//===-- xray_fdr_logging.cpp -----------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file is a part of XRay, a dynamic runtime instrumentation system.
//
// Here we implement the Flight Data Recorder mode for XRay, where we use
// compact structures to store records in memory as well as when writing out the
// data to files.
//
//===----------------------------------------------------------------------===//
#include "xray_fdr_logging.h"
#include <cassert>
#include <errno.h>
#include <limits>
#include <memory>
#include <pthread.h>
#include <sys/time.h>
#include <time.h>
#include <unistd.h>
#include "sanitizer_common/sanitizer_allocator_internal.h"
#include "sanitizer_common/sanitizer_atomic.h"
#include "sanitizer_common/sanitizer_common.h"
#include "xray/xray_interface.h"
#include "xray/xray_records.h"
#include "xray_allocator.h"
#include "xray_buffer_queue.h"
#include "xray_defs.h"
#include "xray_fdr_controller.h"
#include "xray_fdr_flags.h"
#include "xray_fdr_log_writer.h"
#include "xray_flags.h"
#include "xray_recursion_guard.h"
#include "xray_tsc.h"
#include "xray_utils.h"
namespace __xray {
static atomic_sint32_t LoggingStatus = {
XRayLogInitStatus::XRAY_LOG_UNINITIALIZED};
namespace {
// Group together thread-local-data in a struct, then hide it behind a function
// call so that it can be initialized on first use instead of as a global. We
// force the alignment to 64-bytes for x86 cache line alignment, as this
// structure is used in the hot path of implementation.
struct XRAY_TLS_ALIGNAS(64) ThreadLocalData {
BufferQueue::Buffer Buffer{};
BufferQueue *BQ = nullptr;
using LogWriterStorage =
typename std::aligned_storage<sizeof(FDRLogWriter),
alignof(FDRLogWriter)>::type;
LogWriterStorage LWStorage;
FDRLogWriter *Writer = nullptr;
using ControllerStorage =
typename std::aligned_storage<sizeof(FDRController<>),
alignof(FDRController<>)>::type;
ControllerStorage CStorage;
FDRController<> *Controller = nullptr;
};
} // namespace
static_assert(std::is_trivially_destructible<ThreadLocalData>::value,
"ThreadLocalData must be trivially destructible");
// Use a global pthread key to identify thread-local data for logging.
static pthread_key_t Key;
// Global BufferQueue.
static std::aligned_storage<sizeof(BufferQueue)>::type BufferQueueStorage;
static BufferQueue *BQ = nullptr;
// Global thresholds for function durations.
static atomic_uint64_t ThresholdTicks{0};
// Global for ticks per second.
static atomic_uint64_t TicksPerSec{0};
static atomic_sint32_t LogFlushStatus = {
XRayLogFlushStatus::XRAY_LOG_NOT_FLUSHING};
// This function will initialize the thread-local data structure used by the FDR
// logging implementation and return a reference to it. The implementation
// details require a bit of care to maintain.
//
// First, some requirements on the implementation in general:
//
// - XRay handlers should not call any memory allocation routines that may
// delegate to an instrumented implementation. This means functions like
// malloc() and free() should not be called while instrumenting.
//
// - We would like to use some thread-local data initialized on first-use of
// the XRay instrumentation. These allow us to implement unsynchronized
// routines that access resources associated with the thread.
//
// The implementation here uses a few mechanisms that allow us to provide both
// the requirements listed above. We do this by:
//
// 1. Using a thread-local aligned storage buffer for representing the
// ThreadLocalData struct. This data will be uninitialized memory by
// design.
//
// 2. Not requiring a thread exit handler/implementation, keeping the
// thread-local as purely a collection of references/data that do not
// require cleanup.
//
// We're doing this to avoid using a `thread_local` object that has a
// non-trivial destructor, because the C++ runtime might call std::malloc(...)
// to register calls to destructors. Deadlocks may arise when, for example, an
// externally provided malloc implementation is XRay instrumented, and
// initializing the thread-locals involves calling into malloc. A malloc
// implementation that does global synchronization might be holding a lock for a
// critical section, calling a function that might be XRay instrumented (and
// thus in turn calling into malloc by virtue of registration of the
// thread_local's destructor).
