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 format LBR_FORMAT_EIP_FLAGS2, bits 61:62 in MSR_LAST_BRANCH_FROM_x 282 * are the TSX flags when TSX is supported, but when TSX is not supported 283 * 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 format LBR_FORMAT_EIP_FLAGS2 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; 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 struct perf_branch_entry *br = cpuc->lbr_entries; 773 u64 tos = intel_pmu_lbr_tos(); 774 int i; 775 776 for (i = 0; i < x86_pmu.lbr_nr; i++) { 777 unsigned long lbr_idx = (tos - i) & mask; 778 union { 779 struct { 780 u32 from; 781 u32 to; 782 }; 783 u64 lbr; 784 } msr_lastbranch; 785 786 rdmsrl(x86_pmu.lbr_from + lbr_idx, msr_lastbranch.lbr); 787 788 perf_clear_branch_entry_bitfields(br); 789 790 br->from = msr_lastbranch.from; 791 br->to = msr_lastbranch.to; 792 br++; 793 } 794 cpuc->lbr_stack.nr = i; 795 cpuc->lbr_stack.hw_idx = tos; 796 } 797 798 /* 799 * Due to lack of segmentation in Linux the effective address (offset) 800 * is the same as the linear address, allowing us to merge the LIP and EIP 801 * LBR formats. 802 */ 803 void intel_pmu_lbr_read_64(struct cpu_hw_events *cpuc) 804 { 805 bool need_info = false, call_stack = false; 806 unsigned long mask = x86_pmu.lbr_nr - 1; 807 struct perf_branch_entry *br = cpuc->lbr_entries; 808 u64 tos = intel_pmu_lbr_tos(); 809 int i; 810 int out = 0; 811 int num = x86_pmu.lbr_nr; 812 813 if (cpuc->lbr_sel) { 814 need_info = !(cpuc->lbr_sel->config & LBR_NO_INFO); 815 if (cpuc->lbr_sel->config & LBR_CALL_STACK) 816 call_stack = true; 817 } 818 819 for (i = 0; i < num; i++) { 820 unsigned long lbr_idx = (tos - i) & mask; 821 u64 from, to, mis = 0, pred = 0, in_tx = 0, abort = 0; 822 u16 cycles = 0; 823 824 from = rdlbr_from(lbr_idx, NULL); 825 to = rdlbr_to(lbr_idx, NULL); 826 827 /* 828 * Read LBR call stack entries 829 * until invalid entry (0s) is detected. 830 */ 831 if (call_stack && !from) 832 break; 833 834 if (x86_pmu.lbr_has_info) { 835 if (need_info) { 836 u64 info; 837 838 info = rdlbr_info(lbr_idx, NULL); 839 mis = !!(info & LBR_INFO_MISPRED); 840 pred = !mis; 841 cycles = (info & LBR_INFO_CYCLES); 842 if (x86_pmu.lbr_has_tsx) { 843 in_tx = !!(info & LBR_INFO_IN_TX); 844 abort = !!(info & LBR_INFO_ABORT); 845 } 846 } 847 } else { 848 int skip = 0; 849 850 if (x86_pmu.lbr_from_flags) { 851 mis = !!(from & LBR_FROM_FLAG_MISPRED); 852 pred = !mis; 853 skip = 1; 854 } 855 if (x86_pmu.lbr_has_tsx) { 856 in_tx = !!(from & LBR_FROM_FLAG_IN_TX); 857 abort = !!(from & LBR_FROM_FLAG_ABORT); 858 skip = 3; 859 } 860 from = (u64)((((s64)from) << skip) >> skip); 861 862 if (x86_pmu.lbr_to_cycles) { 863 cycles = ((to >> 48) & LBR_INFO_CYCLES); 864 to = (u64)((((s64)to) << 16) >> 16); 865 } 866 } 867 868 /* 869 * Some CPUs report duplicated abort records, 870 * with the second entry not having an abort bit set. 871 * Skip them here. This loop runs backwards, 872 * so we need to undo the previous record. 873 * If the abort just happened outside the window 874 * the extra entry cannot be removed. 875 */ 876 if (abort && x86_pmu.lbr_double_abort && out > 0) 877 out--; 878 879 perf_clear_branch_entry_bitfields(br+out); 880 br[out].from = from; 881 br[out].to = to; 882 br[out].mispred = mis; 883 br[out].predicted = pred; 884 br[out].in_tx = in_tx; 885 br[out].abort = abort; 886 br[out].cycles = cycles; 887 out++; 888 } 889 cpuc->lbr_stack.nr = out; 890 cpuc->lbr_stack.hw_idx = tos; 891 } 892 893 static DEFINE_STATIC_KEY_FALSE(x86_lbr_mispred); 894 static DEFINE_STATIC_KEY_FALSE(x86_lbr_cycles); 895 static DEFINE_STATIC_KEY_FALSE(x86_lbr_type); 896 897 static __always_inline int get_lbr_br_type(u64 info) 898 { 899 int type = 0; 900 901 if (static_branch_likely(&x86_lbr_type)) 902 type = (info & LBR_INFO_BR_TYPE) >> LBR_INFO_BR_TYPE_OFFSET; 903 904 return type; 905 } 906 907 static __always_inline bool get_lbr_mispred(u64 info) 908 { 909 bool mispred = 0; 910 911 if (static_branch_likely(&x86_lbr_mispred)) 912 mispred = !!(info & LBR_INFO_MISPRED); 913 914 return mispred; 915 } 916 917 static __always_inline u16 get_lbr_cycles(u64 info) 918 { 919 u16 cycles = info & LBR_INFO_CYCLES; 920 921 if (static_cpu_has(X86_FEATURE_ARCH_LBR) && 922 (!static_branch_likely(&x86_lbr_cycles) || 923 !