| 1 | /* |
| 2 | * Performance events x86 architecture code |
| 3 | * |
| 4 | * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de> |
| 5 | * Copyright (C) 2008-2009 Red Hat, Inc., Ingo Molnar |
| 6 | * Copyright (C) 2009 Jaswinder Singh Rajput |
| 7 | * Copyright (C) 2009 Advanced Micro Devices, Inc., Robert Richter |
| 8 | * Copyright (C) 2008-2009 Red Hat, Inc., Peter Zijlstra |
| 9 | * Copyright (C) 2009 Intel Corporation, <markus.t.metzger@intel.com> |
| 10 | * Copyright (C) 2009 Google, Inc., Stephane Eranian |
| 11 | * |
| 12 | * For licencing details see kernel-base/COPYING |
| 13 | */ |
| 14 | |
| 15 | #include <linux/perf_event.h> |
| 16 | #include <linux/capability.h> |
| 17 | #include <linux/notifier.h> |
| 18 | #include <linux/hardirq.h> |
| 19 | #include <linux/kprobes.h> |
| 20 | #include <linux/module.h> |
| 21 | #include <linux/kdebug.h> |
| 22 | #include <linux/sched.h> |
| 23 | #include <linux/uaccess.h> |
| 24 | #include <linux/slab.h> |
| 25 | #include <linux/cpu.h> |
| 26 | #include <linux/bitops.h> |
| 27 | #include <linux/device.h> |
| 28 | |
| 29 | #include <asm/apic.h> |
| 30 | #include <asm/stacktrace.h> |
| 31 | #include <asm/nmi.h> |
| 32 | #include <asm/smp.h> |
| 33 | #include <asm/alternative.h> |
| 34 | #include <asm/mmu_context.h> |
| 35 | #include <asm/tlbflush.h> |
| 36 | #include <asm/timer.h> |
| 37 | #include <asm/desc.h> |
| 38 | #include <asm/ldt.h> |
| 39 | |
| 40 | #include "perf_event.h" |
| 41 | |
| 42 | struct x86_pmu x86_pmu __read_mostly; |
| 43 | |
| 44 | DEFINE_PER_CPU(struct cpu_hw_events, cpu_hw_events) = { |
| 45 | .enabled = 1, |
| 46 | }; |
| 47 | |
| 48 | struct static_key rdpmc_always_available = STATIC_KEY_INIT_FALSE; |
| 49 | |
| 50 | u64 __read_mostly hw_cache_event_ids |
| 51 | [PERF_COUNT_HW_CACHE_MAX] |
| 52 | [PERF_COUNT_HW_CACHE_OP_MAX] |
| 53 | [PERF_COUNT_HW_CACHE_RESULT_MAX]; |
| 54 | u64 __read_mostly hw_cache_extra_regs |
| 55 | [PERF_COUNT_HW_CACHE_MAX] |
| 56 | [PERF_COUNT_HW_CACHE_OP_MAX] |
| 57 | [PERF_COUNT_HW_CACHE_RESULT_MAX]; |
| 58 | |
| 59 | /* |
| 60 | * Propagate event elapsed time into the generic event. |
| 61 | * Can only be executed on the CPU where the event is active. |
| 62 | * Returns the delta events processed. |
| 63 | */ |
| 64 | u64 x86_perf_event_update(struct perf_event *event) |
| 65 | { |
| 66 | struct hw_perf_event *hwc = &event->hw; |
| 67 | int shift = 64 - x86_pmu.cntval_bits; |
| 68 | u64 prev_raw_count, new_raw_count; |
| 69 | int idx = hwc->idx; |
| 70 | s64 delta; |
| 71 | |
| 72 | if (idx == INTEL_PMC_IDX_FIXED_BTS) |
| 73 | return 0; |
| 74 | |
| 75 | /* |
| 76 | * Careful: an NMI might modify the previous event value. |
| 77 | * |
| 78 | * Our tactic to handle this is to first atomically read and |
| 79 | * exchange a new raw count - then add that new-prev delta |
| 80 | * count to the generic event atomically: |
| 81 | */ |
| 82 | again: |
| 83 | prev_raw_count = local64_read(&hwc->prev_count); |
| 84 | rdpmcl(hwc->event_base_rdpmc, new_raw_count); |
| 85 | |
| 86 | if (local64_cmpxchg(&hwc->prev_count, prev_raw_count, |
| 87 | new_raw_count) != prev_raw_count) |
| 88 | goto again; |
| 89 | |
| 90 | /* |
| 91 | * Now we have the new raw value and have updated the prev |
| 92 | * timestamp already. We can now calculate the elapsed delta |
| 93 | * (event-)time and add that to the generic event. |
| 94 | * |
| 95 | * Careful, not all hw sign-extends above the physical width |
| 96 | * of the count. |
| 97 | */ |
| 98 | delta = (new_raw_count << shift) - (prev_raw_count << shift); |
| 99 | delta >>= shift; |
| 100 | |
| 101 | local64_add(delta, &event->count); |
| 102 | local64_sub(delta, &hwc->period_left); |
| 103 | |
| 104 | return new_raw_count; |
| 105 | } |
| 106 | |
| 107 | /* |
| 108 | * Find and validate any extra registers to set up. |
| 109 | */ |
| 110 | static int x86_pmu_extra_regs(u64 config, struct perf_event *event) |
| 111 | { |
| 112 | struct hw_perf_event_extra *reg; |
| 113 | struct extra_reg *er; |
| 114 | |
| 115 | reg = &event->hw.extra_reg; |
| 116 | |
| 117 | if (!x86_pmu.extra_regs) |
| 118 | return 0; |
| 119 | |
| 120 | for (er = x86_pmu.extra_regs; er->msr; er++) { |
| 121 | if (er->event != (config & er->config_mask)) |
| 122 | continue; |
| 123 | if (event->attr.config1 & ~er->valid_mask) |
| 124 | return -EINVAL; |
| 125 | /* Check if the extra msrs can be safely accessed*/ |
| 126 | if (!er->extra_msr_access) |
| 127 | return -ENXIO; |
| 128 | |
| 129 | reg->idx = er->idx; |
| 130 | reg->config = event->attr.config1; |
| 131 | reg->reg = er->msr; |
| 132 | break; |
| 133 | } |
| 134 | return 0; |
| 135 | } |
| 136 | |
| 137 | static atomic_t active_events; |
| 138 | static atomic_t pmc_refcount; |
| 139 | static DEFINE_MUTEX(pmc_reserve_mutex); |
| 140 | |
| 141 | #ifdef CONFIG_X86_LOCAL_APIC |
| 142 | |
| 143 | static bool reserve_pmc_hardware(void) |
| 144 | { |
| 145 | int i; |
| 146 | |
| 147 | for (i = 0; i < x86_pmu.num_counters; i++) { |
| 148 | if (!reserve_perfctr_nmi(x86_pmu_event_addr(i))) |
| 149 | goto perfctr_fail; |
| 150 | } |
| 151 | |
| 152 | for (i = 0; i < x86_pmu.num_counters; i++) { |
| 153 | if (!reserve_evntsel_nmi(x86_pmu_config_addr(i))) |
| 154 | goto eventsel_fail; |
| 155 | } |
| 156 | |
| 157 | return true; |
| 158 | |
| 159 | eventsel_fail: |
| 160 | for (i--; i >= 0; i--) |
| 161 | release_evntsel_nmi(x86_pmu_config_addr(i)); |
| 162 | |
| 163 | i = x86_pmu.num_counters; |
| 164 | |
| 165 | perfctr_fail: |
| 166 | for (i--; i >= 0; i--) |
| 167 | release_perfctr_nmi(x86_pmu_event_addr(i)); |
| 168 | |
| 169 | return false; |
| 170 | } |
| 171 | |
| 172 | static void release_pmc_hardware(void) |
| 173 | { |
| 174 | int i; |
| 175 | |
| 176 | for (i = 0; i < x86_pmu.num_counters; i++) { |
| 177 | release_perfctr_nmi(x86_pmu_event_addr(i)); |
| 178 | release_evntsel_nmi(x86_pmu_config_addr(i)); |
| 179 | } |
| 180 | } |
| 181 | |
| 182 | #else |
| 183 | |
| 184 | static bool reserve_pmc_hardware(void) { return true; } |
| 185 | static void release_pmc_hardware(void) {} |
| 186 | |
| 187 | #endif |
| 188 | |
| 189 | static bool check_hw_exists(void) |
| 190 | { |
| 191 | u64 val, val_fail, val_new= ~0; |
| 192 | int i, reg, reg_fail, ret = 0; |
| 193 | int bios_fail = 0; |
| 194 | int reg_safe = -1; |
| 195 | |
| 196 | /* |
| 197 | * Check to see if the BIOS enabled any of the counters, if so |
| 198 | * complain and bail. |
| 199 | */ |
| 200 | for (i = 0; i < x86_pmu.num_counters; i++) { |
| 201 | reg = x86_pmu_config_addr(i); |
| 202 | ret = rdmsrl_safe(reg, &val); |
| 203 | if (ret) |
| 204 | goto msr_fail; |
| 205 | if (val & ARCH_PERFMON_EVENTSEL_ENABLE) { |
| 206 | bios_fail = 1; |
| 207 | val_fail = val; |
| 208 | reg_fail = reg; |
| 209 | } else { |
| 210 | reg_safe = i; |
| 211 | } |
| 212 | } |
| 213 | |
| 214 | if (x86_pmu.num_counters_fixed) { |
| 215 | reg = MSR_ARCH_PERFMON_FIXED_CTR_CTRL; |
| 216 | ret = rdmsrl_safe(reg, &val); |
| 217 | if (ret) |
| 218 | goto msr_fail; |
| 219 | for (i = 0; i < x86_pmu.num_counters_fixed; i++) { |
| 220 | if (val & (0x03 << i*4)) { |
| 221 | bios_fail = 1; |
| 222 | val_fail = val; |
| 223 | reg_fail = reg; |
| 224 | } |
| 225 | } |
| 226 | } |
| 227 | |
| 228 | /* |
| 229 | * If all the counters are enabled, the below test will always |
| 230 | * fail. The tools will also become useless in this scenario. |
| 231 | * Just fail and disable the hardware counters. |
| 232 | */ |
| 233 | |
| 234 | if (reg_safe == -1) { |
| 235 | reg = reg_safe; |
| 236 | goto msr_fail; |
| 237 | } |
| 238 | |
| 239 | /* |
| 240 | * Read the current value, change it and read it back to see if it |
| 241 | * matches, this is needed to detect certain hardware emulators |
| 242 | * (qemu/kvm) that don't trap on the MSR access and always return 0s. |
| 243 | */ |
| 244 | reg = x86_pmu_event_addr(reg_safe); |
| 245 | if (rdmsrl_safe(reg, &val)) |
| 246 | goto msr_fail; |
| 247 | val ^= 0xffffUL; |
| 248 | ret = wrmsrl_safe(reg, val); |
| 249 | ret |= rdmsrl_safe(reg, &val_new); |
| 250 | if (ret || val != val_new) |
| 251 | goto msr_fail; |
| 252 | |
| 253 | /* |
| 254 | * We still allow the PMU driver to operate: |
| 255 | */ |
| 256 | if (bios_fail) { |
| 257 | pr_cont("Broken BIOS detected, complain to your hardware vendor.\n"); |
| 258 | pr_err(FW_BUG "the BIOS has corrupted hw-PMU resources (MSR %x is %Lx)\n", |
| 259 | reg_fail, val_fail); |
| 260 | } |
| 261 | |
| 262 | return true; |
| 263 | |
| 264 | msr_fail: |
| 265 | pr_cont("Broken PMU hardware detected, using software events only.\n"); |
| 266 | pr_info("%sFailed to access perfctr msr (MSR %x is %Lx)\n", |
| 267 | boot_cpu_has(X86_FEATURE_HYPERVISOR) ? KERN_INFO : KERN_ERR, |
| 268 | reg, val_new); |
| 269 | |
| 270 | return false; |
| 271 | } |
| 272 | |
| 273 | static void hw_perf_event_destroy(struct perf_event *event) |
| 274 | { |
| 275 | x86_release_hardware(); |
| 276 | atomic_dec(&active_events); |
| 277 | } |
| 278 | |
| 279 | void hw_perf_lbr_event_destroy(struct perf_event *event) |
| 280 | { |
| 281 | hw_perf_event_destroy(event); |
| 282 | |
| 283 | /* undo the lbr/bts event accounting */ |
| 284 | x86_del_exclusive(x86_lbr_exclusive_lbr); |
| 285 | } |
| 286 | |
| 287 | static inline int x86_pmu_initialized(void) |
| 288 | { |
| 289 | return x86_pmu.handle_irq != NULL; |
| 290 | } |
| 291 | |
| 292 | static inline int |
| 293 | set_ext_hw_attr(struct hw_perf_event *hwc, struct perf_event *event) |
| 294 | { |
| 295 | struct perf_event_attr *attr = &event->attr; |
| 296 | unsigned int cache_type, cache_op, cache_result; |
| 297 | u64 config, val; |
| 298 | |
| 299 | config = attr->config; |
| 300 | |
| 301 | cache_type = (config >> 0) & 0xff; |
| 302 | if (cache_type >= PERF_COUNT_HW_CACHE_MAX) |
| 303 | return -EINVAL; |
| 304 | |
| 305 | cache_op = (config >> 8) & 0xff; |
| 306 | if (cache_op >= PERF_COUNT_HW_CACHE_OP_MAX) |
| 307 | return -EINVAL; |
| 308 | |
| 309 | cache_result = (config >> 16) & 0xff; |
