1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/perf_event.h> 3 #include <linux/types.h> 4 5 #include <asm/perf_event.h> 6 #include <asm/msr.h> 7 #include <asm/insn.h> 8 9 #include "../perf_event.h" 10 11 /* 12 * Intel LBR_SELECT bits 13 * Intel Vol3a, April 2011, Section 16.7 Table 16-10 14 * 15 * Hardware branch filter (not available on all CPUs) 16 */ 17 #define LBR_KERNEL_BIT 0 /* do not capture at ring0 */ 18 #define LBR_USER_BIT 1 /* do not capture at ring > 0 */ 19 #define LBR_JCC_BIT 2 /* do not capture conditional branches */ 20 #define LBR_REL_CALL_BIT 3 /* do not capture relative calls */ 21 #define LBR_IND_CALL_BIT 4 /* do not capture indirect calls */ 22 #define LBR_RETURN_BIT 5 /* do not capture near returns */ 23 #define LBR_IND_JMP_BIT 6 /* do not capture indirect jumps */ 24 #define LBR_REL_JMP_BIT 7 /* do not capture relative jumps */ 25 #define LBR_FAR_BIT 8 /* do not capture far branches */ 26 #define LBR_CALL_STACK_BIT 9 /* enable call stack */ 27 28 /* 29 * Following bit only exists in Linux; we mask it out before writing it to 30 * the actual MSR. But it helps the constraint perf code to understand 31 * that this is a separate configuration. 32 */ 33 #define LBR_NO_INFO_BIT 63 /* don't read LBR_INFO. */ 34 35 #define LBR_KERNEL (1 << LBR_KERNEL_BIT) 36 #define LBR_USER (1 << LBR_USER_BIT) 37 #define LBR_JCC (1 << LBR_JCC_BIT) 38 #define LBR_REL_CALL (1 << LBR_REL_CALL_BIT) 39 #define LBR_IND_CALL (1 << LBR_IND_CALL_BIT) 40 #define LBR_RETURN (1 << LBR_RETURN_BIT) 41 #define LBR_REL_JMP (1 << LBR_REL_JMP_BIT) 42 #define LBR_IND_JMP (1 << LBR_IND_JMP_BIT) 43 #define LBR_FAR (1 << LBR_FAR_BIT) 44 #define LBR_CALL_STACK (1 << LBR_CALL_STACK_BIT) 45 #define LBR_NO_INFO (1ULL << LBR_NO_INFO_BIT) 46 47 #define LBR_PLM (LBR_KERNEL | LBR_USER) 48 49 #define LBR_SEL_MASK 0x3ff /* valid bits in LBR_SELECT */ 50 #define LBR_NOT_SUPP -1 /* LBR filter not supported */ 51 #define LBR_IGN 0 /* ignored */ 52 53 #define LBR_ANY \ 54 (LBR_JCC |\ 55 LBR_REL_CALL |\ 56 LBR_IND_CALL |\ 57 LBR_RETURN |\ 58 LBR_REL_JMP |\ 59 LBR_IND_JMP |\ 60 LBR_FAR) 61 62 #define LBR_FROM_FLAG_MISPRED BIT_ULL(63) 63 #define LBR_FROM_FLAG_IN_TX BIT_ULL(62) 64 #define LBR_FROM_FLAG_ABORT BIT_ULL(61) 65 66 #define LBR_FROM_SIGNEXT_2MSB (BIT_ULL(60) | BIT_ULL(59)) 67 68 /* 69 * x86control flow change classification 70 * x86control flow changes include branches, interrupts, traps, faults 71 */ 72 enum { 73 X86_BR_NONE = 0, /* unknown */ 74 75 X86_BR_USER = 1 << 0, /* branch target is user */ 76 X86_BR_KERNEL = 1 << 1, /* branch target is kernel */ 77 78 X86_BR_CALL = 1 << 2, /* call */ 79 X86_BR_RET = 1 << 3, /* return */ 80 X86_BR_SYSCALL = 1 << 4, /* syscall */ 81 X86_BR_SYSRET = 1 << 5, /* syscall return */ 82 X86_BR_INT = 1 << 6, /* sw interrupt */ 83 X86_BR_IRET = 1 << 7, /* return from interrupt */ 84 X86_BR_JCC = 1 << 8, /* conditional */ 85 X86_BR_JMP = 1 << 9, /* jump */ 86 X86_BR_IRQ = 1 << 10,/* hw interrupt or trap or fault */ 87 X86_BR_IND_CALL = 1 << 11,/* indirect calls */ 88 X86_BR_ABORT = 1 << 12,/* transaction abort */ 89 X86_BR_IN_TX = 1 << 13,/* in transaction */ 90 X86_BR_NO_TX = 1 << 14,/* not in transaction */ 91 X86_BR_ZERO_CALL = 1 << 15,/* zero length call */ 92 X86_BR_CALL_STACK = 1 << 16,/* call stack */ 93 X86_BR_IND_JMP = 1 << 17,/* indirect jump */ 94 95 X86_BR_TYPE_SAVE = 1 << 18,/* indicate to save branch type */ 96 97 }; 98 99 #define X86_BR_PLM (X86_BR_USER | X86_BR_KERNEL) 100 #define X86_BR_ANYTX (X86_BR_NO_TX | X86_BR_IN_TX) 101 102 #define X86_BR_ANY \ 103 (X86_BR_CALL |\ 104 X86_BR_RET |\ 105 X86_BR_SYSCALL |\ 106 X86_BR_SYSRET |\ 107 X86_BR_INT |\ 108 X86_BR_IRET |\ 109 X86_BR_JCC |\ 110 X86_BR_JMP |\ 111 X86_BR_IRQ |\ 112 X86_BR_ABORT |\ 113 X86_BR_IND_CALL |\ 114 X86_BR_IND_JMP |\ 115 X86_BR_ZERO_CALL) 116 117 #define X86_BR_ALL (X86_BR_PLM | X86_BR_ANY) 118 119 #define X86_BR_ANY_CALL \ 120 (X86_BR_CALL |\ 121 X86_BR_IND_CALL |\ 122 X86_BR_ZERO_CALL |\ 123 X86_BR_SYSCALL |\ 124 X86_BR_IRQ |\ 125 X86_BR_INT) 126 127 /* 128 * Intel LBR_CTL bits 129 * 130 * Hardware branch filter for Arch LBR 131 */ 132 #define ARCH_LBR_KERNEL_BIT 1 /* capture at ring0 */ 133 #define ARCH_LBR_USER_BIT 2 /* capture at ring > 0 */ 134 #define ARCH_LBR_CALL_STACK_BIT 3 /* enable call stack */ 135 #define ARCH_LBR_JCC_BIT 16 /* capture conditional branches */ 136 #define ARCH_LBR_REL_JMP_BIT 17 /* capture relative jumps */ 137 #define ARCH_LBR_IND_JMP_BIT 18 /* capture indirect jumps */ 138 #define ARCH_LBR_REL_CALL_BIT 19 /* capture relative calls */ 139 #define ARCH_LBR_IND_CALL_BIT 20 /* capture indirect calls */ 140 #define ARCH_LBR_RETURN_BIT 21 /* capture near returns */ 141 #define ARCH_LBR_OTHER_BRANCH_BIT 22 /* capture other branches */ 142 143 #define ARCH_LBR_KERNEL (1ULL << ARCH_LBR_KERNEL_BIT) 144 #define ARCH_LBR_USER (1ULL << ARCH_LBR_USER_BIT) 145 #define ARCH_LBR_CALL_STACK (1ULL << ARCH_LBR_CALL_STACK_BIT) 146 #define ARCH_LBR_JCC (1ULL << ARCH_LBR_JCC_BIT) 147 #define ARCH_LBR_REL_JMP (1ULL << ARCH_LBR_REL_JMP_BIT) 148 #define ARCH_LBR_IND_JMP (1ULL << ARCH_LBR_IND_JMP_BIT) 149 #define ARCH_LBR_REL_CALL (1ULL << ARCH_LBR_REL_CALL_BIT) 150 #define ARCH_LBR_IND_CALL (1ULL << ARCH_LBR_IND_CALL_BIT) 151 #define ARCH_LBR_RETURN (1ULL << ARCH_LBR_RETURN_BIT) 152 #define ARCH_LBR_OTHER_BRANCH (1ULL << ARCH_LBR_OTHER_BRANCH_BIT) 153 154 #define ARCH_LBR_ANY \ 155 (ARCH_LBR_JCC |\ 156 ARCH_LBR_REL_JMP |\ 157 ARCH_LBR_IND_JMP |\ 158 ARCH_LBR_REL_CALL |\ 159 ARCH_LBR_IND_CALL |\ 160 ARCH_LBR_RETURN |\ 161 ARCH_LBR_OTHER_BRANCH) 162 163 #define ARCH_LBR_CTL_MASK 0x7f000e 164 165 static void intel_pmu_lbr_filter(struct cpu_hw_events *cpuc); 166 167 static __always_inline bool is_lbr_call_stack_bit_set(u64 config) 168 { 169 if (static_cpu_has(X86_FEATURE_ARCH_LBR)) 170 return !!(config & ARCH_LBR_CALL_STACK); 171 172 return !!(config & LBR_CALL_STACK); 173 } 174 175 /* 176 * We only support LBR implementations that have FREEZE_LBRS_ON_PMI 177 * otherwise it becomes near impossible to get a reliable stack. 178 */ 179 180 static void __intel_pmu_lbr_enable(bool pmi) 181 { 182 struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); 183 u64 debugctl, lbr_select = 0, orig_debugctl; 184 185 /* 186 * No need to unfreeze manually, as v4 can do that as part 187 * of the GLOBAL_STATUS ack. 188 */ 189 if (pmi && x86_pmu.version >= 4) 190 return; 191 192 /* 193 * No need to reprogram LBR_SELECT in a PMI, as it 194 * did not change. 