| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Kan Liang | 2570 | 36.62% | 28 | 27.18% |
| Stéphane Eranian | 1525 | 21.73% | 11 | 10.68% |
| Peter Zijlstra | 1042 | 14.85% | 12 | 11.65% |
| Yan Zheng | 575 | 8.19% | 7 | 6.80% |
| Andi Kleen | 498 | 7.10% | 13 | 12.62% |
| Like Xu | 258 | 3.68% | 4 | 3.88% |
| Jin Yao | 158 | 2.25% | 1 | 0.97% |
| David Carrillo-Cisneros | 107 | 1.52% | 3 | 2.91% |
| Alexey Budankov | 65 | 0.93% | 1 | 0.97% |
| Harish Chegondi | 44 | 0.63% | 1 | 0.97% |
| Dave Hansen | 27 | 0.38% | 1 | 0.97% |
| Anshuman Khandual | 22 | 0.31% | 2 | 1.94% |
| jacek.tomaka@poczta.fm | 19 | 0.27% | 1 | 0.97% |
| Wanpeng Li | 19 | 0.27% | 1 | 0.97% |
| Jiri Olsa | 18 | 0.26% | 1 | 0.97% |
| Kevin Winchester | 14 | 0.20% | 1 | 0.97% |
| Song Liu | 13 | 0.19% | 1 | 0.97% |
| Christoph Lameter | 12 | 0.17% | 1 | 0.97% |
| Borislav Petkov | 12 | 0.17% | 2 | 1.94% |
| Thomas Gleixner | 5 | 0.07% | 2 | 1.94% |
| Mathias Krause | 4 | 0.06% | 1 | 0.97% |
| Gabriel Krisman Bertazi | 3 | 0.04% | 1 | 0.97% |
| Gustavo A. R. Silva | 2 | 0.03% | 1 | 0.97% |
| Greg Kroah-Hartman | 1 | 0.01% | 1 | 0.97% |
| Valdis Kletnieks | 1 | 0.01% | 1 | 0.97% |
| Adam Buchbinder | 1 | 0.01% | 1 | 0.97% |
| Colin Ian King | 1 | 0.01% | 1 | 0.97% |
| jia zhang | 1 | 0.01% | 1 | 0.97% |
| Ingo Molnar | 1 | 0.01% | 1 | 0.97% |
| Total | 7018 | 103 |
// SPDX-License-Identifier: GPL-2.0 #include <linux/perf_event.h> #include <linux/types.h> #include <asm/perf_event.h> #include <asm/msr.h> #include <asm/insn.h> #include "../perf_event.h" /* * Intel LBR_SELECT bits * Intel Vol3a, April 2011, Section 16.7 Table 16-10 * * Hardware branch filter (not available on all CPUs) */ #define LBR_KERNEL_BIT 0 /* do not capture at ring0 */ #define LBR_USER_BIT 1 /* do not capture at ring > 0 */ #define LBR_JCC_BIT 2 /* do not capture conditional branches */ #define LBR_REL_CALL_BIT 3 /* do not capture relative calls */ #define LBR_IND_CALL_BIT 4 /* do not capture indirect calls */ #define LBR_RETURN_BIT 5 /* do not capture near returns */ #define LBR_IND_JMP_BIT 6 /* do not capture indirect jumps */ #define LBR_REL_JMP_BIT 7 /* do not capture relative jumps */ #define LBR_FAR_BIT 8 /* do not capture far branches */ #define LBR_CALL_STACK_BIT 9 /* enable call stack */ /* * Following bit only exists in Linux; we mask it out before writing it to * the actual MSR. But it helps the constraint perf code to understand * that this is a separate configuration. */ #define LBR_NO_INFO_BIT 63 /* don't read LBR_INFO. */ #define LBR_KERNEL (1 << LBR_KERNEL_BIT) #define LBR_USER (1 << LBR_USER_BIT) #define LBR_JCC (1 << LBR_JCC_BIT) #define LBR_REL_CALL (1 << LBR_REL_CALL_BIT) #define LBR_IND_CALL (1 << LBR_IND_CALL_BIT) #define LBR_RETURN (1 << LBR_RETURN_BIT) #define LBR_REL_JMP (1 << LBR_REL_JMP_BIT) #define LBR_IND_JMP (1 << LBR_IND_JMP_BIT) #define LBR_FAR (1 << LBR_FAR_BIT) #define LBR_CALL_STACK (1 << LBR_CALL_STACK_BIT) #define LBR_NO_INFO (1ULL << LBR_NO_INFO_BIT) #define LBR_PLM (LBR_KERNEL | LBR_USER) #define LBR_SEL_MASK 0x3ff /* valid bits in LBR_SELECT */ #define LBR_NOT_SUPP -1 /* LBR filter not supported */ #define LBR_IGN 0 /* ignored */ #define LBR_ANY \ (LBR_JCC |\ LBR_REL_CALL |\ LBR_IND_CALL |\ LBR_RETURN |\ LBR_REL_JMP |\ LBR_IND_JMP |\ LBR_FAR) #define LBR_FROM_FLAG_MISPRED BIT_ULL(63) #define LBR_FROM_FLAG_IN_TX BIT_ULL(62) #define LBR_FROM_FLAG_ABORT BIT_ULL(61) #define LBR_FROM_SIGNEXT_2MSB (BIT_ULL(60) | BIT_ULL(59)) /* * x86control flow change classification * x86control flow changes include branches, interrupts, traps, faults */ enum { X86_BR_NONE = 0, /* unknown */ X86_BR_USER = 1 << 0, /* branch target is user */ X86_BR_KERNEL = 1 << 1, /* branch target is kernel */ X86_BR_CALL = 1 << 2, /* call */ X86_BR_RET = 1 << 3, /* return */ X86_BR_SYSCALL = 1 << 4, /* syscall */ X86_BR_SYSRET = 1 << 5, /* syscall return */ X86_BR_INT = 1 << 6, /* sw interrupt */ X86_BR_IRET = 1 << 7, /* return from interrupt */ X86_BR_JCC = 1 << 8, /* conditional */ X86_BR_JMP = 1 << 9, /* jump */ X86_BR_IRQ = 1 << 10,/* hw interrupt or trap or fault */ X86_BR_IND_CALL = 1 << 11,/* indirect calls */ X86_BR_ABORT = 1 << 12,/* transaction abort */ X86_BR_IN_TX = 1 << 13,/* in transaction */ X86_BR_NO_TX = 1 << 14,/* not in transaction */ X86_BR_ZERO_CALL = 1 << 15,/* zero length call */ X86_BR_CALL_STACK = 1 << 16,/* call stack */ X86_BR_IND_JMP = 1 << 17,/* indirect jump */ X86_BR_TYPE_SAVE = 1 << 18,/* indicate to save branch type */ }; #define X86_BR_PLM (X86_BR_USER | X86_BR_KERNEL) #define X86_BR_ANYTX (X86_BR_NO_TX | X86_BR_IN_TX) #define X86_BR_ANY \ (X86_BR_CALL |\ X86_BR_RET |\ X86_BR_SYSCALL |\ X86_BR_SYSRET |\ X86_BR_INT |\ X86_BR_IRET |\ X86_BR_JCC |\ X86_BR_JMP |\ X86_BR_IRQ |\ X86_BR_ABORT |\ X86_BR_IND_CALL |\ X86_BR_IND_JMP |\ X86_BR_ZERO_CALL) #define X86_BR_ALL (X86_BR_PLM | X86_BR_ANY) #define X86_BR_ANY_CALL \ (X86_BR_CALL |\ X86_BR_IND_CALL |\ X86_BR_ZERO_CALL |\ X86_BR_SYSCALL |\ X86_BR_IRQ |\ X86_BR_INT) /* * Intel LBR_CTL bits * * Hardware branch filter for Arch LBR */ #define ARCH_LBR_KERNEL_BIT 1 /* capture at ring0 */ #define ARCH_LBR_USER_BIT 2 /* capture at ring > 0 */ #define ARCH_LBR_CALL_STACK_BIT 3 /* enable call stack */ #define ARCH_LBR_JCC_BIT 16 /* capture conditional branches */ #define ARCH_LBR_REL_JMP_BIT 17 /* capture relative jumps */ #define ARCH_LBR_IND_JMP_BIT 18 /* capture indirect jumps */ #define ARCH_LBR_REL_CALL_BIT 19 /* capture relative calls */ #define ARCH_LBR_IND_CALL_BIT 20 /* capture indirect calls */ #define ARCH_LBR_RETURN_BIT 21 /* capture near returns */ #define ARCH_LBR_OTHER_BRANCH_BIT 22 /* capture other branches */ #define ARCH_LBR_KERNEL (1ULL << ARCH_LBR_KERNEL_BIT) #define ARCH_LBR_USER (1ULL << ARCH_LBR_USER_BIT) #define ARCH_LBR_CALL_STACK (1ULL << ARCH_LBR_CALL_STACK_BIT) #define ARCH_LBR_JCC (1ULL << ARCH_LBR_JCC_BIT) #define ARCH_LBR_REL_JMP (1ULL << ARCH_LBR_REL_JMP_BIT) #define ARCH_LBR_IND_JMP (1ULL << ARCH_LBR_IND_JMP_BIT) #define ARCH_LBR_REL_CALL (1ULL << ARCH_LBR_REL_CALL_BIT) #define ARCH_LBR_IND_CALL (1ULL << ARCH_LBR_IND_CALL_BIT) #define ARCH_LBR_RETURN (1ULL << ARCH_LBR_RETURN_BIT) #define ARCH_LBR_OTHER_BRANCH (1ULL << ARCH_LBR_OTHER_BRANCH_BIT) #define ARCH_LBR_ANY \ (ARCH_LBR_JCC |\ ARCH_LBR_REL_JMP |\ ARCH_LBR_IND_JMP |\ ARCH_LBR_REL_CALL |\ ARCH_LBR_IND_CALL |\ ARCH_LBR_RETURN |\ ARCH_LBR_OTHER_BRANCH) #define ARCH_LBR_CTL_MASK 0x7f000e static void intel_pmu_lbr_filter(struct cpu_hw_events *cpuc); static __always_inline bool is_lbr_call_stack_bit_set(u64 config) { if (static_cpu_has(X86_FEATURE_ARCH_LBR)) return !!