| 310 | if (cache_result >= PERF_COUNT_HW_CACHE_RESULT_MAX) |
| 311 | return -EINVAL; |
| 312 | |
| 313 | val = hw_cache_event_ids[cache_type][cache_op][cache_result]; |
| 314 | |
| 315 | if (val == 0) |
| 316 | return -ENOENT; |
| 317 | |
| 318 | if (val == -1) |
| 319 | return -EINVAL; |
| 320 | |
| 321 | hwc->config |= val; |
| 322 | attr->config1 = hw_cache_extra_regs[cache_type][cache_op][cache_result]; |
| 323 | return x86_pmu_extra_regs(val, event); |
| 324 | } |
| 325 | |
| 326 | int x86_reserve_hardware(void) |
| 327 | { |
| 328 | int err = 0; |
| 329 | |
| 330 | if (!atomic_inc_not_zero(&pmc_refcount)) { |
| 331 | mutex_lock(&pmc_reserve_mutex); |
| 332 | if (atomic_read(&pmc_refcount) == 0) { |
| 333 | if (!reserve_pmc_hardware()) |
| 334 | err = -EBUSY; |
| 335 | else |
| 336 | reserve_ds_buffers(); |
| 337 | } |
| 338 | if (!err) |
| 339 | atomic_inc(&pmc_refcount); |
| 340 | mutex_unlock(&pmc_reserve_mutex); |
| 341 | } |
| 342 | |
| 343 | return err; |
| 344 | } |
| 345 | |
| 346 | void x86_release_hardware(void) |
| 347 | { |
| 348 | if (atomic_dec_and_mutex_lock(&pmc_refcount, &pmc_reserve_mutex)) { |
| 349 | release_pmc_hardware(); |
| 350 | release_ds_buffers(); |
| 351 | mutex_unlock(&pmc_reserve_mutex); |
| 352 | } |
| 353 | } |
| 354 | |
| 355 | /* |
| 356 | * Check if we can create event of a certain type (that no conflicting events |
| 357 | * are present). |
| 358 | */ |
| 359 | int x86_add_exclusive(unsigned int what) |
| 360 | { |
| 361 | int i; |
| 362 | |
| 363 | if (!atomic_inc_not_zero(&x86_pmu.lbr_exclusive[what])) { |
| 364 | mutex_lock(&pmc_reserve_mutex); |
| 365 | for (i = 0; i < ARRAY_SIZE(x86_pmu.lbr_exclusive); i++) { |
| 366 | if (i != what && atomic_read(&x86_pmu.lbr_exclusive[i])) |
| 367 | goto fail_unlock; |
| 368 | } |
| 369 | atomic_inc(&x86_pmu.lbr_exclusive[what]); |
| 370 | mutex_unlock(&pmc_reserve_mutex); |
| 371 | } |
| 372 | |
| 373 | atomic_inc(&active_events); |
| 374 | return 0; |
| 375 | |
| 376 | fail_unlock: |
| 377 | mutex_unlock(&pmc_reserve_mutex); |
| 378 | return -EBUSY; |
| 379 | } |
| 380 | |
| 381 | void x86_del_exclusive(unsigned int what) |
| 382 | { |
| 383 | atomic_dec(&x86_pmu.lbr_exclusive[what]); |
| 384 | atomic_dec(&active_events); |
| 385 | } |
| 386 | |
| 387 | int x86_setup_perfctr(struct perf_event *event) |
| 388 | { |
| 389 | struct perf_event_attr *attr = &event->attr; |
| 390 | struct hw_perf_event *hwc = &event->hw; |
| 391 | u64 config; |
| 392 | |
| 393 | if (!is_sampling_event(event)) { |
| 394 | hwc->sample_period = x86_pmu.max_period; |
| 395 | hwc->last_period = hwc->sample_period; |
| 396 | local64_set(&hwc->period_left, hwc->sample_period); |
| 397 | } |
| 398 | |
| 399 | if (attr->type == PERF_TYPE_RAW) |
| 400 | return x86_pmu_extra_regs(event->attr.config, event); |
| 401 | |
| 402 | if (attr->type == PERF_TYPE_HW_CACHE) |
| 403 | return set_ext_hw_attr(hwc, event); |
| 404 | |
| 405 | if (attr->config >= x86_pmu.max_events) |
| 406 | return -EINVAL; |
| 407 | |
| 408 | /* |
| 409 | * The generic map: |
| 410 | */ |
| 411 | config = x86_pmu.event_map(attr->config); |
| 412 | |
| 413 | if (config == 0) |
| 414 | return -ENOENT; |
| 415 | |
| 416 | if (config == -1LL) |
| 417 | return -EINVAL; |
| 418 | |
| 419 | /* |
| 420 | * Branch tracing: |
| 421 | */ |
| 422 | if (attr->config == PERF_COUNT_HW_BRANCH_INSTRUCTIONS && |
| 423 | !attr->freq && hwc->sample_period == 1) { |
| 424 | /* BTS is not supported by this architecture. */ |
| 425 | if (!x86_pmu.bts_active) |
| 426 | return -EOPNOTSUPP; |
| 427 | |
| 428 | /* BTS is currently only allowed for user-mode. */ |
| 429 | if (!attr->exclude_kernel) |
| 430 | return -EOPNOTSUPP; |
| 431 | |
| 432 | /* disallow bts if conflicting events are present */ |
| 433 | if (x86_add_exclusive(x86_lbr_exclusive_lbr)) |
| 434 | return -EBUSY; |
| 435 | |
| 436 | event->destroy = hw_perf_lbr_event_destroy; |
| 437 | } |
| 438 | |
| 439 | hwc->config |= config; |
| 440 | |
| 441 | return 0; |
| 442 | } |
| 443 | |
| 444 | /* |
| 445 | * check that branch_sample_type is compatible with |
| 446 | * settings needed for precise_ip > 1 which implies |
| 447 | * using the LBR to capture ALL taken branches at the |
| 448 | * priv levels of the measurement |
| 449 | */ |
| 450 | static inline int precise_br_compat(struct perf_event *event) |
| 451 | { |
| 452 | u64 m = event->attr.branch_sample_type; |
| 453 | u64 b = 0; |
| 454 | |
| 455 | /* must capture all branches */ |
| 456 | if (!(m & PERF_SAMPLE_BRANCH_ANY)) |
| 457 | return 0; |
| 458 | |
| 459 | m &= PERF_SAMPLE_BRANCH_KERNEL | PERF_SAMPLE_BRANCH_USER; |
| 460 | |
| 461 | if (!event->attr.exclude_user) |
| 462 | b |= PERF_SAMPLE_BRANCH_USER; |
| 463 | |
| 464 | if (!event->attr.exclude_kernel) |
| 465 | b |= PERF_SAMPLE_BRANCH_KERNEL; |
| 466 | |
| 467 | /* |
| 468 | * ignore PERF_SAMPLE_BRANCH_HV, not supported on x86 |
| 469 | */ |
| 470 | |
| 471 | return m == b; |
| 472 | } |
| 473 | |
| 474 | int x86_pmu_hw_config(struct perf_event *event) |
| 475 | { |
| 476 | if (event->attr.precise_ip) { |
| 477 | int precise = 0; |
| 478 | |
| 479 | /* Support for constant skid */ |
| 480 | if (x86_pmu.pebs_active && !x86_pmu.pebs_broken) { |
| 481 | precise++; |
| 482 | |
| 483 | /* Support for IP fixup */ |
| 484 | if (x86_pmu.lbr_nr || x86_pmu.intel_cap.pebs_format >= 2) |
| 485 | precise++; |
| 486 | |
| 487 | if (x86_pmu.pebs_prec_dist) |
| 488 | precise++; |
| 489 | } |
| 490 | |
| 491 | if (event->attr.precise_ip > precise) |
| 492 | return -EOPNOTSUPP; |
| 493 | } |
| 494 | /* |
| 495 | * check that PEBS LBR correction does not conflict with |
| 496 | * whatever the user is asking with attr->branch_sample_type |
| 497 | */ |
| 498 | if (event->attr.precise_ip > 1 && x86_pmu.intel_cap.pebs_format < 2) { |
| 499 | u64 *br_type = &event->attr.branch_sample_type; |
| 500 | |
| 501 | if (has_branch_stack(event)) { |
| 502 | if (!precise_br_compat(event)) |
| 503 | return -EOPNOTSUPP; |
| 504 | |
| 505 | /* branch_sample_type is compatible */ |
| 506 | |
| 507 | } else { |
| 508 | /* |
| 509 | * user did not specify branch_sample_type |
| 510 | * |
| 511 | * For PEBS fixups, we capture all |
| 512 | * the branches at the priv level of the |
| 513 | * event. |
| 514 | */ |
| 515 | *br_type = PERF_SAMPLE_BRANCH_ANY; |
| 516 | |
| 517 | if (!event->attr.exclude_user) |
| 518 | *br_type |= PERF_SAMPLE_BRANCH_USER; |
| 519 | |
| 520 | if (!event->attr.exclude_kernel) |
| 521 | *br_type |= PERF_SAMPLE_BRANCH_KERNEL; |
| 522 | } |
| 523 | } |
| 524 | |
| 525 | if (event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_CALL_STACK) |
| 526 | event->attach_state |= PERF_ATTACH_TASK_DATA; |
| 527 | |
| 528 | /* |
| 529 | * Generate PMC IRQs: |
| 530 | * (keep 'enabled' bit clear for now) |
| 531 | */ |
| 532 | event->hw.config = ARCH_PERFMON_EVENTSEL_INT; |
| 533 | |
| 534 | /* |
| 535 | * Count user and OS events unless requested not to |
| 536 | */ |
| 537 | if (!event->attr.exclude_user) |
| 538 | event->hw.config |= ARCH_PERFMON_EVENTSEL_USR; |
| 539 | if (!event->attr.exclude_kernel) |
| 540 | event->hw.config |= ARCH_PERFMON_EVENTSEL_OS; |
| 541 | |
| 542 | if (event->attr.type == PERF_TYPE_RAW) |
| 543 | event->hw.config |= event->attr.config & X86_RAW_EVENT_MASK; |
| 544 | |
| 545 | if (event->attr.sample_period && x86_pmu.limit_period) { |
| 546 | if (x86_pmu.limit_period(event, event->attr.sample_period) > |
| 547 | event->attr.sample_period) |
| 548 | return -EINVAL; |
| 549 | } |
| 550 | |
| 551 | return x86_setup_perfctr(event); |
| 552 | } |
| 553 | |
| 554 | /* |
| 555 | * Setup the hardware configuration for a given attr_type |
| 556 | */ |
| 557 | static int __x86_pmu_event_init(struct perf_event *event) |
| 558 | { |
| 559 | int err; |
| 560 | |
| 561 | if (!x86_pmu_initialized()) |
| 562 | return -ENODEV; |
| 563 | |
| 564 | err = x86_reserve_hardware(); |
| 565 | if (err) |
| 566 | return err; |
| 567 | |
| 568 | atomic_inc(&active_events); |
| 569 | event->destroy = hw_perf_event_destroy; |
| 570 | |
| 571 | event->hw.idx = -1; |
| 572 | event->hw.last_cpu = -1; |
| 573 | event->hw.last_tag = ~0ULL; |
| 574 | |
| 575 | /* mark unused */ |
| 576 | event->hw.extra_reg.idx = EXTRA_REG_NONE; |
| 577 | event->hw.branch_reg.idx = EXTRA_REG_NONE; |
| 578 | |
| 579 | return x86_pmu.hw_config(event); |
| 580 | } |
| 581 | |
| 582 | void x86_pmu_disable_all(void) |
| 583 | { |
| 584 | struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); |
| 585 | int idx; |
| 586 | |
| 587 | for (idx = 0; idx < x86_pmu.num_counters; idx++) { |
| 588 | u64 val; |
| 589 | |
| 590 | if (!test_bit(idx, cpuc->active_mask)) |
| 591 | continue; |
| 592 | rdmsrl(x86_pmu_config_addr(idx), val); |
| 593 | if (!(val & ARCH_PERFMON_EVENTSEL_ENABLE)) |
| 594 | continue; |
| 595 | val &= ~ARCH_PERFMON_EVENTSEL_ENABLE; |
| 596 | wrmsrl(x86_pmu_config_addr(idx), val); |
| 597 | } |
| 598 | } |
| 599 | |
| 600 | /* |
| 601 | * There may be PMI landing after enabled=0. The PMI hitting could be before or |
| 602 | * after disable_all. |
| 603 | * |
| 604 | * If PMI hits before disable_all, the PMU will be disabled in the NMI handler. |
| 605 | * It will not be re-enabled in the NMI handler again, because enabled=0. After |
| 606 | * handling the NMI, disable_all will be called, which will not change the |
| 607 | * state either. If PMI hits after disable_all, the PMU is already disabled |
| 608 | * before entering NMI handler. The NMI handler will not change the state |
| 609 | * either. |
| 610 | * |
| 611 | * So either situation is harmless. |
| 612 | */ |
| 613 | static void x86_pmu_disable(struct pmu *pmu) |
| 614 | { |
| 615 | struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); |
| 616 | |
| 617 | if (!x86_pmu_initialized()) |
| 618 | return; |
| 619 | |
| 620 | if (!cpuc->enabled) |
| 621 | return; |
| 622 | |
| 623 | cpuc->n_added = 0; |
| 624 | cpuc->enabled = 0; |
| 625 | barrier(); |
| 626 | |
| 627 | x86_pmu.disable_all(); |
| 628 | } |