195 */ 196 if (cpuc->lbr_sel) 197 lbr_select = cpuc->lbr_sel->config & x86_pmu.lbr_sel_mask; 198 if (!static_cpu_has(X86_FEATURE_ARCH_LBR) && !pmi && cpuc->lbr_sel) 199 wrmsrl(MSR_LBR_SELECT, lbr_select); 200 201 rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctl); 202 orig_debugctl = debugctl; 203 204 if (!static_cpu_has(X86_FEATURE_ARCH_LBR)) 205 debugctl |= DEBUGCTLMSR_LBR; 206 /* 207 * LBR callstack does not work well with FREEZE_LBRS_ON_PMI. 208 * If FREEZE_LBRS_ON_PMI is set, PMI near call/return instructions 209 * may cause superfluous increase/decrease of LBR_TOS. 210 */ 211 if (is_lbr_call_stack_bit_set(lbr_select)) 212 debugctl &= ~DEBUGCTLMSR_FREEZE_LBRS_ON_PMI; 213 else 214 debugctl |= DEBUGCTLMSR_FREEZE_LBRS_ON_PMI; 215 216 if (orig_debugctl != debugctl) 217 wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctl); 218 219 if (static_cpu_has(X86_FEATURE_ARCH_LBR)) 220 wrmsrl(MSR_ARCH_LBR_CTL, lbr_select | ARCH_LBR_CTL_LBREN); 221 } 222 223 void intel_pmu_lbr_reset_32(void) 224 { 225 int i; 226 227 for (i = 0; i < x86_pmu.lbr_nr; i++) 228 wrmsrl(x86_pmu.lbr_from + i, 0); 229 } 230 231 void intel_pmu_lbr_reset_64(void) 232 { 233 int i; 234 235 for (i = 0; i < x86_pmu.lbr_nr; i++) { 236 wrmsrl(x86_pmu.lbr_from + i, 0); 237 wrmsrl(x86_pmu.lbr_to + i, 0); 238 if (x86_pmu.lbr_has_info) 239 wrmsrl(x86_pmu.lbr_info + i, 0); 240 } 241 } 242 243 static void intel_pmu_arch_lbr_reset(void) 244 { 245 /* Write to ARCH_LBR_DEPTH MSR, all LBR entries are reset to 0 */ 246 wrmsrl(MSR_ARCH_LBR_DEPTH, x86_pmu.lbr_nr); 247 } 248 249 void intel_pmu_lbr_reset(void) 250 { 251 struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); 252 253 if (!x86_pmu.lbr_nr) 254 return; 255 256 x86_pmu.lbr_reset(); 257 258 cpuc->last_task_ctx = NULL; 259 cpuc->last_log_id = 0; 260 if (!static_cpu_has(X86_FEATURE_ARCH_LBR) && cpuc->lbr_select) 261 wrmsrl(MSR_LBR_SELECT, 0); 262 } 263 264 /* 265 * TOS = most recently recorded branch 266 */ 267 static inline u64 intel_pmu_lbr_tos(void) 268 { 269 u64 tos; 270 271 rdmsrl(x86_pmu.lbr_tos, tos); 272 return tos; 273 } 274 275 enum { 276 LBR_NONE, 277 LBR_VALID, 278 }; 279 280 /* 281 * For formats with LBR_TSX flags (e.g. LBR_FORMAT_EIP_FLAGS2), bits 61:62 in 282 * MSR_LAST_BRANCH_FROM_x are the TSX flags when TSX is supported, but when 283 * TSX is not supported they have no consistent behavior: 284 * 285 * - For wrmsr(), bits 61:62 are considered part of the sign extension. 286 * - For HW updates (branch captures) bits 61:62 are always OFF and are not 287 * part of the sign extension. 288 * 289 * Therefore, if: 290 * 291 * 1) LBR has TSX format 292 * 2) CPU has no TSX support enabled 293 * 294 * ... then any value passed to wrmsr() must be sign extended to 63 bits and any 295 * value from rdmsr() must be converted to have a 61 bits sign extension, 296 * ignoring the TSX flags. 297 */ 298 static inline bool lbr_from_signext_quirk_needed(void) 299 { 300 bool tsx_support = boot_cpu_has(X86_FEATURE_HLE) || 301 boot_cpu_has(X86_FEATURE_RTM); 302 303 return !tsx_support && x86_pmu.lbr_has_tsx; 304 } 305 306 static DEFINE_STATIC_KEY_FALSE(lbr_from_quirk_key); 307 308 /* If quirk is enabled, ensure sign extension is 63 bits: */ 309 inline u64 lbr_from_signext_quirk_wr(u64 val) 310 { 311 if (static_branch_unlikely(&lbr_from_quirk_key)) { 312 /* 313 * Sign extend into bits 61:62 while preserving bit 63. 314 * 315 * Quirk is enabled when TSX is disabled. Therefore TSX bits 316 * in val are always OFF and must be changed to be sign 317 * extension bits. Since bits 59:60 are guaranteed to be 318 * part of the sign extension bits, we can just copy them 319 * to 61:62. 320 */ 321 val |= (LBR_FROM_SIGNEXT_2MSB & val) << 2; 322 } 323 return val; 324 } 325 326 /* 327 * If quirk is needed, ensure sign extension is 61 bits: 328 */ 329 static u64 lbr_from_signext_quirk_rd(u64 val) 330 { 331 if (static_branch_unlikely(&lbr_from_quirk_key)) { 332 /* 333 * Quirk is on when TSX is not enabled. Therefore TSX 334 * flags must be read as OFF. 335 */ 336 val &= ~(LBR_FROM_FLAG_IN_TX | LBR_FROM_FLAG_ABORT); 337 } 338 return val; 339 } 340 341 static __always_inline void wrlbr_from(unsigned int idx, u64 val) 342 { 343 val = lbr_from_signext_quirk_wr(val); 344 wrmsrl(x86_pmu.lbr_from + idx, val); 345 } 346 347 static __always_inline void wrlbr_to(unsigned int idx, u64 val) 348 { 349 wrmsrl(x86_pmu.lbr_to + idx, val); 350 } 351 352 static __always_inline void wrlbr_info(unsigned int idx, u64 val) 353 { 354 wrmsrl(x86_pmu.lbr_info + idx, val); 355 } 356 357 static __always_inline u64 rdlbr_from(unsigned int idx, struct lbr_entry *lbr) 358 { 359 u64 val; 360 361 if (lbr) 362 return lbr->from; 363 364 rdmsrl(x86_pmu.lbr_from + idx, val); 365 366 return lbr_from_signext_quirk_rd(val); 367 } 368 369 static __always_inline u64 rdlbr_to(unsigned int idx, struct lbr_entry *lbr) 370 { 371 u64 val; 372 373 if (lbr) 374 return lbr->to; 375 376 rdmsrl(x86_pmu.lbr_to + idx, val); 377 378 return val; 379 } 380 381 static __always_inline u64 rdlbr_info(unsigned int idx, struct lbr_entry *lbr) 382 { 383 u64 val; 384 385 if (lbr) 386 return lbr->info; 387 388 rdmsrl(x86_pmu.lbr_info + idx, val); 389 390 return val; 391 } 392 393 static inline void 394 wrlbr_all(struct lbr_entry *lbr, unsigned int idx, bool need_info) 395 { 396 wrlbr_from(idx, lbr->from); 397 wrlbr_to(idx, lbr->to); 398 if (need_info) 399 wrlbr_info(idx, lbr->info); 400 } 401 402 static inline bool 403 rdlbr_all(struct lbr_entry *lbr, unsigned int idx, bool need_info) 404 { 405 u64 from = rdlbr_from(idx, NULL); 406 407 /* Don't read invalid entry */ 408 if (!from) 409 return false; 410 411 lbr->from = from; 412 lbr->to = rdlbr_to(idx, NULL); 413 if (need_info) 414 lbr->info = rdlbr_info(idx, NULL); 415 416 return true; 417 } 418 419 void intel_pmu_lbr_restore(void *ctx) 420 { 421 struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); 422 struct x86_perf_task_context *task_ctx = ctx; 423 bool need_info = x86_pmu.lbr_has_info; 424 u64 tos = task_ctx->tos; 425 unsigned lbr_idx, mask; 426 int i; 427 428 mask = x86_pmu.lbr_nr - 1; 429 for (i = 0; i < task_ctx->valid_lbrs; i++) { 430 lbr_idx = (tos - i) & mask; 431 wrlbr_all(&task_ctx->lbr[i], lbr_idx, need_info); 432 } 433 434 for (; i < x86_pmu.lbr_nr; i++) { 435 lbr_idx = (tos - i) & mask; 436 wrlbr_from(lbr_idx, 0); 437 wrlbr_to(lbr_idx, 0); 438 if (need_info) 439 wrlbr_info(lbr_idx, 0); 440 } 441 442 wrmsrl(x86_pmu.lbr_tos, tos); 443 444 if (cpuc->lbr_select) 445 wrmsrl(MSR_LBR_SELECT, task_ctx->lbr_sel); 446 } 447 448 static void intel_pmu_arch_lbr_restore(void *ctx) 449 { 450 struct x86_perf_task_context_arch_lbr *task_ctx = ctx; 451 struct lbr_entry *entries = task_ctx->entries; 452 int i; 453 454 /* Fast reset the LBRs before restore if the call stack is not full. */ 455 if (!entries[x86_pmu.lbr_nr - 1].from) 456 intel_pmu_arch_lbr_reset(); 457 458 for (i = 0; i < x86_pmu.lbr_nr; i++) { 459 if (!entries[i].from) 460 break; 461 wrlbr_all(&entries[i], i, true); 462 } 463 } 464 465 /* 466 * Restore the Architecture LBR state from the xsave area in the perf 467 * context data for the task via the XRSTORS instruction. 