(info & LBR_INFO_CYC_CNT_VALID))) 924 cycles = 0; 925 926 return cycles; 927 } 928 929 static void intel_pmu_store_lbr(struct cpu_hw_events *cpuc, 930 struct lbr_entry *entries) 931 { 932 struct perf_branch_entry *e; 933 struct lbr_entry *lbr; 934 u64 from, to, info; 935 int i; 936 937 for (i = 0; i < x86_pmu.lbr_nr; i++) { 938 lbr = entries ? &entries[i] : NULL; 939 e = &cpuc->lbr_entries[i]; 940 941 from = rdlbr_from(i, lbr); 942 /* 943 * Read LBR entries until invalid entry (0s) is detected. 944 */ 945 if (!from) 946 break; 947 948 to = rdlbr_to(i, lbr); 949 info = rdlbr_info(i, lbr); 950 951 perf_clear_branch_entry_bitfields(e); 952 953 e->from = from; 954 e->to = to; 955 e->mispred = get_lbr_mispred(info); 956 e->predicted = !e->mispred; 957 e->in_tx = !!(info & LBR_INFO_IN_TX); 958 e->abort = !!(info & LBR_INFO_ABORT); 959 e->cycles = get_lbr_cycles(info); 960 e->type = get_lbr_br_type(info); 961 } 962 963 cpuc->lbr_stack.nr = i; 964 } 965 966 static void intel_pmu_arch_lbr_read(struct cpu_hw_events *cpuc) 967 { 968 intel_pmu_store_lbr(cpuc, NULL); 969 } 970 971 static void intel_pmu_arch_lbr_read_xsave(struct cpu_hw_events *cpuc) 972 { 973 struct x86_perf_task_context_arch_lbr_xsave *xsave = cpuc->lbr_xsave; 974 975 if (!xsave) { 976 intel_pmu_store_lbr(cpuc, NULL); 977 return; 978 } 979 xsaves(&xsave->xsave, XFEATURE_MASK_LBR); 980 981 intel_pmu_store_lbr(cpuc, xsave->lbr.entries); 982 } 983 984 void intel_pmu_lbr_read(void) 985 { 986 struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); 987 988 /* 989 * Don't read when all LBRs users are using adaptive PEBS. 990 * 991 * This could be smarter and actually check the event, 992 * but this simple approach seems to work for now. 993 */ 994 if (!cpuc->lbr_users || vlbr_exclude_host() || 995 cpuc->lbr_users == cpuc->lbr_pebs_users) 996 return; 997 998 x86_pmu.lbr_read(cpuc); 999 1000 intel_pmu_lbr_filter(cpuc); 1001 } 1002 1003 /* 1004 * SW filter is used: 1005 * - in case there is no HW filter 1006 * - in case the HW filter has errata or limitations 1007 */ 1008 static int intel_pmu_setup_sw_lbr_filter(struct perf_event *event) 1009 { 1010 u64 br_type = event->attr.branch_sample_type; 1011 int mask = 0; 1012 1013 if (br_type & PERF_SAMPLE_BRANCH_USER) 1014 mask |= X86_BR_USER; 1015 1016 if (br_type & PERF_SAMPLE_BRANCH_KERNEL) 1017 mask |= X86_BR_KERNEL; 1018 1019 /* we ignore BRANCH_HV here */ 1020 1021 if (br_type & PERF_SAMPLE_BRANCH_ANY) 1022 mask |= X86_BR_ANY; 1023 1024 if (br_type & PERF_SAMPLE_BRANCH_ANY_CALL) 1025 mask |= X86_BR_ANY_CALL; 1026 1027 if (br_type & PERF_SAMPLE_BRANCH_ANY_RETURN) 1028 mask |= X86_BR_RET | X86_BR_IRET | X86_BR_SYSRET; 1029 1030 if (br_type & PERF_SAMPLE_BRANCH_IND_CALL) 1031 mask |= X86_BR_IND_CALL; 1032 1033 if (br_type & PERF_SAMPLE_BRANCH_ABORT_TX) 1034 mask |= X86_BR_ABORT; 1035 1036 if (br_type & PERF_SAMPLE_BRANCH_IN_TX) 1037 mask |= X86_BR_IN_TX; 1038 1039 if (br_type & PERF_SAMPLE_BRANCH_NO_TX) 1040 mask |= X86_BR_NO_TX; 1041 1042 if (br_type & PERF_SAMPLE_BRANCH_COND) 1043 mask |= X86_BR_JCC; 1044 1045 if (br_type & PERF_SAMPLE_BRANCH_CALL_STACK) { 1046 if (!x86_pmu_has_lbr_callstack()) 1047 return -EOPNOTSUPP; 1048 if (mask & ~(X86_BR_USER | X86_BR_KERNEL)) 1049 return -EINVAL; 1050 mask |= X86_BR_CALL | X86_BR_IND_CALL | X86_BR_RET | 1051 X86_BR_CALL_STACK; 1052 } 1053 1054 if (br_type & PERF_SAMPLE_BRANCH_IND_JUMP) 1055 mask |= X86_BR_IND_JMP; 1056 1057 if (br_type & PERF_SAMPLE_BRANCH_CALL) 1058 mask |= X86_BR_CALL | X86_BR_ZERO_CALL; 1059 1060 if (br_type & PERF_SAMPLE_BRANCH_TYPE_SAVE) 1061 mask |= X86_BR_TYPE_SAVE; 1062 1063 /* 1064 * stash actual user request into reg, it may 1065 * be used by fixup code for some CPU 1066 */ 1067 event->hw.branch_reg.reg = mask; 1068 return 0; 1069 } 1070 1071 /* 1072 * setup the HW LBR filter 1073 * Used only when available, may not be enough to disambiguate 1074 * all branches, may need the help of the SW filter 1075 */ 1076 static int intel_pmu_setup_hw_lbr_filter(struct perf_event *event) 1077 { 1078 struct hw_perf_event_extra *reg; 1079 u64 br_type = event->attr.branch_sample_type; 1080 u64 mask = 0, v; 1081 int i; 1082 1083 for (i = 0; i < PERF_SAMPLE_BRANCH_MAX_SHIFT; i++) { 1084 if (!