(config & ARCH_LBR_CALL_STACK); return !!(config & LBR_CALL_STACK); } /* * We only support LBR implementations that have FREEZE_LBRS_ON_PMI * otherwise it becomes near impossible to get a reliable stack. */ static void __intel_pmu_lbr_enable(bool pmi) { struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); u64 debugctl, lbr_select = 0, orig_debugctl; /* * No need to unfreeze manually, as v4 can do that as part * of the GLOBAL_STATUS ack. */ if (pmi && x86_pmu.version >= 4) return; /* * No need to reprogram LBR_SELECT in a PMI, as it * did not change. */ if (cpuc->lbr_sel) lbr_select = cpuc->lbr_sel->config & x86_pmu.lbr_sel_mask; if (!static_cpu_has(X86_FEATURE_ARCH_LBR) && !pmi && cpuc->lbr_sel) wrmsrl(MSR_LBR_SELECT, lbr_select); rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctl); orig_debugctl = debugctl; if (!static_cpu_has(X86_FEATURE_ARCH_LBR)) debugctl |= DEBUGCTLMSR_LBR; /* * LBR callstack does not work well with FREEZE_LBRS_ON_PMI. * If FREEZE_LBRS_ON_PMI is set, PMI near call/return instructions * may cause superfluous increase/decrease of LBR_TOS. */ if (is_lbr_call_stack_bit_set(lbr_select)) debugctl &= ~DEBUGCTLMSR_FREEZE_LBRS_ON_PMI; else debugctl |= DEBUGCTLMSR_FREEZE_LBRS_ON_PMI; if (orig_debugctl != debugctl) wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctl); if (static_cpu_has(X86_FEATURE_ARCH_LBR)) wrmsrl(MSR_ARCH_LBR_CTL, lbr_select | ARCH_LBR_CTL_LBREN); } void intel_pmu_lbr_reset_32(void) { int i; for (i = 0; i < x86_pmu.lbr_nr; i++) wrmsrl(x86_pmu.lbr_from + i, 0); } void intel_pmu_lbr_reset_64(void) { int i; for (i = 0; i < x86_pmu.lbr_nr; i++) { wrmsrl(x86_pmu.lbr_from + i, 0); wrmsrl(x86_pmu.lbr_to + i, 0); if (x86_pmu.lbr_has_info) wrmsrl(x86_pmu.lbr_info + i, 0); } } static void intel_pmu_arch_lbr_reset(void) { /* Write to ARCH_LBR_DEPTH MSR, all LBR entries are reset to 0 */ wrmsrl(MSR_ARCH_LBR_DEPTH, x86_pmu.lbr_nr); } void intel_pmu_lbr_reset(void) { struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); if (!x86_pmu.lbr_nr) return; x86_pmu.lbr_reset(); cpuc->last_task_ctx = NULL; cpuc->last_log_id = 0; if (!static_cpu_has(X86_FEATURE_ARCH_LBR) && cpuc->lbr_select) wrmsrl(MSR_LBR_SELECT, 0); } /* * TOS = most recently recorded branch */ static inline u64 intel_pmu_lbr_tos(void) { u64 tos; rdmsrl(x86_pmu.lbr_tos, tos); return tos; } enum { LBR_NONE, LBR_VALID, }; /* * For format LBR_FORMAT_EIP_FLAGS2, bits 61:62 in MSR_LAST_BRANCH_FROM_x * are the TSX flags when TSX is supported, but when TSX is not supported * they have no consistent behavior: * * - For wrmsr(), bits 61:62 are considered part of the sign extension. * - For HW updates (branch captures) bits 61:62 are always OFF and are not * part of the sign extension. * * Therefore, if: * * 1) LBR format LBR_FORMAT_EIP_FLAGS2 * 2) CPU has no TSX support enabled * * ... then any value passed to wrmsr() must be sign extended to 63 bits and any * value from rdmsr() must be converted to have a 61 bits sign extension, * ignoring the TSX flags. */ static inline bool lbr_from_signext_quirk_needed(void) { bool tsx_support = boot_cpu_has(X86_FEATURE_HLE) || boot_cpu_has(X86_FEATURE_RTM); return !tsx_support; } static DEFINE_STATIC_KEY_FALSE(lbr_from_quirk_key); /* If quirk is enabled, ensure sign extension is 63 bits: */ inline u64 lbr_from_signext_quirk_wr(u64 val) { if (static_branch_unlikely(&lbr_from_quirk_key)) { /* * Sign extend into bits 61:62 while preserving bit 63. * * Quirk is enabled when TSX is disabled. Therefore TSX bits * in val are always OFF and must be changed to be sign * extension bits. Since bits 59:60 are guaranteed to be * part of the sign extension bits, we can just copy them * to 61:62. */ val |= (LBR_FROM_SIGNEXT_2MSB & val) << 2; } return val; } /* * If quirk is needed, ensure sign extension is 61 bits: */ static u64 lbr_from_signext_quirk_rd(u64 val) { if (static_branch_unlikely(&lbr_from_quirk_key)) { /* * Quirk is on when TSX is not enabled. Therefore TSX * flags must be read as OFF. */ val &= ~(LBR_FROM_FLAG_IN_TX | LBR_FROM_FLAG_ABORT); } return val; } static __always_inline void wrlbr_from(unsigned int idx, u64 val) { val = lbr_from_signext_quirk_wr(val); wrmsrl(x86_pmu.lbr_from + idx, val); } static __always_inline void wrlbr_to(unsigned int idx, u64 val) { wrmsrl(x86_pmu.lbr_to + idx, val); } static __always_inline void wrlbr_info(unsigned int idx, u64 val) { wrmsrl(x86_pmu.lbr_info + idx, val); } static __always_inline u64 rdlbr_from(unsigned int idx, struct lbr_entry *lbr) { u64 val; if (lbr) return lbr->from; rdmsrl(x86_pmu.lbr_from + idx, val); return lbr_from_signext_quirk_rd(val); } static __always_inline u64 rdlbr_to(unsigned int idx, struct lbr_entry *lbr) { u64 val; if (lbr) return lbr->to; rdmsrl(x86_pmu.lbr_to + idx, val); return val; } static __always_inline u64 rdlbr_info(unsigned int idx, struct lbr_entry *lbr) { u64 val; if (lbr) return lbr->info; rdmsrl(x86_pmu.lbr_info + idx, val); return val; } static inline void wrlbr_all(struct lbr_entry *lbr, unsigned int idx, bool need_info) { wrlbr_from(idx, lbr->from); wrlbr_to(idx, lbr->to); if (need_info) wrlbr_info(idx, lbr->info); } static inline bool rdlbr_all(struct lbr_entry *lbr, unsigned int idx, bool need_info) { u64 from = rdlbr_from(idx, NULL); /* Don't read invalid entry */ if (!from) return false; lbr->from = from; lbr->to = rdlbr_to(idx, NULL); if (need_info) lbr->info = rdlbr_info(idx, NULL); return true; } void intel_pmu_lbr_restore(void *ctx) { struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); struct