468 */ 469 static void intel_pmu_arch_lbr_xrstors(void *ctx) 470 { 471 struct x86_perf_task_context_arch_lbr_xsave *task_ctx = ctx; 472 473 xrstors(&task_ctx->xsave, XFEATURE_MASK_LBR); 474 } 475 476 static __always_inline bool lbr_is_reset_in_cstate(void *ctx) 477 { 478 if (static_cpu_has(X86_FEATURE_ARCH_LBR)) 479 return x86_pmu.lbr_deep_c_reset && !rdlbr_from(0, NULL); 480 481 return !rdlbr_from(((struct x86_perf_task_context *)ctx)->tos, NULL); 482 } 483 484 static void __intel_pmu_lbr_restore(void *ctx) 485 { 486 struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); 487 488 if (task_context_opt(ctx)->lbr_callstack_users == 0 || 489 task_context_opt(ctx)->lbr_stack_state == LBR_NONE) { 490 intel_pmu_lbr_reset(); 491 return; 492 } 493 494 /* 495 * Does not restore the LBR registers, if 496 * - No one else touched them, and 497 * - Was not cleared in Cstate 498 */ 499 if ((ctx == cpuc->last_task_ctx) && 500 (task_context_opt(ctx)->log_id == cpuc->last_log_id) && 501 !lbr_is_reset_in_cstate(ctx)) { 502 task_context_opt(ctx)->lbr_stack_state = LBR_NONE; 503 return; 504 } 505 506 x86_pmu.lbr_restore(ctx); 507 508 task_context_opt(ctx)->lbr_stack_state = LBR_NONE; 509 } 510 511 void intel_pmu_lbr_save(void *ctx) 512 { 513 struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); 514 struct x86_perf_task_context *task_ctx = ctx; 515 bool need_info = x86_pmu.lbr_has_info; 516 unsigned lbr_idx, mask; 517 u64 tos; 518 int i; 519 520 mask = x86_pmu.lbr_nr - 1; 521 tos = intel_pmu_lbr_tos(); 522 for (i = 0; i < x86_pmu.lbr_nr; i++) { 523 lbr_idx = (tos - i) & mask; 524 if (!rdlbr_all(&task_ctx->lbr[i], lbr_idx, need_info)) 525 break; 526 } 527 task_ctx->valid_lbrs = i; 528 task_ctx->tos = tos; 529 530 if (cpuc->lbr_select) 531 rdmsrl(MSR_LBR_SELECT, task_ctx->lbr_sel); 532 } 533 534 static void intel_pmu_arch_lbr_save(void *ctx) 535 { 536 struct x86_perf_task_context_arch_lbr *task_ctx = ctx; 537 struct lbr_entry *entries = task_ctx->entries; 538 int i; 539 540 for (i = 0; i < x86_pmu.lbr_nr; i++) { 541 if (!rdlbr_all(&entries[i], i, true)) 542 break; 543 } 544 545 /* LBR call stack is not full. Reset is required in restore. */ 546 if (i < x86_pmu.lbr_nr) 547 entries[x86_pmu.lbr_nr - 1].from = 0; 548 } 549 550 /* 551 * Save the Architecture LBR state to the xsave area in the perf 552 * context data for the task via the XSAVES instruction. 553 */ 554 static void intel_pmu_arch_lbr_xsaves(void *ctx) 555 { 556 struct x86_perf_task_context_arch_lbr_xsave *task_ctx = ctx; 557 558 xsaves(&task_ctx->xsave, XFEATURE_MASK_LBR); 559 } 560 561 static void __intel_pmu_lbr_save(void *ctx) 562 { 563 struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); 564 565 if (task_context_opt(ctx)->lbr_callstack_users == 0) { 566 task_context_opt(ctx)->lbr_stack_state = LBR_NONE; 567 return; 568 } 569 570 x86_pmu.lbr_save(ctx); 571 572 task_context_opt(ctx)->lbr_stack_state = LBR_VALID; 573 574 cpuc->last_task_ctx = ctx; 575 cpuc->last_log_id = ++task_context_opt(ctx)->log_id; 576 } 577 578 void intel_pmu_lbr_swap_task_ctx(struct perf_event_context *prev, 579 struct perf_event_context *next) 580 { 581 void *prev_ctx_data, *next_ctx_data; 582 583 swap(prev->task_ctx_data, next->task_ctx_data); 584 585 /* 586 * Architecture specific synchronization makes sense in 587 * case both prev->task_ctx_data and next->task_ctx_data 588 * pointers are allocated. 589 */ 590 591 prev_ctx_data = next->task_ctx_data; 592 next_ctx_data = prev->task_ctx_data; 593 594 if (!prev_ctx_data || !next_ctx_data) 595 return; 596 597 swap(task_context_opt(prev_ctx_data)->lbr_callstack_users, 598 task_context_opt(next_ctx_data)->lbr_callstack_users); 599 } 600 601 void intel_pmu_lbr_sched_task(struct perf_event_context *ctx, bool sched_in) 602 { 603 struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); 604 void *task_ctx; 605 606 if (!cpuc->lbr_users) 607 return; 608 609 /* 610 * If LBR callstack feature is enabled and the stack was saved when 611 * the task was scheduled out, restore the stack. Otherwise flush 612 * the LBR stack. 613 */ 614 task_ctx = ctx ? ctx->task_ctx_data : NULL; 615 if (task_ctx) { 616 if (sched_in) 617 __intel_pmu_lbr_restore(task_ctx); 618 else 619 __intel_pmu_lbr_save(task_ctx); 620 return; 621 } 622 623 /* 624 * Since a context switch can flip the address space and LBR entries 625 * are not tagged with an identifier, we need to wipe the LBR, even for 626 * per-cpu events. You simply cannot resolve the branches from the old 627 * address space. 628 */ 629 if (sched_in) 630 intel_pmu_lbr_reset(); 631 } 632 633 static inline bool branch_user_callstack(unsigned br_sel) 634 { 635 return (br_sel & X86_BR_USER) && (br_sel & X86_BR_CALL_STACK); 636 } 637 638 void intel_pmu_lbr_add(struct perf_event *event) 639 { 640 struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); 641 642 if (!x86_pmu.lbr_nr) 643 return; 644 645 if (event->hw.flags & PERF_X86_EVENT_LBR_SELECT) 646 cpuc->lbr_select = 1; 647 648 cpuc->br_sel = event->hw.branch_reg.reg; 649 650 if (branch_user_callstack(cpuc->br_sel) && event->ctx->task_ctx_data) 651 task_context_opt(event->ctx->task_ctx_data)->lbr_callstack_users++; 652 653 /* 654 * Request pmu::sched_task() callback, which will fire inside the 655 * regular perf event scheduling, so that call will: 656 * 657 * - restore or wipe; when LBR-callstack, 658 * - wipe; otherwise, 659 * 660 * when this is from __perf_event_task_sched_in(). 661 * 662 * However, if this is from perf_install_in_context(), no such callback 663 * will follow and we'll need to reset the LBR here if this is the 664 * first LBR event. 665 * 666 * The problem is, we cannot tell these cases apart... but we can 667 * exclude the biggest chunk of cases by looking at 668 * event->total_time_running. An event that has accrued runtime cannot 669 * be 'new'. Conversely, a new event can get installed through the 670 * context switch path for the first time. 671 */ 672 if (x86_pmu.intel_cap.pebs_baseline && event->attr.precise_ip > 0) 673 cpuc->lbr_pebs_users++; 674 perf_sched_cb_inc(event->ctx->pmu); 675 if (!cpuc->lbr_users++ && !event->total_time_running) 676 intel_pmu_lbr_reset(); 677 } 678 679 void release_lbr_buffers(void) 680 { 681 struct kmem_cache *kmem_cache; 682 struct cpu_hw_events *cpuc; 683 int cpu; 684 685 if (!static_cpu_has(X86_FEATURE_ARCH_LBR)) 686 return; 687 688 for_each_possible_cpu(cpu) { 689 cpuc = per_cpu_ptr(&cpu_hw_events, cpu); 690 kmem_cache = x86_get_pmu(cpu)->task_ctx_cache; 691 if (kmem_cache && cpuc->lbr_xsave) { 692 kmem_cache_free(kmem_cache, cpuc->lbr_xsave); 693 cpuc->lbr_xsave = NULL; 694 } 695 } 696 } 697 698 void reserve_lbr_buffers(void) 699 { 700 struct kmem_cache *kmem_cache; 701 struct cpu_hw_events *cpuc; 702 int cpu; 703 704 if (!static_cpu_has(X86_FEATURE_ARCH_LBR)) 705 return; 706 707 for_each_possible_cpu(cpu) { 708 cpuc = per_cpu_ptr(&cpu_hw_events, cpu); 709 kmem_cache = x86_get_pmu(cpu)->task_ctx_cache; 710 if (!kmem_cache || cpuc->lbr_xsave) 711 continue; 712 713 cpuc->lbr_xsave = kmem_cache_alloc_node(kmem_cache, 714 GFP_KERNEL | __GFP_ZERO, 715 cpu_to_node(cpu)); 716 } 717 } 718 719 void intel_pmu_lbr_del(struct