(br_type & (1ULL << i))) 1085 continue; 1086 1087 v = x86_pmu.lbr_sel_map[i]; 1088 if (v == LBR_NOT_SUPP) 1089 return -EOPNOTSUPP; 1090 1091 if (v != LBR_IGN) 1092 mask |= v; 1093 } 1094 1095 reg = &event->hw.branch_reg; 1096 reg->idx = EXTRA_REG_LBR; 1097 1098 if (static_cpu_has(X86_FEATURE_ARCH_LBR)) { 1099 reg->config = mask; 1100 return 0; 1101 } 1102 1103 /* 1104 * The first 9 bits (LBR_SEL_MASK) in LBR_SELECT operate 1105 * in suppress mode. So LBR_SELECT should be set to 1106 * (~mask & LBR_SEL_MASK) | (mask & ~LBR_SEL_MASK) 1107 * But the 10th bit LBR_CALL_STACK does not operate 1108 * in suppress mode. 1109 */ 1110 reg->config = mask ^ (x86_pmu.lbr_sel_mask & ~LBR_CALL_STACK); 1111 1112 if ((br_type & PERF_SAMPLE_BRANCH_NO_CYCLES) && 1113 (br_type & PERF_SAMPLE_BRANCH_NO_FLAGS) && 1114 x86_pmu.lbr_has_info) 1115 reg->config |= LBR_NO_INFO; 1116 1117 return 0; 1118 } 1119 1120 int intel_pmu_setup_lbr_filter(struct perf_event *event) 1121 { 1122 int ret = 0; 1123 1124 /* 1125 * no LBR on this PMU 1126 */ 1127 if (!x86_pmu.lbr_nr) 1128 return -EOPNOTSUPP; 1129 1130 /* 1131 * setup SW LBR filter 1132 */ 1133 ret = intel_pmu_setup_sw_lbr_filter(event); 1134 if (ret) 1135 return ret; 1136 1137 /* 1138 * setup HW LBR filter, if any 1139 */ 1140 if (x86_pmu.lbr_sel_map) 1141 ret = intel_pmu_setup_hw_lbr_filter(event); 1142 1143 return ret; 1144 } 1145 1146 /* 1147 * return the type of control flow change at address "from" 1148 * instruction is not necessarily a branch (in case of interrupt). 1149 * 1150 * The branch type returned also includes the priv level of the 1151 * target of the control flow change (X86_BR_USER, X86_BR_KERNEL). 1152 * 1153 * If a branch type is unknown OR the instruction cannot be 1154 * decoded (e.g., text page not present), then X86_BR_NONE is 1155 * returned. 1156 */ 1157 static int branch_type(unsigned long from, unsigned long to, int abort) 1158 { 1159 struct insn insn; 1160 void *addr; 1161 int bytes_read, bytes_left; 1162 int ret = X86_BR_NONE; 1163 int ext, to_plm, from_plm; 1164 u8 buf[MAX_INSN_SIZE]; 1165 int is64 = 0; 1166 1167 to_plm = kernel_ip(to) ? X86_BR_KERNEL : X86_BR_USER; 1168 from_plm = kernel_ip(from) ? X86_BR_KERNEL : X86_BR_USER; 1169 1170 /* 1171 * maybe zero if lbr did not fill up after a reset by the time 1172 * we get a PMU interrupt 1173 */ 1174 if (from == 0 || to == 0) 1175 return X86_BR_NONE; 1176 1177 if (abort) 1178 return X86_BR_ABORT | to_plm; 1179 1180 if (from_plm == X86_BR_USER) { 1181 /* 1182 * can happen if measuring at the user level only 1183 * and we interrupt in a kernel thread, e.g., idle. 1184 */ 1185 if (!current->mm) 1186 return X86_BR_NONE; 1187 1188 /* may fail if text not present */ 1189 bytes_left = copy_from_user_nmi(buf, (void __user *)from, 1190 MAX_INSN_SIZE); 1191 bytes_read = MAX_INSN_SIZE - bytes_left; 1192 if (!bytes_read) 1193 return X86_BR_NONE; 1194 1195 addr = buf; 1196 } else { 1197 /* 1198 * The LBR logs any address in the IP, even if the IP just 1199 * faulted. This means userspace can control the from address. 1200 * Ensure we don't blindly read any address by validating it is 1201 * a known text address. 1202 */ 1203 if (kernel_text_address(from)) { 1204 addr = (void *)from; 1205 /* 1206 * Assume we can get the maximum possible size 1207 * when grabbing kernel data. This is not 1208 * _strictly_ true since we could possibly be 1209 * executing up next to a memory hole, but 1210 * it is very unlikely to be a problem. 1211 */ 1212 bytes_read = MAX_INSN_SIZE; 1213 } else { 1214 return X86_BR_NONE; 1215 } 1216 } 1217 1218 /* 1219 * decoder needs to know the ABI especially 1220 * on 64-bit systems running 32-bit apps 1221 */ 1222 #ifdef CONFIG_X86_64 1223 is64 = kernel_ip((unsigned long)addr) || any_64bit_mode(current_pt_regs()); 1224 #endif 1225 insn_init(&insn, addr, bytes_read, is64); 1226 if (insn_get_opcode(&insn)) 1227 return X86_BR_ABORT; 1228 1229 switch (insn.opcode.bytes[0]) { 1230 case 0xf: 1231 switch (insn.opcode.bytes[1]) { 1232 case 0x05: /* syscall */ 1233 case 0x34: /* sysenter */ 1234 ret = X86_BR_SYSCALL; 1235 break; 1236 case 0x07: /* sysret */ 1237 case 0x35: /* sysexit */ 1238 ret = X86_BR_SYSRET; 1239 break; 1240 case 0x80 ... 