#if XRAY_HAS_TLS_ALIGNAS
static_assert(alignof(ThreadLocalData) >= 64,
"ThreadLocalData must be cache line aligned.");
#endif
static ThreadLocalData &getThreadLocalData() {
thread_local typename std::aligned_storage<
sizeof(ThreadLocalData), alignof(ThreadLocalData)>::type TLDStorage{};
if (pthread_getspecific(Key) == NULL) {
new (reinterpret_cast<ThreadLocalData *>(&TLDStorage)) ThreadLocalData{};
pthread_setspecific(Key, &TLDStorage);
}
return *reinterpret_cast<ThreadLocalData *>(&TLDStorage);
}
static XRayFileHeader &fdrCommonHeaderInfo() {
static std::aligned_storage<sizeof(XRayFileHeader)>::type HStorage;
static pthread_once_t OnceInit = PTHREAD_ONCE_INIT;
static bool TSCSupported = true;
static uint64_t CycleFrequency = NanosecondsPerSecond;
pthread_once(
&OnceInit, +[] {
XRayFileHeader &H = reinterpret_cast<XRayFileHeader &>(HStorage);
// Version 2 of the log writes the extents of the buffer, instead of
// relying on an end-of-buffer record.
// Version 3 includes PID metadata record.
// Version 4 includes CPU data in the custom event records.
// Version 5 uses relative deltas for custom and typed event records,
// and removes the CPU data in custom event records (similar to how
// function records use deltas instead of full TSCs and rely on other
// metadata records for TSC wraparound and CPU migration).
H.Version = 5;
H.Type = FileTypes::FDR_LOG;
// Test for required CPU features and cache the cycle frequency
TSCSupported = probeRequiredCPUFeatures();
if (TSCSupported)
CycleFrequency = getTSCFrequency();
H.CycleFrequency = CycleFrequency;
// FIXME: Actually check whether we have 'constant_tsc' and
// 'nonstop_tsc' before setting the values in the header.
H.ConstantTSC = 1;
H.NonstopTSC = 1;
});
return reinterpret_cast<XRayFileHeader &>(HStorage);
}
// This is the iterator implementation, which knows how to handle FDR-mode
// specific buffers. This is used as an implementation of the iterator function
// needed by __xray_set_buffer_iterator(...). It maintains a global state of the
// buffer iteration for the currently installed FDR mode buffers. In particular:
//
// - If the argument represents the initial state of XRayBuffer ({nullptr, 0})
// then the iterator returns the header information.
// - If the argument represents the header information ({address of header
// info, size of the header info}) then it returns the first FDR buffer's
// address and extents.
// - It will keep returning the next buffer and extents as there are more
// buffers to process. When the input represents the last buffer, it will
// return the initial state to signal completion ({nullptr, 0}).
//
// See xray/xray_log_interface.h for more details on the requirements for the
// implementations of __xray_set_buffer_iterator(...) and
// __xray_log_process_buffers(...).
XRayBuffer fdrIterator(const XRayBuffer B) {
DCHECK(internal_strcmp(__xray_log_get_current_mode(), "xray-fdr") == 0);
DCHECK(BQ->finalizing());
if (BQ == nullptr || !BQ->finalizing()) {
if (Verbosity())
Report(
"XRay FDR: Failed global buffer queue is null or not finalizing!\n");
return {nullptr, 0};
}
// We use a global scratch-pad for the header information, which only gets
// initialized the first time this function is called. We'll update one part
// of this information with some relevant data (in particular the number of
// buffers to expect).
static std::aligned_storage<sizeof(XRayFileHeader)>::type HeaderStorage;
static pthread_once_t HeaderOnce = PTHREAD_ONCE_INIT;
pthread_once(
&HeaderOnce, +[] {
reinterpret_cast<XRayFileHeader &>(HeaderStorage) =
fdrCommonHeaderInfo();
});
// We use a convenience alias for code referring to Header from here on out.