perf_event *event) 720 { 721 struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); 722 723 if (!x86_pmu.lbr_nr) 724 return; 725 726 if (branch_user_callstack(cpuc->br_sel) && 727 event->ctx->task_ctx_data) 728 task_context_opt(event->ctx->task_ctx_data)->lbr_callstack_users--; 729 730 if (event->hw.flags & PERF_X86_EVENT_LBR_SELECT) 731 cpuc->lbr_select = 0; 732 733 if (x86_pmu.intel_cap.pebs_baseline && event->attr.precise_ip > 0) 734 cpuc->lbr_pebs_users--; 735 cpuc->lbr_users--; 736 WARN_ON_ONCE(cpuc->lbr_users < 0); 737 WARN_ON_ONCE(cpuc->lbr_pebs_users < 0); 738 perf_sched_cb_dec(event->ctx->pmu); 739 } 740 741 static inline bool vlbr_exclude_host(void) 742 { 743 struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); 744 745 return test_bit(INTEL_PMC_IDX_FIXED_VLBR, 746 (unsigned long *)&cpuc->intel_ctrl_guest_mask); 747 } 748 749 void intel_pmu_lbr_enable_all(bool pmi) 750 { 751 struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); 752 753 if (cpuc->lbr_users && !vlbr_exclude_host()) 754 __intel_pmu_lbr_enable(pmi); 755 } 756 757 void intel_pmu_lbr_disable_all(void) 758 { 759 struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); 760 761 if (cpuc->lbr_users && !vlbr_exclude_host()) { 762 if (static_cpu_has(X86_FEATURE_ARCH_LBR)) 763 return __intel_pmu_arch_lbr_disable(); 764 765 __intel_pmu_lbr_disable(); 766 } 767 } 768 769 void intel_pmu_lbr_read_32(struct cpu_hw_events *cpuc) 770 { 771 unsigned long mask = x86_pmu.lbr_nr - 1; 772 u64 tos = intel_pmu_lbr_tos(); 773 int i; 774 775 for (i = 0; i < x86_pmu.lbr_nr; i++) { 776 unsigned long lbr_idx = (tos - i) & mask; 777 union { 778 struct { 779 u32 from; 780 u32 to; 781 }; 782 u64 lbr; 783 } msr_lastbranch; 784 785 rdmsrl(x86_pmu.lbr_from + lbr_idx, msr_lastbranch.lbr); 786 787 cpuc->lbr_entries[i].from = msr_lastbranch.from; 788 cpuc->lbr_entries[i].to = msr_lastbranch.to; 789 cpuc->lbr_entries[i].mispred = 0; 790 cpuc->lbr_entries[i].predicted = 0; 791 cpuc->lbr_entries[i].in_tx = 0; 792 cpuc->lbr_entries[i].abort = 0; 793 cpuc->lbr_entries[i].cycles = 0; 794 cpuc->lbr_entries[i].type = 0; 795 cpuc->lbr_entries[i].reserved = 0; 796 } 797 cpuc->lbr_stack.nr = i; 798 cpuc->lbr_stack.hw_idx = tos; 799 } 800 801 /* 802 * Due to lack of segmentation in Linux the effective address (offset) 803 * is the same as the linear address, allowing us to merge the LIP and EIP 804 * LBR formats. 805 */ 806 void intel_pmu_lbr_read_64(struct cpu_hw_events *cpuc) 807 { 808 bool need_info = false, call_stack = false; 809 unsigned long mask = x86_pmu.lbr_nr - 1; 810 u64 tos = intel_pmu_lbr_tos(); 811 int i; 812 int out = 0; 813 int num = x86_pmu.lbr_nr; 814 815 if (cpuc->lbr_sel) { 816 need_info = !(cpuc->lbr_sel->config & LBR_NO_INFO); 817 if (cpuc->lbr_sel->config & LBR_CALL_STACK) 818 call_stack = true; 819 } 820 821 for (i = 0; i < num; i++) { 822 unsigned long lbr_idx = (tos - i) & mask; 823 u64 from, to, mis = 0, pred = 0, in_tx = 0, abort = 0; 824 u16 cycles = 0; 825 826 from = rdlbr_from(lbr_idx, NULL); 827 to = rdlbr_to(lbr_idx, NULL); 828 829 /* 830 * Read LBR call stack entries 831 * until invalid entry (0s) is detected. 832 */ 833 if (call_stack && !from) 834 break; 835 836 if (x86_pmu.lbr_has_info) { 837 if (need_info) { 838 u64 info; 839 840 info = rdlbr_info(lbr_idx, NULL); 841 mis = !!(info & LBR_INFO_MISPRED); 842 pred = !mis; 843 cycles = (info & LBR_INFO_CYCLES); 844 if (x86_pmu.lbr_has_tsx) { 845 in_tx = !!(info & LBR_INFO_IN_TX); 846 abort = !!(info & LBR_INFO_ABORT); 847 } 848 } 849 } else { 850 int skip = 0; 851 852 if (x86_pmu.lbr_from_flags) { 853 mis = !!(from & LBR_FROM_FLAG_MISPRED); 854 pred = !mis; 855 skip = 1; 856 } 857 if (x86_pmu.lbr_has_tsx) { 858 in_tx = !!(from & LBR_FROM_FLAG_IN_TX); 859 abort = !!(from & LBR_FROM_FLAG_ABORT); 860 skip = 3; 861 } 862 from = (u64)((((s64)from) << skip) >> skip); 863 864 if (x86_pmu.lbr_to_cycles) { 865 cycles = ((to >> 48) & LBR_INFO_CYCLES); 866 to = (u64)((((s64)to) << 16) >> 16); 867 } 868 } 869 870 /* 871 * Some CPUs report duplicated abort records, 872 * with the second entry not having an abort bit set. 873 * Skip them here. This loop runs backwards, 874 * so we need to undo the previous record. 875 * If the abort just happened outside the window 876 * the extra entry cannot be removed. 877 */ 878 if (abort && x86_pmu.lbr_double_abort && out > 0) 879 out--; 880 881 cpuc->lbr_entries[out].from = from; 882 cpuc->lbr_entries[out].to = to; 883 cpuc->lbr_entries[out].mispred = mis; 884 cpuc->lbr_entries[out].predicted = pred; 885 cpuc->lbr_entries[out].in_tx = in_tx; 886 cpuc->lbr_entries[out].abort = abort; 887 cpuc->lbr_entries[out].cycles = cycles; 888 cpuc->lbr_entries[out].type = 0; 889 cpuc->lbr_entries[out].reserved = 0; 890 out++; 891 } 892 cpuc->lbr_stack.nr = out; 893 cpuc->lbr_stack.hw_idx = tos; 894 } 895 896 static DEFINE_STATIC_KEY_FALSE(x86_lbr_mispred); 897 static DEFINE_STATIC_KEY_FALSE(x86_lbr_cycles); 898 static DEFINE_STATIC_KEY_FALSE(x86_lbr_type); 899 900 static __always_inline int get_lbr_br_type(u64 info) 901 { 902 int type = 0; 903 904 if (static_branch_likely(&x86_lbr_type)) 905 type = (info & LBR_INFO_BR_TYPE) >> LBR_INFO_BR_TYPE_OFFSET; 906 907 return type; 908 } 909 910 static __always_inline bool get_lbr_mispred(u64 info) 911 { 912 bool mispred = 0; 913 914 if (static_branch_likely(&x86_lbr_mispred)) 915 mispred = !!(info & LBR_INFO_MISPRED); 916 917 return mispred; 918 } 919 920 static __always_inline u16 get_lbr_cycles(u64 info) 921 { 922 u16 cycles = info & LBR_INFO_CYCLES; 923 924 if (static_cpu_has(X86_FEATURE_ARCH_LBR) && 925 (!static_branch_likely(&x86_lbr_cycles) || 926 !(info & LBR_INFO_CYC_CNT_VALID))) 927 cycles = 0; 928 929 return cycles; 930 } 931 932 static void intel_pmu_store_lbr(struct cpu_hw_events *cpuc, 933 struct lbr_entry *entries) 934 { 935 struct perf_branch_entry *e; 936 struct lbr_entry *lbr; 937 u64 from, to, info; 938 int i; 939 940 for (i = 0; i < x86_pmu.lbr_nr; i++) { 941 lbr = entries ? &entries[i] : NULL; 942 e = &cpuc->lbr_entries[i]; 943 944 from = rdlbr_from(i, lbr); 945 /* 946 * Read LBR entries until invalid entry (0s) is detected. 947 */ 948 if (!from) 949 break; 950 951 to = rdlbr_to(i, lbr); 952 info = rdlbr_info(i, lbr); 953 954 e->from = from; 955 e->to = to; 956 e->mispred = get_lbr_mispred(info); 957 e->predicted = !e->mispred; 958 e->in_tx = !!(info & LBR_INFO_IN_TX); 959 e->abort = !!