x86_perf_task_context *task_ctx = ctx; bool need_info = x86_pmu.lbr_has_info; u64 tos = task_ctx->tos; unsigned lbr_idx, mask; int i; mask = x86_pmu.lbr_nr - 1; for (i = 0; i < task_ctx->valid_lbrs; i++) { lbr_idx = (tos - i) & mask; wrlbr_all(&task_ctx->lbr[i], lbr_idx, need_info); } for (; i < x86_pmu.lbr_nr; i++) { lbr_idx = (tos - i) & mask; wrlbr_from(lbr_idx, 0); wrlbr_to(lbr_idx, 0); if (need_info) wrlbr_info(lbr_idx, 0); } wrmsrl(x86_pmu.lbr_tos, tos); if (cpuc->lbr_select) wrmsrl(MSR_LBR_SELECT, task_ctx->lbr_sel); } static void intel_pmu_arch_lbr_restore(void *ctx) { struct x86_perf_task_context_arch_lbr *task_ctx = ctx; struct lbr_entry *entries = task_ctx->entries; int i; /* Fast reset the LBRs before restore if the call stack is not full. */ if (!entries[x86_pmu.lbr_nr - 1].from) intel_pmu_arch_lbr_reset(); for (i = 0; i < x86_pmu.lbr_nr; i++) { if (!entries[i].from) break; wrlbr_all(&entries[i], i, true); } } /* * Restore the Architecture LBR state from the xsave area in the perf * context data for the task via the XRSTORS instruction. */ static void intel_pmu_arch_lbr_xrstors(void *ctx) { struct x86_perf_task_context_arch_lbr_xsave *task_ctx = ctx; xrstors(&task_ctx->xsave, XFEATURE_MASK_LBR); } static __always_inline bool lbr_is_reset_in_cstate(void *ctx) { if (static_cpu_has(X86_FEATURE_ARCH_LBR)) return x86_pmu.lbr_deep_c_reset && !rdlbr_from(0, NULL); return !rdlbr_from(((struct x86_perf_task_context *)ctx)->tos, NULL); } static void __intel_pmu_lbr_restore(void *ctx) { struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); if (task_context_opt(ctx)->lbr_callstack_users == 0 || task_context_opt(ctx)->lbr_stack_state == LBR_NONE) { intel_pmu_lbr_reset(); return; } /* * Does not restore the LBR registers, if * - No one else touched them, and * - Was not cleared in Cstate */ if ((ctx == cpuc->last_task_ctx) && (task_context_opt(ctx)->log_id == cpuc->last_log_id) && !lbr_is_reset_in_cstate(ctx)) { task_context_opt(ctx)->lbr_stack_state = LBR_NONE; return; } x86_pmu.lbr_restore(ctx); task_context_opt(ctx)->lbr_stack_state = LBR_NONE; } void intel_pmu_lbr_save(void *ctx) { struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); struct x86_perf_task_context *task_ctx = ctx; bool need_info = x86_pmu.lbr_has_info; unsigned lbr_idx, mask; u64 tos; int i; mask = x86_pmu.lbr_nr - 1; tos = intel_pmu_lbr_tos(); for (i = 0; i < x86_pmu.lbr_nr; i++) { lbr_idx = (tos - i) & mask; if (!rdlbr_all(&task_ctx->lbr[i], lbr_idx, need_info)) break; } task_ctx->valid_lbrs = i; task_ctx->tos = tos; if (cpuc->lbr_select) rdmsrl(MSR_LBR_SELECT, task_ctx->lbr_sel); } static void intel_pmu_arch_lbr_save(void *ctx) { struct x86_perf_task_context_arch_lbr *task_ctx = ctx; struct lbr_entry *entries = task_ctx->entries; int i; for (i = 0; i < x86_pmu.lbr_nr; i++) { if (!rdlbr_all(&entries[i], i, true)) break; } /* LBR call stack is not full. Reset is required in restore. */ if (i < x86_pmu.lbr_nr) entries[x86_pmu.lbr_nr - 1].from = 0; } /* * Save the Architecture LBR state to the xsave area in the perf * context data for the task via the XSAVES instruction. */ static void intel_pmu_arch_lbr_xsaves(void *ctx) { struct x86_perf_task_context_arch_lbr_xsave *task_ctx = ctx; xsaves(&task_ctx->xsave, XFEATURE_MASK_LBR); } static void __intel_pmu_lbr_save(void *ctx) { struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); if (task_context_opt(ctx)->lbr_callstack_users == 0) { task_context_opt(ctx)->lbr_stack_state = LBR_NONE; return; } x86_pmu.lbr_save(ctx); task_context_opt(ctx)->lbr_stack_state = LBR_VALID; cpuc->last_task_ctx = ctx; cpuc->last_log_id = ++task_context_opt(ctx)->log_id; } void intel_pmu_lbr_swap_task_ctx(struct perf_event_context *prev, struct perf_event_context *next) { void *prev_ctx_data, *next_ctx_data; swap(prev->task_ctx_data, next->task_ctx_data); /* * Architecture specific synchronization makes sense in * case both prev->task_ctx_data and next->task_ctx_data * pointers are allocated. */ prev_ctx_data = next->task_ctx_data; next_ctx_data = prev->task_ctx_data; if (!prev_ctx_data || !next_ctx_data) return; swap(task_context_opt(prev_ctx_data)->lbr_callstack_users, task_context_opt(next_ctx_data)->lbr_callstack_users); } void intel_pmu_lbr_sched_task(struct perf_event_context *ctx, bool sched_in) { struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); void *task_ctx; if (!cpuc->lbr_users) return; /* * If LBR callstack feature is enabled and the stack was saved when * the task was scheduled out, restore the stack. Otherwise flush * the LBR stack. */ task_ctx = ctx ? ctx->task_ctx_data : NULL; if (task_ctx) { if (sched_in) __intel_pmu_lbr_restore(task_ctx); else __intel_pmu_lbr_save(task_ctx); return; } /* * Since a context switch can flip the address space and LBR entries * are not tagged with an identifier, we need to wipe the LBR, even for * per-cpu events. You simply cannot resolve the branches from the old * address space. */ if (sched_in) intel_pmu_lbr_reset(); } static inline bool branch_user_callstack(unsigned br_sel) { return (br_sel & X86_BR_USER) && (br_sel & X86_BR_CALL_STACK); } void intel_pmu_lbr_add(struct perf_event *event) { struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); if (!x86_pmu.lbr_nr) return; if (event->hw.flags & PERF_X86_EVENT_LBR_SELECT) cpuc->lbr_select = 1; cpuc->br_sel = event->hw.branch_reg.reg; if (branch_user_callstack(cpuc->br_sel) && event->ctx->task_ctx_data) task_context_opt(event->ctx->task_ctx_data)->lbr_callstack_users++; /* * Request pmu::sched_task() callback, which will fire inside the * regular perf event scheduling, so that call will: * * - restore or wipe; when LBR-callstack, * - wipe; otherwise, * * when this is from __perf_event_task_sched_in(). * * However, if this is from perf_install_in_context(), no such callback * will follow and we'll need to reset the LBR here if this is the * first LBR event. * * The problem is, we cannot tell these cases apart... but we can * exclude the biggest chunk of cases by looking at * event->total_time_running. An