0x8f: /* conditional */ 1241 ret = X86_BR_JCC; 1242 break; 1243 default: 1244 ret = X86_BR_NONE; 1245 } 1246 break; 1247 case 0x70 ... 0x7f: /* conditional */ 1248 ret = X86_BR_JCC; 1249 break; 1250 case 0xc2: /* near ret */ 1251 case 0xc3: /* near ret */ 1252 case 0xca: /* far ret */ 1253 case 0xcb: /* far ret */ 1254 ret = X86_BR_RET; 1255 break; 1256 case 0xcf: /* iret */ 1257 ret = X86_BR_IRET; 1258 break; 1259 case 0xcc ... 0xce: /* int */ 1260 ret = X86_BR_INT; 1261 break; 1262 case 0xe8: /* call near rel */ 1263 if (insn_get_immediate(&insn) || insn.immediate1.value == 0) { 1264 /* zero length call */ 1265 ret = X86_BR_ZERO_CALL; 1266 break; 1267 } 1268 fallthrough; 1269 case 0x9a: /* call far absolute */ 1270 ret = X86_BR_CALL; 1271 break; 1272 case 0xe0 ... 0xe3: /* loop jmp */ 1273 ret = X86_BR_JCC; 1274 break; 1275 case 0xe9 ... 0xeb: /* jmp */ 1276 ret = X86_BR_JMP; 1277 break; 1278 case 0xff: /* call near absolute, call far absolute ind */ 1279 if (insn_get_modrm(&insn)) 1280 return X86_BR_ABORT; 1281 1282 ext = (insn.modrm.bytes[0] >> 3) & 0x7; 1283 switch (ext) { 1284 case 2: /* near ind call */ 1285 case 3: /* far ind call */ 1286 ret = X86_BR_IND_CALL; 1287 break; 1288 case 4: 1289 case 5: 1290 ret = X86_BR_IND_JMP; 1291 break; 1292 } 1293 break; 1294 default: 1295 ret = X86_BR_NONE; 1296 } 1297 /* 1298 * interrupts, traps, faults (and thus ring transition) may 1299 * occur on any instructions. Thus, to classify them correctly, 1300 * we need to first look at the from and to priv levels. If they 1301 * are different and to is in the kernel, then it indicates 1302 * a ring transition. If the from instruction is not a ring 1303 * transition instr (syscall, systenter, int), then it means 1304 * it was a irq, trap or fault. 1305 * 1306 * we have no way of detecting kernel to kernel faults. 1307 */ 1308 if (from_plm == X86_BR_USER && to_plm == X86_BR_KERNEL 1309 && ret != X86_BR_SYSCALL && ret != X86_BR_INT) 1310 ret = X86_BR_IRQ; 1311 1312 /* 1313 * branch priv level determined by target as 1314 * is done by HW when LBR_SELECT is implemented 1315 */ 1316 if (ret != X86_BR_NONE) 1317 ret |= to_plm; 1318 1319 return ret; 1320 } 1321 1322 #define X86_BR_TYPE_MAP_MAX 16 1323 1324 static int branch_map[X86_BR_TYPE_MAP_MAX] = { 1325 PERF_BR_CALL, /* X86_BR_CALL */ 1326 PERF_BR_RET, /* X86_BR_RET */ 1327 PERF_BR_SYSCALL, /* X86_BR_SYSCALL */ 1328 PERF_BR_SYSRET, /* X86_BR_SYSRET */ 1329 PERF_BR_UNKNOWN, /* X86_BR_INT */ 1330 PERF_BR_ERET, /* X86_BR_IRET */ 1331 PERF_BR_COND, /* X86_BR_JCC */ 1332 PERF_BR_UNCOND, /* X86_BR_JMP */ 1333 PERF_BR_IRQ, /* X86_BR_IRQ */ 1334 PERF_BR_IND_CALL, /* X86_BR_IND_CALL */ 1335 PERF_BR_UNKNOWN, /* X86_BR_ABORT */ 1336 PERF_BR_UNKNOWN, /* X86_BR_IN_TX */ 1337 PERF_BR_UNKNOWN, /* X86_BR_NO_TX */ 1338 PERF_BR_CALL, /* X86_BR_ZERO_CALL */ 1339 PERF_BR_UNKNOWN, /* X86_BR_CALL_STACK */ 1340 PERF_BR_IND, /* X86_BR_IND_JMP */ 1341 }; 1342 1343 static int 1344 common_branch_type(int type) 1345 { 1346 int i; 1347 1348 type >>= 2; /* skip X86_BR_USER and X86_BR_KERNEL */ 1349 1350 if (type) { 1351 i = __ffs(type); 1352 if (i < X86_BR_TYPE_MAP_MAX) 1353 return branch_map[i]; 1354 } 1355 1356 return PERF_BR_UNKNOWN; 1357 } 1358 1359 enum { 1360 ARCH_LBR_BR_TYPE_JCC = 0, 1361 ARCH_LBR_BR_TYPE_NEAR_IND_JMP = 1, 1362 ARCH_LBR_BR_TYPE_NEAR_REL_JMP = 2, 1363 ARCH_LBR_BR_TYPE_NEAR_IND_CALL = 3, 1364 ARCH_LBR_BR_TYPE_NEAR_REL_CALL = 4, 1365 ARCH_LBR_BR_TYPE_NEAR_RET = 5, 1366 ARCH_LBR_BR_TYPE_KNOWN_MAX = ARCH_LBR_BR_TYPE_NEAR_RET, 1367 1368 ARCH_LBR_BR_TYPE_MAP_MAX = 16, 1369 }; 1370 1371 static const int arch_lbr_br_type_map[ARCH_LBR_BR_TYPE_MAP_MAX] = { 1372 [ARCH_LBR_BR_TYPE_JCC] = X86_BR_JCC, 1373 [ARCH_LBR_BR_TYPE_NEAR_IND_JMP] = X86_BR_IND_JMP, 1374 [ARCH_LBR_BR_TYPE_NEAR_REL_JMP] = X86_BR_JMP, 1375 [ARCH_LBR_BR_TYPE_NEAR_IND_CALL] = X86_BR_IND_CALL, 1376 [ARCH_LBR_BR_TYPE_NEAR_REL_CALL] = X86_BR_CALL, 1377 [ARCH_LBR_BR_TYPE_NEAR_RET] = X86_BR_RET, 1378 }; 1379 1380 /* 1381 * implement actual branch filter based on user demand. 