(info & LBR_INFO_ABORT); 960 e->cycles = get_lbr_cycles(info); 961 e->type = get_lbr_br_type(info); 962 e->reserved = 0; 963 } 964 965 cpuc->lbr_stack.nr = i; 966 } 967 968 static void intel_pmu_arch_lbr_read(struct cpu_hw_events *cpuc) 969 { 970 intel_pmu_store_lbr(cpuc, NULL); 971 } 972 973 static void intel_pmu_arch_lbr_read_xsave(struct cpu_hw_events *cpuc) 974 { 975 struct x86_perf_task_context_arch_lbr_xsave *xsave = cpuc->lbr_xsave; 976 977 if (!xsave) { 978 intel_pmu_store_lbr(cpuc, NULL); 979 return; 980 } 981 xsaves(&xsave->xsave, XFEATURE_MASK_LBR); 982 983 intel_pmu_store_lbr(cpuc, xsave->lbr.entries); 984 } 985 986 void intel_pmu_lbr_read(void) 987 { 988 struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); 989 990 /* 991 * Don't read when all LBRs users are using adaptive PEBS. 992 * 993 * This could be smarter and actually check the event, 994 * but this simple approach seems to work for now. 995 */ 996 if (!cpuc->lbr_users || vlbr_exclude_host() || 997 cpuc->lbr_users == cpuc->lbr_pebs_users) 998 return; 999 1000 x86_pmu.lbr_read(cpuc); 1001 1002 intel_pmu_lbr_filter(cpuc); 1003 } 1004 1005 /* 1006 * SW filter is used: 1007 * - in case there is no HW filter 1008 * - in case the HW filter has errata or limitations 1009 */ 1010 static int intel_pmu_setup_sw_lbr_filter(struct perf_event *event) 1011 { 1012 u64 br_type = event->attr.branch_sample_type; 1013 int mask = 0; 1014 1015 if (br_type & PERF_SAMPLE_BRANCH_USER) 1016 mask |= X86_BR_USER; 1017 1018 if (br_type & PERF_SAMPLE_BRANCH_KERNEL) 1019 mask |= X86_BR_KERNEL; 1020 1021 /* we ignore BRANCH_HV here */ 1022 1023 if (br_type & PERF_SAMPLE_BRANCH_ANY) 1024 mask |= X86_BR_ANY; 1025 1026 if (br_type & PERF_SAMPLE_BRANCH_ANY_CALL) 1027 mask |= X86_BR_ANY_CALL; 1028 1029 if (br_type & PERF_SAMPLE_BRANCH_ANY_RETURN) 1030 mask |= X86_BR_RET | X86_BR_IRET | X86_BR_SYSRET; 1031 1032 if (br_type & PERF_SAMPLE_BRANCH_IND_CALL) 1033 mask |= X86_BR_IND_CALL; 1034 1035 if (br_type & PERF_SAMPLE_BRANCH_ABORT_TX) 1036 mask |= X86_BR_ABORT; 1037 1038 if (br_type & PERF_SAMPLE_BRANCH_IN_TX) 1039 mask |= X86_BR_IN_TX; 1040 1041 if (br_type & PERF_SAMPLE_BRANCH_NO_TX) 1042 mask |= X86_BR_NO_TX; 1043 1044 if (br_type & PERF_SAMPLE_BRANCH_COND) 1045 mask |= X86_BR_JCC; 1046 1047 if (br_type & PERF_SAMPLE_BRANCH_CALL_STACK) { 1048 if (!x86_pmu_has_lbr_callstack()) 1049 return -EOPNOTSUPP; 1050 if (mask & ~(X86_BR_USER | X86_BR_KERNEL)) 1051 return -EINVAL; 1052 mask |= X86_BR_CALL | X86_BR_IND_CALL | X86_BR_RET | 1053 X86_BR_CALL_STACK; 1054 } 1055 1056 if (br_type & PERF_SAMPLE_BRANCH_IND_JUMP) 1057 mask |= X86_BR_IND_JMP; 1058 1059 if (br_type & PERF_SAMPLE_BRANCH_CALL) 1060 mask |= X86_BR_CALL | X86_BR_ZERO_CALL; 1061 1062 if (br_type & PERF_SAMPLE_BRANCH_TYPE_SAVE) 1063 mask |= X86_BR_TYPE_SAVE; 1064 1065 /* 1066 * stash actual user request into reg, it may 1067 * be used by fixup code for some CPU 1068 */ 1069 event->hw.branch_reg.reg = mask; 1070 return 0; 1071 } 1072 1073 /* 1074 * setup the HW LBR filter 1075 * Used only when available, may not be enough to disambiguate 1076 * all branches, may need the help of the SW filter 1077 */ 1078 static int intel_pmu_setup_hw_lbr_filter(struct perf_event *event) 1079 { 1080 struct hw_perf_event_extra *reg; 1081 u64 br_type = event->attr.branch_sample_type; 1082 u64 mask = 0, v; 1083 int i; 1084 1085 for (i = 0; i < PERF_SAMPLE_BRANCH_MAX_SHIFT; i++) { 1086 if (!(br_type & (1ULL << i))) 1087 continue; 1088 1089 v = x86_pmu.lbr_sel_map[i]; 1090 if (v == LBR_NOT_SUPP) 1091 return -EOPNOTSUPP; 1092 1093 if (v != LBR_IGN) 1094 mask |= v; 1095 } 1096 1097 reg = &event->hw.branch_reg; 1098 reg->idx = EXTRA_REG_LBR; 1099 1100 if (static_cpu_has(X86_FEATURE_ARCH_LBR)) { 1101 reg->config = mask; 1102 return 0; 1103 } 1104 1105 /* 1106 * The first 9 bits (LBR_SEL_MASK) in LBR_SELECT operate 1107 * in suppress mode. So LBR_SELECT should be set to 1108 * (~mask & LBR_SEL_MASK) | (mask & ~LBR_SEL_MASK) 1109 * But the 10th bit LBR_CALL_STACK does not operate 1110 * in suppress mode. 1111 */ 1112 reg->config = mask ^ (x86_pmu.lbr_sel_mask & ~LBR_CALL_STACK); 1113 1114 if ((br_type & PERF_SAMPLE_BRANCH_NO_CYCLES) && 1115 (br_type & PERF_SAMPLE_BRANCH_NO_FLAGS) && 1116 x86_pmu.lbr_has_info) 1117 reg->config |= LBR_NO_INFO; 1118 1119 return 0; 1120 } 1121 1122 int intel_pmu_setup_lbr_filter(struct perf_event *event) 1123 { 1124 int ret = 0; 1125 1126 /* 1127 * no LBR on this PMU 1128 */ 1129 if (!x86_pmu.lbr_nr) 1130 return -EOPNOTSUPP; 1131 1132 /* 1133 * setup SW LBR filter 1134 */ 1135 ret = intel_pmu_setup_sw_lbr_filter(event); 1136 if (ret) 1137 return ret; 1138 1139 /* 1140 * setup HW LBR filter, if any 1141 */ 1142 if (x86_pmu.lbr_sel_map) 1143 ret = intel_pmu_setup_hw_lbr_filter(event); 1144 1145 return ret; 1146 } 1147 1148 /* 1149 * return the type of control flow change at address "from" 1150 * instruction is not necessarily a branch (in case of interrupt). 1151 * 1152 * The branch type returned also includes the priv level of the 1153 * target of the control flow change (X86_BR_USER, X86_BR_KERNEL). 1154 * 1155 * If a branch type is unknown OR the instruction cannot be 1156 * decoded (e.g., text page not present), then X86_BR_NONE is 1157 * returned. 1158 */ 1159 static int branch_type(unsigned long from, unsigned long to, int abort) 1160 { 1161 struct insn insn; 1162 void *addr; 1163 int bytes_read, bytes_left; 1164 int ret = X86_BR_NONE; 1165 int ext, to_plm, from_plm; 1166 u8 buf[MAX_INSN_SIZE]; 1167 int is64 = 0; 1168 1169 to_plm = kernel_ip(to) ? X86_BR_KERNEL : X86_BR_USER; 1170 from_plm = kernel_ip(from) ? X86_BR_KERNEL : X86_BR_USER; 1171 1172 /* 1173 * maybe zero if lbr did not fill up after a reset by the time 1174 * we get a PMU interrupt 1175 */ 1176 if (from == 0 || to == 0) 1177 return X86_BR_NONE; 1178 1179 if (abort) 1180 return X86_BR_ABORT | to_plm; 1181 1182 if (from_plm == X86_BR_USER) { 1183 /* 1184 * can happen if measuring at the user level only 1185 * and we interrupt in a kernel thread, e.g., idle. 1186 */ 1187 if (!current->mm) 1188 return X86_BR_NONE; 1189 1190 /* may fail if text not present */ 1191 bytes_left = copy_from_user_nmi(buf, (void __user *)from, 1192 MAX_INSN_SIZE); 1193 bytes_read = MAX_INSN_SIZE - bytes_left; 1194 if (!bytes_read) 1195 return X86_BR_NONE; 1196 1197 addr = buf; 1198 } else { 1199 /* 1200 * The LBR logs any address in the IP, even if the IP just 1201 * faulted. This means userspace can control the from address. 1202 * Ensure we don't blindly read any address by validating it is 1203 * a known text address. 1204 */ 1205 if (kernel_text_address(from)) { 1206 addr = (void *)from; 1207 /* 1208 * Assume we can get the maximum possible size 1209 * when grabbing kernel data. This is not 1210 * _strictly_ true since we could possibly be 1211 * executing up next to a memory hole, but 1212 * it is very unlikely to be a problem. 1213 */ 1214 bytes_read = MAX_INSN_SIZE; 1215 } else { 1216 return X86_BR_NONE; 1217 } 1218 } 1219 1220 /* 1221 * decoder needs to know the ABI especially 1222 * on 64-bit systems running 32-bit apps 1223 */ 1224 #ifdef CONFIG_X86_64 1225 is64 = kernel_ip((unsigned long)addr) || any_64bit_mode(current_pt_regs()); 1226 #endif 1227 insn_init(&insn, addr, bytes_read, is64); 1228 if (insn_get_opcode(&insn)) 1229 return X86_BR_ABORT; 1230 1231 switch (insn.opcode.bytes[0]) { 1232 case 0xf: 1233 switch (insn.opcode.bytes[1]) { 1234 case 0x05: /* syscall */ 1235 case 0x34: /* sysenter */ 1236 ret = X86_BR_SYSCALL; 1237 break; 1238 case 0x07: /* sysret */ 1239 case 0x35: /* sysexit */ 1240 ret = X86_BR_SYSRET; 1241 break; 1242 case 0x80 ... 