diff options
Diffstat (limited to 'arch/x86/events/intel/lbr.c')
-rw-r--r-- | arch/x86/events/intel/lbr.c | 502 |
1 files changed, 135 insertions, 367 deletions
diff --git a/arch/x86/events/intel/lbr.c b/arch/x86/events/intel/lbr.c index 8043213b75a5..8259d725054d 100644 --- a/arch/x86/events/intel/lbr.c +++ b/arch/x86/events/intel/lbr.c @@ -4,18 +4,9 @@ #include <asm/perf_event.h> #include <asm/msr.h> -#include <asm/insn.h> #include "../perf_event.h" -static const enum { - LBR_EIP_FLAGS = 1, - LBR_TSX = 2, -} lbr_desc[LBR_FORMAT_MAX_KNOWN + 1] = { - [LBR_FORMAT_EIP_FLAGS] = LBR_EIP_FLAGS, - [LBR_FORMAT_EIP_FLAGS2] = LBR_EIP_FLAGS | LBR_TSX, -}; - /* * Intel LBR_SELECT bits * Intel Vol3a, April 2011, Section 16.7 Table 16-10 @@ -74,65 +65,6 @@ static const enum { #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 @@ -243,7 +175,7 @@ void intel_pmu_lbr_reset_64(void) 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.intel_cap.lbr_format == LBR_FORMAT_INFO) + if (x86_pmu.lbr_has_info) wrmsrl(x86_pmu.lbr_info + i, 0); } } @@ -286,9 +218,9 @@ enum { }; /* - * For formats with LBR_TSX flags (e.g. 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 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 @@ -296,7 +228,7 @@ enum { * * Therefore, if: * - * 1) LBR has TSX format + * 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 @@ -305,11 +237,10 @@ enum { */ static inline bool lbr_from_signext_quirk_needed(void) { - int lbr_format = x86_pmu.intel_cap.lbr_format; bool tsx_support = boot_cpu_has(X86_FEATURE_HLE) || boot_cpu_has(X86_FEATURE_RTM); - return !tsx_support && (lbr_desc[lbr_format] & LBR_TSX); + return !tsx_support; } static DEFINE_STATIC_KEY_FALSE(lbr_from_quirk_key); @@ -427,12 +358,12 @@ rdlbr_all(struct lbr_entry *lbr, unsigned int idx, bool need_info) void intel_pmu_lbr_restore(void *ctx) { - bool need_info = x86_pmu.intel_cap.lbr_format == LBR_FORMAT_INFO; struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); struct x86_perf_task_context *task_ctx = ctx; - int i; - unsigned lbr_idx, mask; + 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++) { @@ -444,7 +375,7 @@ void intel_pmu_lbr_restore(void *ctx) lbr_idx = (tos - i) & mask; wrlbr_from(lbr_idx, 0); wrlbr_to(lbr_idx, 0); - if (x86_pmu.intel_cap.lbr_format == LBR_FORMAT_INFO) + if (need_info) wrlbr_info(lbr_idx, 0); } @@ -519,9 +450,9 @@ static void __intel_pmu_lbr_restore(void *ctx) void intel_pmu_lbr_save(void *ctx) { - bool need_info = x86_pmu.intel_cap.lbr_format == LBR_FORMAT_INFO; 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; @@ -778,6 +709,7 @@ void intel_pmu_lbr_disable_all(void) 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; @@ -793,15 +725,11 @@ void intel_pmu_lbr_read_32(struct cpu_hw_events *cpuc) rdmsrl(x86_pmu.lbr_from + lbr_idx, msr_lastbranch.lbr); - cpuc->lbr_entries[i].from = msr_lastbranch.from; - cpuc->lbr_entries[i].to = msr_lastbranch.to; - cpuc->lbr_entries[i].mispred = 0; - cpuc->lbr_entries[i].predicted = 0; - cpuc->lbr_entries[i].in_tx = 0; - cpuc->lbr_entries[i].abort = 0; - cpuc->lbr_entries[i].cycles = 0; - cpuc->lbr_entries[i].type = 0; - cpuc->lbr_entries[i].reserved = 0; + 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; @@ -816,7 +744,7 @@ 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; - int lbr_format = x86_pmu.intel_cap.lbr_format; + struct perf_branch_entry *br = cpuc->lbr_entries; u64 tos = intel_pmu_lbr_tos(); int i; int out = 0; @@ -831,9 +759,7 @@ void intel_pmu_lbr_read_64(struct cpu_hw_events *cpuc) 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; - int skip = 0; u16 cycles = 0; - int lbr_flags = lbr_desc[lbr_format]; from = rdlbr_from(lbr_idx, NULL); to = rdlbr_to(lbr_idx, NULL); @@ -845,37 +771,39 @@ void intel_pmu_lbr_read_64(struct cpu_hw_events *cpuc) if (call_stack && !from) break; - if (lbr_format == LBR_FORMAT_INFO && need_info) { - u64 info; - - info = rdlbr_info(lbr_idx, NULL); - mis = !!(info & LBR_INFO_MISPRED); - pred = !mis; - in_tx = !!(info & LBR_INFO_IN_TX); - abort = !!