1382 * Hardware may not exactly satisfy that request, thus 1383 * we need to inspect opcodes. Mismatched branches are 1384 * discarded. Therefore, the number of branches returned 1385 * in PERF_SAMPLE_BRANCH_STACK sample may vary. 1386 */ 1387 static void 1388 intel_pmu_lbr_filter(struct cpu_hw_events *cpuc) 1389 { 1390 u64 from, to; 1391 int br_sel = cpuc->br_sel; 1392 int i, j, type, to_plm; 1393 bool compress = false; 1394 1395 /* if sampling all branches, then nothing to filter */ 1396 if (((br_sel & X86_BR_ALL) == X86_BR_ALL) && 1397 ((br_sel & X86_BR_TYPE_SAVE) != X86_BR_TYPE_SAVE)) 1398 return; 1399 1400 for (i = 0; i < cpuc->lbr_stack.nr; i++) { 1401 1402 from = cpuc->lbr_entries[i].from; 1403 to = cpuc->lbr_entries[i].to; 1404 type = cpuc->lbr_entries[i].type; 1405 1406 /* 1407 * Parse the branch type recorded in LBR_x_INFO MSR. 1408 * Doesn't support OTHER_BRANCH decoding for now. 1409 * OTHER_BRANCH branch type still rely on software decoding. 1410 */ 1411 if (static_cpu_has(X86_FEATURE_ARCH_LBR) && 1412 type <= ARCH_LBR_BR_TYPE_KNOWN_MAX) { 1413 to_plm = kernel_ip(to) ? X86_BR_KERNEL : X86_BR_USER; 1414 type = arch_lbr_br_type_map[type] | to_plm; 1415 } else 1416 type = branch_type(from, to, cpuc->lbr_entries[i].abort); 1417 if (type != X86_BR_NONE && (br_sel & X86_BR_ANYTX)) { 1418 if (cpuc->lbr_entries[i].in_tx) 1419 type |= X86_BR_IN_TX; 1420 else 1421 type |= X86_BR_NO_TX; 1422 } 1423 1424 /* if type does not correspond, then discard */ 1425 if (type == X86_BR_NONE || (br_sel & type) != type) { 1426 cpuc->lbr_entries[i].from = 0; 1427 compress = true; 1428 } 1429 1430 if ((br_sel & X86_BR_TYPE_SAVE) == X86_BR_TYPE_SAVE) 1431 cpuc->lbr_entries[i].type = common_branch_type(type); 1432 } 1433 1434 if (!compress) 1435 return; 1436 1437 /* remove all entries with from=0 */ 1438 for (i = 0; i < cpuc->lbr_stack.nr; ) { 1439 if (!cpuc->lbr_entries[i].from) { 1440 j = i; 1441 while (++j < cpuc->lbr_stack.nr) 1442 cpuc->lbr_entries[j-1] = cpuc->lbr_entries[j]; 1443 cpuc->lbr_stack.nr--; 1444 if (!cpuc->lbr_entries[i].from) 1445 continue; 1446 } 1447 i++; 1448 } 1449 } 1450 1451 void intel_pmu_store_pebs_lbrs(struct lbr_entry *lbr) 1452 { 1453 struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); 1454 1455 /* Cannot get TOS for large PEBS and Arch LBR */ 1456 if (static_cpu_has(X86_FEATURE_ARCH_LBR) || 1457 (cpuc->n_pebs == cpuc->n_large_pebs)) 1458 cpuc->lbr_stack.hw_idx = -1ULL; 1459 else 1460 cpuc->lbr_stack.hw_idx = intel_pmu_lbr_tos(); 1461 1462 intel_pmu_store_lbr(cpuc, lbr); 1463 intel_pmu_lbr_filter(cpuc); 1464 } 1465 1466 /* 1467 * Map interface branch filters onto LBR filters 1468 */ 1469 static const int nhm_lbr_sel_map[PERF_SAMPLE_BRANCH_MAX_SHIFT] = { 1470 [PERF_SAMPLE_BRANCH_ANY_SHIFT] = LBR_ANY, 1471 [PERF_SAMPLE_BRANCH_USER_SHIFT] = LBR_USER, 1472 [PERF_SAMPLE_BRANCH_KERNEL_SHIFT] = LBR_KERNEL, 1473 [PERF_SAMPLE_BRANCH_HV_SHIFT] = LBR_IGN, 1474 [PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT] = LBR_RETURN | LBR_REL_JMP 1475 | LBR_IND_JMP | LBR_FAR, 1476 /* 1477 * NHM/WSM erratum: must include REL_JMP+IND_JMP to get CALL branches 1478 */ 1479 [PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT] = 1480 LBR_REL_CALL | LBR_IND_CALL | LBR_REL_JMP | LBR_IND_JMP | LBR_FAR, 1481 /* 1482 * NHM/WSM erratum: must include IND_JMP to capture IND_CALL 1483 */ 1484 [PERF_SAMPLE_BRANCH_IND_CALL_SHIFT] = LBR_IND_CALL | LBR_IND_JMP, 1485 [PERF_SAMPLE_BRANCH_COND_SHIFT] = LBR_JCC, 1486 [PERF_SAMPLE_BRANCH_IND_JUMP_SHIFT] = LBR_IND_JMP, 1487 }; 1488 1489 static const int snb_lbr_sel_map[PERF_SAMPLE_BRANCH_MAX_SHIFT] = { 1490 [PERF_SAMPLE_BRANCH_ANY_SHIFT] = LBR_ANY, 1491 [PERF_SAMPLE_BRANCH_USER_SHIFT] = LBR_USER, 1492 [PERF_SAMPLE_BRANCH_KERNEL_SHIFT] = LBR_KERNEL, 1493 [PERF_SAMPLE_BRANCH_HV_SHIFT] = LBR_IGN, 1494 [PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT] = LBR_RETURN | LBR_FAR, 1495 [PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT] = LBR_REL_CALL | LBR_IND_CALL 1496 | LBR_FAR, 1497 [PERF_SAMPLE_BRANCH_IND_CALL_SHIFT] = LBR_IND_CALL, 1498 [PERF_SAMPLE_BRANCH_COND_SHIFT] = LBR_JCC, 1499 [PERF_SAMPLE_BRANCH_IND_JUMP_SHIFT] = LBR_IND_JMP, 1500 [PERF_SAMPLE_BRANCH_CALL_SHIFT] = LBR_REL_CALL, 1501 }; 1502 1503 static const int hsw_lbr_sel_map[PERF_SAMPLE_BRANCH_MAX_SHIFT] = { 1504 [PERF_SAMPLE_BRANCH_ANY_SHIFT] = LBR_ANY, 1505 [PERF_SAMPLE_BRANCH_USER_SHIFT] = LBR_USER, 1506 [PERF_SAMPLE_BRANCH_KERNEL_SHIFT] = LBR_KERNEL, 1507 [PERF_SAMPLE_BRANCH_HV_SHIFT] = LBR_IGN, 1508 [PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT] = LBR_RETURN | LBR_FAR, 1509 [PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT] = LBR_REL_CALL | LBR_IND_CALL 1510 | LBR_FAR, 1511 [PERF_SAMPLE_BRANCH_IND_CALL_SHIFT] = LBR_IND_CALL, 1512 [PERF_SAMPLE_BRANCH_COND_SHIFT] = LBR_JCC, 1513 [PERF_SAMPLE_BRANCH_CALL_STACK_SHIFT] = LBR_REL_CALL | LBR_IND_CALL 1514 | LBR_RETURN | LBR_CALL_STACK, 1515 [PERF_SAMPLE_BRANCH_IND_JUMP_SHIFT] = LBR_IND_JMP, 1516 [PERF_SAMPLE_BRANCH_CALL_SHIFT] = LBR_REL_CALL, 1517 }; 1518 1519 static int arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_MAX_SHIFT] = { 1520 [PERF_SAMPLE_BRANCH_ANY_SHIFT] = ARCH_LBR_ANY, 1521 [PERF_SAMPLE_BRANCH_USER_SHIFT] = ARCH_LBR_USER, 1522 [PERF_SAMPLE_BRANCH_KERNEL_SHIFT] = ARCH_LBR_KERNEL, 1523 [PERF_SAMPLE_BRANCH_HV_SHIFT] = LBR_IGN, 1524 [PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT] = ARCH_LBR_RETURN | 1525 ARCH_LBR_OTHER_BRANCH, 1526 [PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT] = ARCH_LBR_REL_CALL | 1527 ARCH_LBR_IND_CALL | 1528 ARCH_LBR_OTHER_BRANCH, 1529 [PERF_SAMPLE_BRANCH_IND_CALL_SHIFT] = ARCH_LBR_IND_CALL, 1530 [PERF_SAMPLE_BRANCH_COND_SHIFT] = ARCH_LBR_JCC, 1531 [PERF_SAMPLE_BRANCH_CALL_STACK_SHIFT] = ARCH_LBR_REL_CALL | 1532 ARCH_LBR_IND_CALL | 1533 ARCH_LBR_RETURN | 1534 ARCH_LBR_CALL_STACK, 1535 [PERF_SAMPLE_BRANCH_IND_JUMP_SHIFT] = ARCH_LBR_IND_JMP, 1536 [PERF_SAMPLE_BRANCH_CALL_SHIFT] = ARCH_LBR_REL_CALL, 1537 }; 1538 1539 /* core */ 1540 void __init intel_pmu_lbr_init_core(void) 1541 { 1542 x86_pmu.lbr_nr = 4; 1543 x86_pmu.lbr_tos = MSR_LBR_TOS; 1544 x86_pmu.lbr_from = MSR_LBR_CORE_FROM; 1545 x86_pmu.lbr_to = MSR_LBR_CORE_TO; 1546 1547 /* 1548 * SW branch filter usage: 1549 * - compensate for lack of HW filter 1550 */ 1551 } 1552 1553 /* nehalem/westmere */ 1554 void __init intel_pmu_lbr_init_nhm(void) 1555 { 1556 x86_pmu.lbr_nr = 16; 1557 x86_pmu.lbr_tos = MSR_LBR_TOS; 1558 x86_pmu.lbr_from = MSR_LBR_NHM_FROM; 1559 x86_pmu.lbr_to = MSR_LBR_NHM_TO; 1560 1561 x86_pmu.lbr_sel_mask = LBR_SEL_MASK; 1562 x86_pmu.lbr_sel_map = nhm_lbr_sel_map; 1563 1564 /* 1565 * SW branch filter usage: 1566 * - workaround LBR_SEL errata (see above) 1567 * - support syscall, sysret capture. 1568 * That requires LBR_FAR but that means far 1569 * jmp need to be filtered out 1570 */ 1571 } 1572 1573 /* sandy bridge */ 1574 void __init intel_pmu_lbr_init_snb(void) 1575 { 1576 x86_pmu.lbr_nr = 16; 1577 x86_pmu.lbr_tos = MSR_LBR_TOS; 1578 x86_pmu.lbr_from = MSR_LBR_NHM_FROM; 1579 x86_pmu.lbr_to = MSR_LBR_NHM_TO; 1580 1581 x86_pmu.lbr_sel_mask = LBR_SEL_MASK; 1582 x86_pmu.lbr_sel_map = snb_lbr_sel_map; 1583 1584 /* 1585 * SW branch filter usage: 1586 * - support syscall, sysret capture. 1587 * That requires LBR_FAR but that means far 1588 * jmp need to be filtered out 1589 */ 1590 } 1591 1592 static inline struct kmem_cache * 1593 create_lbr_kmem_cache(size_t size, size_t align) 1594 { 1595 return kmem_cache_create("x86_lbr", size, align, 0, NULL); 1596 } 1597 1598 /* haswell */ 1599 void intel_pmu_lbr_init_hsw(void) 1600 { 1601 size_t size = sizeof(struct x86_perf_task_context); 1602 1603 x86_pmu.lbr_nr = 16; 1604 x86_pmu.lbr_tos = MSR_LBR_TOS; 1605 x86_pmu.lbr_from = MSR_LBR_NHM_FROM; 1606 x86_pmu.lbr_to = MSR_LBR_NHM_TO; 1607 1608 x86_pmu.lbr_sel_mask = LBR_SEL_MASK; 1609 x86_pmu.lbr_sel_map = hsw_lbr_sel_map; 1610 1611 x86_get_pmu(smp_processor_id())->task_ctx_cache = create_lbr_kmem_cache(size, 0); 1612 } 1613 1614 /* skylake */ 1615 __init void intel_pmu_lbr_init_skl(void) 1616 { 1617 size_t size = sizeof(struct x86_perf_task_context); 1618 1619 x86_pmu.lbr_nr = 32; 1620 x86_pmu.lbr_tos = MSR_LBR_TOS; 1621 x86_pmu.lbr_from = MSR_LBR_NHM_FROM; 1622 x86_pmu.lbr_to = MSR_LBR_NHM_TO; 1623 x86_pmu.lbr_info = MSR_LBR_INFO_0; 1624 1625 x86_pmu.lbr_sel_mask = LBR_SEL_MASK; 1626 x86_pmu.lbr_sel_map = hsw_lbr_sel_map; 1627 1628 x86_get_pmu(smp_processor_id())->task_ctx_cache = create_lbr_kmem_cache(size, 0); 1629 1630 /* 1631 * SW branch filter usage: 1632 * - support syscall, sysret capture. 