0x8f: /* conditional */ 1243 ret = X86_BR_JCC; 1244 break; 1245 default: 1246 ret = X86_BR_NONE; 1247 } 1248 break; 1249 case 0x70 ... 0x7f: /* conditional */ 1250 ret = X86_BR_JCC; 1251 break; 1252 case 0xc2: /* near ret */ 1253 case 0xc3: /* near ret */ 1254 case 0xca: /* far ret */ 1255 case 0xcb: /* far ret */ 1256 ret = X86_BR_RET; 1257 break; 1258 case 0xcf: /* iret */ 1259 ret = X86_BR_IRET; 1260 break; 1261 case 0xcc ... 0xce: /* int */ 1262 ret = X86_BR_INT; 1263 break; 1264 case 0xe8: /* call near rel */ 1265 if (insn_get_immediate(&insn) || insn.immediate1.value == 0) { 1266 /* zero length call */ 1267 ret = X86_BR_ZERO_CALL; 1268 break; 1269 } 1270 fallthrough; 1271 case 0x9a: /* call far absolute */ 1272 ret = X86_BR_CALL; 1273 break; 1274 case 0xe0 ... 0xe3: /* loop jmp */ 1275 ret = X86_BR_JCC; 1276 break; 1277 case 0xe9 ... 0xeb: /* jmp */ 1278 ret = X86_BR_JMP; 1279 break; 1280 case 0xff: /* call near absolute, call far absolute ind */ 1281 if (insn_get_modrm(&insn)) 1282 return X86_BR_ABORT; 1283 1284 ext = (insn.modrm.bytes[0] >> 3) & 0x7; 1285 switch (ext) { 1286 case 2: /* near ind call */ 1287 case 3: /* far ind call */ 1288 ret = X86_BR_IND_CALL; 1289 break; 1290 case 4: 1291 case 5: 1292 ret = X86_BR_IND_JMP; 1293 break; 1294 } 1295 break; 1296 default: 1297 ret = X86_BR_NONE; 1298 } 1299 /* 1300 * interrupts, traps, faults (and thus ring transition) may 1301 * occur on any instructions. Thus, to classify them correctly, 1302 * we need to first look at the from and to priv levels. If they 1303 * are different and to is in the kernel, then it indicates 1304 * a ring transition. If the from instruction is not a ring 1305 * transition instr (syscall, systenter, int), then it means 1306 * it was a irq, trap or fault. 1307 * 1308 * we have no way of detecting kernel to kernel faults. 1309 */ 1310 if (from_plm == X86_BR_USER && to_plm == X86_BR_KERNEL 1311 && ret != X86_BR_SYSCALL && ret != X86_BR_INT) 1312 ret = X86_BR_IRQ; 1313 1314 /* 1315 * branch priv level determined by target as 1316 * is done by HW when LBR_SELECT is implemented 1317 */ 1318 if (ret != X86_BR_NONE) 1319 ret |= to_plm; 1320 1321 return ret; 1322 } 1323 1324 #define X86_BR_TYPE_MAP_MAX 16 1325 1326 static int branch_map[X86_BR_TYPE_MAP_MAX] = { 1327 PERF_BR_CALL, /* X86_BR_CALL */ 1328 PERF_BR_RET, /* X86_BR_RET */ 1329 PERF_BR_SYSCALL, /* X86_BR_SYSCALL */ 1330 PERF_BR_SYSRET, /* X86_BR_SYSRET */ 1331 PERF_BR_UNKNOWN, /* X86_BR_INT */ 1332 PERF_BR_ERET, /* X86_BR_IRET */ 1333 PERF_BR_COND, /* X86_BR_JCC */ 1334 PERF_BR_UNCOND, /* X86_BR_JMP */ 1335 PERF_BR_IRQ, /* X86_BR_IRQ */ 1336 PERF_BR_IND_CALL, /* X86_BR_IND_CALL */ 1337 PERF_BR_UNKNOWN, /* X86_BR_ABORT */ 1338 PERF_BR_UNKNOWN, /* X86_BR_IN_TX */ 1339 PERF_BR_UNKNOWN, /* X86_BR_NO_TX */ 1340 PERF_BR_CALL, /* X86_BR_ZERO_CALL */ 1341 PERF_BR_UNKNOWN, /* X86_BR_CALL_STACK */ 1342 PERF_BR_IND, /* X86_BR_IND_JMP */ 1343 }; 1344 1345 static int 1346 common_branch_type(int type) 1347 { 1348 int i; 1349 1350 type >>= 2; /* skip X86_BR_USER and X86_BR_KERNEL */ 1351 1352 if (type) { 1353 i = __ffs(type); 1354 if (i < X86_BR_TYPE_MAP_MAX) 1355 return branch_map[i]; 1356 } 1357 1358 return PERF_BR_UNKNOWN; 1359 } 1360 1361 enum { 1362 ARCH_LBR_BR_TYPE_JCC = 0, 1363 ARCH_LBR_BR_TYPE_NEAR_IND_JMP = 1, 1364 ARCH_LBR_BR_TYPE_NEAR_REL_JMP = 2, 1365 ARCH_LBR_BR_TYPE_NEAR_IND_CALL = 3, 1366 ARCH_LBR_BR_TYPE_NEAR_REL_CALL = 4, 1367 ARCH_LBR_BR_TYPE_NEAR_RET = 5, 1368 ARCH_LBR_BR_TYPE_KNOWN_MAX = ARCH_LBR_BR_TYPE_NEAR_RET, 1369 1370 ARCH_LBR_BR_TYPE_MAP_MAX = 16, 1371 }; 1372 1373 static const int arch_lbr_br_type_map[ARCH_LBR_BR_TYPE_MAP_MAX] = { 1374 [ARCH_LBR_BR_TYPE_JCC] = X86_BR_JCC, 1375 [ARCH_LBR_BR_TYPE_NEAR_IND_JMP] = X86_BR_IND_JMP, 1376 [ARCH_LBR_BR_TYPE_NEAR_REL_JMP] = X86_BR_JMP, 1377 [ARCH_LBR_BR_TYPE_NEAR_IND_CALL] = X86_BR_IND_CALL, 1378 [ARCH_LBR_BR_TYPE_NEAR_REL_CALL] = X86_BR_CALL, 1379 [ARCH_LBR_BR_TYPE_NEAR_RET] = X86_BR_RET, 1380 }; 1381 1382 /* 1383 * implement actual branch filter based on user demand. 1384 * Hardware may not exactly satisfy that request, thus 1385 * we need to inspect opcodes. Mismatched branches are 1386 * discarded. Therefore, the number of branches returned 1387 * in PERF_SAMPLE_BRANCH_STACK sample may vary. 1388 */ 1389 static void 1390 intel_pmu_lbr_filter(struct cpu_hw_events *cpuc) 1391 { 1392 u64 from, to; 1393 int br_sel = cpuc->br_sel; 1394 int i, j, type, to_plm; 1395 bool compress = false; 1396 1397 /* if sampling all branches, then nothing to filter */ 1398 if (((br_sel & X86_BR_ALL) == X86_BR_ALL) && 1399 ((br_sel & X86_BR_TYPE_SAVE) != X86_BR_TYPE_SAVE)) 1400 return; 1401 1402 for (i = 0; i < cpuc->lbr_stack.nr; i++) { 1403 1404 from = cpuc->lbr_entries[i].from; 1405 to = cpuc->lbr_entries[i].to; 1406 type = cpuc->lbr_entries[i].type; 1407 1408 /* 1409 * Parse the branch type recorded in LBR_x_INFO MSR. 1410 * Doesn't support OTHER_BRANCH decoding for now. 1411 * OTHER_BRANCH branch type still rely on software decoding. 1412 */ 1413 if (static_cpu_has(X86_FEATURE_ARCH_LBR) && 1414 type <= ARCH_LBR_BR_TYPE_KNOWN_MAX) { 1415 to_plm = kernel_ip(to) ? X86_BR_KERNEL : X86_BR_USER; 1416 type = arch_lbr_br_type_map[type] | to_plm; 1417 } else 1418 type = branch_type(from, to, cpuc->lbr_entries[i].abort); 1419 if (type != X86_BR_NONE && (br_sel & X86_BR_ANYTX)) { 1420 if (cpuc->lbr_entries[i].in_tx) 1421 type |= X86_BR_IN_TX; 1422 else 1423 type |= X86_BR_NO_TX; 1424 } 1425 1426 /* if type does not correspond, then discard */ 1427 if (type == X86_BR_NONE || (br_sel & type) != type) { 1428 cpuc->lbr_entries[i].from = 0; 1429 compress = true; 1430 } 1431 1432 if ((br_sel & X86_BR_TYPE_SAVE) == X86_BR_TYPE_SAVE) 1433 cpuc->lbr_entries[i].type = common_branch_type(type); 1434 } 1435 1436 if (!compress) 1437 return; 1438 1439 /* remove all entries with from=0 */ 1440 for (i = 0; i < cpuc->lbr_stack.nr; ) { 1441 if (!cpuc->lbr_entries[i].from) { 1442 j = i; 1443 while (++j < cpuc->lbr_stack.nr) 1444 cpuc->lbr_entries[j-1] = cpuc->lbr_entries[j]; 1445 cpuc->lbr_stack.nr--; 1446 if (!cpuc->lbr_entries[i].from) 1447 continue; 1448 } 1449 i++; 1450 } 1451 } 1452 1453 void intel_pmu_store_pebs_lbrs(struct lbr_entry *lbr) 1454 { 1455 struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); 1456 1457 /* Cannot get TOS for large PEBS and Arch LBR */ 1458 if (static_cpu_has(X86_FEATURE_ARCH_LBR) || 1459 (cpuc->n_pebs == cpuc->n_large_pebs)) 1460 cpuc->lbr_stack.hw_idx = -1ULL; 1461 else 1462 cpuc->lbr_stack.hw_idx = intel_pmu_lbr_tos(); 1463 1464 intel_pmu_store_lbr(cpuc, lbr); 1465 intel_pmu_lbr_filter(cpuc); 1466 } 1467 1468 /* 1469 * Map interface branch filters onto LBR filters 1470 */ 1471 static const int