| 629 | |
| 630 | void x86_pmu_enable_all(int added) |
| 631 | { |
| 632 | struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); |
| 633 | int idx; |
| 634 | |
| 635 | for (idx = 0; idx < x86_pmu.num_counters; idx++) { |
| 636 | struct hw_perf_event *hwc = &cpuc->events[idx]->hw; |
| 637 | |
| 638 | if (!test_bit(idx, cpuc->active_mask)) |
| 639 | continue; |
| 640 | |
| 641 | __x86_pmu_enable_event(hwc, ARCH_PERFMON_EVENTSEL_ENABLE); |
| 642 | } |
| 643 | } |
| 644 | |
| 645 | static struct pmu pmu; |
| 646 | |
| 647 | static inline int is_x86_event(struct perf_event *event) |
| 648 | { |
| 649 | return event->pmu == &pmu; |
| 650 | } |
| 651 | |
| 652 | /* |
| 653 | * Event scheduler state: |
| 654 | * |
| 655 | * Assign events iterating over all events and counters, beginning |
| 656 | * with events with least weights first. Keep the current iterator |
| 657 | * state in struct sched_state. |
| 658 | */ |
| 659 | struct sched_state { |
| 660 | int weight; |
| 661 | int event; /* event index */ |
| 662 | int counter; /* counter index */ |
| 663 | int unassigned; /* number of events to be assigned left */ |
| 664 | int nr_gp; /* number of GP counters used */ |
| 665 | unsigned long used[BITS_TO_LONGS(X86_PMC_IDX_MAX)]; |
| 666 | }; |
| 667 | |
| 668 | /* Total max is X86_PMC_IDX_MAX, but we are O(n!) limited */ |
| 669 | #define SCHED_STATES_MAX 2 |
| 670 | |
| 671 | struct perf_sched { |
| 672 | int max_weight; |
| 673 | int max_events; |
| 674 | int max_gp; |
| 675 | int saved_states; |
| 676 | struct event_constraint **constraints; |
| 677 | struct sched_state state; |
| 678 | struct sched_state saved[SCHED_STATES_MAX]; |
| 679 | }; |
| 680 | |
| 681 | /* |
| 682 | * Initialize interator that runs through all events and counters. |
| 683 | */ |
| 684 | static void perf_sched_init(struct perf_sched *sched, struct event_constraint **constraints, |
| 685 | int num, int wmin, int wmax, int gpmax) |
| 686 | { |
| 687 | int idx; |
| 688 | |
| 689 | memset(sched, 0, sizeof(*sched)); |
| 690 | sched->max_events = num; |
| 691 | sched->max_weight = wmax; |
| 692 | sched->max_gp = gpmax; |
| 693 | sched->constraints = constraints; |
| 694 | |
| 695 | for (idx = 0; idx < num; idx++) { |
| 696 | if (constraints[idx]->weight == wmin) |
| 697 | break; |
| 698 | } |
| 699 | |
| 700 | sched->state.event = idx; /* start with min weight */ |
| 701 | sched->state.weight = wmin; |
| 702 | sched->state.unassigned = num; |
| 703 | } |
| 704 | |
| 705 | static void perf_sched_save_state(struct perf_sched *sched) |
| 706 | { |
| 707 | if (WARN_ON_ONCE(sched->saved_states >= SCHED_STATES_MAX)) |
| 708 | return; |
| 709 | |
| 710 | sched->saved[sched->saved_states] = sched->state; |
| 711 | sched->saved_states++; |
| 712 | } |
| 713 | |
| 714 | static bool perf_sched_restore_state(struct perf_sched *sched) |
| 715 | { |
| 716 | if (!sched->saved_states) |
| 717 | return false; |
| 718 | |
| 719 | sched->saved_states--; |
| 720 | sched->state = sched->saved[sched->saved_states]; |
| 721 | |
| 722 | /* continue with next counter: */ |
| 723 | clear_bit(sched->state.counter++, sched->state.used); |
| 724 | |
| 725 | return true; |
| 726 | } |
| 727 | |
| 728 | /* |
| 729 | * Select a counter for the current event to schedule. Return true on |
| 730 | * success. |
| 731 | */ |
| 732 | static bool __perf_sched_find_counter(struct perf_sched *sched) |
| 733 | { |
| 734 | struct event_constraint *c; |
| 735 | int idx; |
| 736 | |
| 737 | if (!sched->state.unassigned) |
| 738 | return false; |
| 739 | |
| 740 | if (sched->state.event >= sched->max_events) |
| 741 | return false; |
| 742 | |
| 743 | c = sched->constraints[sched->state.event]; |
| 744 | /* Prefer fixed purpose counters */ |
| 745 | if (c->idxmsk64 & (~0ULL << INTEL_PMC_IDX_FIXED)) { |
| 746 | idx = INTEL_PMC_IDX_FIXED; |
| 747 | for_each_set_bit_from(idx, c->idxmsk, X86_PMC_IDX_MAX) { |
| 748 | if (!__test_and_set_bit(idx, sched->state.used)) |
| 749 | goto done; |
| 750 | } |
| 751 | } |
| 752 | |
| 753 | /* Grab the first unused counter starting with idx */ |
| 754 | idx = sched->state.counter; |
| 755 | for_each_set_bit_from(idx, c->idxmsk, INTEL_PMC_IDX_FIXED) { |
| 756 | if (!__test_and_set_bit(idx, sched->state.used)) { |
| 757 | if (sched->state.nr_gp++ >= sched->max_gp) |
| 758 | return false; |
| 759 | |
| 760 | goto done; |
| 761 | } |
| 762 | } |
| 763 | |
| 764 | return false; |
| 765 | |
| 766 | done: |
| 767 | sched->state.counter = idx; |
| 768 | |
| 769 | if (c->overlap) |
| 770 | perf_sched_save_state(sched); |
| 771 | |
| 772 | return true; |
| 773 | } |
| 774 | |
| 775 | static bool perf_sched_find_counter(struct perf_sched *sched) |
| 776 | { |
| 777 | while (!__perf_sched_find_counter(sched)) { |
| 778 | if (!perf_sched_restore_state(sched)) |
| 779 | return false; |
| 780 | } |
| 781 | |
| 782 | return true; |
| 783 | } |
| 784 | |
| 785 | /* |
| 786 | * Go through all unassigned events and find the next one to schedule. |
| 787 | * Take events with the least weight first. Return true on success. |
| 788 | */ |
| 789 | static bool perf_sched_next_event(struct perf_sched *sched) |
| 790 | { |
| 791 | struct event_constraint *c; |
| 792 | |
| 793 | if (!sched->state.unassigned || !--sched->state.unassigned) |
| 794 | return false; |
| 795 | |
| 796 | do { |
| 797 | /* next event */ |
| 798 | sched->state.event++; |
| 799 | if (sched->state.event >= sched->max_events) { |
| 800 | /* next weight */ |
| 801 | sched->state.event = 0; |
| 802 | sched->state.weight++; |
| 803 | if (sched->state.weight > sched->max_weight) |
| 804 | return false; |
| 805 | } |
| 806 | c = sched->constraints[sched->state.event]; |
| 807 | } while (c->weight != sched->state.weight); |
| 808 | |
| 809 | sched->state.counter = 0; /* start with first counter */ |
| 810 | |
| 811 | return true; |
| 812 | } |
| 813 | |
| 814 | /* |
| 815 | * Assign a counter for each event. |
| 816 | */ |
| 817 | int perf_assign_events(struct event_constraint **constraints, int n, |
| 818 | int wmin, int wmax, int gpmax, int *assign) |
| 819 | { |
| 820 | struct perf_sched sched; |
| 821 | |
| 822 | perf_sched_init(&sched, constraints, n, wmin, wmax, gpmax); |
| 823 | |
| 824 | do { |
| 825 | if (!perf_sched_find_counter(&sched)) |
| 826 | break; /* failed */ |
| 827 | if (assign) |
| 828 | assign[sched.state.event] = sched.state.counter; |
| 829 | } while (perf_sched_next_event(&sched)); |
| 830 | |
| 831 | return sched.state.unassigned; |
| 832 | } |
| 833 | EXPORT_SYMBOL_GPL(perf_assign_events); |
| 834 | |
| 835 | int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign) |
| 836 | { |
| 837 | struct event_constraint *c; |
| 838 | unsigned long used_mask[BITS_TO_LONGS(X86_PMC_IDX_MAX)]; |
| 839 | struct perf_event *e; |
| 840 | int i, wmin, wmax, unsched = 0; |
| 841 | struct hw_perf_event *hwc; |
| 842 | |
| 843 | bitmap_zero(used_mask, X86_PMC_IDX_MAX); |
| 844 | |
| 845 | if (x86_pmu.start_scheduling) |
| 846 | x86_pmu.start_scheduling(cpuc); |
| 847 | |
| 848 | for (i = 0, wmin = X86_PMC_IDX_MAX, wmax = 0; i < n; i++) { |
| 849 | cpuc->event_constraint[i] = NULL; |
| 850 | c = x86_pmu.get_event_constraints(cpuc, i, cpuc->event_list[i]); |
| 851 | cpuc->event_constraint[i] = c; |
| 852 | |
| 853 | wmin = min(wmin, c->weight); |
| 854 | wmax = max(wmax, c->weight); |
| 855 | } |
| 856 | |
| 857 | /* |
| 858 | * fastpath, try to reuse previous register |
| 859 | */ |
| 860 | for (i = 0; i < n; i++) { |
| 861 | hwc = &cpuc->event_list[i]->hw; |
| 862 | c = cpuc->event_constraint[i]; |
| 863 | |
| 864 | /* never assigned */ |
| 865 | if (hwc->idx == -1) |
| 866 | break; |
| 867 | |
| 868 | /* constraint still honored */ |
| 869 | if (!test_bit(hwc->idx, c->idxmsk)) |
| 870 | break; |
| 871 | |
| 872 | /* not already used */ |
| 873 | if (test_bit(hwc->idx, used_mask)) |
| 874 | break; |
| 875 | |
| 876 | __set_bit(hwc->idx, used_mask); |
| 877 | if (assign) |
| 878 | assign[i] = hwc->idx; |
| 879 | } |
| 880 | |
| 881 | /* slow path */ |
| 882 | if (i != n) { |
| 883 | int gpmax = x86_pmu.num_counters; |
| 884 | |
| 885 | /* |
| 886 | * Do not allow scheduling of more than half the available |
| 887 | * generic counters. |
| 888 | * |
| 889 | * This helps avoid counter starvation of sibling thread by |
| 890 | * ensuring at most half the counters cannot be in exclusive |
| 891 | * mode. There is no designated counters for the limits. Any |
| 892 | * N/2 counters can be used. This helps with events with |
| 893 | * specific counter constraints. |
| 894 | */ |
| 895 | if (is_ht_workaround_enabled() && !cpuc->is_fake && |
| 896 | READ_ONCE(cpuc->excl_cntrs->exclusive_present)) |
| 897 | gpmax /= 2; |
| 898 | |
| 899 | unsched = perf_assign_events(cpuc->event_constraint, n, wmin, |
| 900 | wmax, gpmax, assign); |
| 901 | } |
| 902 | |
| 903 | /* |
| 904 | * In case of success (unsched = 0), mark events as committed, |
| 905 | * so we do not put_constraint() in case new events are added |
| 906 | * and fail to be scheduled |
| 907 | * |
| 908 | * We invoke the lower level commit callback to lock the resource |
| 909 | * |
| 910 | * We do not need to do all of this in case we are called to |
| 911 | * validate an event group (assign == NULL) |
| 912 | */ |
| 913 | if (!unsched && assign) { |
| 914 | for (i = 0; i < n; i++) { |
| 915 | e = cpuc->event_list[i]; |
| 916 | e->hw.flags |= PERF_X86_EVENT_COMMITTED; |
| 917 | if (x86_pmu.commit_scheduling) |
| 918 | x86_pmu.commit_scheduling(cpuc, i, assign[i]); |
| 919 | } |
| 920 | } else { |
| 921 | for (i = 0; i < n; i++) { |
| 922 | e = cpuc->event_list[i]; |
| 923 | /* |
| 924 | * do not put_constraint() on comitted events, |
| 925 | * because they are good to go |
| 926 | */ |
| 927 | if ((e->hw.flags & PERF_X86_EVENT_COMMITTED)) |
| 928 | continue; |
| 929 | |
| 930 | /* |
| 931 | * release events that failed scheduling |
| 932 | */ |
| 933 | if (x86_pmu.put_event_constraints) |
| 934 | x86_pmu.put_event_constraints(cpuc, e); |