auto &Header = reinterpret_cast<XRayFileHeader &>(HeaderStorage);
if (B.Data == nullptr && B.Size == 0) {
Header.FdrData = FdrAdditionalHeaderData{BQ->ConfiguredBufferSize()};
return XRayBuffer{static_cast<void *>(&Header), sizeof(Header)};
}
static BufferQueue::const_iterator It{};
static BufferQueue::const_iterator End{};
static uint8_t *CurrentBuffer{nullptr};
static size_t SerializedBufferSize = 0;
if (B.Data == static_cast<void *>(&Header) && B.Size == sizeof(Header)) {
// From this point on, we provide raw access to the raw buffer we're getting
// from the BufferQueue. We're relying on the iterators from the current
// Buffer queue.
It = BQ->cbegin();
End = BQ->cend();
}
if (CurrentBuffer != nullptr) {
deallocateBuffer(CurrentBuffer, SerializedBufferSize);
CurrentBuffer = nullptr;
}
if (It == End)
return {nullptr, 0};
// Set up the current buffer to contain the extents like we would when writing
// out to disk. The difference here would be that we still write "empty"
// buffers, or at least go through the iterators faithfully to let the
// handlers see the empty buffers in the queue.
//
// We need this atomic fence here to ensure that writes happening to the
// buffer have been committed before we load the extents atomically. Because
// the buffer is not explicitly synchronised across threads, we rely on the
// fence ordering to ensure that writes we expect to have been completed
// before the fence are fully committed before we read the extents.
atomic_thread_fence(memory_order_acquire);
auto BufferSize = atomic_load(It->Extents, memory_order_acquire);
SerializedBufferSize = BufferSize + sizeof(MetadataRecord);
CurrentBuffer = allocateBuffer(SerializedBufferSize);
if (CurrentBuffer == nullptr)
return {nullptr, 0};
// Write out the extents as a Metadata Record into the CurrentBuffer.
MetadataRecord ExtentsRecord;
ExtentsRecord.Type = uint8_t(RecordType::Metadata);
ExtentsRecord.RecordKind =
uint8_t(MetadataRecord::RecordKinds::BufferExtents);
internal_memcpy(ExtentsRecord.Data, &BufferSize, sizeof(BufferSize));
auto AfterExtents =
static_cast<char *>(internal_memcpy(CurrentBuffer, &ExtentsRecord,
sizeof(MetadataRecord))) +
sizeof(MetadataRecord);
internal_memcpy(AfterExtents, It->Data, BufferSize);
XRayBuffer Result;
Result.Data = CurrentBuffer;
Result.Size = SerializedBufferSize;
++It;
return Result;
}
// Must finalize before flushing.
XRayLogFlushStatus fdrLoggingFlush() XRAY_NEVER_INSTRUMENT {
if (atomic_load(&LoggingStatus, memory_order_acquire) !=
XRayLogInitStatus::XRAY_LOG_FINALIZED) {
if (Verbosity())
Report("Not flushing log, implementation is not finalized.\n");
return XRayLogFlushStatus::XRAY_LOG_NOT_FLUSHING;
}
s32 Result = XRayLogFlushStatus::XRAY_LOG_NOT_FLUSHING;
if (!atomic_compare_exchange_strong(&LogFlushStatus, &Result,
XRayLogFlushStatus::XRAY_LOG_FLUSHING,
memory_order_release)) {
if (Verbosity())
Report("Not flushing log, implementation is still finalizing.\n");
return static_cast<XRayLogFlushStatus>(Result);
}
if (BQ == nullptr) {
if (Verbosity())
Report("Cannot flush when global buffer queue is null.\n");
return XRayLogFlushStatus::XRAY_LOG_NOT_FLUSHING;
}
// We wait a number of milliseconds to allow threads to see that we've
// finalised before attempting to flush the log.
SleepForMillis(fdrFlags()->grace_period_ms);
// At this point, we're going to uninstall the iterator implementation, before
// we decide to do anything further with the global buffer queue.