nhm_lbr_sel_map[PERF_SAMPLE_BRANCH_MAX_SHIFT] = { 1472 [PERF_SAMPLE_BRANCH_ANY_SHIFT] = LBR_ANY, 1473 [PERF_SAMPLE_BRANCH_USER_SHIFT] = LBR_USER, 1474 [PERF_SAMPLE_BRANCH_KERNEL_SHIFT] = LBR_KERNEL, 1475 [PERF_SAMPLE_BRANCH_HV_SHIFT] = LBR_IGN, 1476 [PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT] = LBR_RETURN | LBR_REL_JMP 1477 | LBR_IND_JMP | LBR_FAR, 1478 /* 1479 * NHM/WSM erratum: must include REL_JMP+IND_JMP to get CALL branches 1480 */ 1481 [PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT] = 1482 LBR_REL_CALL | LBR_IND_CALL | LBR_REL_JMP | LBR_IND_JMP | LBR_FAR, 1483 /* 1484 * NHM/WSM erratum: must include IND_JMP to capture IND_CALL 1485 */ 1486 [PERF_SAMPLE_BRANCH_IND_CALL_SHIFT] = LBR_IND_CALL | LBR_IND_JMP, 1487 [PERF_SAMPLE_BRANCH_COND_SHIFT] = LBR_JCC, 1488 [PERF_SAMPLE_BRANCH_IND_JUMP_SHIFT] = LBR_IND_JMP, 1489 }; 1490 1491 static const int snb_lbr_sel_map[PERF_SAMPLE_BRANCH_MAX_SHIFT] = { 1492 [PERF_SAMPLE_BRANCH_ANY_SHIFT] = LBR_ANY, 1493 [PERF_SAMPLE_BRANCH_USER_SHIFT] = LBR_USER, 1494 [PERF_SAMPLE_BRANCH_KERNEL_SHIFT] = LBR_KERNEL, 1495 [PERF_SAMPLE_BRANCH_HV_SHIFT] = LBR_IGN, 1496 [PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT] = LBR_RETURN | LBR_FAR, 1497 [PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT] = LBR_REL_CALL | LBR_IND_CALL 1498 | LBR_FAR, 1499 [PERF_SAMPLE_BRANCH_IND_CALL_SHIFT] = LBR_IND_CALL, 1500 [PERF_SAMPLE_BRANCH_COND_SHIFT] = LBR_JCC, 1501 [PERF_SAMPLE_BRANCH_IND_JUMP_SHIFT] = LBR_IND_JMP, 1502 [PERF_SAMPLE_BRANCH_CALL_SHIFT] = LBR_REL_CALL, 1503 }; 1504 1505 static const int hsw_lbr_sel_map[PERF_SAMPLE_BRANCH_MAX_SHIFT] = { 1506 [PERF_SAMPLE_BRANCH_ANY_SHIFT] = LBR_ANY, 1507 [PERF_SAMPLE_BRANCH_USER_SHIFT] = LBR_USER, 1508 [PERF_SAMPLE_BRANCH_KERNEL_SHIFT] = LBR_KERNEL, 1509 [PERF_SAMPLE_BRANCH_HV_SHIFT] = LBR_IGN, 1510 [PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT] = LBR_RETURN | LBR_FAR, 1511 [PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT] = LBR_REL_CALL | LBR_IND_CALL 1512 | LBR_FAR, 1513 [PERF_SAMPLE_BRANCH_IND_CALL_SHIFT] = LBR_IND_CALL, 1514 [PERF_SAMPLE_BRANCH_COND_SHIFT] = LBR_JCC, 1515 [PERF_SAMPLE_BRANCH_CALL_STACK_SHIFT] = LBR_REL_CALL | LBR_IND_CALL 1516 | LBR_RETURN | LBR_CALL_STACK, 1517 [PERF_SAMPLE_BRANCH_IND_JUMP_SHIFT] = LBR_IND_JMP, 1518 [PERF_SAMPLE_BRANCH_CALL_SHIFT] = LBR_REL_CALL, 1519 }; 1520 1521 static int arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_MAX_SHIFT] = { 1522 [PERF_SAMPLE_BRANCH_ANY_SHIFT] = ARCH_LBR_ANY, 1523 [PERF_SAMPLE_BRANCH_USER_SHIFT] = ARCH_LBR_USER, 1524 [PERF_SAMPLE_BRANCH_KERNEL_SHIFT] = ARCH_LBR_KERNEL, 1525 [PERF_SAMPLE_BRANCH_HV_SHIFT] = LBR_IGN, 1526 [PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT] = ARCH_LBR_RETURN | 1527 ARCH_LBR_OTHER_BRANCH, 1528 [PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT] = ARCH_LBR_REL_CALL | 1529 ARCH_LBR_IND_CALL | 1530 ARCH_LBR_OTHER_BRANCH, 1531 [PERF_SAMPLE_BRANCH_IND_CALL_SHIFT] = ARCH_LBR_IND_CALL, 1532 [PERF_SAMPLE_BRANCH_COND_SHIFT] = ARCH_LBR_JCC, 1533 [PERF_SAMPLE_BRANCH_CALL_STACK_SHIFT] = ARCH_LBR_REL_CALL | 1534 ARCH_LBR_IND_CALL | 1535 ARCH_LBR_RETURN | 1536 ARCH_LBR_CALL_STACK, 1537 [PERF_SAMPLE_BRANCH_IND_JUMP_SHIFT] = ARCH_LBR_IND_JMP, 1538 [PERF_SAMPLE_BRANCH_CALL_SHIFT] = ARCH_LBR_REL_CALL, 1539 }; 1540 1541 /* core */ 1542 void __init intel_pmu_lbr_init_core(void) 1543 { 1544 x86_pmu.lbr_nr = 4; 1545 x86_pmu.lbr_tos = MSR_LBR_TOS; 1546 x86_pmu.lbr_from = MSR_LBR_CORE_FROM; 1547 x86_pmu.lbr_to = MSR_LBR_CORE_TO; 1548 1549 /* 1550 * SW branch filter usage: 1551 * - compensate for lack of HW filter 1552 */ 1553 } 1554 1555 /* nehalem/westmere */ 1556 void __init intel_pmu_lbr_init_nhm(void) 1557 { 1558 x86_pmu.lbr_nr = 16; 1559 x86_pmu.lbr_tos = MSR_LBR_TOS; 1560 x86_pmu.lbr_from = MSR_LBR_NHM_FROM; 1561 x86_pmu.lbr_to = MSR_LBR_NHM_TO; 1562 1563 x86_pmu.lbr_sel_mask = LBR_SEL_MASK; 1564 x86_pmu.lbr_sel_map = nhm_lbr_sel_map; 1565 1566 /* 1567 * SW branch filter usage: 1568 * - workaround LBR_SEL errata (see above) 1569 * - support syscall, sysret capture. 1570 * That requires LBR_FAR but that means far 1571 * jmp need to be filtered out 1572 */ 1573 } 1574 1575 /* sandy bridge */ 1576 void __init intel_pmu_lbr_init_snb(void) 1577 { 1578 x86_pmu.lbr_nr = 16; 1579 x86_pmu.lbr_tos = MSR_LBR_TOS; 1580 x86_pmu.lbr_from = MSR_LBR_NHM_FROM; 1581 x86_pmu.lbr_to = MSR_LBR_NHM_TO; 1582 1583 x86_pmu.lbr_sel_mask = LBR_SEL_MASK; 1584 x86_pmu.lbr_sel_map = snb_lbr_sel_map; 1585 1586 /* 1587 * SW branch filter usage: 1588 * - support syscall, sysret capture. 1589 * That requires LBR_FAR but that means far 1590 * jmp need to be filtered out 1591 */ 1592 } 1593 1594 static inline struct kmem_cache * 1595 create_lbr_kmem_cache(size_t size, size_t align) 1596 { 1597 return kmem_cache_create("x86_lbr", size, align, 0, NULL); 1598 } 1599 1600 /* haswell */ 1601 void intel_pmu_lbr_init_hsw(void) 1602 { 1603 size_t size = sizeof(struct x86_perf_task_context); 1604 1605 x86_pmu.lbr_nr = 16; 1606 x86_pmu.lbr_tos = MSR_LBR_TOS; 1607 x86_pmu.lbr_from = MSR_LBR_NHM_FROM; 1608 x86_pmu.lbr_to = MSR_LBR_NHM_TO; 1609 1610 x86_pmu.lbr_sel_mask = LBR_SEL_MASK; 1611 x86_pmu.lbr_sel_map = hsw_lbr_sel_map; 1612 1613 x86_get_pmu(smp_processor_id())->task_ctx_cache = create_lbr_kmem_cache(size, 0); 1614 1615 if (lbr_from_signext_quirk_needed()) 1616 static_branch_enable(&lbr_from_quirk_key); 1617 } 1618 1619 /* skylake */ 1620 __init void intel_pmu_lbr_init_skl(void) 1621 { 1622 size_t size = sizeof(struct x86_perf_task_context); 1623 1624 x86_pmu.lbr_nr = 32; 1625 x86_pmu.lbr_tos = MSR_LBR_TOS; 1626 x86_pmu.lbr_from = MSR_LBR_NHM_FROM; 1627 x86_pmu.lbr_to = MSR_LBR_NHM_TO; 1628 x86_pmu.lbr_info = MSR_LBR_INFO_0; 1629 1630 x86_pmu.lbr_sel_mask = LBR_SEL_MASK; 1631 x86_pmu.lbr_sel_map = hsw_lbr_sel_map; 1632 1633 x86_get_pmu(smp_processor_id())->task_ctx_cache = create_lbr_kmem_cache(size, 0); 1634 1635 /* 1636 * SW branch filter usage: 1637 * - support syscall, sysret capture. 