| 935 | } |
| 936 | } |
| 937 | |
| 938 | if (x86_pmu.stop_scheduling) |
| 939 | x86_pmu.stop_scheduling(cpuc); |
| 940 | |
| 941 | return unsched ? -EINVAL : 0; |
| 942 | } |
| 943 | |
| 944 | /* |
| 945 | * dogrp: true if must collect siblings events (group) |
| 946 | * returns total number of events and error code |
| 947 | */ |
| 948 | static int collect_events(struct cpu_hw_events *cpuc, struct perf_event *leader, bool dogrp) |
| 949 | { |
| 950 | struct perf_event *event; |
| 951 | int n, max_count; |
| 952 | |
| 953 | max_count = x86_pmu.num_counters + x86_pmu.num_counters_fixed; |
| 954 | |
| 955 | /* current number of events already accepted */ |
| 956 | n = cpuc->n_events; |
| 957 | |
| 958 | if (is_x86_event(leader)) { |
| 959 | if (n >= max_count) |
| 960 | return -EINVAL; |
| 961 | cpuc->event_list[n] = leader; |
| 962 | n++; |
| 963 | } |
| 964 | if (!dogrp) |
| 965 | return n; |
| 966 | |
| 967 | list_for_each_entry(event, &leader->sibling_list, group_entry) { |
| 968 | if (!is_x86_event(event) || |
| 969 | event->state <= PERF_EVENT_STATE_OFF) |
| 970 | continue; |
| 971 | |
| 972 | if (n >= max_count) |
| 973 | return -EINVAL; |
| 974 | |
| 975 | cpuc->event_list[n] = event; |
| 976 | n++; |
| 977 | } |
| 978 | return n; |
| 979 | } |
| 980 | |
| 981 | static inline void x86_assign_hw_event(struct perf_event *event, |
| 982 | struct cpu_hw_events *cpuc, int i) |
| 983 | { |
| 984 | struct hw_perf_event *hwc = &event->hw; |
| 985 | |
| 986 | hwc->idx = cpuc->assign[i]; |
| 987 | hwc->last_cpu = smp_processor_id(); |
| 988 | hwc->last_tag = ++cpuc->tags[i]; |
| 989 | |
| 990 | if (hwc->idx == INTEL_PMC_IDX_FIXED_BTS) { |
| 991 | hwc->config_base = 0; |
| 992 | hwc->event_base = 0; |
| 993 | } else if (hwc->idx >= INTEL_PMC_IDX_FIXED) { |
| 994 | hwc->config_base = MSR_ARCH_PERFMON_FIXED_CTR_CTRL; |
| 995 | hwc->event_base = MSR_ARCH_PERFMON_FIXED_CTR0 + (hwc->idx - INTEL_PMC_IDX_FIXED); |
| 996 | hwc->event_base_rdpmc = (hwc->idx - INTEL_PMC_IDX_FIXED) | 1<<30; |
| 997 | } else { |
| 998 | hwc->config_base = x86_pmu_config_addr(hwc->idx); |
| 999 | hwc->event_base = x86_pmu_event_addr(hwc->idx); |
| 1000 | hwc->event_base_rdpmc = x86_pmu_rdpmc_index(hwc->idx); |
| 1001 | } |
| 1002 | } |
| 1003 | |
| 1004 | static inline int match_prev_assignment(struct hw_perf_event *hwc, |
| 1005 | struct cpu_hw_events *cpuc, |
| 1006 | int i) |
| 1007 | { |
| 1008 | return hwc->idx == cpuc->assign[i] && |
| 1009 | hwc->last_cpu == smp_processor_id() && |
| 1010 | hwc->last_tag == cpuc->tags[i]; |
| 1011 | } |
| 1012 | |
| 1013 | static void x86_pmu_start(struct perf_event *event, int flags); |
| 1014 | |
| 1015 | static void x86_pmu_enable(struct pmu *pmu) |
| 1016 | { |
| 1017 | struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); |
| 1018 | struct perf_event *event; |
| 1019 | struct hw_perf_event *hwc; |
| 1020 | int i, added = cpuc->n_added; |
| 1021 | |
| 1022 | if (!x86_pmu_initialized()) |
| 1023 | return; |
| 1024 | |
| 1025 | if (cpuc->enabled) |
| 1026 | return; |
| 1027 | |
| 1028 | if (cpuc->n_added) { |
| 1029 | int n_running = cpuc->n_events - cpuc->n_added; |
| 1030 | /* |
| 1031 | * apply assignment obtained either from |
| 1032 | * hw_perf_group_sched_in() or x86_pmu_enable() |
| 1033 | * |
| 1034 | * step1: save events moving to new counters |
| 1035 | */ |
| 1036 | for (i = 0; i < n_running; i++) { |
| 1037 | event = cpuc->event_list[i]; |
| 1038 | hwc = &event->hw; |
| 1039 | |
| 1040 | /* |
| 1041 | * we can avoid reprogramming counter if: |
| 1042 | * - assigned same counter as last time |
| 1043 | * - running on same CPU as last time |
| 1044 | * - no other event has used the counter since |
| 1045 | */ |
| 1046 | if (hwc->idx == -1 || |
| 1047 | match_prev_assignment(hwc, cpuc, i)) |
| 1048 | continue; |
| 1049 | |
| 1050 | /* |
| 1051 | * Ensure we don't accidentally enable a stopped |
| 1052 | * counter simply because we rescheduled. |
| 1053 | */ |
| 1054 | if (hwc->state & PERF_HES_STOPPED) |
| 1055 | hwc->state |= PERF_HES_ARCH; |
| 1056 | |
| 1057 | x86_pmu_stop(event, PERF_EF_UPDATE); |
| 1058 | } |
| 1059 | |
| 1060 | /* |
| 1061 | * step2: reprogram moved events into new counters |
| 1062 | */ |
| 1063 | for (i = 0; i < cpuc->n_events; i++) { |
| 1064 | event = cpuc->event_list[i]; |
| 1065 | hwc = &event->hw; |
| 1066 | |
| 1067 | if (!match_prev_assignment(hwc, cpuc, i)) |
| 1068 | x86_assign_hw_event(event, cpuc, i); |
| 1069 | else if (i < n_running) |
| 1070 | continue; |
| 1071 | |
| 1072 | if (hwc->state & PERF_HES_ARCH) |
| 1073 | continue; |
| 1074 | |
| 1075 | x86_pmu_start(event, PERF_EF_RELOAD); |
| 1076 | } |
| 1077 | cpuc->n_added = 0; |
| 1078 | perf_events_lapic_init(); |
| 1079 | } |
| 1080 | |
| 1081 | cpuc->enabled = 1; |
| 1082 | barrier(); |
| 1083 | |
| 1084 | x86_pmu.enable_all(added); |
| 1085 | } |
| 1086 | |
| 1087 | static DEFINE_PER_CPU(u64 [X86_PMC_IDX_MAX], pmc_prev_left); |
| 1088 | |
| 1089 | /* |
| 1090 | * Set the next IRQ period, based on the hwc->period_left value. |
| 1091 | * To be called with the event disabled in hw: |
| 1092 | */ |
| 1093 | int x86_perf_event_set_period(struct perf_event *event) |
| 1094 | { |
| 1095 | struct hw_perf_event *hwc = &event->hw; |
| 1096 | s64 left = local64_read(&hwc->period_left); |
| 1097 | s64 period = hwc->sample_period; |
| 1098 | int ret = 0, idx = hwc->idx; |
| 1099 | |
| 1100 | if (idx == INTEL_PMC_IDX_FIXED_BTS) |
| 1101 | return 0; |
| 1102 | |
| 1103 | /* |
| 1104 | * If we are way outside a reasonable range then just skip forward: |
| 1105 | */ |
| 1106 | if (unlikely(left <= -period)) { |
| 1107 | left = period; |
| 1108 | local64_set(&hwc->period_left, left); |
| 1109 | hwc->last_period = period; |
| 1110 | ret = 1; |
| 1111 | } |
| 1112 | |
| 1113 | if (unlikely(left <= 0)) { |
| 1114 | left += period; |
| 1115 | local64_set(&hwc->period_left, left); |
| 1116 | hwc->last_period = period; |
| 1117 | ret = 1; |
| 1118 | } |
| 1119 | /* |
| 1120 | * Quirk: certain CPUs dont like it if just 1 hw_event is left: |
| 1121 | */ |
| 1122 | if (unlikely(left < 2)) |
| 1123 | left = 2; |
| 1124 | |
| 1125 | if (left > x86_pmu.max_period) |
| 1126 | left = x86_pmu.max_period; |
| 1127 | |
| 1128 | if (x86_pmu.limit_period) |
| 1129 | left = x86_pmu.limit_period(event, left); |
| 1130 | |
| 1131 | per_cpu(pmc_prev_left[idx], smp_processor_id()) = left; |
| 1132 | |
| 1133 | if (!(hwc->flags & PERF_X86_EVENT_AUTO_RELOAD) || |
| 1134 | local64_read(&hwc->prev_count) != (u64)-left) { |
| 1135 | /* |
| 1136 | * The hw event starts counting from this event offset, |
| 1137 | * mark it to be able to extra future deltas: |
| 1138 | */ |
| 1139 | local64_set(&hwc->prev_count, (u64)-left); |
| 1140 | |
| 1141 | wrmsrl(hwc->event_base, (u64)(-left) & x86_pmu.cntval_mask); |
| 1142 | } |
| 1143 | |
| 1144 | /* |
| 1145 | * Due to erratum on certan cpu we need |
| 1146 | * a second write to be sure the register |
| 1147 | * is updated properly |
| 1148 | */ |
| 1149 | if (x86_pmu.perfctr_second_write) { |
| 1150 | wrmsrl(hwc->event_base, |
| 1151 | (u64)(-left) & x86_pmu.cntval_mask); |
| 1152 | } |
| 1153 | |
| 1154 | perf_event_update_userpage(event); |
| 1155 | |
| 1156 | return ret; |
| 1157 | } |
| 1158 | |
| 1159 | void x86_pmu_enable_event(struct perf_event *event) |
| 1160 | { |
| 1161 | if (__this_cpu_read(cpu_hw_events.enabled)) |
| 1162 | __x86_pmu_enable_event(&event->hw, |
| 1163 | ARCH_PERFMON_EVENTSEL_ENABLE); |
| 1164 | } |
| 1165 | |
| 1166 | /* |
| 1167 | * Add a single event to the PMU. |
| 1168 | * |
| 1169 | * The event is added to the group of enabled events |
| 1170 | * but only if it can be scehduled with existing events. |
| 1171 | */ |
| 1172 | static int x86_pmu_add(struct perf_event *event, int flags) |
| 1173 | { |
| 1174 | struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); |
| 1175 | struct hw_perf_event *hwc; |
| 1176 | int assign[X86_PMC_IDX_MAX]; |
| 1177 | int n, n0, ret; |
| 1178 | |
| 1179 | hwc = &event->hw; |
| 1180 | |
| 1181 | n0 = cpuc->n_events; |
| 1182 | ret = n = collect_events(cpuc, event, false); |
| 1183 | if (ret < 0) |
| 1184 | goto out; |
| 1185 | |
| 1186 | hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED; |
| 1187 | if (!(flags & PERF_EF_START)) |
| 1188 | hwc->state |= PERF_HES_ARCH; |
| 1189 | |
| 1190 | /* |
| 1191 | * If group events scheduling transaction was started, |
| 1192 | * skip the schedulability test here, it will be performed |
| 1193 | * at commit time (->commit_txn) as a whole. |
| 1194 | */ |
| 1195 | if (cpuc->txn_flags & PERF_PMU_TXN_ADD) |
| 1196 | goto done_collect; |
| 1197 | |
| 1198 | ret = x86_pmu.schedule_events(cpuc, n, assign); |
| 1199 | if (ret) |
| 1200 | goto out; |
| 1201 | /* |
| 1202 | * copy new assignment, now we know it is possible |
| 1203 | * will be used by hw_perf_enable() |
| 1204 | */ |
| 1205 | memcpy(cpuc->assign, assign, n*sizeof(int)); |
| 1206 | |
| 1207 | done_collect: |
| 1208 | /* |
| 1209 | * Commit the collect_events() state. See x86_pmu_del() and |
| 1210 | * x86_pmu_*_txn(). |
| 1211 | */ |
| 1212 | cpuc->n_events = n; |
| 1213 | cpuc->n_added += n - n0; |
| 1214 | cpuc->n_txn += n - n0; |
| 1215 | |
| 1216 | ret = 0; |
| 1217 | out: |
| 1218 | return ret; |
| 1219 | } |
| 1220 | |
| 1221 | static void x86_pmu_start(struct perf_event *event, int flags) |
| 1222 | { |
| 1223 | struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); |
| 1224 | int idx = event->hw.idx; |
| 1225 | |
| 1226 | if (WARN_ON_ONCE(!(event->hw.state & PERF_HES_STOPPED))) |
| 1227 | return; |
| 1228 | |
| 1229 | if (WARN_ON_ONCE(idx == -1)) |
| 1230 | return; |
| 1231 | |
| 1232 | if (flags & PERF_EF_RELOAD) { |
| 1233 | WARN_ON_ONCE(!(event->hw.state & PERF_HES_UPTODATE)); |
| 1234 | x86_perf_event_set_period(event); |
| 1235 | } |
| 1236 | |
| 1237 | event->hw.state = 0; |
| 1238 | |
| 1239 | cpuc->events[idx] = event; |
| 1240 | __set_bit(idx, cpuc->active_mask); |
| 1241 | __set_bit(idx, cpuc->running); |
