format_attr_event.attr,
 712        &format_attr_umask.attr,
 713        &format_attr_edge.attr,
 714        &format_attr_inv.attr,
 715        &format_attr_cmask.attr,
 716        NULL,
 717};
 718
 719/* AMD Family 15h */
 720
 721#define AMD_EVENT_TYPE_MASK     0x000000F0ULL
 722
 723#define AMD_EVENT_FP            0x00000000ULL ... 0x00000010ULL
 724#define AMD_EVENT_LS            0x00000020ULL ... 0x00000030ULL
 725#define AMD_EVENT_DC            0x00000040ULL ... 0x00000050ULL
 726#define AMD_EVENT_CU            0x00000060ULL ... 0x00000070ULL
 727#define AMD_EVENT_IC_DE         0x00000080ULL ... 0x00000090ULL
 728#define AMD_EVENT_EX_LS         0x000000C0ULL
 729#define AMD_EVENT_DE            0x000000D0ULL
 730#define AMD_EVENT_NB            0x000000E0ULL ... 0x000000F0ULL
 731
 732/*
 733 * AMD family 15h event code/PMC mappings:
 734 *
 735 * type = event_code & 0x0F0:
 736 *
 737 * 0x000        FP      PERF_CTL[5:3]
 738 * 0x010        FP      PERF_CTL[5:3]
 739 * 0x020        LS      PERF_CTL[5:0]
 740 * 0x030        LS      PERF_CTL[5:0]
 741 * 0x040        DC      PERF_CTL[5:0]
 742 * 0x050        DC      PERF_CTL[5:0]
 743 * 0x060        CU      PERF_CTL[2:0]
 744 * 0x070        CU      PERF_CTL[2:0]
 745 * 0x080        IC/DE   PERF_CTL[2:0]
 746 * 0x090        IC/DE   PERF_CTL[2:0]
 747 * 0x0A0        ---
 748 * 0x0B0        ---
 749 * 0x0C0        EX/LS   PERF_CTL[5:0]
 750 * 0x0D0        DE      PERF_CTL[2:0]
 751 * 0x0E0        NB      NB_PERF_CTL[3:0]
 752 * 0x0F0        NB      NB_PERF_CTL[3:0]
 753 *
 754 * Exceptions:
 755 *
 756 * 0x000        FP      PERF_CTL[3], PERF_CTL[5:3] (*)
 757 * 0x003        FP      PERF_CTL[3]
 758 * 0x004        FP      PERF_CTL[3], PERF_CTL[5:3] (*)
 759 * 0x00B        FP      PERF_CTL[3]
 760 * 0x00D        FP      PERF_CTL[3]
 761 * 0x023        DE      PERF_CTL[2:0]
 762 * 0x02D        LS      PERF_CTL[3]
 763 * 0x02E        LS      PERF_CTL[3,0]
 764 * 0x031        LS      PERF_CTL[2:0] (**)
 765 * 0x043        CU      PERF_CTL[2:0]
 766 * 0x045        CU      PERF_CTL[2:0]
 767 * 0x046        CU      PERF_CTL[2:0]
 768 * 0x054        CU      PERF_CTL[2:0]
 769 * 0x055        CU      PERF_CTL[2:0]
 770 * 0x08F        IC      PERF_CTL[0]
 771 * 0x187        DE      PERF_CTL[0]
 772 * 0x188        DE      PERF_CTL[0]
 773 * 0x0DB        EX      PERF_CTL[5:0]
 774 * 0x0DC        LS      PERF_CTL[5:0]
 775 * 0x0DD        LS      PERF_CTL[5:0]
 776 * 0x0DE        LS      PERF_CTL[5:0]
 777 * 0x0DF        LS      PERF_CTL[5:0]
 778 * 0x1C0        EX      PERF_CTL[5:3]
 779 * 0x1D6        EX      PERF_CTL[5:0]
 780 * 0x1D8        EX      PERF_CTL[5:0]
 781 *
 782 * (*)  depending on the umask all FPU counters may be used
 783 * (**) only one unitmask enabled at a time
 784 */
 785
 786static struct event_constraint amd_f15_PMC0  = EVENT_CONSTRAINT(0, 0x01, 0);
 787static struct event_constraint amd_f15_PMC20 = EVENT_CONSTRAINT(0, 0x07, 0);
 788static struct event_constraint amd_f15_PMC3  = EVENT_CONSTRAINT(0, 0x08, 0);
 789static struct event_constraint amd_f15_PMC30 = EVENT_CONSTRAINT_OVERLAP(0, 0x09, 0);
 790static struct event_constraint amd_f15_PMC50 = EVENT_CONSTRAINT(0, 0x3F, 0);
 791static struct event_constraint amd_f15_PMC53 = EVENT_CONSTRAINT(0, 0x38, 0);
 792
 793static struct event_constraint *
 794amd_get_event_constraints_f15h(struct cpu_hw_events *cpuc, int idx,
 795                               struct perf_event *event)
 796{
 797        struct hw_perf_event *hwc = &event->hw;
 798        unsigned int event_code = amd_get_event_code(hwc);
 799
 800        switch (event_code & AMD_EVENT_TYPE_MASK) {
 801        case AMD_EVENT_FP:
 802                switch (event_code) {
 803                case 0x000:
 804                        if (!(hwc->config & 0x0000F000ULL))
 805                                break;
 806                        if (!(hwc->config & 0x00000F00ULL))
 807                                break;
 808                        return &amd_f15_PMC3;
 809                case 0x004:
 810                        if (hweight_long(hwc->config & ARCH_PERFMON_EVENTSEL_UMASK) <= 1)
 811                                break;
 812                        return &amd_f15_PMC3;
 813                case 0x003:
 814                case 0x00B:
 815                case 0x00D:
 816                        return &amd_f15_PMC3;
 817                }
 818                return &amd_f15_PMC53;
 819        case AMD_EVENT_LS:
 820        case AMD_EVENT_DC:
 821        case AMD_EVENT_EX_LS:
 822                switch (event_code) {
 823                case 0x023:
 824                case 0x043:
 825                case 0x045:
 826                case 0x046:
 827                case 0x054:
 828                case 0x055:
 829                        return &amd_f15_PMC20;
 830                case 0x02D:
 831                        return &amd_f15_PMC3;
 832                case 0x02E:
 833                        return &amd_f15_PMC30;
 834                case 0x031:
 835                        if (hweight_long(hwc->config & ARCH_PERFMON_EVENTSEL_UMASK) <= 1)
 836                                return &amd_f15_PMC20;
 837                        return &emptyconstraint;
 838                case 0x1C0:
 839                        return &amd_f15_PMC53;
 840                default:
 841                        return &amd_f15_PMC50;
 842                }
 843        case AMD_EVENT_CU:
 844        case AMD_EVENT_IC_DE:
 845        case AMD_EVENT_DE:
 846                switch (event_code) {
 847                case 0x08F:
 848                case 0x187:
 849                case 0x188:
 850                        return &amd_f15_PMC0;
 851                case 0x0DB ... 0x0DF:
 852                case 0x1D6:
 853                case 0x1D8:
 854                        return &amd_f15_PMC50;
 855                default:
 856                        return &amd_f15_PMC20;
 857                }
 858        case AMD_EVENT_NB:
 859                /* moved to uncore.c */
 860                return &emptyconstraint;
 861        default:
 862                return &emptyconstraint;
 863        }
 864}
 865
 866static ssize_t amd_event_sysfs_show(char *page, u64 config)
 867{
 868        u64 event = (config & ARCH_PERFMON_EVENTSEL_EVENT) |
 869                    (config & AMD64_EVENTSEL_EVENT) >> 24;
 870
 871        return x86_event_sysfs_show(page, config, event);
 872}
 873
 874static __initconst const struct x86_pmu amd_pmu = {
 875        .name                   = "AMD",
 876        .handle_irq             = amd_pmu_handle_irq,
 877        .disable_all            = amd_pmu_disable_all,
 878        .enable_all             = x86_pmu_enable_all,
 879        .enable                 = x86_pmu_enable_event,
 880        .disable                = amd_pmu_disable_event,
 881        .hw_config              = amd_pmu_hw_config,
 882        .schedule_events        = x86_schedule_events,
 883        .eventsel               = MSR_K7_EVNTSEL0,
 884        .perfctr                = MSR_K7_PERFCTR0,
 885        .addr_offset            = amd_pmu_addr_offset,
 886        .event_map              = amd_pmu_event_map,
 887        .max_events             = ARRAY_SIZE(amd_perfmon_event_map),
 888        .num_counters           = AMD64_NUM_COUNTERS,
 889        .cntval_bits            = 48,
 890        .cntval_mask            = (1ULL << 48) - 1,
 891        .apic                   = 1,
 892        /* use highest bit to detect overflow */
 893        .max_period             = (1ULL << 47) - 1,
 894        .get_event_constraints  = amd_get_event_constraints,
 895        .put_event_constraints  = amd_put_event_constraints,
 896
 897        .format_attrs           = amd_format_attr,
 898        .events_sysfs_show      = amd_event_sysfs_show,
 899
 900        .cpu_prepare            = amd_pmu_cpu_prepare,
 901        .cpu_starting           = amd_pmu_cpu_starting,
 902        .cpu_dead               = amd_pmu_cpu_dead,
 903
 904        .amd_nb_constraints     = 1,
 905};
 906
 907static int __init amd_core_pmu_init(void)
 908{
 909        if (!boot_cpu_has(X86_FEATURE_PERFCTR_CORE))
 910                return 0;
 911
 912        switch (boot_cpu_data.x86) {
 913        case 0x15:
 914                pr_cont("Fam15h ");
 915                x86_pmu.get_event_constraints = amd_get_event_constraints_f15h;
 916                break;
 917        case 0x17:
 918                pr_cont("Fam17h ");
 919                /*
 920                 * In family 17h, there are no event constraints in the PMC hardware.