__xray_log_remove_buffer_iterator();
// Once flushed, we should set the global status of the logging implementation
// to "uninitialized" to allow for FDR-logging multiple runs.
auto ResetToUnitialized = at_scope_exit([] {
atomic_store(&LoggingStatus, XRayLogInitStatus::XRAY_LOG_UNINITIALIZED,
memory_order_release);
});
auto CleanupBuffers = at_scope_exit([] {
auto &TLD = getThreadLocalData();
if (TLD.Controller != nullptr)
TLD.Controller->flush();
});
if (fdrFlags()->no_file_flush) {
if (Verbosity())
Report("XRay FDR: Not flushing to file, 'no_file_flush=true'.\n");
atomic_store(&LogFlushStatus, XRayLogFlushStatus::XRAY_LOG_FLUSHED,
memory_order_release);
return XRayLogFlushStatus::XRAY_LOG_FLUSHED;
}
// We write out the file in the following format:
//
// 1) We write down the XRay file header with version 1, type FDR_LOG.
// 2) Then we use the 'apply' member of the BufferQueue that's live, to
// ensure that at this point in time we write down the buffers that have
// been released (and marked "used") -- we dump the full buffer for now
// (fixed-sized) and let the tools reading the buffers deal with the data
// afterwards.
//
LogWriter *LW = LogWriter::Open();
if (LW == nullptr) {
auto Result = XRayLogFlushStatus::XRAY_LOG_NOT_FLUSHING;
atomic_store(&LogFlushStatus, Result, memory_order_release);
return Result;
}
XRayFileHeader Header = fdrCommonHeaderInfo();
Header.FdrData = FdrAdditionalHeaderData{BQ->ConfiguredBufferSize()};
LW->WriteAll(reinterpret_cast<char *>(&Header),
reinterpret_cast<char *>(&Header) + sizeof(Header));
// Release the current thread's buffer before we attempt to write out all the
// buffers. This ensures that in case we had only a single thread going, that
// we are able to capture the data nonetheless.
auto &TLD = getThreadLocalData();
if (TLD.Controller != nullptr)
TLD.Controller->flush();
BQ->apply([&](const BufferQueue::Buffer &B) {
// Starting at version 2 of the FDR logging implementation, we only write
// the records identified by the extents of the buffer. We use the Extents
// from the Buffer and write that out as the first record in the buffer. We
// still use a Metadata record, but fill in the extents instead for the
// data.
MetadataRecord ExtentsRecord;
auto BufferExtents = atomic_load(B.Extents, memory_order_acquire);
DCHECK(BufferExtents <= B.Size);
ExtentsRecord.Type = uint8_t(RecordType::Metadata);
ExtentsRecord.RecordKind =
uint8_t(MetadataRecord::RecordKinds::BufferExtents);
internal_memcpy(ExtentsRecord.Data, &BufferExtents, sizeof(BufferExtents));
if (BufferExtents > 0) {
LW->WriteAll(reinterpret_cast<char *>(&ExtentsRecord),
reinterpret_cast<char *>(&ExtentsRecord) +
sizeof(MetadataRecord));
LW->WriteAll(reinterpret_cast<char *>(B.Data),
reinterpret_cast<char *>(B.Data) + BufferExtents);
}
});
atomic_store(&LogFlushStatus, XRayLogFlushStatus::XRAY_LOG_FLUSHED,
memory_order_release);
return XRayLogFlushStatus::XRAY_LOG_FLUSHED;
}
XRayLogInitStatus fdrLoggingFinalize() XRAY_NEVER_INSTRUMENT {
s32 CurrentStatus = XRayLogInitStatus::XRAY_LOG_INITIALIZED;
if (!atomic_compare_exchange_strong(&LoggingStatus, &CurrentStatus,
XRayLogInitStatus::XRAY_LOG_FINALIZING,
memory_order_release)) {
if (Verbosity())
Report("Cannot finalize log, implementation not initialized.\n");
return static_cast<XRayLogInitStatus>(CurrentStatus);
}
// Do special things to make the log finalize itself, and not allow any more
// operations to be performed until re-initialized.
