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1//===-- xray_records.h ------------------------------------------*- C++ -*-===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//9// This file is a part of XRay, a dynamic runtime instrumentation system.10//11// This header exposes some record types useful for the XRay in-memory logging12// implementation.13//14//===----------------------------------------------------------------------===//15 16#ifndef XRAY_XRAY_RECORDS_H17#define XRAY_XRAY_RECORDS_H18 19#include <cstdint>20 21namespace __xray {22 23enum FileTypes {24 NAIVE_LOG = 0,25 FDR_LOG = 1,26};27 28// FDR mode use of the union field in the XRayFileHeader.29struct alignas(16) FdrAdditionalHeaderData {30 uint64_t ThreadBufferSize;31};32 33static_assert(sizeof(FdrAdditionalHeaderData) == 16,34 "FdrAdditionalHeaderData != 16 bytes");35 36// This data structure is used to describe the contents of the file. We use this37// for versioning the supported XRay file formats.38struct alignas(32) XRayFileHeader {39 uint16_t Version = 0;40 41 // The type of file we're writing out. See the FileTypes enum for more42 // information. This allows different implementations of the XRay logging to43 // have different files for different information being stored.44 uint16_t Type = 0;45 46 // What follows are a set of flags that indicate useful things for when47 // reading the data in the file.48 bool ConstantTSC : 1;49 bool NonstopTSC : 1;50 51 // The frequency by which TSC increases per-second.52 alignas(8) uint64_t CycleFrequency = 0;53 54 union {55 char FreeForm[16];56 // The current civiltime timestamp, as retrieved from 'clock_gettime'. This57 // allows readers of the file to determine when the file was created or58 // written down.59 struct timespec TS;60 61 struct FdrAdditionalHeaderData FdrData;62 };63} __attribute__((packed));64 65static_assert(sizeof(XRayFileHeader) == 32, "XRayFileHeader != 32 bytes");66 67enum RecordTypes {68 NORMAL = 0,69 ARG_PAYLOAD = 1,70};71 72struct alignas(32) XRayRecord {73 // This is the type of the record being written. We use 16 bits to allow us to74 // treat this as a discriminant, and so that the first 4 bytes get packed75 // properly. See RecordTypes for more supported types.76 uint16_t RecordType = RecordTypes::NORMAL;77 78 // The CPU where the thread is running. We assume number of CPUs <= 256.79 uint8_t CPU = 0;80 81 // The type of the event. One of the following:82 // ENTER = 083 // EXIT = 184 // TAIL_EXIT = 285 // ENTER_ARG = 386 uint8_t Type = 0;87 88 // The function ID for the record.89 int32_t FuncId = 0;90 91 // Get the full 8 bytes of the TSC when we get the log record.92 uint64_t TSC = 0;93 94 // The thread ID for the currently running thread.95 uint32_t TId = 0;96 97 // The ID of process that is currently running98 uint32_t PId = 0;99 100 // Use some bytes in the end of the record for buffers.101 char Buffer[8] = {};102} __attribute__((packed));103 104static_assert(sizeof(XRayRecord) == 32, "XRayRecord != 32 bytes");105 106struct alignas(32) XRayArgPayload {107 // We use the same 16 bits as a discriminant for the records in the log here108 // too, and so that the first 4 bytes are packed properly.109 uint16_t RecordType = RecordTypes::ARG_PAYLOAD;110 111 // Add a few bytes to pad.112 uint8_t Padding[2] = {};113 114 // The function ID for the record.115 int32_t FuncId = 0;116 117 // The thread ID for the currently running thread.118 uint32_t TId = 0;119 120 // The ID of process that is currently running121 uint32_t PId = 0;122 123 // The argument payload.124 uint64_t Arg = 0;125 126 // The rest of this record ought to be left as padding.127 uint8_t TailPadding[8] = {};128} __attribute__((packed));129 130static_assert(sizeof(XRayArgPayload) == 32, "XRayArgPayload != 32 bytes");131 132} // namespace __xray133 134#endif // XRAY_XRAY_RECORDS_H135