| 1242 | x86_pmu.enable(event); |
| 1243 | perf_event_update_userpage(event); |
| 1244 | } |
| 1245 | |
| 1246 | void perf_event_print_debug(void) |
| 1247 | { |
| 1248 | u64 ctrl, status, overflow, pmc_ctrl, pmc_count, prev_left, fixed; |
| 1249 | u64 pebs, debugctl; |
| 1250 | struct cpu_hw_events *cpuc; |
| 1251 | unsigned long flags; |
| 1252 | int cpu, idx; |
| 1253 | |
| 1254 | if (!x86_pmu.num_counters) |
| 1255 | return; |
| 1256 | |
| 1257 | local_irq_save(flags); |
| 1258 | |
| 1259 | cpu = smp_processor_id(); |
| 1260 | cpuc = &per_cpu(cpu_hw_events, cpu); |
| 1261 | |
| 1262 | if (x86_pmu.version >= 2) { |
| 1263 | rdmsrl(MSR_CORE_PERF_GLOBAL_CTRL, ctrl); |
| 1264 | rdmsrl(MSR_CORE_PERF_GLOBAL_STATUS, status); |
| 1265 | rdmsrl(MSR_CORE_PERF_GLOBAL_OVF_CTRL, overflow); |
| 1266 | rdmsrl(MSR_ARCH_PERFMON_FIXED_CTR_CTRL, fixed); |
| 1267 | |
| 1268 | pr_info("\n"); |
| 1269 | pr_info("CPU#%d: ctrl: %016llx\n", cpu, ctrl); |
| 1270 | pr_info("CPU#%d: status: %016llx\n", cpu, status); |
| 1271 | pr_info("CPU#%d: overflow: %016llx\n", cpu, overflow); |
| 1272 | pr_info("CPU#%d: fixed: %016llx\n", cpu, fixed); |
| 1273 | if (x86_pmu.pebs_constraints) { |
| 1274 | rdmsrl(MSR_IA32_PEBS_ENABLE, pebs); |
| 1275 | pr_info("CPU#%d: pebs: %016llx\n", cpu, pebs); |
| 1276 | } |
| 1277 | if (x86_pmu.lbr_nr) { |
| 1278 | rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctl); |
| 1279 | pr_info("CPU#%d: debugctl: %016llx\n", cpu, debugctl); |
| 1280 | } |
| 1281 | } |
| 1282 | pr_info("CPU#%d: active: %016llx\n", cpu, *(u64 *)cpuc->active_mask); |
| 1283 | |
| 1284 | for (idx = 0; idx < x86_pmu.num_counters; idx++) { |
| 1285 | rdmsrl(x86_pmu_config_addr(idx), pmc_ctrl); |
| 1286 | rdmsrl(x86_pmu_event_addr(idx), pmc_count); |
| 1287 | |
| 1288 | prev_left = per_cpu(pmc_prev_left[idx], cpu); |
| 1289 | |
| 1290 | pr_info("CPU#%d: gen-PMC%d ctrl: %016llx\n", |
| 1291 | cpu, idx, pmc_ctrl); |
| 1292 | pr_info("CPU#%d: gen-PMC%d count: %016llx\n", |
| 1293 | cpu, idx, pmc_count); |
| 1294 | pr_info("CPU#%d: gen-PMC%d left: %016llx\n", |
| 1295 | cpu, idx, prev_left); |
| 1296 | } |
| 1297 | for (idx = 0; idx < x86_pmu.num_counters_fixed; idx++) { |
| 1298 | rdmsrl(MSR_ARCH_PERFMON_FIXED_CTR0 + idx, pmc_count); |
| 1299 | |
| 1300 | pr_info("CPU#%d: fixed-PMC%d count: %016llx\n", |
| 1301 | cpu, idx, pmc_count); |
| 1302 | } |
| 1303 | local_irq_restore(flags); |
| 1304 | } |
| 1305 | |
| 1306 | void x86_pmu_stop(struct perf_event *event, int flags) |
| 1307 | { |
| 1308 | struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); |
| 1309 | struct hw_perf_event *hwc = &event->hw; |
| 1310 | |
| 1311 | if (__test_and_clear_bit(hwc->idx, cpuc->active_mask)) { |
| 1312 | x86_pmu.disable(event); |
| 1313 | cpuc->events[hwc->idx] = NULL; |
| 1314 | WARN_ON_ONCE(hwc->state & PERF_HES_STOPPED); |
| 1315 | hwc->state |= PERF_HES_STOPPED; |
| 1316 | } |
| 1317 | |
| 1318 | if ((flags & PERF_EF_UPDATE) && !(hwc->state & PERF_HES_UPTODATE)) { |
| 1319 | /* |
| 1320 | * Drain the remaining delta count out of a event |
| 1321 | * that we are disabling: |
| 1322 | */ |
| 1323 | x86_perf_event_update(event); |
| 1324 | hwc->state |= PERF_HES_UPTODATE; |
| 1325 | } |
| 1326 | } |
| 1327 | |
| 1328 | static void x86_pmu_del(struct perf_event *event, int flags) |
| 1329 | { |
| 1330 | struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); |
| 1331 | int i; |
| 1332 | |
| 1333 | /* |
| 1334 | * event is descheduled |
| 1335 | */ |
| 1336 | event->hw.flags &= ~PERF_X86_EVENT_COMMITTED; |
| 1337 | |
| 1338 | /* |
| 1339 | * If we're called during a txn, we don't need to do anything. |
| 1340 | * The events never got scheduled and ->cancel_txn will truncate |
| 1341 | * the event_list. |
| 1342 | * |
| 1343 | * XXX assumes any ->del() called during a TXN will only be on |
| 1344 | * an event added during that same TXN. |
| 1345 | */ |
| 1346 | if (cpuc->txn_flags & PERF_PMU_TXN_ADD) |
| 1347 | return; |
| 1348 | |
| 1349 | /* |
| 1350 | * Not a TXN, therefore cleanup properly. |
| 1351 | */ |
| 1352 | x86_pmu_stop(event, PERF_EF_UPDATE); |
| 1353 | |
| 1354 | for (i = 0; i < cpuc->n_events; i++) { |
| 1355 | if (event == cpuc->event_list[i]) |
| 1356 | break; |
| 1357 | } |
| 1358 | |
| 1359 | if (WARN_ON_ONCE(i == cpuc->n_events)) /* called ->del() without ->add() ? */ |
| 1360 | return; |
| 1361 | |
| 1362 | /* If we have a newly added event; make sure to decrease n_added. */ |
| 1363 | if (i >= cpuc->n_events - cpuc->n_added) |
| 1364 | --cpuc->n_added; |
| 1365 | |
| 1366 | if (x86_pmu.put_event_constraints) |
| 1367 | x86_pmu.put_event_constraints(cpuc, event); |
| 1368 | |
| 1369 | /* Delete the array entry. */ |
| 1370 | while (++i < cpuc->n_events) { |
| 1371 | cpuc->event_list[i-1] = cpuc->event_list[i]; |
| 1372 | cpuc->event_constraint[i-1] = cpuc->event_constraint[i]; |
| 1373 | } |
| 1374 | --cpuc->n_events; |
| 1375 | |
| 1376 | perf_event_update_userpage(event); |
| 1377 | } |
| 1378 | |
| 1379 | int x86_pmu_handle_irq(struct pt_regs *regs) |
| 1380 | { |
| 1381 | struct perf_sample_data data; |
| 1382 | struct cpu_hw_events *cpuc; |
| 1383 | struct perf_event *event; |
| 1384 | int idx, handled = 0; |
| 1385 | u64 val; |
| 1386 | |
| 1387 | cpuc = this_cpu_ptr(&cpu_hw_events); |
| 1388 | |
| 1389 | /* |
| 1390 | * Some chipsets need to unmask the LVTPC in a particular spot |
| 1391 | * inside the nmi handler. As a result, the unmasking was pushed |
| 1392 | * into all the nmi handlers. |
| 1393 | * |
| 1394 | * This generic handler doesn't seem to have any issues where the |
| 1395 | * unmasking occurs so it was left at the top. |
| 1396 | */ |
| 1397 | apic_write(APIC_LVTPC, APIC_DM_NMI); |
| 1398 | |
| 1399 | for (idx = 0; idx < x86_pmu.num_counters; idx++) { |
| 1400 | if (!test_bit(idx, cpuc->active_mask)) { |
| 1401 | /* |
| 1402 | * Though we deactivated the counter some cpus |
| 1403 | * might still deliver spurious interrupts still |
| 1404 | * in flight. Catch them: |
| 1405 | */ |
| 1406 | if (__test_and_clear_bit(idx, cpuc->running)) |
| 1407 | handled++; |
| 1408 | continue; |
| 1409 | } |
| 1410 | |
| 1411 | event = cpuc->events[idx]; |
| 1412 | |
| 1413 | val = x86_perf_event_update(event); |
| 1414 | if (val & (1ULL << (x86_pmu.cntval_bits - 1))) |
| 1415 | continue; |
| 1416 | |
| 1417 | /* |
| 1418 | * event overflow |
| 1419 | */ |
| 1420 | handled++; |
| 1421 | perf_sample_data_init(&data, 0, event->hw.last_period); |
| 1422 | |
| 1423 | if (!x86_perf_event_set_period(event)) |
| 1424 | continue; |
| 1425 | |
| 1426 | if (perf_event_overflow(event, &data, regs)) |
| 1427 | x86_pmu_stop(event, 0); |
| 1428 | } |
| 1429 | |
| 1430 | if (handled) |
| 1431 | inc_irq_stat(apic_perf_irqs); |
| 1432 | |
| 1433 | return handled; |
| 1434 | } |
| 1435 | |
| 1436 | void perf_events_lapic_init(void) |
| 1437 | { |
| 1438 | if (!x86_pmu.apic || !x86_pmu_initialized()) |
| 1439 | return; |
| 1440 | |
| 1441 | /* |
| 1442 | * Always use NMI for PMU |
| 1443 | */ |
| 1444 | apic_write(APIC_LVTPC, APIC_DM_NMI); |
| 1445 | } |
| 1446 | |
| 1447 | static int |
| 1448 | perf_event_nmi_handler(unsigned int cmd, struct pt_regs *regs) |
| 1449 | { |
| 1450 | u64 start_clock; |
| 1451 | u64 finish_clock; |
| 1452 | int ret; |
| 1453 | |
| 1454 | /* |
| 1455 | * All PMUs/events that share this PMI handler should make sure to |
| 1456 | * increment active_events for their events. |
| 1457 | */ |
| 1458 | if (!atomic_read(&active_events)) |
| 1459 | return NMI_DONE; |
| 1460 | |
| 1461 | start_clock = sched_clock(); |
| 1462 | ret = x86_pmu.handle_irq(regs); |
| 1463 | finish_clock = sched_clock(); |
| 1464 | |
| 1465 | perf_sample_event_took(finish_clock - start_clock); |
| 1466 | |
| 1467 | return ret; |
| 1468 | } |
| 1469 | NOKPROBE_SYMBOL(perf_event_nmi_handler); |
| 1470 | |
| 1471 | struct event_constraint emptyconstraint; |
| 1472 | struct event_constraint unconstrained; |
| 1473 | |
| 1474 | static int |
| 1475 | x86_pmu_notifier(struct notifier_block *self, unsigned long action, void *hcpu) |
| 1476 | { |
| 1477 | unsigned int cpu = (long)hcpu; |
| 1478 | struct cpu_hw_events *cpuc = &per_cpu(cpu_hw_events, cpu); |
| 1479 | int i, ret = NOTIFY_OK; |
| 1480 | |
| 1481 | switch (action & ~CPU_TASKS_FROZEN) { |
| 1482 | case CPU_UP_PREPARE: |
| 1483 | for (i = 0 ; i < X86_PERF_KFREE_MAX; i++) |
| 1484 | cpuc->kfree_on_online[i] = NULL; |
| 1485 | if (x86_pmu.cpu_prepare) |
| 1486 | ret = x86_pmu.cpu_prepare(cpu); |
| 1487 | break; |
| 1488 | |
| 1489 | case CPU_STARTING: |
| 1490 | if (x86_pmu.cpu_starting) |
| 1491 | x86_pmu.cpu_starting(cpu); |
| 1492 | break; |
| 1493 | |
| 1494 | case CPU_ONLINE: |
| 1495 | for (i = 0 ; i < X86_PERF_KFREE_MAX; i++) { |
| 1496 | kfree(cpuc->kfree_on_online[i]); |
| 1497 | cpuc->kfree_on_online[i] = NULL; |
| 1498 | } |
| 1499 | break; |
| 1500 | |
| 1501 | case CPU_DYING: |
| 1502 | if (x86_pmu.cpu_dying) |
| 1503 | x86_pmu.cpu_dying(cpu); |
| 1504 | break; |
| 1505 | |
| 1506 | case CPU_UP_CANCELED: |
| 1507 | case CPU_DEAD: |
| 1508 | if (x86_pmu.cpu_dead) |
| 1509 | x86_pmu.cpu_dead(cpu); |
| 1510 | break; |
| 1511 | |
| 1512 | default: |
| 1513 | break; |
| 1514 | } |
| 1515 | |
| 1516 | return ret; |
| 1517 | } |
| 1518 | |
| 1519 | static void __init pmu_check_apic(void) |
| 1520 | { |
| 1521 | if (cpu_has_apic) |
| 1522 | return; |
| 1523 | |
| 1524 | x86_pmu.apic = 0; |
| 1525 | pr_info("no APIC, boot with the \"lapic\" boot parameter to force-enable it.\n"); |
| 1526 | pr_info("no hardware sampling interrupt available.\n"); |
| 1527 | |
| 1528 | /* |
| 1529 | * If we have a PMU initialized but no APIC |
| 1530 | * interrupts, we cannot sample hardware |
| 1531 | * events (user-space has to fall back and |
| 1532 | * sample via a hrtimer based software event): |
| 1533 | */ |
| 1534 | pmu.capabilities |= PERF_PMU_CAP_NO_INTERRUPT; |
| 1535 | |
| 1536 | } |
| 1537 | |
| 1538 | static struct attribute_group x86_pmu_format_group = { |