1638 * That requires LBR_FAR but that means far 1639 * jmp need to be filtered out 1640 */ 1641 } 1642 1643 /* atom */ 1644 void __init intel_pmu_lbr_init_atom(void) 1645 { 1646 /* 1647 * only models starting at stepping 10 seems 1648 * to have an operational LBR which can freeze 1649 * on PMU interrupt 1650 */ 1651 if (boot_cpu_data.x86_model == 28 1652 && boot_cpu_data.x86_stepping < 10) { 1653 pr_cont("LBR disabled due to erratum"); 1654 return; 1655 } 1656 1657 x86_pmu.lbr_nr = 8; 1658 x86_pmu.lbr_tos = MSR_LBR_TOS; 1659 x86_pmu.lbr_from = MSR_LBR_CORE_FROM; 1660 x86_pmu.lbr_to = MSR_LBR_CORE_TO; 1661 1662 /* 1663 * SW branch filter usage: 1664 * - compensate for lack of HW filter 1665 */ 1666 } 1667 1668 /* slm */ 1669 void __init intel_pmu_lbr_init_slm(void) 1670 { 1671 x86_pmu.lbr_nr = 8; 1672 x86_pmu.lbr_tos = MSR_LBR_TOS; 1673 x86_pmu.lbr_from = MSR_LBR_CORE_FROM; 1674 x86_pmu.lbr_to = MSR_LBR_CORE_TO; 1675 1676 x86_pmu.lbr_sel_mask = LBR_SEL_MASK; 1677 x86_pmu.lbr_sel_map = nhm_lbr_sel_map; 1678 1679 /* 1680 * SW branch filter usage: 1681 * - compensate for lack of HW filter 1682 */ 1683 pr_cont("8-deep LBR, "); 1684 } 1685 1686 /* Knights Landing */ 1687 void intel_pmu_lbr_init_knl(void) 1688 { 1689 x86_pmu.lbr_nr = 8; 1690 x86_pmu.lbr_tos = MSR_LBR_TOS; 1691 x86_pmu.lbr_from = MSR_LBR_NHM_FROM; 1692 x86_pmu.lbr_to = MSR_LBR_NHM_TO; 1693 1694 x86_pmu.lbr_sel_mask = LBR_SEL_MASK; 1695 x86_pmu.lbr_sel_map = snb_lbr_sel_map; 1696 1697 /* Knights Landing does have MISPREDICT bit */ 1698 if (x86_pmu.intel_cap.lbr_format == LBR_FORMAT_LIP) 1699 x86_pmu.intel_cap.lbr_format = LBR_FORMAT_EIP_FLAGS; 1700 } 1701 1702 void intel_pmu_lbr_init(void) 1703 { 1704 switch (x86_pmu.intel_cap.lbr_format) { 1705 case LBR_FORMAT_EIP_FLAGS2: 1706 x86_pmu.lbr_has_tsx = 1; 1707 fallthrough; 1708 case LBR_FORMAT_EIP_FLAGS: 1709 x86_pmu.lbr_from_flags = 1; 1710 break; 1711 1712 case LBR_FORMAT_INFO: 1713 x86_pmu.lbr_has_tsx = 1; 1714 fallthrough; 1715 case LBR_FORMAT_INFO2: 1716 x86_pmu.lbr_has_info = 1; 1717 break; 1718 1719 case LBR_FORMAT_TIME: 1720 x86_pmu.lbr_from_flags = 1; 1721 x86_pmu.lbr_to_cycles = 1; 1722 break; 1723 } 1724 1725 if (x86_pmu.lbr_has_info) { 1726 /* 1727 * Only used in combination with baseline pebs. 1728 */ 1729 static_branch_enable(&x86_lbr_mispred); 1730 static_branch_enable(&x86_lbr_cycles); 1731 } 1732 } 1733 1734 /* 1735 * LBR state size is variable based on the max number of registers. 1736 * This calculates the expected state size, which should match 1737 * what the hardware enumerates for the size of XFEATURE_LBR. 1738 */ 1739 static inline unsigned int get_lbr_state_size(void) 1740 { 1741 return sizeof(struct arch_lbr_state) + 1742 x86_pmu.lbr_nr * sizeof(struct lbr_entry); 1743 } 1744 1745 static bool is_arch_lbr_xsave_available(void) 1746 { 1747 if (!boot_cpu_has(X86_FEATURE_XSAVES)) 1748 return false; 1749 1750 /* 1751 * Check the LBR state with the corresponding software structure. 1752 * Disable LBR XSAVES support if the size doesn't match. 1753 */ 1754 if (xfeature_size(XFEATURE_LBR) == 0) 1755 return false; 1756 1757 if (WARN_ON(xfeature_size(XFEATURE_LBR) != get_lbr_state_size())) 1758 return false; 1759 1760 return true; 1761 } 1762 1763 void __init intel_pmu_arch_lbr_init(void) 1764 { 1765 struct pmu *pmu = x86_get_pmu(smp_processor_id()); 1766 union cpuid28_eax eax; 1767 union cpuid28_ebx ebx; 1768 union cpuid28_ecx ecx; 1769 unsigned int unused_edx; 1770 bool arch_lbr_xsave; 1771 size_t size; 1772 u64 lbr_nr; 1773 1774 /* Arch LBR Capabilities */ 1775 cpuid(28, &eax.full, &ebx.full, &ecx.full, &unused_edx); 1776 1777 lbr_nr = fls(eax.split.lbr_depth_mask) * 8; 1778 if (!lbr_nr) 1779 goto clear_arch_lbr; 1780 1781 /* Apply the max depth of Arch LBR */ 1782 if (wrmsrl_safe(MSR_ARCH_LBR_DEPTH, lbr_nr)) 1783 goto clear_arch_lbr; 1784 1785 x86_pmu.lbr_depth_mask = eax.split.lbr_depth_mask; 1786 x86_pmu.lbr_deep_c_reset = eax.split.lbr_deep_c_reset; 1787 x86_pmu.lbr_lip = eax.split.lbr_lip; 1788 x86_pmu.lbr_cpl = ebx.split.lbr_cpl; 1789 x86_pmu.lbr_filter = ebx.split.lbr_filter; 1790 x86_pmu.lbr_call_stack = ebx.split.lbr_call_stack; 1791 x86_pmu.lbr_mispred = ecx.split.lbr_mispred; 1792 x86_pmu.lbr_timed_lbr = ecx.split.lbr_timed_lbr; 1793 x86_pmu.lbr_br_type = ecx.split.lbr_br_type; 1794 x86_pmu.lbr_nr = lbr_nr; 1795 1796 if (x86_pmu.lbr_mispred) 1797 static_branch_enable(&x86_lbr_mispred); 1798 if (x86_pmu.lbr_timed_lbr) 1799 static_branch_enable(&x86_lbr_cycles); 1800 if (x86_pmu.lbr_br_type) 1801 static_branch_enable(&x86_lbr_type); 1802 1803 arch_lbr_xsave = is_arch_lbr_xsave_available(); 1804 if (arch_lbr_xsave) { 1805 size = sizeof(struct x86_perf_task_context_arch_lbr_xsave) + 1806 get_lbr_state_size(); 1807 pmu->task_ctx_cache = create_lbr_kmem_cache(size, 1808 XSAVE_ALIGNMENT); 1809 } 1810 1811 if (!pmu->task_ctx_cache) { 1812 arch_lbr_xsave = false; 1813 1814 size = sizeof(struct x86_perf_task_context_arch_lbr) + 1815 lbr_nr * sizeof(struct lbr_entry); 1816 pmu->task_ctx_cache = create_lbr_kmem_cache(size, 0); 1817 } 1818 1819 x86_pmu.lbr_from = MSR_ARCH_LBR_FROM_0; 1820 x86_pmu.lbr_to = MSR_ARCH_LBR_TO_0; 1821 x86_pmu.lbr_info = MSR_ARCH_LBR_INFO_0; 1822 1823 /* LBR callstack requires both CPL and Branch Filtering support */ 1824 if (!x86_pmu.lbr_cpl || 1825 !x86_pmu.lbr_filter || 1826 !x86_pmu.lbr_call_stack) 1827 arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_CALL_STACK_SHIFT] = LBR_NOT_SUPP; 1828 1829 if (!x86_pmu.lbr_cpl) { 1830 arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_USER_SHIFT] = LBR_NOT_SUPP; 1831 arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_KERNEL_SHIFT] = LBR_NOT_SUPP; 1832 } else if (!x86_pmu.lbr_filter) { 1833 arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_ANY_SHIFT] = LBR_NOT_SUPP; 1834 arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT] = LBR_NOT_SUPP; 1835 arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT] = LBR_NOT_SUPP; 1836 arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_IND_CALL_SHIFT] = LBR_NOT_SUPP; 1837 arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_COND_SHIFT] = LBR_NOT_SUPP; 1838 arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_IND_JUMP_SHIFT] = LBR_NOT_SUPP; 1839 arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_CALL_SHIFT] = LBR_NOT_SUPP; 1840 } 1841 1842 x86_pmu.lbr_ctl_mask = ARCH_LBR_CTL_MASK; 1843 x86_pmu.lbr_ctl_map = arch_lbr_ctl_map; 1844 1845 if (!x86_pmu.lbr_cpl && !x86_pmu.lbr_filter) 1846 x86_pmu.lbr_ctl_map = NULL; 1847 1848 x86_pmu.lbr_reset = intel_pmu_arch_lbr_reset; 1849 if (arch_lbr_xsave) { 1850 x86_pmu.lbr_save = intel_pmu_arch_lbr_xsaves; 1851 x86_pmu.lbr_restore = intel_pmu_arch_lbr_xrstors; 1852 x86_pmu.lbr_read = intel_pmu_arch_lbr_read_xsave; 1853 pr_cont("XSAVE "); 1854 } else { 1855 x86_pmu.lbr_save = intel_pmu_arch_lbr_save; 1856 x86_pmu.lbr_restore = intel_pmu_arch_lbr_restore; 1857 x86_pmu.lbr_read = intel_pmu_arch_lbr_read; 1858 } 1859 1860 pr_cont("Architectural LBR, "); 1861 1862 return; 1863 1864 clear_arch_lbr: 1865 clear_cpu_cap(&boot_cpu_data, X86_FEATURE_ARCH_LBR); 1866 } 1867 1868 /** 1869 * x86_perf_get_lbr - get the LBR records information 1870 * 1871 * @lbr: the caller's memory to store the LBR records information 1872 * 1873 * Returns: 0 indicates the LBR info has been successfully obtained 1874 */ 1875 int x86_perf_get_lbr(struct x86_pmu_lbr *lbr) 1876 { 1877 int lbr_fmt = x86_pmu.intel_cap.lbr_format; 1878 1879 lbr->nr = x86_pmu.lbr_nr; 1880 lbr->from = x86_pmu.lbr_from; 1881 lbr->to = x86_pmu.lbr_to; 1882 lbr->info = (lbr_fmt == LBR_FORMAT_INFO) ? x86_pmu.lbr_info : 0; 1883 1884 return 0; 1885 } 1886 EXPORT_SYMBOL_GPL(x86_perf_get_lbr); 1887 1888 struct event_constraint vlbr_constraint = 1889 __EVENT_CONSTRAINT(INTEL_FIXED_VLBR_EVENT, (1ULL << INTEL_PMC_IDX_FIXED_VLBR), 1890 FIXED_EVENT_FLAGS, 1, 0, PERF_X86_EVENT_LBR_SELECT); 1891