(info & LBR_INFO_ABORT); - cycles = (info & LBR_INFO_CYCLES); - } - - if (lbr_format == LBR_FORMAT_TIME) { - mis = !!(from & LBR_FROM_FLAG_MISPRED); - pred = !mis; - skip = 1; - cycles = ((to >> 48) & LBR_INFO_CYCLES); - - to = (u64)((((s64)to) << 16) >> 16); - } - - if (lbr_flags & LBR_EIP_FLAGS) { - mis = !!(from & LBR_FROM_FLAG_MISPRED); - pred = !mis; - skip = 1; - } - if (lbr_flags & LBR_TSX) { - in_tx = !!(from & LBR_FROM_FLAG_IN_TX); - abort = !!(from & LBR_FROM_FLAG_ABORT); - skip = 3; + 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); + } } - from = (u64)((((s64)from) << skip) >> skip); /* * Some CPUs report duplicated abort records, @@ -888,52 +816,54 @@ void intel_pmu_lbr_read_64(struct cpu_hw_events *cpuc) if (abort && x86_pmu.lbr_double_abort && out > 0) out--; - cpuc->lbr_entries[out].from = from; - cpuc->lbr_entries[out].to = to; - cpuc->lbr_entries[out].mispred = mis; - cpuc->lbr_entries[out].predicted = pred; - cpuc->lbr_entries[out].in_tx = in_tx; - cpuc->lbr_entries[out].abort = abort; - cpuc->lbr_entries[out].cycles = cycles; - cpuc->lbr_entries[out].type = 0; - cpuc->lbr_entries[out].reserved = 0; + 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) { - if (!static_cpu_has(X86_FEATURE_ARCH_LBR) || !x86_pmu.lbr_br_type) - return 0; + int type = 0; + + if (static_branch_likely(&x86_lbr_type)) + type = (info & LBR_INFO_BR_TYPE) >> LBR_INFO_BR_TYPE_OFFSET; - return (info & LBR_INFO_BR_TYPE) >> LBR_INFO_BR_TYPE_OFFSET; + return type; } static __always_inline bool get_lbr_mispred(u64 info) { - if (static_cpu_has(X86_FEATURE_ARCH_LBR) && !x86_pmu.lbr_mispred) - return 0; + bool mispred = 0; - return !!(info & LBR_INFO_MISPRED); -} - -static __always_inline bool get_lbr_predicted(u64 info) -{ - if (static_cpu_has(X86_FEATURE_ARCH_LBR) && !x86_pmu.lbr_mispred) - return 0; + if (static_branch_likely(&x86_lbr_mispred)) + mispred = !!(info & LBR_INFO_MISPRED); - return !(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) && - !(x86_pmu.lbr_timed_lbr && info & LBR_INFO_CYC_CNT_VALID)) - return 0; + (!static_branch_likely(&x86_lbr_cycles) || + !(info & LBR_INFO_CYC_CNT_VALID))) + cycles = 0; - return info & LBR_INFO_CYCLES; + return cycles; } static void intel_pmu_store_lbr(struct cpu_hw_events *cpuc, @@ -958,15 +888,16 @@ static void intel_pmu_store_lbr(struct cpu_hw_events *cpuc, 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 = get_lbr_predicted(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); - e->reserved = 0; } cpuc->lbr_stack.nr = i; @@ -1106,6 +1037,14 @@ static int intel_pmu_setup_hw_lbr_filter(struct perf_event *event) 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; } @@ -1120,7 +1059,7 @@ static int intel_pmu_setup_hw_lbr_filter(struct perf_event *event) if ((br_type & PERF_SAMPLE_BRANCH_NO_CYCLES) && (br_type & PERF_SAMPLE_BRANCH_NO_FLAGS) && - (x86_pmu.intel_cap.lbr_format == LBR_FORMAT_INFO)) + x86_pmu.lbr_has_info) reg->config |= LBR_NO_INFO; return 0; @@ -1152,219 +1091,6 @@ int intel_pmu_setup_lbr_filter(struct perf_event *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_UNKNOWN, /* X86_BR_IRET */ - PERF_BR_COND, /* X86_BR_JCC */ - PERF_BR_UNCOND, /* X86_BR_JMP */ - PERF_BR_UNKNOWN, /* 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, @@ -1618,9 +1344,6 @@ void intel_pmu_lbr_init_hsw(void) x86_pmu.lbr_sel_map = hsw_lbr_sel_map; x86_get_pmu(smp_processor_id())->task_ctx_cache = create_lbr_kmem_cache(size, 0); - - if (lbr_from_signext_quirk_needed()) - static_branch_enable(&lbr_from_quirk_key); } /* skylake */ @@ -1706,6 +1429,42 @@ void intel_pmu_lbr_init_knl(void) 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 @@ -1726,6 +1485,9 @@ static bool is_arch_lbr_xsave_available(void) * 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; @@ -1765,6 +1527,12 @@ void __init intel_pmu_arch_lbr_init(void) 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) { @@ -1828,7 +1596,7 @@ void __init intel_pmu_arch_lbr_init(void) return; clear_arch_lbr: - clear_cpu_cap(&boot_cpu_data, X86_FEATURE_ARCH_LBR); + setup_clear_cpu_cap(X86_FEATURE_ARCH_LBR); } /** |