| 1539 | .name = "format", |
| 1540 | .attrs = NULL, |
| 1541 | }; |
| 1542 | |
| 1543 | /* |
| 1544 | * Remove all undefined events (x86_pmu.event_map(id) == 0) |
| 1545 | * out of events_attr attributes. |
| 1546 | */ |
| 1547 | static void __init filter_events(struct attribute **attrs) |
| 1548 | { |
| 1549 | struct device_attribute *d; |
| 1550 | struct perf_pmu_events_attr *pmu_attr; |
| 1551 | int offset = 0; |
| 1552 | int i, j; |
| 1553 | |
| 1554 | for (i = 0; attrs[i]; i++) { |
| 1555 | d = (struct device_attribute *)attrs[i]; |
| 1556 | pmu_attr = container_of(d, struct perf_pmu_events_attr, attr); |
| 1557 | /* str trumps id */ |
| 1558 | if (pmu_attr->event_str) |
| 1559 | continue; |
| 1560 | if (x86_pmu.event_map(i + offset)) |
| 1561 | continue; |
| 1562 | |
| 1563 | for (j = i; attrs[j]; j++) |
| 1564 | attrs[j] = attrs[j + 1]; |
| 1565 | |
| 1566 | /* Check the shifted attr. */ |
| 1567 | i--; |
| 1568 | |
| 1569 | /* |
| 1570 | * event_map() is index based, the attrs array is organized |
| 1571 | * by increasing event index. If we shift the events, then |
| 1572 | * we need to compensate for the event_map(), otherwise |
| 1573 | * we are looking up the wrong event in the map |
| 1574 | */ |
| 1575 | offset++; |
| 1576 | } |
| 1577 | } |
| 1578 | |
| 1579 | /* Merge two pointer arrays */ |
| 1580 | __init struct attribute **merge_attr(struct attribute **a, struct attribute **b) |
| 1581 | { |
| 1582 | struct attribute **new; |
| 1583 | int j, i; |
| 1584 | |
| 1585 | for (j = 0; a[j]; j++) |
| 1586 | ; |
| 1587 | for (i = 0; b[i]; i++) |
| 1588 | j++; |
| 1589 | j++; |
| 1590 | |
| 1591 | new = kmalloc(sizeof(struct attribute *) * j, GFP_KERNEL); |
| 1592 | if (!new) |
| 1593 | return NULL; |
| 1594 | |
| 1595 | j = 0; |
| 1596 | for (i = 0; a[i]; i++) |
| 1597 | new[j++] = a[i]; |
| 1598 | for (i = 0; b[i]; i++) |
| 1599 | new[j++] = b[i]; |
| 1600 | new[j] = NULL; |
| 1601 | |
| 1602 | return new; |
| 1603 | } |
| 1604 | |
| 1605 | ssize_t events_sysfs_show(struct device *dev, struct device_attribute *attr, |
| 1606 | char *page) |
| 1607 | { |
| 1608 | struct perf_pmu_events_attr *pmu_attr = \ |
| 1609 | container_of(attr, struct perf_pmu_events_attr, attr); |
| 1610 | u64 config = x86_pmu.event_map(pmu_attr->id); |
| 1611 | |
| 1612 | /* string trumps id */ |
| 1613 | if (pmu_attr->event_str) |
| 1614 | return sprintf(page, "%s", pmu_attr->event_str); |
| 1615 | |
| 1616 | return x86_pmu.events_sysfs_show(page, config); |
| 1617 | } |
| 1618 | |
| 1619 | EVENT_ATTR(cpu-cycles, CPU_CYCLES ); |
| 1620 | EVENT_ATTR(instructions, INSTRUCTIONS ); |
| 1621 | EVENT_ATTR(cache-references, CACHE_REFERENCES ); |
| 1622 | EVENT_ATTR(cache-misses, CACHE_MISSES ); |
| 1623 | EVENT_ATTR(branch-instructions, BRANCH_INSTRUCTIONS ); |
| 1624 | EVENT_ATTR(branch-misses, BRANCH_MISSES ); |
| 1625 | EVENT_ATTR(bus-cycles, BUS_CYCLES ); |
| 1626 | EVENT_ATTR(stalled-cycles-frontend, STALLED_CYCLES_FRONTEND ); |
| 1627 | EVENT_ATTR(stalled-cycles-backend, STALLED_CYCLES_BACKEND ); |
| 1628 | EVENT_ATTR(ref-cycles, REF_CPU_CYCLES ); |
| 1629 | |
| 1630 | static struct attribute *empty_attrs; |
| 1631 | |
| 1632 | static struct attribute *events_attr[] = { |
| 1633 | EVENT_PTR(CPU_CYCLES), |
| 1634 | EVENT_PTR(INSTRUCTIONS), |
| 1635 | EVENT_PTR(CACHE_REFERENCES), |
| 1636 | EVENT_PTR(CACHE_MISSES), |
| 1637 | EVENT_PTR(BRANCH_INSTRUCTIONS), |
| 1638 | EVENT_PTR(BRANCH_MISSES), |
| 1639 | EVENT_PTR(BUS_CYCLES), |
| 1640 | EVENT_PTR(STALLED_CYCLES_FRONTEND), |
| 1641 | EVENT_PTR(STALLED_CYCLES_BACKEND), |
| 1642 | EVENT_PTR(REF_CPU_CYCLES), |
| 1643 | NULL, |
| 1644 | }; |
| 1645 | |
| 1646 | static struct attribute_group x86_pmu_events_group = { |
| 1647 | .name = "events", |
| 1648 | .attrs = events_attr, |
| 1649 | }; |
| 1650 | |
| 1651 | ssize_t x86_event_sysfs_show(char *page, u64 config, u64 event) |
| 1652 | { |
| 1653 | u64 umask = (config & ARCH_PERFMON_EVENTSEL_UMASK) >> 8; |
| 1654 | u64 cmask = (config & ARCH_PERFMON_EVENTSEL_CMASK) >> 24; |
| 1655 | bool edge = (config & ARCH_PERFMON_EVENTSEL_EDGE); |
| 1656 | bool pc = (config & ARCH_PERFMON_EVENTSEL_PIN_CONTROL); |
| 1657 | bool any = (config & ARCH_PERFMON_EVENTSEL_ANY); |
| 1658 | bool inv = (config & ARCH_PERFMON_EVENTSEL_INV); |
| 1659 | ssize_t ret; |
| 1660 | |
| 1661 | /* |
| 1662 | * We have whole page size to spend and just little data |
| 1663 | * to write, so we can safely use sprintf. |
| 1664 | */ |
| 1665 | ret = sprintf(page, "event=0x%02llx", event); |
| 1666 | |
| 1667 | if (umask) |
| 1668 | ret += sprintf(page + ret, ",umask=0x%02llx", umask); |
| 1669 | |
| 1670 | if (edge) |
| 1671 | ret += sprintf(page + ret, ",edge"); |
| 1672 | |
| 1673 | if (pc) |
| 1674 | ret += sprintf(page + ret, ",pc"); |
| 1675 | |
| 1676 | if (any) |
| 1677 | ret += sprintf(page + ret, ",any"); |
| 1678 | |
| 1679 | if (inv) |
| 1680 | ret += sprintf(page + ret, ",inv"); |
| 1681 | |
| 1682 | if (cmask) |
| 1683 | ret += sprintf(page + ret, ",cmask=0x%02llx", cmask); |
| 1684 | |
| 1685 | ret += sprintf(page + ret, "\n"); |
| 1686 | |
| 1687 | return ret; |
| 1688 | } |
| 1689 | |
| 1690 | static int __init init_hw_perf_events(void) |
| 1691 | { |
| 1692 | struct x86_pmu_quirk *quirk; |
| 1693 | int err; |
| 1694 | |
| 1695 | pr_info("Performance Events: "); |
| 1696 | |
| 1697 | switch (boot_cpu_data.x86_vendor) { |
| 1698 | case X86_VENDOR_INTEL: |
| 1699 | err = intel_pmu_init(); |
| 1700 | break; |
| 1701 | case X86_VENDOR_AMD: |
| 1702 | err = amd_pmu_init(); |
| 1703 | break; |
| 1704 | default: |
| 1705 | err = -ENOTSUPP; |
| 1706 | } |
| 1707 | if (err != 0) { |
| 1708 | pr_cont("no PMU driver, software events only.\n"); |
| 1709 | return 0; |
| 1710 | } |
| 1711 | |
| 1712 | pmu_check_apic(); |
| 1713 | |
| 1714 | /* sanity check that the hardware exists or is emulated */ |
| 1715 | if (!check_hw_exists()) |
| 1716 | return 0; |
| 1717 | |
| 1718 | pr_cont("%s PMU driver.\n", x86_pmu.name); |
| 1719 | |
| 1720 | x86_pmu.attr_rdpmc = 1; /* enable userspace RDPMC usage by default */ |
| 1721 | |
| 1722 | for (quirk = x86_pmu.quirks; quirk; quirk = quirk->next) |
| 1723 | quirk->func(); |
| 1724 | |
| 1725 | if (!x86_pmu.intel_ctrl) |
| 1726 | x86_pmu.intel_ctrl = (1 << x86_pmu.num_counters) - 1; |
| 1727 | |
| 1728 | perf_events_lapic_init(); |
| 1729 | register_nmi_handler(NMI_LOCAL, perf_event_nmi_handler, 0, "PMI"); |
| 1730 | |
| 1731 | unconstrained = (struct event_constraint) |
| 1732 | __EVENT_CONSTRAINT(0, (1ULL << x86_pmu.num_counters) - 1, |
| 1733 | 0, x86_pmu.num_counters, 0, 0); |
| 1734 | |
| 1735 | x86_pmu_format_group.attrs = x86_pmu.format_attrs; |
| 1736 | |
| 1737 | if (x86_pmu.event_attrs) |
| 1738 | x86_pmu_events_group.attrs = x86_pmu.event_attrs; |
| 1739 | |
| 1740 | if (!x86_pmu.events_sysfs_show) |
| 1741 | x86_pmu_events_group.attrs = &empty_attrs; |
| 1742 | else |
| 1743 | filter_events(x86_pmu_events_group.attrs); |
| 1744 | |
| 1745 | if (x86_pmu.cpu_events) { |
| 1746 | struct attribute **tmp; |
| 1747 | |
| 1748 | tmp = merge_attr(x86_pmu_events_group.attrs, x86_pmu.cpu_events); |
| 1749 | if (!WARN_ON(!tmp)) |
| 1750 | x86_pmu_events_group.attrs = tmp; |
| 1751 | } |
| 1752 | |
| 1753 | pr_info("... version: %d\n", x86_pmu.version); |
| 1754 | pr_info("... bit width: %d\n", x86_pmu.cntval_bits); |
| 1755 | pr_info("... generic registers: %d\n", x86_pmu.num_counters); |
| 1756 | pr_info("... value mask: %016Lx\n", x86_pmu.cntval_mask); |
| 1757 | pr_info("... max period: %016Lx\n", x86_pmu.max_period); |
| 1758 | pr_info("... fixed-purpose events: %d\n", x86_pmu.num_counters_fixed); |
| 1759 | pr_info("... event mask: %016Lx\n", x86_pmu.intel_ctrl); |
| 1760 | |
| 1761 | perf_pmu_register(&pmu, "cpu", PERF_TYPE_RAW); |
| 1762 | perf_cpu_notifier(x86_pmu_notifier); |
| 1763 | |
| 1764 | return 0; |
| 1765 | } |
| 1766 | early_initcall(init_hw_perf_events); |
| 1767 | |
| 1768 | static inline void x86_pmu_read(struct perf_event *event) |
| 1769 | { |
| 1770 | x86_perf_event_update(event); |
| 1771 | } |
| 1772 | |
| 1773 | /* |
| 1774 | * Start group events scheduling transaction |
| 1775 | * Set the flag to make pmu::enable() not perform the |
| 1776 | * schedulability test, it will be performed at commit time |
| 1777 | * |
| 1778 | * We only support PERF_PMU_TXN_ADD transactions. Save the |
| 1779 | * transaction flags but otherwise ignore non-PERF_PMU_TXN_ADD |
| 1780 | * transactions. |
| 1781 | */ |
| 1782 | static void x86_pmu_start_txn(struct pmu *pmu, unsigned int txn_flags) |
| 1783 | { |
| 1784 | struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); |
| 1785 | |
| 1786 | WARN_ON_ONCE(cpuc->txn_flags); /* txn already in flight */ |
| 1787 | |
| 1788 | cpuc->txn_flags = txn_flags; |
| 1789 | if (txn_flags & ~PERF_PMU_TXN_ADD) |
| 1790 | return; |
| 1791 | |
| 1792 | perf_pmu_disable(pmu); |
| 1793 | __this_cpu_write(cpu_hw_events.n_txn, 0); |
| 1794 | } |
| 1795 | |
| 1796 | /* |
| 1797 | * Stop group events scheduling transaction |
| 1798 | * Clear the flag and pmu::enable() will perform the |
| 1799 | * schedulability test. |
| 1800 | */ |
| 1801 | static void x86_pmu_cancel_txn(struct pmu *pmu) |
| 1802 | { |
| 1803 | unsigned int txn_flags; |
| 1804 | struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); |
| 1805 | |
| 1806 | WARN_ON_ONCE(!cpuc->txn_flags); /* no txn in flight */ |
| 1807 | |
| 1808 | txn_flags = cpuc->txn_flags; |
| 1809 | cpuc->txn_flags = 0; |
| 1810 | if (txn_flags & ~PERF_PMU_TXN_ADD) |
| 1811 | return; |
| 1812 | |
| 1813 | /* |
| 1814 | * Truncate collected array by the number of events added in this |
| 1815 | * transaction. See x86_pmu_add() and x86_pmu_*_txn(). |
| 1816 | */ |
| 1817 | __this_cpu_sub(cpu_hw_events.n_added, __this_cpu_read(cpu_hw_events.n_txn)); |
| 1818 | __this_cpu_sub(cpu_hw_events.n_events, __this_cpu_read(cpu_hw_events.n_txn)); |
| 1819 | perf_pmu_enable(pmu); |
| 1820 | } |
| 1821 | |
| 1822 | /* |
| 1823 | * Commit group events scheduling transaction |