event that has accrued runtime cannot * be 'new'. Conversely, a new event can get installed through the * context switch path for the first time. */ if (x86_pmu.intel_cap.pebs_baseline && event->attr.precise_ip > 0) cpuc->lbr_pebs_users++; perf_sched_cb_inc(event->ctx->pmu); if (!cpuc->lbr_users++ && !event->total_time_running) intel_pmu_lbr_reset(); } void release_lbr_buffers(void) { struct kmem_cache *kmem_cache; struct cpu_hw_events *cpuc; int cpu; if (!static_cpu_has(X86_FEATURE_ARCH_LBR)) return; for_each_possible_cpu(cpu) { cpuc = per_cpu_ptr(&cpu_hw_events, cpu); kmem_cache = x86_get_pmu(cpu)->task_ctx_cache; if (kmem_cache && cpuc->lbr_xsave) { kmem_cache_free(kmem_cache, cpuc->lbr_xsave); cpuc->lbr_xsave = NULL; } } } void reserve_lbr_buffers(void) { struct kmem_cache *kmem_cache; struct cpu_hw_events *cpuc; int cpu; if (!static_cpu_has(X86_FEATURE_ARCH_LBR)) return; for_each_possible_cpu(cpu) { cpuc = per_cpu_ptr(&cpu_hw_events, cpu); kmem_cache = x86_get_pmu(cpu)->task_ctx_cache; if (!kmem_cache || cpuc->lbr_xsave) continue; cpuc->lbr_xsave = kmem_cache_alloc_node(kmem_cache, GFP_KERNEL | __GFP_ZERO, cpu_to_node(cpu)); } } void intel_pmu_lbr_del(struct perf_event *event) { struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); if (!x86_pmu.lbr_nr) return; if (branch_user_callstack(cpuc->br_sel) && event->ctx->task_ctx_data) task_context_opt(event->ctx->task_ctx_data)->lbr_callstack_users--; if (event->hw.flags & PERF_X86_EVENT_LBR_SELECT) cpuc->lbr_select = 0; if (x86_pmu.intel_cap.pebs_baseline && event->attr.precise_ip > 0) cpuc->lbr_pebs_users--; cpuc->lbr_users--; WARN_ON_ONCE(cpuc->lbr_users < 0); WARN_ON_ONCE(cpuc->lbr_pebs_users < 0); perf_sched_cb_dec(event->ctx->pmu); } static inline bool vlbr_exclude_host(void) { struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); return test_bit(INTEL_PMC_IDX_FIXED_VLBR, (unsigned long *)&cpuc->intel_ctrl_guest_mask); } void intel_pmu_lbr_enable_all(bool pmi) { struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); if (cpuc->lbr_users && !vlbr_exclude_host()) __intel_pmu_lbr_enable(pmi); } void intel_pmu_lbr_disable_all(void) { struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); if (cpuc->lbr_users && !vlbr_exclude_host()) { if (static_cpu_has(X86_FEATURE_ARCH_LBR)) return __intel_pmu_arch_lbr_disable(); __intel_pmu_lbr_disable(); } } void intel_pmu_lbr_read_32(struct cpu_hw_events *cpuc) { unsigned long mask = x86_pmu.lbr_nr - 1; struct perf_branch_entry *br = cpuc->lbr_entries; u64 tos = intel_pmu_lbr_tos(); int i; for (i = 0; i < x86_pmu.lbr_nr; i++) { unsigned long lbr_idx = (tos - i) & mask; union { struct { u32 from; u32 to; }; u64 lbr; } msr_lastbranch; rdmsrl(x86_pmu.lbr_from + lbr_idx, msr_lastbranch.lbr); perf_clear_branch_entry_bitfields(br); br->from = msr_lastbranch.from; br->to = msr_lastbranch.to; br++; } cpuc->lbr_stack.nr = i; cpuc->lbr_stack.hw_idx = tos; } /* * Due to lack of segmentation in Linux the effective address (offset) * is the same as the linear address, allowing us to merge the LIP and EIP * LBR formats. */ void intel_pmu_lbr_read_64(struct cpu_hw_events *cpuc) { bool need_info = false, call_stack = false; unsigned long mask = x86_pmu.lbr_nr - 1; struct perf_branch_entry *br = cpuc->lbr_entries; u64 tos = intel_pmu_lbr_tos(); int i; int out = 0; int num = x86_pmu.lbr_nr; if (cpuc->lbr_sel) { need_info = !(cpuc->lbr_sel->config & LBR_NO_INFO); if (cpuc->lbr_sel->config & LBR_CALL_STACK) call_stack = true; } for (i = 0; i < num; i++) { unsigned long lbr_idx = (tos - i) & mask; u64 from, to, mis = 0, pred = 0, in_tx = 0, abort = 0; u16 cycles = 0; from = rdlbr_from(lbr_idx, NULL); to = rdlbr_to(lbr_idx, NULL); /* * Read LBR call stack entries * until invalid entry (0s) is detected. */ if (call_stack && !from) break; if (x86_pmu.lbr_has_info) { if (need_info) { u64 info; info = rdlbr_info(lbr_idx, NULL); mis = !!(info & LBR_INFO_MISPRED); pred = !mis; cycles = (info & LBR_INFO_CYCLES); if (x86_pmu.lbr_has_tsx) { in_tx = !!(info & LBR_INFO_IN_TX); abort = !!(info & LBR_INFO_ABORT); } } } else { int skip = 0; if (x86_pmu.lbr_from_flags) { mis = !!(from & LBR_FROM_FLAG_MISPRED); pred = !mis; skip = 1; } if (x86_pmu.lbr_has_tsx) { in_tx = !!(from & LBR_FROM_FLAG_IN_TX); abort = !!(from & LBR_FROM_FLAG_ABORT); skip = 3; } from = (u64)((((s64)from) << skip) >> skip); if (x86_pmu.lbr_to_cycles) { cycles = ((to >> 48) & LBR_INFO_CYCLES); to = (u64)((((s64)to) << 16) >> 16); } } /* * Some CPUs report duplicated abort records, * with the second entry not having an abort bit set. * Skip them here. This loop runs backwards, * so we need to undo the previous record. * If the abort just happened outside the window * the extra entry cannot be removed. */ if (abort && x86_pmu.lbr_double_abort && out > 0) out--; perf_clear_branch_entry_bitfields(br+out); br[out].from = from; br[out].to = to; br[out].mispred = mis; br[out].predicted = pred; br[out].in_tx = in_tx; br[out].abort = abort; br[out].cycles = cycles; out++; } cpuc->lbr_stack.nr = out; cpuc->lbr_stack.hw_idx = tos; } static DEFINE_STATIC_KEY_FALSE(x86_lbr_mispred); static DEFINE_STATIC_KEY_FALSE(x86_lbr_cycles); static DEFINE_STATIC_KEY_FALSE(x86_lbr_type); static __always_inline int get_lbr_br_type(u64 info) { int type = 0; if (static_branch_likely(&x86_lbr_type)) type = (info & LBR_INFO_BR_TYPE) >> LBR_INFO_BR_TYPE_OFFSET; return type; } static __always_inline bool get_lbr_mispred(u64 info) { bool mispred = 0; if (static_branch_likely(&x86_lbr_mispred)) mispred = !!(info & LBR_INFO_MISPRED); return mispred; } static __always_inline u16 get_lbr_cycles(u64 info) { u16 cycles = info & LBR_INFO_CYCLES; if (static_cpu_has(X86_FEATURE_ARCH_LBR) && (!static_branch_likely(&x86_lbr_cycles) || !