 921                 * We fallback to using default amd_get_event_constraints.
 922                 */
 923                break;
 924        case 0x18:
 925                pr_cont("Fam18h ");
 926                /* Using default amd_get_event_constraints. */
 927                break;
 928        default:
 929                pr_err("core perfctr but no constraints; unknown hardware!\n");
 930                return -ENODEV;
 931        }
 932
 933        /*
 934         * If core performance counter extensions exists, we must use
 935         * MSR_F15H_PERF_CTL/MSR_F15H_PERF_CTR msrs. See also
 936         * amd_pmu_addr_offset().
 937         */
 938        x86_pmu.eventsel        = MSR_F15H_PERF_CTL;
 939        x86_pmu.perfctr         = MSR_F15H_PERF_CTR;
 940        x86_pmu.num_counters    = AMD64_NUM_COUNTERS_CORE;
 941        /*
 942         * AMD Core perfctr has separate MSRs for the NB events, see
 943         * the amd/uncore.c driver.
 944         */
 945        x86_pmu.amd_nb_constraints = 0;
 946
 947        pr_cont("core perfctr, ");
 948        return 0;
 949}
 950
 951__init int amd_pmu_init(void)
 952{
 953        int ret;
 954
 955        /* Performance-monitoring supported from K7 and later: */
 956        if (boot_cpu_data.x86 < 6)
 957                return -ENODEV;
 958
 959        x86_pmu = amd_pmu;
 960
 961        ret = amd_core_pmu_init();
 962        if (ret)
 963                return ret;
 964
 965        if (num_possible_cpus() == 1) {
 966                /*
 967                 * No point in allocating data structures to serialize
 968                 * against other CPUs, when there is only the one CPU.
 969                 */
 970                x86_pmu.amd_nb_constraints = 0;
 971        }
 972
 973        if (boot_cpu_data.x86 >= 0x17)
 974                memcpy(hw_cache_event_ids, amd_hw_cache_event_ids_f17h, sizeof(hw_cache_event_ids));
 975        else
 976                memcpy(hw_cache_event_ids, amd_hw_cache_event_ids, sizeof(hw_cache_event_ids));
 977
 978        return 0;
 979}
 980
 981void amd_pmu_enable_virt(void)
 982{
 983        struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
 984
 985        cpuc->perf_ctr_virt_mask = 0;
 986
 987        /* Reload all events */
 988        amd_pmu_disable_all();
 989        x86_pmu_enable_all(0);
 990}
 991EXPORT_SYMBOL_GPL(amd_pmu_enable_virt);
 992
 993void amd_pmu_disable_virt(void)
 994{
 995        struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
 996
 997        /*
 998         * We only mask out the Host-only bit so that host-only counting works
 999         * when SVM is disabled. If someone sets up a guest-only counter when
1000         * SVM is disabled the Guest-only bits still gets set and the counter
1001         * will not count anything.
1002         */
1003        cpuc->perf_ctr_virt_mask = AMD64_EVENTSEL_HOSTONLY;
1004
1005        /* Reload all events */
1006        amd_pmu_disable_all();
1007        x86_pmu_enable_all(0);
1008}
1009EXPORT_SYMBOL_GPL(amd_pmu_disable_virt);
1010