| 1824 | * Perform the group schedulability test as a whole |
| 1825 | * Return 0 if success |
| 1826 | * |
| 1827 | * Does not cancel the transaction on failure; expects the caller to do this. |
| 1828 | */ |
| 1829 | static int x86_pmu_commit_txn(struct pmu *pmu) |
| 1830 | { |
| 1831 | struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); |
| 1832 | int assign[X86_PMC_IDX_MAX]; |
| 1833 | int n, ret; |
| 1834 | |
| 1835 | WARN_ON_ONCE(!cpuc->txn_flags); /* no txn in flight */ |
| 1836 | |
| 1837 | if (cpuc->txn_flags & ~PERF_PMU_TXN_ADD) { |
| 1838 | cpuc->txn_flags = 0; |
| 1839 | return 0; |
| 1840 | } |
| 1841 | |
| 1842 | n = cpuc->n_events; |
| 1843 | |
| 1844 | if (!x86_pmu_initialized()) |
| 1845 | return -EAGAIN; |
| 1846 | |
| 1847 | ret = x86_pmu.schedule_events(cpuc, n, assign); |
| 1848 | if (ret) |
| 1849 | return ret; |
| 1850 | |
| 1851 | /* |
| 1852 | * copy new assignment, now we know it is possible |
| 1853 | * will be used by hw_perf_enable() |
| 1854 | */ |
| 1855 | memcpy(cpuc->assign, assign, n*sizeof(int)); |
| 1856 | |
| 1857 | cpuc->txn_flags = 0; |
| 1858 | perf_pmu_enable(pmu); |
| 1859 | return 0; |
| 1860 | } |
| 1861 | /* |
| 1862 | * a fake_cpuc is used to validate event groups. Due to |
| 1863 | * the extra reg logic, we need to also allocate a fake |
| 1864 | * per_core and per_cpu structure. Otherwise, group events |
| 1865 | * using extra reg may conflict without the kernel being |
| 1866 | * able to catch this when the last event gets added to |
| 1867 | * the group. |
| 1868 | */ |
| 1869 | static void free_fake_cpuc(struct cpu_hw_events *cpuc) |
| 1870 | { |
| 1871 | kfree(cpuc->shared_regs); |
| 1872 | kfree(cpuc); |
| 1873 | } |
| 1874 | |
| 1875 | static struct cpu_hw_events *allocate_fake_cpuc(void) |
| 1876 | { |
| 1877 | struct cpu_hw_events *cpuc; |
| 1878 | int cpu = raw_smp_processor_id(); |
| 1879 | |
| 1880 | cpuc = kzalloc(sizeof(*cpuc), GFP_KERNEL); |
| 1881 | if (!cpuc) |
| 1882 | return ERR_PTR(-ENOMEM); |
| 1883 | |
| 1884 | /* only needed, if we have extra_regs */ |
| 1885 | if (x86_pmu.extra_regs) { |
| 1886 | cpuc->shared_regs = allocate_shared_regs(cpu); |
| 1887 | if (!cpuc->shared_regs) |
| 1888 | goto error; |
| 1889 | } |
| 1890 | cpuc->is_fake = 1; |
| 1891 | return cpuc; |
| 1892 | error: |
| 1893 | free_fake_cpuc(cpuc); |
| 1894 | return ERR_PTR(-ENOMEM); |
| 1895 | } |
| 1896 | |
| 1897 | /* |
| 1898 | * validate that we can schedule this event |
| 1899 | */ |
| 1900 | static int validate_event(struct perf_event *event) |
| 1901 | { |
| 1902 | struct cpu_hw_events *fake_cpuc; |
| 1903 | struct event_constraint *c; |
| 1904 | int ret = 0; |
| 1905 | |
| 1906 | fake_cpuc = allocate_fake_cpuc(); |
| 1907 | if (IS_ERR(fake_cpuc)) |
| 1908 | return PTR_ERR(fake_cpuc); |
| 1909 | |
| 1910 | c = x86_pmu.get_event_constraints(fake_cpuc, -1, event); |
| 1911 | |
| 1912 | if (!c || !c->weight) |
| 1913 | ret = -EINVAL; |
| 1914 | |
| 1915 | if (x86_pmu.put_event_constraints) |
| 1916 | x86_pmu.put_event_constraints(fake_cpuc, event); |
| 1917 | |
| 1918 | free_fake_cpuc(fake_cpuc); |
| 1919 | |
| 1920 | return ret; |
| 1921 | } |
| 1922 | |
| 1923 | /* |
| 1924 | * validate a single event group |
| 1925 | * |
| 1926 | * validation include: |
| 1927 | * - check events are compatible which each other |
| 1928 | * - events do not compete for the same counter |
| 1929 | * - number of events <= number of counters |
| 1930 | * |
| 1931 | * validation ensures the group can be loaded onto the |
| 1932 | * PMU if it was the only group available. |
| 1933 | */ |
| 1934 | static int validate_group(struct perf_event *event) |
| 1935 | { |
| 1936 | struct perf_event *leader = event->group_leader; |
| 1937 | struct cpu_hw_events *fake_cpuc; |
| 1938 | int ret = -EINVAL, n; |
| 1939 | |
| 1940 | fake_cpuc = allocate_fake_cpuc(); |
| 1941 | if (IS_ERR(fake_cpuc)) |
| 1942 | return PTR_ERR(fake_cpuc); |
| 1943 | /* |
| 1944 | * the event is not yet connected with its |
| 1945 | * siblings therefore we must first collect |
| 1946 | * existing siblings, then add the new event |
| 1947 | * before we can simulate the scheduling |
| 1948 | */ |
| 1949 | n = collect_events(fake_cpuc, leader, true); |
| 1950 | if (n < 0) |
| 1951 | goto out; |
| 1952 | |
| 1953 | fake_cpuc->n_events = n; |
| 1954 | n = collect_events(fake_cpuc, event, false); |
| 1955 | if (n < 0) |
| 1956 | goto out; |
| 1957 | |
| 1958 | fake_cpuc->n_events = n; |
| 1959 | |
| 1960 | ret = x86_pmu.schedule_events(fake_cpuc, n, NULL); |
| 1961 | |
| 1962 | out: |
| 1963 | free_fake_cpuc(fake_cpuc); |
| 1964 | return ret; |
| 1965 | } |
| 1966 | |
| 1967 | static int x86_pmu_event_init(struct perf_event *event) |
| 1968 | { |
| 1969 | struct pmu *tmp; |
| 1970 | int err; |
| 1971 | |
| 1972 | switch (event->attr.type) { |
| 1973 | case PERF_TYPE_RAW: |
| 1974 | case PERF_TYPE_HARDWARE: |
| 1975 | case PERF_TYPE_HW_CACHE: |
| 1976 | break; |
| 1977 | |
| 1978 | default: |
| 1979 | return -ENOENT; |
| 1980 | } |
| 1981 | |
| 1982 | err = __x86_pmu_event_init(event); |
| 1983 | if (!err) { |
| 1984 | /* |
| 1985 | * we temporarily connect event to its pmu |
| 1986 | * such that validate_group() can classify |
| 1987 | * it as an x86 event using is_x86_event() |
| 1988 | */ |
| 1989 | tmp = event->pmu; |
| 1990 | event->pmu = &pmu; |
| 1991 | |
| 1992 | if (event->group_leader != event) |
| 1993 | err = validate_group(event); |
| 1994 | else |
| 1995 | err = validate_event(event); |
| 1996 | |
| 1997 | event->pmu = tmp; |
| 1998 | } |
| 1999 | if (err) { |
| 2000 | if (event->destroy) |
| 2001 | event->destroy(event); |
| 2002 | } |
| 2003 | |
| 2004 | if (ACCESS_ONCE(x86_pmu.attr_rdpmc)) |
| 2005 | event->hw.flags |= PERF_X86_EVENT_RDPMC_ALLOWED; |
| 2006 | |
| 2007 | return err; |
| 2008 | } |
| 2009 | |
| 2010 | static void refresh_pce(void *ignored) |
| 2011 | { |
| 2012 | if (current->mm) |
| 2013 | load_mm_cr4(current->mm); |
| 2014 | } |
| 2015 | |
| 2016 | static void x86_pmu_event_mapped(struct perf_event *event) |
| 2017 | { |
| 2018 | if (!(event->hw.flags & PERF_X86_EVENT_RDPMC_ALLOWED)) |
| 2019 | return; |
| 2020 | |
| 2021 | if (atomic_inc_return(¤t->mm->context.perf_rdpmc_allowed) == 1) |
| 2022 | on_each_cpu_mask(mm_cpumask(current->mm), refresh_pce, NULL, 1); |
| 2023 | } |
| 2024 | |
| 2025 | static void x86_pmu_event_unmapped(struct perf_event *event) |
| 2026 | { |
| 2027 | if (!current->mm) |
| 2028 | return; |
| 2029 | |
| 2030 | if (!(event->hw.flags & PERF_X86_EVENT_RDPMC_ALLOWED)) |
| 2031 | return; |
| 2032 | |
| 2033 | if (atomic_dec_and_test(¤t->mm->context.perf_rdpmc_allowed)) |
| 2034 | on_each_cpu_mask(mm_cpumask(current->mm), refresh_pce, NULL, 1); |
| 2035 | } |
| 2036 | |
| 2037 | static int x86_pmu_event_idx(struct perf_event *event) |
| 2038 | { |
| 2039 | int idx = event->hw.idx; |
| 2040 | |
| 2041 | if (!(event->hw.flags & PERF_X86_EVENT_RDPMC_ALLOWED)) |
| 2042 | return 0; |
| 2043 | |
| 2044 | if (x86_pmu.num_counters_fixed && idx >= INTEL_PMC_IDX_FIXED) { |
| 2045 | idx -= INTEL_PMC_IDX_FIXED; |
| 2046 | idx |= 1 << 30; |
| 2047 | } |
| 2048 | |
| 2049 | return idx + 1; |
| 2050 | } |
| 2051 | |
| 2052 | static ssize_t get_attr_rdpmc(struct device *cdev, |
| 2053 | struct device_attribute *attr, |
| 2054 | char *buf) |
| 2055 | { |
| 2056 | return snprintf(buf, 40, "%d\n", x86_pmu.attr_rdpmc); |
| 2057 | } |
| 2058 | |
| 2059 | static ssize_t set_attr_rdpmc(struct device *cdev, |
| 2060 | struct device_attribute *attr, |
| 2061 | const char *buf, size_t count) |
| 2062 | { |
| 2063 | unsigned long val; |
| 2064 | ssize_t ret; |
| 2065 | |
| 2066 | ret = kstrtoul(buf, 0, &val); |
| 2067 | if (ret) |
| 2068 | return ret; |
| 2069 | |
| 2070 | if (val > 2) |
| 2071 | return -EINVAL; |
| 2072 | |
| 2073 | if (x86_pmu.attr_rdpmc_broken) |
| 2074 | return -ENOTSUPP; |
| 2075 | |
| 2076 | if ((val == 2) != (x86_pmu.attr_rdpmc == 2)) { |
| 2077 | /* |
| 2078 | * Changing into or out of always available, aka |
| 2079 | * perf-event-bypassing mode. This path is extremely slow, |
| 2080 | * but only root can trigger it, so it's okay. |
| 2081 | */ |
| 2082 | if (val == 2) |
| 2083 | static_key_slow_inc(&rdpmc_always_available); |
| 2084 | else |
| 2085 | static_key_slow_dec(&rdpmc_always_available); |
| 2086 | on_each_cpu(refresh_pce, NULL, 1); |
| 2087 | } |
| 2088 | |
| 2089 | x86_pmu.attr_rdpmc = val; |
| 2090 | |
| 2091 | return count; |
| 2092 | } |
| 2093 | |
| 2094 | static DEVICE_ATTR(rdpmc, S_IRUSR | S_IWUSR, get_attr_rdpmc, set_attr_rdpmc); |
| 2095 | |
| 2096 | static struct attribute *x86_pmu_attrs[] = { |
| 2097 | &dev_attr_rdpmc.attr, |
| 2098 | NULL, |
| 2099 | }; |
| 2100 | |
| 2101 | static struct attribute_group x86_pmu_attr_group = { |
| 2102 | .attrs = x86_pmu_attrs, |
| 2103 | }; |
| 2104 | |
| 2105 | static const struct attribute_group *x86_pmu_attr_groups[] = { |
| 2106 | &x86_pmu_attr_group, |
| 2107 | &x86_pmu_format_group, |
| 2108 | &x86_pmu_events_group, |
| 2109 | NULL, |
| 2110 | }; |
| 2111 | |
| 2112 | static void x86_pmu_sched_task(struct perf_event_context *ctx, bool sched_in) |
| 2113 | { |
| 2114 | if (x86_pmu.sched_task) |
| 2115 | x86_pmu.sched_task(ctx, sched_in); |
| 2116 | } |
| 2117 | |
| 2118 | void perf_check_microcode(void) |
| 2119 | { |
| 2120 | if (x86_pmu.check_microcode) |
| 2121 | x86_pmu.check_microcode(); |
| 2122 | } |
| 2123 | EXPORT_SYMBOL_GPL(perf_check_microcode); |
| 2124 | |
| 2125 | static struct pmu pmu = { |
| 2126 | .pmu_enable = x86_pmu_enable, |
| 2127 | .pmu_disable = x86_pmu_disable, |
| 2128 | |
| 2129 | .attr_groups = x86_pmu_attr_groups, |
| 2130 | |
| 2131 | .event_init = x86_pmu_event_init, |
| 2132 | |
| 2133 | .event_mapped = x86_pmu_event_mapped, |
| 2134 | .event_unmapped = x86_pmu_event_unmapped, |
| 2135 | |
| 2136 | .add = x86_pmu_add, |
| 2137 | .del = x86_pmu_del, |
| 2138 | .start = x86_pmu_start, |
| 2139 | .stop = x86_pmu_stop, |
| 2140 | .read = x86_pmu_read, |