(info & LBR_INFO_CYC_CNT_VALID))) cycles = 0; return cycles; } static void intel_pmu_store_lbr(struct cpu_hw_events *cpuc, struct lbr_entry *entries) { struct perf_branch_entry *e; struct lbr_entry *lbr; u64 from, to, info; int i; for (i = 0; i < x86_pmu.lbr_nr; i++) { lbr = entries ? &entries[i] : NULL; e = &cpuc->lbr_entries[i]; from = rdlbr_from(i, lbr); /* * Read LBR entries until invalid entry (0s) is detected. */ if (!from) break; to = rdlbr_to(i, lbr); info = rdlbr_info(i, lbr); perf_clear_branch_entry_bitfields(e); e->from = from; e->to = to; e->mispred = get_lbr_mispred(info); e->predicted = !e->mispred; e->in_tx = !!(info & LBR_INFO_IN_TX); e->abort = !!(info & LBR_INFO_ABORT); e->cycles = get_lbr_cycles(info); e->type = get_lbr_br_type(info); } cpuc->lbr_stack.nr = i; } static void intel_pmu_arch_lbr_read(struct cpu_hw_events *cpuc) { intel_pmu_store_lbr(cpuc, NULL); } static void intel_pmu_arch_lbr_read_xsave(struct cpu_hw_events *cpuc) { struct x86_perf_task_context_arch_lbr_xsave *xsave = cpuc->lbr_xsave; if (!xsave) { intel_pmu_store_lbr(cpuc, NULL); return; } xsaves(&xsave->xsave, XFEATURE_MASK_LBR); intel_pmu_store_lbr(cpuc, xsave->lbr.entries); } void intel_pmu_lbr_read(void) { struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); /* * Don't read when all LBRs users are using adaptive PEBS. * * This could be smarter and actually check the event, * but this simple approach seems to work for now. */ if (!cpuc->lbr_users || vlbr_exclude_host() || cpuc->lbr_users == cpuc->lbr_pebs_users) return; x86_pmu.lbr_read(cpuc); intel_pmu_lbr_filter(cpuc); } /* * SW filter is used: * - in case there is no HW filter * - in case the HW filter has errata or limitations */ static int intel_pmu_setup_sw_lbr_filter(struct perf_event *event) { u64 br_type = event->attr.branch_sample_type; int mask = 0; if (br_type & PERF_SAMPLE_BRANCH_USER) mask |= X86_BR_USER; if (br_type & PERF_SAMPLE_BRANCH_KERNEL) mask |= X86_BR_KERNEL; /* we ignore BRANCH_HV here */ if (br_type & PERF_SAMPLE_BRANCH_ANY) mask |= X86_BR_ANY; if (br_type & PERF_SAMPLE_BRANCH_ANY_CALL) mask |= X86_BR_ANY_CALL; if (br_type & PERF_SAMPLE_BRANCH_ANY_RETURN) mask |= X86_BR_RET | X86_BR_IRET | X86_BR_SYSRET; if (br_type & PERF_SAMPLE_BRANCH_IND_CALL) mask |= X86_BR_IND_CALL; if (br_type & PERF_SAMPLE_BRANCH_ABORT_TX) mask |= X86_BR_ABORT; if (br_type & PERF_SAMPLE_BRANCH_IN_TX) mask |= X86_BR_IN_TX; if (br_type & PERF_SAMPLE_BRANCH_NO_TX) mask |= X86_BR_NO_TX; if (br_type & PERF_SAMPLE_BRANCH_COND) mask |= X86_BR_JCC; if (br_type & PERF_SAMPLE_BRANCH_CALL_STACK) { if (!x86_pmu_has_lbr_callstack()) return -EOPNOTSUPP; if (mask & ~(X86_BR_USER | X86_BR_KERNEL)) return -EINVAL; mask |= X86_BR_CALL | X86_BR_IND_CALL | X86_BR_RET | X86_BR_CALL_STACK; } if (br_type & PERF_SAMPLE_BRANCH_IND_JUMP) mask |= X86_BR_IND_JMP; if (br_type & PERF_SAMPLE_BRANCH_CALL) mask |= X86_BR_CALL | X86_BR_ZERO_CALL; if (br_type & PERF_SAMPLE_BRANCH_TYPE_SAVE) mask |= X86_BR_TYPE_SAVE; /* * stash actual user request into reg, it may * be used by fixup code for some CPU */ event->hw.branch_reg.reg = mask; return 0; } /* * setup the HW LBR filter * Used only when available, may not be enough to disambiguate * all branches, may need the help of the SW filter */ static int intel_pmu_setup_hw_lbr_filter(struct perf_event *event) { struct hw_perf_event_extra *reg; u64 br_type = event->attr.branch_sample_type; u64 mask = 0, v; int i; for (i = 0; i < PERF_SAMPLE_BRANCH_MAX_SHIFT; i++) { if (!(br_type & (1ULL << i))) continue; v = x86_pmu.lbr_sel_map[i]; if (v == LBR_NOT_SUPP) return -EOPNOTSUPP; if (v != LBR_IGN) mask |= v; } reg = &event->hw.branch_reg; reg->idx = EXTRA_REG_LBR; if (static_cpu_has(X86_FEATURE_ARCH_LBR)) { reg->config = mask; /* * The Arch LBR HW can retrieve the common branch types * from the LBR_INFO. It doesn't require the high overhead * SW disassemble. * Enable the branch type by default for the Arch LBR. */ reg->reg |= X86_BR_TYPE_SAVE; return 0; } /* * The first 9 bits (LBR_SEL_MASK) in LBR_SELECT operate * in suppress mode. So LBR_SELECT should be set to * (~mask & LBR_SEL_MASK) | (mask & ~LBR_SEL_MASK) * But the 10th bit LBR_CALL_STACK does not operate * in suppress mode. */ reg->config = mask ^ (x86_pmu.lbr_sel_mask & ~LBR_CALL_STACK); if ((br_type & PERF_SAMPLE_BRANCH_NO_CYCLES) && (br_type & PERF_SAMPLE_BRANCH_NO_FLAGS) && x86_pmu.lbr_has_info) reg->config |= LBR_NO_INFO; return 0; } int intel_pmu_setup_lbr_filter(struct perf_event *event) { int ret = 0; /* * no LBR on this PMU */ if (!x86_pmu.lbr_nr) return -EOPNOTSUPP; /* * setup SW LBR filter */ ret = intel_pmu_setup_sw_lbr_filter(event); if (ret) return ret; /* * setup HW LBR filter, if any */ if (x86_pmu.lbr_sel_map) ret = intel_pmu_setup_hw_lbr_filter(event); return ret; } /* * return the type of control flow change at address "from" * instruction is not necessarily a branch (in case of interrupt). * * The branch type returned also includes the priv level of the * target of the control flow change (X86_BR_USER, X86_BR_KERNEL). * * If a branch type is unknown OR the instruction cannot be * decoded (e.g., text page not present), then X86_BR_NONE is * returned. */ static int branch_type(unsigned long from, unsigned long to, int abort) { struct insn insn; void *addr; int bytes_read, bytes_left; int ret = X86_BR_NONE; int ext, to_plm, from_plm; u8 buf[MAX_INSN_SIZE]; int is64 = 0; to_plm = kernel_ip(to) ? X86_BR_KERNEL : X86_BR_USER; from_plm = kernel_ip(from) ? X86_BR_KERNEL : X86_BR_USER; /* * maybe zero if lbr did not fill up after a reset by the time * we get a PMU interrupt */ if (from == 0 || to == 0) return X86_BR_NONE; if (abort) return X86_BR_ABORT | to_plm; if (from_plm == X86_BR_USER) { /* * can happen if measuring at the user level only * and we interrupt in a kernel thread, e.g., idle. */ if (!current->mm) return X86_BR_NONE; /* may fail if text not present */ bytes_left = copy_from_user_nmi(buf, (void __user *)from, MAX_INSN_SIZE); bytes_read = MAX_INSN_SIZE - bytes_left; if (!bytes_read) return X86_BR_NONE; addr = buf; } else { /* * The LBR logs any address in the IP, even if the IP just * faulted. This means userspace can control the from address. * Ensure we don't blindly read any address by validating it is * a known text address. */ if (kernel_text_address(from)) { addr = (void *)from; /* * Assume we can get the maximum possible size * when grabbing kernel data. This is not * _strictly_ true since we could possibly be * executing up next to a memory hole, but * it is very unlikely to be a problem. */ bytes_read = MAX_INSN_SIZE; } else { return X86_BR_NONE; } } /* * decoder needs to know the ABI especially * on 64-bit systems running 32-bit apps */ #ifdef CONFIG_X86_64 is64 = kernel_ip((unsigned long)addr) || any_64bit_mode(current_pt_regs()); #endif insn_init(&insn, addr, bytes_read, is64); if (insn_get_opcode(&insn)) return X86_BR_ABORT; switch (insn.opcode.bytes[0]) { case 0xf: switch (insn.opcode.bytes[1]) { case 0x05: /* syscall */ case 0x34: /* sysenter */ ret = X86_BR_SYSCALL; break; case 0x07: /* sysret */ case 0x35: /* sysexit */ ret = X86_BR_SYSRET; break; case 0x80 ... 