1633 * That requires LBR_FAR but that means far 1634 * jmp need to be filtered out 1635 */ 1636 } 1637 1638 /* atom */ 1639 void __init intel_pmu_lbr_init_atom(void) 1640 { 1641 /* 1642 * only models starting at stepping 10 seems 1643 * to have an operational LBR which can freeze 1644 * on PMU interrupt 1645 */ 1646 if (boot_cpu_data.x86_model == 28 1647 && boot_cpu_data.x86_stepping < 10) { 1648 pr_cont("LBR disabled due to erratum"); 1649 return; 1650 } 1651 1652 x86_pmu.lbr_nr = 8; 1653 x86_pmu.lbr_tos = MSR_LBR_TOS; 1654 x86_pmu.lbr_from = MSR_LBR_CORE_FROM; 1655 x86_pmu.lbr_to = MSR_LBR_CORE_TO; 1656 1657 /* 1658 * SW branch filter usage: 1659 * - compensate for lack of HW filter 1660 */ 1661 } 1662 1663 /* slm */ 1664 void __init intel_pmu_lbr_init_slm(void) 1665 { 1666 x86_pmu.lbr_nr = 8; 1667 x86_pmu.lbr_tos = MSR_LBR_TOS; 1668 x86_pmu.lbr_from = MSR_LBR_CORE_FROM; 1669 x86_pmu.lbr_to = MSR_LBR_CORE_TO; 1670 1671 x86_pmu.lbr_sel_mask = LBR_SEL_MASK; 1672 x86_pmu.lbr_sel_map = nhm_lbr_sel_map; 1673 1674 /* 1675 * SW branch filter usage: 1676 * - compensate for lack of HW filter 1677 */ 1678 pr_cont("8-deep LBR, "); 1679 } 1680 1681 /* Knights Landing */ 1682 void intel_pmu_lbr_init_knl(void) 1683 { 1684 x86_pmu.lbr_nr = 8; 1685 x86_pmu.lbr_tos = MSR_LBR_TOS; 1686 x86_pmu.lbr_from = MSR_LBR_NHM_FROM; 1687 x86_pmu.lbr_to = MSR_LBR_NHM_TO; 1688 1689 x86_pmu.lbr_sel_mask = LBR_SEL_MASK; 1690 x86_pmu.lbr_sel_map = snb_lbr_sel_map; 1691 1692 /* Knights Landing does have MISPREDICT bit */ 1693 if (x86_pmu.intel_cap.lbr_format == LBR_FORMAT_LIP) 1694 x86_pmu.intel_cap.lbr_format = LBR_FORMAT_EIP_FLAGS; 1695 } 1696 1697 void intel_pmu_lbr_init(void) 1698 { 1699 switch (x86_pmu.intel_cap.lbr_format) { 1700 case LBR_FORMAT_EIP_FLAGS2: 1701 x86_pmu.lbr_has_tsx = 1; 1702 x86_pmu.lbr_from_flags = 1; 1703 if (lbr_from_signext_quirk_needed()) 1704 static_branch_enable(&lbr_from_quirk_key); 1705 break; 1706 1707 case LBR_FORMAT_EIP_FLAGS: 1708 x86_pmu.lbr_from_flags = 1; 1709 break; 1710 1711 case LBR_FORMAT_INFO: 1712 x86_pmu.lbr_has_tsx = 1; 1713 fallthrough; 1714 case LBR_FORMAT_INFO2: 1715 x86_pmu.lbr_has_info = 1; 1716 break; 1717 1718 case LBR_FORMAT_TIME: 1719 x86_pmu.lbr_from_flags = 1; 1720 x86_pmu.lbr_to_cycles = 1; 1721 break; 1722 } 1723 1724 if (x86_pmu.lbr_has_info) { 1725 /* 1726 * Only used in combination with baseline pebs. 1727 */ 1728 static_branch_enable(&x86_lbr_mispred); 1729 static_branch_enable(&x86_lbr_cycles); 1730 } 1731 } 1732 1733 /* 1734 * LBR state size is variable based on the max number of registers. 1735 * This calculates the expected state size, which should match 1736 * what the hardware enumerates for the size of XFEATURE_LBR. 1737 */ 1738 static inline unsigned int get_lbr_state_size(void) 1739 { 1740 return sizeof(struct arch_lbr_state) + 1741 x86_pmu.lbr_nr * sizeof(struct lbr_entry); 1742 } 1743 1744 static bool is_arch_lbr_xsave_available(void) 1745 { 1746 if (!boot_cpu_has(X86_FEATURE_XSAVES)) 1747 return false; 1748 1749 /* 1750 * Check the LBR state with the corresponding software structure. 1751 * Disable LBR XSAVES support if the size doesn't match. 1752 */ 1753 if (xfeature_size(XFEATURE_LBR) == 0) 1754 return false; 1755 1756 if (WARN_ON(xfeature_size(XFEATURE_LBR) != get_lbr_state_size())) 1757 return false; 1758 1759 return true; 1760 } 1761 1762 void __init intel_pmu_arch_lbr_init(void) 1763 { 1764 struct pmu *pmu = x86_get_pmu(smp_processor_id()); 1765 union cpuid28_eax eax; 1766 union cpuid28_ebx ebx; 1767 union cpuid28_ecx ecx; 1768 unsigned int unused_edx; 1769 bool arch_lbr_xsave; 1770 size_t size; 1771 u64 lbr_nr; 1772 1773 /* Arch LBR Capabilities */ 1774 cpuid(28, &eax.full, &ebx.full, &ecx.full, &unused_edx); 1775 1776 lbr_nr = fls(eax.split.lbr_depth_mask) * 8; 1777 if (!lbr_nr) 1778 goto clear_arch_lbr; 1779 1780 /* Apply the max depth of Arch LBR */ 1781 if (wrmsrl_safe(MSR_ARCH_LBR_DEPTH, lbr_nr)) 1782 goto clear_arch_lbr; 1783 1784 x86_pmu.lbr_depth_mask = eax.split.lbr_depth_mask; 1785 x86_pmu.lbr_deep_c_reset = eax.split.lbr_deep_c_reset; 1786 x86_pmu.lbr_lip = eax.split.lbr_lip; 1787 x86_pmu.lbr_cpl = ebx.split.lbr_cpl; 1788 x86_pmu.lbr_filter = ebx.split.lbr_filter; 1789 x86_pmu.lbr_call_stack = ebx.split.lbr_call_stack; 1790 x86_pmu.lbr_mispred = ecx.split.lbr_mispred; 1791 x86_pmu.lbr_timed_lbr = ecx.split.lbr_timed_lbr; 1792 x86_pmu.lbr_br_type = ecx.split.lbr_br_type; 1793 x86_pmu.lbr_nr = lbr_nr; 1794 1795 if (x86_pmu.lbr_mispred) 1796 static_branch_enable(&x86_lbr_mispred); 1797 if (x86_pmu.lbr_timed_lbr) 1798 static_branch_enable(&x86_lbr_cycles); 1799 if (x86_pmu.lbr_br_type) 1800 static_branch_enable(&x86_lbr_type); 1801 1802 arch_lbr_xsave = is_arch_lbr_xsave_available(); 1803 if (arch_lbr_xsave) { 1804 size = sizeof(struct x86_perf_task_context_arch_lbr_xsave) + 1805 get_lbr_state_size(); 1806 pmu->task_ctx_cache = create_lbr_kmem_cache(size, 1807 XSAVE_ALIGNMENT); 1808 } 1809 1810 if (!pmu->task_ctx_cache) { 1811 arch_lbr_xsave = false; 1812 1813 size = sizeof(struct x86_perf_task_context_arch_lbr) + 1814 lbr_nr * sizeof(struct lbr_entry); 1815 pmu->task_ctx_cache = create_lbr_kmem_cache(size, 0); 1816 } 1817 1818 x86_pmu.lbr_from = MSR_ARCH_LBR_FROM_0; 1819 x86_pmu.lbr_to = MSR_ARCH_LBR_TO_0; 1820 x86_pmu.lbr_info = MSR_ARCH_LBR_INFO_0; 1821 1822 /* LBR callstack requires both CPL and Branch Filtering support */ 1823 if (!x86_pmu.lbr_cpl || 1824 !x86_pmu.lbr_filter || 1825 !x86_pmu.lbr_call_stack) 1826 arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_CALL_STACK_SHIFT] = LBR_NOT_SUPP; 1827 1828 if (!x86_pmu.lbr_cpl) { 1829 arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_USER_SHIFT] = LBR_NOT_SUPP; 1830 arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_KERNEL_SHIFT] = LBR_NOT_SUPP; 1831 } else if (!x86_pmu.lbr_filter) { 1832 arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_ANY_SHIFT] = LBR_NOT_SUPP; 1833 arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT] = LBR_NOT_SUPP; 1834 arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT] = LBR_NOT_SUPP; 1835 arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_IND_CALL_SHIFT] = LBR_NOT_SUPP; 1836 arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_COND_SHIFT] = LBR_NOT_SUPP; 1837 arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_IND_JUMP_SHIFT] = LBR_NOT_SUPP; 1838 arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_CALL_SHIFT] = LBR_NOT_SUPP; 1839 } 1840 1841 x86_pmu.lbr_ctl_mask = ARCH_LBR_CTL_MASK; 1842 x86_pmu.lbr_ctl_map = arch_lbr_ctl_map; 1843 1844 if (!x86_pmu.lbr_cpl && !x86_pmu.lbr_filter) 1845 x86_pmu.lbr_ctl_map = NULL; 1846 1847 x86_pmu.lbr_reset = intel_pmu_arch_lbr_reset; 1848 if (arch_lbr_xsave) { 1849 x86_pmu.lbr_save = intel_pmu_arch_lbr_xsaves; 1850 x86_pmu.lbr_restore = intel_pmu_arch_lbr_xrstors; 1851 x86_pmu.lbr_read = intel_pmu_arch_lbr_read_xsave; 1852 pr_cont("XSAVE "); 1853 } else { 1854 x86_pmu.lbr_save = intel_pmu_arch_lbr_save; 1855 x86_pmu.lbr_restore = intel_pmu_arch_lbr_restore; 1856 x86_pmu.lbr_read = intel_pmu_arch_lbr_read; 1857 } 1858 1859 pr_cont("Architectural LBR, "); 1860 1861 return; 1862 1863 clear_arch_lbr: 1864 clear_cpu_cap(&boot_cpu_data, X86_FEATURE_ARCH_LBR); 1865 } 1866 1867 /** 1868 * x86_perf_get_lbr - get the LBR records information 1869 * 1870 * @lbr: the caller's memory to store the LBR records information 1871 * 1872 * Returns: 0 indicates the LBR info has been successfully obtained 1873 */ 1874 int x86_perf_get_lbr(struct x86_pmu_lbr *lbr) 1875 { 1876 int lbr_fmt = x86_pmu.intel_cap.lbr_format; 1877 1878 lbr->nr = x86_pmu.lbr_nr; 1879 lbr->from = x86_pmu.lbr_from; 1880 lbr->to = x86_pmu.lbr_to; 1881 lbr->info = (lbr_fmt == LBR_FORMAT_INFO) ? x86_pmu.lbr_info : 0; 1882 1883 return 0; 1884 } 1885 EXPORT_SYMBOL_GPL(x86_perf_get_lbr); 1886 1887 struct event_constraint vlbr_constraint = 1888 __EVENT_CONSTRAINT(INTEL_FIXED_VLBR_EVENT, (1ULL << INTEL_PMC_IDX_FIXED_VLBR), 1889 FIXED_EVENT_FLAGS, 1, 0, PERF_X86_EVENT_LBR_SELECT); 1890