| 2141 | |
| 2142 | .start_txn = x86_pmu_start_txn, |
| 2143 | .cancel_txn = x86_pmu_cancel_txn, |
| 2144 | .commit_txn = x86_pmu_commit_txn, |
| 2145 | |
| 2146 | .event_idx = x86_pmu_event_idx, |
| 2147 | .sched_task = x86_pmu_sched_task, |
| 2148 | .task_ctx_size = sizeof(struct x86_perf_task_context), |
| 2149 | }; |
| 2150 | |
| 2151 | void arch_perf_update_userpage(struct perf_event *event, |
| 2152 | struct perf_event_mmap_page *userpg, u64 now) |
| 2153 | { |
| 2154 | struct cyc2ns_data *data; |
| 2155 | |
| 2156 | userpg->cap_user_time = 0; |
| 2157 | userpg->cap_user_time_zero = 0; |
| 2158 | userpg->cap_user_rdpmc = |
| 2159 | !!(event->hw.flags & PERF_X86_EVENT_RDPMC_ALLOWED); |
| 2160 | userpg->pmc_width = x86_pmu.cntval_bits; |
| 2161 | |
| 2162 | if (!sched_clock_stable()) |
| 2163 | return; |
| 2164 | |
| 2165 | data = cyc2ns_read_begin(); |
| 2166 | |
| 2167 | /* |
| 2168 | * Internal timekeeping for enabled/running/stopped times |
| 2169 | * is always in the local_clock domain. |
| 2170 | */ |
| 2171 | userpg->cap_user_time = 1; |
| 2172 | userpg->time_mult = data->cyc2ns_mul; |
| 2173 | userpg->time_shift = data->cyc2ns_shift; |
| 2174 | userpg->time_offset = data->cyc2ns_offset - now; |
| 2175 | |
| 2176 | /* |
| 2177 | * cap_user_time_zero doesn't make sense when we're using a different |
| 2178 | * time base for the records. |
| 2179 | */ |
| 2180 | if (event->clock == &local_clock) { |
| 2181 | userpg->cap_user_time_zero = 1; |
| 2182 | userpg->time_zero = data->cyc2ns_offset; |
| 2183 | } |
| 2184 | |
| 2185 | cyc2ns_read_end(data); |
| 2186 | } |
| 2187 | |
| 2188 | /* |
| 2189 | * callchain support |
| 2190 | */ |
| 2191 | |
| 2192 | static int backtrace_stack(void *data, char *name) |
| 2193 | { |
| 2194 | return 0; |
| 2195 | } |
| 2196 | |
| 2197 | static void backtrace_address(void *data, unsigned long addr, int reliable) |
| 2198 | { |
| 2199 | struct perf_callchain_entry *entry = data; |
| 2200 | |
| 2201 | perf_callchain_store(entry, addr); |
| 2202 | } |
| 2203 | |
| 2204 | static const struct stacktrace_ops backtrace_ops = { |
| 2205 | .stack = backtrace_stack, |
| 2206 | .address = backtrace_address, |
| 2207 | .walk_stack = print_context_stack_bp, |
| 2208 | }; |
| 2209 | |
| 2210 | void |
| 2211 | perf_callchain_kernel(struct perf_callchain_entry *entry, struct pt_regs *regs) |
| 2212 | { |
| 2213 | if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) { |
| 2214 | /* TODO: We don't support guest os callchain now */ |
| 2215 | return; |
| 2216 | } |
| 2217 | |
| 2218 | perf_callchain_store(entry, regs->ip); |
| 2219 | |
| 2220 | dump_trace(NULL, regs, NULL, 0, &backtrace_ops, entry); |
| 2221 | } |
| 2222 | |
| 2223 | static inline int |
| 2224 | valid_user_frame(const void __user *fp, unsigned long size) |
| 2225 | { |
| 2226 | return (__range_not_ok(fp, size, TASK_SIZE) == 0); |
| 2227 | } |
| 2228 | |
| 2229 | static unsigned long get_segment_base(unsigned int segment) |
| 2230 | { |
| 2231 | struct desc_struct *desc; |
| 2232 | int idx = segment >> 3; |
| 2233 | |
| 2234 | if ((segment & SEGMENT_TI_MASK) == SEGMENT_LDT) { |
| 2235 | #ifdef CONFIG_MODIFY_LDT_SYSCALL |
| 2236 | struct ldt_struct *ldt; |
| 2237 | |
| 2238 | if (idx > LDT_ENTRIES) |
| 2239 | return 0; |
| 2240 | |
| 2241 | /* IRQs are off, so this synchronizes with smp_store_release */ |
| 2242 | ldt = lockless_dereference(current->active_mm->context.ldt); |
| 2243 | if (!ldt || idx > ldt->size) |
| 2244 | return 0; |
| 2245 | |
| 2246 | desc = &ldt->entries[idx]; |
| 2247 | #else |
| 2248 | return 0; |
| 2249 | #endif |
| 2250 | } else { |
| 2251 | if (idx > GDT_ENTRIES) |
| 2252 | return 0; |
| 2253 | |
| 2254 | desc = raw_cpu_ptr(gdt_page.gdt) + idx; |
| 2255 | } |
| 2256 | |
| 2257 | return get_desc_base(desc); |
| 2258 | } |
| 2259 | |
| 2260 | #ifdef CONFIG_IA32_EMULATION |
| 2261 | |
| 2262 | #include <asm/compat.h> |
| 2263 | |
| 2264 | static inline int |
| 2265 | perf_callchain_user32(struct pt_regs *regs, struct perf_callchain_entry *entry) |
| 2266 | { |
| 2267 | /* 32-bit process in 64-bit kernel. */ |
| 2268 | unsigned long ss_base, cs_base; |
| 2269 | struct stack_frame_ia32 frame; |
| 2270 | const void __user *fp; |
| 2271 | |
| 2272 | if (!test_thread_flag(TIF_IA32)) |
| 2273 | return 0; |
| 2274 | |
| 2275 | cs_base = get_segment_base(regs->cs); |
| 2276 | ss_base = get_segment_base(regs->ss); |
| 2277 | |
| 2278 | fp = compat_ptr(ss_base + regs->bp); |
| 2279 | pagefault_disable(); |
| 2280 | while (entry->nr < PERF_MAX_STACK_DEPTH) { |
| 2281 | unsigned long bytes; |
| 2282 | frame.next_frame = 0; |
| 2283 | frame.return_address = 0; |
| 2284 | |
| 2285 | if (!access_ok(VERIFY_READ, fp, 8)) |
| 2286 | break; |
| 2287 | |
| 2288 | bytes = __copy_from_user_nmi(&frame.next_frame, fp, 4); |
| 2289 | if (bytes != 0) |
| 2290 | break; |
| 2291 | bytes = __copy_from_user_nmi(&frame.return_address, fp+4, 4); |
| 2292 | if (bytes != 0) |
| 2293 | break; |
| 2294 | |
| 2295 | if (!valid_user_frame(fp, sizeof(frame))) |
| 2296 | break; |
| 2297 | |
| 2298 | perf_callchain_store(entry, cs_base + frame.return_address); |
| 2299 | fp = compat_ptr(ss_base + frame.next_frame); |
| 2300 | } |
| 2301 | pagefault_enable(); |
| 2302 | return 1; |
| 2303 | } |
| 2304 | #else |
| 2305 | static inline int |
| 2306 | perf_callchain_user32(struct pt_regs *regs, struct perf_callchain_entry *entry) |
| 2307 | { |
| 2308 | return 0; |
| 2309 | } |
| 2310 | #endif |
| 2311 | |
| 2312 | void |
| 2313 | perf_callchain_user(struct perf_callchain_entry *entry, struct pt_regs *regs) |
| 2314 | { |
| 2315 | struct stack_frame frame; |
| 2316 | const void __user *fp; |
| 2317 | |
| 2318 | if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) { |
| 2319 | /* TODO: We don't support guest os callchain now */ |
| 2320 | return; |
| 2321 | } |
| 2322 | |
| 2323 | /* |
| 2324 | * We don't know what to do with VM86 stacks.. ignore them for now. |
| 2325 | */ |
| 2326 | if (regs->flags & (X86_VM_MASK | PERF_EFLAGS_VM)) |
| 2327 | return; |
| 2328 | |
| 2329 | fp = (void __user *)regs->bp; |
| 2330 | |
| 2331 | perf_callchain_store(entry, regs->ip); |
| 2332 | |
| 2333 | if (!current->mm) |
| 2334 | return; |
| 2335 | |
| 2336 | if (perf_callchain_user32(regs, entry)) |
| 2337 | return; |
| 2338 | |
| 2339 | pagefault_disable(); |
| 2340 | while (entry->nr < PERF_MAX_STACK_DEPTH) { |
| 2341 | unsigned long bytes; |
| 2342 | frame.next_frame = NULL; |
| 2343 | frame.return_address = 0; |
| 2344 | |
| 2345 | if (!access_ok(VERIFY_READ, fp, 16)) |
| 2346 | break; |
| 2347 | |
| 2348 | bytes = __copy_from_user_nmi(&frame.next_frame, fp, 8); |
| 2349 | if (bytes != 0) |
| 2350 | break; |
| 2351 | bytes = __copy_from_user_nmi(&frame.return_address, fp+8, 8); |
| 2352 | if (bytes != 0) |
| 2353 | break; |
| 2354 | |
| 2355 | if (!valid_user_frame(fp, sizeof(frame))) |
| 2356 | break; |
| 2357 | |
| 2358 | perf_callchain_store(entry, frame.return_address); |
| 2359 | fp = (void __user *)frame.next_frame; |
| 2360 | } |
| 2361 | pagefault_enable(); |
| 2362 | } |
| 2363 | |
| 2364 | /* |
| 2365 | * Deal with code segment offsets for the various execution modes: |
| 2366 | * |
| 2367 | * VM86 - the good olde 16 bit days, where the linear address is |
| 2368 | * 20 bits and we use regs->ip + 0x10 * regs->cs. |
| 2369 | * |
| 2370 | * IA32 - Where we need to look at GDT/LDT segment descriptor tables |
| 2371 | * to figure out what the 32bit base address is. |
| 2372 | * |
| 2373 | * X32 - has TIF_X32 set, but is running in x86_64 |
| 2374 | * |
| 2375 | * X86_64 - CS,DS,SS,ES are all zero based. |
| 2376 | */ |
| 2377 | static unsigned long code_segment_base(struct pt_regs *regs) |
| 2378 | { |
| 2379 | /* |
| 2380 | * For IA32 we look at the GDT/LDT segment base to convert the |
| 2381 | * effective IP to a linear address. |
| 2382 | */ |
| 2383 | |
| 2384 | #ifdef CONFIG_X86_32 |
| 2385 | /* |
| 2386 | * If we are in VM86 mode, add the segment offset to convert to a |
| 2387 | * linear address. |
| 2388 | */ |
| 2389 | if (regs->flags & X86_VM_MASK) |
| 2390 | return 0x10 * regs->cs; |
| 2391 | |
| 2392 | if (user_mode(regs) && regs->cs != __USER_CS) |
| 2393 | return get_segment_base(regs->cs); |
| 2394 | #else |
| 2395 | if (user_mode(regs) && !user_64bit_mode(regs) && |
| 2396 | regs->cs != __USER32_CS) |
| 2397 | return get_segment_base(regs->cs); |
| 2398 | #endif |
| 2399 | return 0; |
| 2400 | } |
| 2401 | |
| 2402 | unsigned long perf_instruction_pointer(struct pt_regs *regs) |
| 2403 | { |
| 2404 | if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) |
| 2405 | return perf_guest_cbs->get_guest_ip(); |
| 2406 | |
| 2407 | return regs->ip + code_segment_base(regs); |
| 2408 | } |
| 2409 | |
| 2410 | unsigned long perf_misc_flags(struct pt_regs *regs) |
| 2411 | { |
| 2412 | int misc = 0; |
| 2413 | |
| 2414 | if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) { |
| 2415 | if (perf_guest_cbs->is_user_mode()) |
| 2416 | misc |= PERF_RECORD_MISC_GUEST_USER; |
| 2417 | else |
| 2418 | misc |= PERF_RECORD_MISC_GUEST_KERNEL; |
| 2419 | } else { |
| 2420 | if (user_mode(regs)) |
| 2421 | misc |= PERF_RECORD_MISC_USER; |
| 2422 | else |
| 2423 | misc |= PERF_RECORD_MISC_KERNEL; |
| 2424 | } |
| 2425 | |
| 2426 | if (regs->flags & PERF_EFLAGS_EXACT) |
| 2427 | misc |= PERF_RECORD_MISC_EXACT_IP; |
| 2428 | |
| 2429 | return misc; |
| 2430 | } |
| 2431 | |
| 2432 | void perf_get_x86_pmu_capability(struct x86_pmu_capability *cap) |
| 2433 | { |
| 2434 | cap->version = x86_pmu.version; |
| 2435 | cap->num_counters_gp = x86_pmu.num_counters; |
| 2436 | cap->num_counters_fixed = x86_pmu.num_counters_fixed; |
| 2437 | cap->bit_width_gp = x86_pmu.cntval_bits; |
| 2438 | cap->bit_width_fixed = x86_pmu.cntval_bits; |
| 2439 | cap->events_mask = (unsigned int)x86_pmu.events_maskl; |
| 2440 | cap->events_mask_len = x86_pmu.events_mask_len; |
| 2441 | } |
| 2442 | EXPORT_SYMBOL_GPL(perf_get_x86_pmu_capability); |