0x8f: /* conditional */ ret = X86_BR_JCC; break; default: ret = X86_BR_NONE; } break; case 0x70 ... 0x7f: /* conditional */ ret = X86_BR_JCC; break; case 0xc2: /* near ret */ case 0xc3: /* near ret */ case 0xca: /* far ret */ case 0xcb: /* far ret */ ret = X86_BR_RET; break; case 0xcf: /* iret */ ret = X86_BR_IRET; break; case 0xcc ... 0xce: /* int */ ret = X86_BR_INT; break; case 0xe8: /* call near rel */ if (insn_get_immediate(&insn) || insn.immediate1.value == 0) { /* zero length call */ ret = X86_BR_ZERO_CALL; break; } fallthrough; case 0x9a: /* call far absolute */ ret = X86_BR_CALL; break; case 0xe0 ... 0xe3: /* loop jmp */ ret = X86_BR_JCC; break; case 0xe9 ... 0xeb: /* jmp */ ret = X86_BR_JMP; break; case 0xff: /* call near absolute, call far absolute ind */ if (insn_get_modrm(&insn)) return X86_BR_ABORT; ext = (insn.modrm.bytes[0] >> 3) & 0x7; switch (ext) { case 2: /* near ind call */ case 3: /* far ind call */ ret = X86_BR_IND_CALL; break; case 4: case 5: ret = X86_BR_IND_JMP; break; } break; default: ret = X86_BR_NONE; } /* * interrupts, traps, faults (and thus ring transition) may * occur on any instructions. Thus, to classify them correctly, * we need to first look at the from and to priv levels. If they * are different and to is in the kernel, then it indicates * a ring transition. If the from instruction is not a ring * transition instr (syscall, systenter, int), then it means * it was a irq, trap or fault. * * we have no way of detecting kernel to kernel faults. */ if (from_plm == X86_BR_USER && to_plm == X86_BR_KERNEL && ret != X86_BR_SYSCALL && ret != X86_BR_INT) ret = X86_BR_IRQ; /* * branch priv level determined by target as * is done by HW when LBR_SELECT is implemented */ if (ret != X86_BR_NONE) ret |= to_plm; return ret; } #define X86_BR_TYPE_MAP_MAX 16 static int branch_map[X86_BR_TYPE_MAP_MAX] = { PERF_BR_CALL, /* X86_BR_CALL */ PERF_BR_RET, /* X86_BR_RET */ PERF_BR_SYSCALL, /* X86_BR_SYSCALL */ PERF_BR_SYSRET, /* X86_BR_SYSRET */ PERF_BR_UNKNOWN, /* X86_BR_INT */ PERF_BR_ERET, /* X86_BR_IRET */ PERF_BR_COND, /* X86_BR_JCC */ PERF_BR_UNCOND, /* X86_BR_JMP */ PERF_BR_IRQ, /* X86_BR_IRQ */ PERF_BR_IND_CALL, /* X86_BR_IND_CALL */ PERF_BR_UNKNOWN, /* X86_BR_ABORT */ PERF_BR_UNKNOWN, /* X86_BR_IN_TX */ PERF_BR_UNKNOWN, /* X86_BR_NO_TX */ PERF_BR_CALL, /* X86_BR_ZERO_CALL */ PERF_BR_UNKNOWN, /* X86_BR_CALL_STACK */ PERF_BR_IND, /* X86_BR_IND_JMP */ }; static int common_branch_type(int type) { int i; type >>= 2; /* skip X86_BR_USER and X86_BR_KERNEL */ if (type) { i = __ffs(type); if (i < X86_BR_TYPE_MAP_MAX) return branch_map[i]; } return PERF_BR_UNKNOWN; } enum { ARCH_LBR_BR_TYPE_JCC = 0, ARCH_LBR_BR_TYPE_NEAR_IND_JMP = 1, ARCH_LBR_BR_TYPE_NEAR_REL_JMP = 2, ARCH_LBR_BR_TYPE_NEAR_IND_CALL = 3, ARCH_LBR_BR_TYPE_NEAR_REL_CALL = 4, ARCH_LBR_BR_TYPE_NEAR_RET = 5, ARCH_LBR_BR_TYPE_KNOWN_MAX = ARCH_LBR_BR_TYPE_NEAR_RET, ARCH_LBR_BR_TYPE_MAP_MAX = 16, }; static const int arch_lbr_br_type_map[ARCH_LBR_BR_TYPE_MAP_MAX] = { [ARCH_LBR_BR_TYPE_JCC] = X86_BR_JCC, [ARCH_LBR_BR_TYPE_NEAR_IND_JMP] = X86_BR_IND_JMP, [ARCH_LBR_BR_TYPE_NEAR_REL_JMP] = X86_BR_JMP, [ARCH_LBR_BR_TYPE_NEAR_IND_CALL] = X86_BR_IND_CALL, [ARCH_LBR_BR_TYPE_NEAR_REL_CALL] = X86_BR_CALL, [ARCH_LBR_BR_TYPE_NEAR_RET] = X86_BR_RET, }; /* * implement actual branch filter based on user demand. * Hardware may not exactly satisfy that request, thus * we need to inspect opcodes. Mismatched branches are * discarded. Therefore, the number of branches returned * in PERF_SAMPLE_BRANCH_STACK sample may vary. */ static void intel_pmu_lbr_filter(struct cpu_hw_events *cpuc) { u64 from, to; int br_sel = cpuc->br_sel; int i, j, type, to_plm; bool compress = false; /* if sampling all branches, then nothing to filter */ if (((br_sel & X86_BR_ALL) == X86_BR_ALL) && ((br_sel & X86_BR_TYPE_SAVE) != X86_BR_TYPE_SAVE)) return; for (i = 0; i < cpuc->lbr_stack.nr; i++) { from = cpuc->lbr_entries[i].from; to = cpuc->lbr_entries[i].to; type = cpuc->lbr_entries[i].type; /* * Parse the branch type recorded in LBR_x_INFO MSR. * Doesn't support OTHER_BRANCH decoding for now. * OTHER_BRANCH branch type still rely on software decoding. */ if (static_cpu_has(X86_FEATURE_ARCH_LBR) && type <= ARCH_LBR_BR_TYPE_KNOWN_MAX) { to_plm = kernel_ip(to) ? X86_BR_KERNEL : X86_BR_USER; type = arch_lbr_br_type_map[type] | to_plm; } else type = branch_type(from, to, cpuc->lbr_entries[i].abort); if (type != X86_BR_NONE && (br_sel & X86_BR_ANYTX)) { if (cpuc->lbr_entries[i].in_tx) type |= X86_BR_IN_TX; else type |= X86_BR_NO_TX; } /* if type does not correspond, then discard */ if (type == X86_BR_NONE || (br_sel & type) != type) { cpuc->lbr_entries[i].from = 0; compress = true; } if ((br_sel & X86_BR_TYPE_SAVE) == X86_BR_TYPE_SAVE) cpuc->lbr_entries[i].type = common_branch_type(type); } if (!compress) return; /* remove all entries with from=0 */ for (i = 0; i < cpuc->lbr_stack.nr; ) { if (!cpuc->lbr_entries[i].from) { j = i; while (++j < cpuc->lbr_stack.nr) cpuc->lbr_entries[j-1] = cpuc->lbr_entries[j]; cpuc->lbr_stack.nr--; if (!cpuc->lbr_entries[i].from) continue; } i++; } } void intel_pmu_store_pebs_lbrs(struct lbr_entry *lbr) { struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); /* Cannot get TOS for large PEBS and Arch LBR */ if (static_cpu_has(X86_FEATURE_ARCH_LBR) || (cpuc->n_pebs == cpuc->n_large_pebs)) cpuc->lbr_stack.hw_idx = -1ULL; else cpuc->lbr_stack.hw_idx = intel_pmu_lbr_tos(); intel_pmu_store_lbr(cpuc, lbr); intel_pmu_lbr_filter(cpuc); } /* * Map interface branch filters onto LBR filters */ static const int nhm_lbr_sel_map[PERF_SAMPLE_BRANCH_MAX_SHIFT] = { [PERF_SAMPLE_BRANCH_ANY_SHIFT] = LBR_ANY, [PERF_SAMPLE_BRANCH_USER_SHIFT] = LBR_USER, [PERF_SAMPLE_BRANCH_KERNEL_SHIFT] = LBR_KERNEL, [PERF_SAMPLE_BRANCH_HV_SHIFT] = LBR_IGN, [PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT] = LBR_RETURN | LBR_REL_JMP | LBR_IND_JMP | LBR_FAR, /* * NHM/WSM erratum: must include REL_JMP+IND_JMP to get CALL branches */ [PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT] = LBR_REL_CALL | LBR_IND_CALL | LBR_REL_JMP | LBR_IND_JMP | LBR_FAR, /* * NHM/WSM erratum: must include IND_JMP to capture IND_CALL */ [PERF_SAMPLE_BRANCH_IND_CALL_SHIFT] = LBR_IND_CALL | LBR_IND_JMP, [PERF_SAMPLE_BRANCH_COND_SHIFT] = LBR_JCC, [PERF_SAMPLE_BRANCH_IND_JUMP_SHIFT] = LBR_IND_JMP, }; static const int snb_lbr_sel_map[PERF_SAMPLE_BRANCH_MAX_SHIFT] = { [PERF_SAMPLE_BRANCH_ANY_SHIFT] = LBR_ANY, [PERF_SAMPLE_BRANCH_USER_SHIFT] = LBR_USER, [PERF_SAMPLE_BRANCH_KERNEL_SHIFT] = LBR_KERNEL, [PERF_SAMPLE_BRANCH_HV_SHIFT] = LBR_IGN, [PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT] = LBR_RETURN | LBR_FAR, [PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT] = LBR_REL_CALL | LBR_IND_CALL | LBR_FAR, [PERF_SAMPLE_BRANCH_IND_CALL_SHIFT] = LBR_IND_CALL, [PERF_SAMPLE_BRANCH_COND_SHIFT] = LBR_JCC, [PERF_SAMPLE_BRANCH_IND_JUMP_SHIFT] = LBR_IND_JMP, [PERF_SAMPLE_BRANCH_CALL_SHIFT] = LBR_REL_CALL, }; static const int hsw_lbr_sel_map[PERF_SAMPLE_BRANCH_MAX_SHIFT] = { [PERF_SAMPLE_BRANCH_ANY_SHIFT] = LBR_ANY, [PERF_SAMPLE_BRANCH_USER_SHIFT] = LBR_USER, [PERF_SAMPLE_BRANCH_KERNEL_SHIFT] = LBR_KERNEL, [PERF_SAMPLE_BRANCH_HV_SHIFT] = LBR_IGN, [PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT] = LBR_RETURN | LBR_FAR, [PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT] = LBR_REL_CALL | LBR_IND_CALL | LBR_FAR, [PERF_SAMPLE_BRANCH_IND_CALL_SHIFT] = LBR_IND_CALL, [PERF_SAMPLE_BRANCH_COND_SHIFT] = LBR_JCC, [PERF_SAMPLE_BRANCH_CALL_STACK_SHIFT] = LBR_REL_CALL | LBR_IND_CALL | LBR_RETURN | LBR_CALL_STACK, [PERF_SAMPLE_BRANCH_IND_JUMP_SHIFT] = LBR_IND_JMP, [PERF_SAMPLE_BRANCH_CALL_SHIFT] = LBR_REL_CALL, }; static int arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_MAX_SHIFT] = { [PERF_SAMPLE_BRANCH_ANY_SHIFT] = ARCH_LBR_ANY, [PERF_SAMPLE_BRANCH_USER_SHIFT] = ARCH_LBR_USER, [PERF_SAMPLE_BRANCH_KERNEL_SHIFT] = ARCH_LBR_KERNEL, [PERF_SAMPLE_BRANCH_HV_SHIFT] = LBR_IGN, [PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT] = ARCH_LBR_RETURN | ARCH_LBR_OTHER_BRANCH, [PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT] = ARCH_LBR_REL_CALL | ARCH_LBR_IND_CALL | ARCH_LBR_OTHER_BRANCH, [PERF_SAMPLE_BRANCH_IND_CALL_SHIFT] = ARCH_LBR_IND_CALL, [PERF_SAMPLE_BRANCH_COND_SHIFT] = ARCH_LBR_JCC, [PERF_SAMPLE_BRANCH_CALL_STACK_SHIFT] = ARCH_LBR_REL_CALL | ARCH_LBR_IND_CALL | ARCH_LBR_RETURN | ARCH_LBR_CALL_STACK, [PERF_SAMPLE_BRANCH_IND_JUMP_SHIFT] = ARCH_LBR_IND_JMP, [PERF_SAMPLE_BRANCH_CALL_SHIFT] = ARCH_LBR_REL_CALL, }; /* core */ void __init intel_pmu_lbr_init_core(void) { x86_pmu.lbr_nr = 4; x86_pmu.lbr_tos = MSR_LBR_TOS; x86_pmu.lbr_from = MSR_LBR_CORE_FROM; x86_pmu.lbr_to = MSR_LBR_CORE_TO; /* * SW branch filter usage: * - compensate for lack of HW filter */ } /* nehalem/westmere */ void __init intel_pmu_lbr_init_nhm(void) { x86_pmu.lbr_nr = 16; x86_pmu.lbr_tos = MSR_LBR_TOS; x86_pmu.lbr_from = MSR_LBR_NHM_FROM; x86_pmu.lbr_to = MSR_LBR_NHM_TO; x86_pmu.lbr_sel_mask = LBR_SEL_MASK; x86_pmu.lbr_sel_map = nhm_lbr_sel_map; /* * SW branch filter usage: * - workaround LBR_SEL errata (see above) * - support syscall, sysret capture. * That requires LBR_FAR but that means far * jmp need to be filtered out */ } /* sandy bridge */ void __init intel_pmu_lbr_init_snb(void) { x86_pmu.lbr_nr = 16; x86_pmu.lbr_tos = MSR_LBR_TOS; x86_pmu.lbr_from = MSR_LBR_NHM_FROM; x86_pmu.lbr_to = MSR_LBR_NHM_TO; x86_pmu.lbr_sel_mask = LBR_SEL_MASK; x86_pmu.lbr_sel_map = snb_lbr_sel_map; /* * SW branch filter usage: * - support syscall, sysret capture. * That requires LBR_FAR but that means far * jmp need to be filtered out */ } static inline struct kmem_cache * create_lbr_kmem_cache(size_t size, size_t align) { return kmem_cache_create("x86_lbr", size, align, 0, NULL); } /* haswell */ void intel_pmu_lbr_init_hsw(void) { size_t size = sizeof(struct x86_perf_task_context); x86_pmu.lbr_nr = 16; x86_pmu.lbr_tos = MSR_LBR_TOS; x86_pmu.lbr_from = MSR_LBR_NHM_FROM; x86_pmu.lbr_to = MSR_LBR_NHM_TO; x86_pmu.lbr_sel_mask = LBR_SEL_MASK; x86_pmu.lbr_sel_map = hsw_lbr_sel_map; x86_get_pmu(smp_processor_id())->task_ctx_cache = create_lbr_kmem_cache(size, 0); } /* skylake */ __init void intel_pmu_lbr_init_skl(void) { size_t size = sizeof(struct x86_perf_task_context); x86_pmu.lbr_nr = 32; x86_pmu.lbr_tos = MSR_LBR_TOS; x86_pmu.lbr_from = MSR_LBR_NHM_FROM; x86_pmu.lbr_to = MSR_LBR_NHM_TO; x86_pmu.lbr_info = MSR_LBR_INFO_0; x86_pmu.lbr_sel_mask = LBR_SEL_MASK; x86_pmu.lbr_sel_map = hsw_lbr_sel_map; x86_get_pmu(smp_processor_id())->task_ctx_cache = create_lbr_kmem_cache(size, 0); /* * SW branch filter usage: * - support syscall, sysret capture. * That requires LBR_FAR but that means far * jmp need to be filtered out */ } /* atom */ void __init intel_pmu_lbr_init_atom(void) { /* * only models starting at stepping 10 seems * to have an operational LBR which can freeze * on PMU interrupt */ if (boot_cpu_data.x86_model == 28 && boot_cpu_data.x86_stepping < 10) { pr_cont("LBR disabled due to erratum"); return; } x86_pmu.lbr_nr = 8; x86_pmu.lbr_tos = MSR_LBR_TOS; x86_pmu.lbr_from = MSR_LBR_CORE_FROM; x86_pmu.lbr_to = MSR_LBR_CORE_TO; /* * SW branch filter usage: * - compensate for lack of HW filter */ } /* slm */ void __init intel_pmu_lbr_init_slm(void) { x86_pmu.lbr_nr = 8; x86_pmu.lbr_tos = MSR_LBR_TOS; x86_pmu.lbr_from = MSR_LBR_CORE_FROM; x86_pmu.lbr_to = MSR_LBR_CORE_TO; x86_pmu.lbr_sel_mask = LBR_SEL_MASK; x86_pmu.lbr_sel_map = nhm_lbr_sel_map; /* * SW branch filter usage: * - compensate for lack of HW filter */ pr_cont("8-deep LBR, "); } /* Knights Landing */ void intel_pmu_lbr_init_knl(void) { x86_pmu.lbr_nr = 8; x86_pmu.lbr_tos = MSR_LBR_TOS; x86_pmu.lbr_from = MSR_LBR_NHM_FROM; x86_pmu.lbr_to = MSR_LBR_NHM_TO; x86_pmu.lbr_sel_mask = LBR_SEL_MASK; x86_pmu.lbr_sel_map = snb_lbr_sel_map; /* Knights Landing does have MISPREDICT bit */ if (x86_pmu.intel_cap.lbr_format == LBR_FORMAT_LIP) x86_pmu.intel_cap.lbr_format = LBR_FORMAT_EIP_FLAGS; } void intel_pmu_lbr_init(void) { switch (x86_pmu.intel_cap.lbr_format) { case LBR_FORMAT_EIP_FLAGS2: x86_pmu.lbr_has_tsx = 1; x86_pmu.lbr_from_flags = 1; if (lbr_from_signext_quirk_needed()) static_branch_enable(&lbr_from_quirk_key); break; case LBR_FORMAT_EIP_FLAGS: x86_pmu.lbr_from_flags = 1; break; case LBR_FORMAT_INFO: x86_pmu.lbr_has_tsx = 1; fallthrough; case LBR_FORMAT_INFO2: x86_pmu.lbr_has_info = 1; break; case LBR_FORMAT_TIME: x86_pmu.lbr_from_flags = 1; x86_pmu.lbr_to_cycles = 1; break; } if (x86_pmu.lbr_has_info) { /* * Only used in combination with baseline pebs. */ static_branch_enable(&x86_lbr_mispred); static_branch_enable(&x86_lbr_cycles); } } /* * LBR state size is variable based on the max number of registers. * This calculates the expected state size, which should match * what the hardware enumerates for the size of XFEATURE_LBR. */ static inline unsigned int get_lbr_state_size(void) { return sizeof(struct arch_lbr_state) + x86_pmu.lbr_nr * sizeof(struct lbr_entry); } static bool is_arch_lbr_xsave_available(void) { if (!boot_cpu_has(X86_FEATURE_XSAVES)) return false; /* * Check the LBR state with the corresponding software structure. * Disable LBR XSAVES support if the size doesn't match. */ if (xfeature_size(XFEATURE_LBR) == 0) return false; if (WARN_ON(xfeature_size(XFEATURE_LBR) != get_lbr_state_size())) return false; return true; } void __init intel_pmu_arch_lbr_init(void) { struct pmu *pmu = x86_get_pmu(smp_processor_id()); union cpuid28_eax eax; union cpuid28_ebx ebx; union cpuid28_ecx ecx; unsigned int unused_edx; bool arch_lbr_xsave; size_t size; u64 lbr_nr; /* Arch LBR Capabilities */ cpuid(28, &eax.full, &ebx.full, &ecx.full, &unused_edx); lbr_nr = fls(eax.split.lbr_depth_mask) * 8; if (!lbr_nr) goto clear_arch_lbr; /* Apply the max depth of Arch LBR */ if (wrmsrl_safe(MSR_ARCH_LBR_DEPTH, lbr_nr)) goto clear_arch_lbr; x86_pmu.lbr_depth_mask = eax.split.lbr_depth_mask; x86_pmu.lbr_deep_c_reset = eax.split.lbr_deep_c_reset; x86_pmu.lbr_lip = eax.split.lbr_lip; x86_pmu.lbr_cpl = ebx.split.lbr_cpl; x86_pmu.lbr_filter = ebx.split.lbr_filter; x86_pmu.lbr_call_stack = ebx.split.lbr_call_stack; x86_pmu.lbr_mispred = ecx.split.lbr_mispred; x86_pmu.lbr_timed_lbr = ecx.split.lbr_timed_lbr; x86_pmu.lbr_br_type = ecx.split.lbr_br_type; x86_pmu.lbr_nr = lbr_nr; if (x86_pmu.lbr_mispred) static_branch_enable(&x86_lbr_mispred); if (x86_pmu.lbr_timed_lbr) static_branch_enable(&x86_lbr_cycles); if (x86_pmu.lbr_br_type) static_branch_enable(&x86_lbr_type); arch_lbr_xsave = is_arch_lbr_xsave_available(); if (arch_lbr_xsave) { size = sizeof(struct x86_perf_task_context_arch_lbr_xsave) + get_lbr_state_size(); pmu->task_ctx_cache = create_lbr_kmem_cache(size, XSAVE_ALIGNMENT); } if (!pmu->task_ctx_cache) { arch_lbr_xsave = false; size = sizeof(struct x86_perf_task_context_arch_lbr) + lbr_nr * sizeof(struct lbr_entry); pmu->task_ctx_cache = create_lbr_kmem_cache(size, 0); } x86_pmu.lbr_from = MSR_ARCH_LBR_FROM_0; x86_pmu.lbr_to = MSR_ARCH_LBR_TO_0; x86_pmu.lbr_info = MSR_ARCH_LBR_INFO_0; /* LBR callstack requires both CPL and Branch Filtering support */ if (!x86_pmu.lbr_cpl || !x86_pmu.lbr_filter || !x86_pmu.lbr_call_stack) arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_CALL_STACK_SHIFT] = LBR_NOT_SUPP; if (!x86_pmu.lbr_cpl) { arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_USER_SHIFT] = LBR_NOT_SUPP; arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_KERNEL_SHIFT] = LBR_NOT_SUPP; } else if (!x86_pmu.lbr_filter) { arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_ANY_SHIFT] = LBR_NOT_SUPP; arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT] = LBR_NOT_SUPP; arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT] = LBR_NOT_SUPP; arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_IND_CALL_SHIFT] = LBR_NOT_SUPP; arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_COND_SHIFT] = LBR_NOT_SUPP; arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_IND_JUMP_SHIFT] = LBR_NOT_SUPP; arch_lbr_ctl_map[PERF_SAMPLE_BRANCH_CALL_SHIFT] = LBR_NOT_SUPP; } x86_pmu.lbr_ctl_mask = ARCH_LBR_CTL_MASK; x86_pmu.lbr_ctl_map = arch_lbr_ctl_map; if (!x86_pmu.lbr_cpl && !x86_pmu.lbr_filter) x86_pmu.lbr_ctl_map = NULL; x86_pmu.lbr_reset = intel_pmu_arch_lbr_reset; if (arch_lbr_xsave) { x86_pmu.lbr_save = intel_pmu_arch_lbr_xsaves; x86_pmu.lbr_restore = intel_pmu_arch_lbr_xrstors; x86_pmu.lbr_read = intel_pmu_arch_lbr_read_xsave; pr_cont("XSAVE "); } else { x86_pmu.lbr_save = intel_pmu_arch_lbr_save; x86_pmu.lbr_restore = intel_pmu_arch_lbr_restore; x86_pmu.lbr_read = intel_pmu_arch_lbr_read; } pr_cont("Architectural LBR, "); return; clear_arch_lbr: clear_cpu_cap(&boot_cpu_data, X86_FEATURE_ARCH_LBR); } /** * x86_perf_get_lbr - get the LBR records information * * @lbr: the caller's memory to store the LBR records information * * Returns: 0 indicates the LBR info has been successfully obtained */ int x86_perf_get_lbr(struct x86_pmu_lbr *lbr) { int lbr_fmt = x86_pmu.intel_cap.lbr_format; lbr->nr = x86_pmu.lbr_nr; lbr->from = x86_pmu.lbr_from; lbr->to = x86_pmu.lbr_to; lbr->info = (lbr_fmt == LBR_FORMAT_INFO) ? x86_pmu.lbr_info : 0; return 0; } EXPORT_SYMBOL_GPL(x86_perf_get_lbr); struct event_constraint vlbr_constraint = __EVENT_CONSTRAINT(INTEL_FIXED_VLBR_EVENT, (1ULL << INTEL_PMC_IDX_FIXED_VLBR), FIXED_EVENT_FLAGS, 1, 0, PERF_X86_EVENT_LBR_SELECT);
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