if (BQ == nullptr) {
if (Verbosity())
Report("Attempting to finalize an uninitialized global buffer!\n");
} else {
BQ->finalize();
}
atomic_store(&LoggingStatus, XRayLogInitStatus::XRAY_LOG_FINALIZED,
memory_order_release);
return XRayLogInitStatus::XRAY_LOG_FINALIZED;
}
struct TSCAndCPU {
uint64_t TSC = 0;
unsigned char CPU = 0;
};
static TSCAndCPU getTimestamp() XRAY_NEVER_INSTRUMENT {
// We want to get the TSC as early as possible, so that we can check whether
// we've seen this CPU before. We also do it before we load anything else,
// to allow for forward progress with the scheduling.
TSCAndCPU Result;
// Test once for required CPU features
static pthread_once_t OnceProbe = PTHREAD_ONCE_INIT;
static bool TSCSupported = true;
pthread_once(
&OnceProbe, +[] { TSCSupported = probeRequiredCPUFeatures(); });
if (TSCSupported) {
Result.TSC = __xray::readTSC(Result.CPU);
} else {
// FIXME: This code needs refactoring as it appears in multiple locations
timespec TS;
int result = clock_gettime(CLOCK_REALTIME, &TS);
if (result != 0) {
Report("clock_gettime(2) return %d, errno=%d", result, int(errno));
TS = {0, 0};
}
Result.CPU = 0;
Result.TSC = TS.tv_sec * __xray::NanosecondsPerSecond + TS.tv_nsec;
}
return Result;
}
thread_local atomic_uint8_t Running{0};
static bool setupTLD(ThreadLocalData &TLD) XRAY_NEVER_INSTRUMENT {
// Check if we're finalizing, before proceeding.
{
auto Status = atomic_load(&LoggingStatus, memory_order_acquire);
if (Status == XRayLogInitStatus::XRAY_LOG_FINALIZING ||
Status == XRayLogInitStatus::XRAY_LOG_FINALIZED) {
if (TLD.Controller != nullptr) {
TLD.Controller->flush();
TLD.Controller = nullptr;
}
return false;
}
}
if (UNLIKELY(TLD.Controller == nullptr)) {
// Set up the TLD buffer queue.
if (UNLIKELY(BQ == nullptr))
return false;
TLD.BQ = BQ;
// Check that we have a valid buffer.
if (TLD.Buffer.Generation != BQ->generation() &&
TLD.BQ->releaseBuffer(TLD.Buffer) != BufferQueue::ErrorCode::Ok)
return false;
// Set up a buffer, before setting up the log writer. Bail out on failure.
if (TLD.BQ->getBuffer(TLD.Buffer) != BufferQueue::ErrorCode::Ok)
return false;
// Set up the Log Writer for this thread.
if (UNLIKELY(TLD.Writer == nullptr)) {
auto *LWStorage = reinterpret_cast<FDRLogWriter *>(&TLD.LWStorage);
new (LWStorage) FDRLogWriter(TLD.Buffer);
TLD.Writer = LWStorage;
} else {
TLD.Writer->resetRecord();
}
auto *CStorage = reinterpret_cast<FDRController<> *>(&TLD.CStorage);
new (CStorage)
FDRController<>(TLD.BQ, TLD.Buffer, *TLD.Writer, clock_gettime,
atomic_load_relaxed(&ThresholdTicks));
TLD.Controller = CStorage;
}
DCHECK_NE(TLD.Controller, nullptr);
return true;
}
void fdrLoggingHandleArg0(int32_t FuncId,
XRayEntryType Entry) XRAY_NEVER_INSTRUMENT {
auto TC = getTimestamp();
auto &TSC = TC.TSC;
auto &CPU = TC.CPU;
RecursionGuard Guard{Running};
if (!Guard)
return;
auto &TLD = getThreadLocalData();
if (!setupTLD(TLD))
return;
switch (Entry) {
case XRayEntryType::ENTRY:
case XRayEntryType::LOG_ARGS_ENTRY:
TLD.Controller->functionEnter(FuncId, TSC, CPU);
return;
case XRayEntryType::EXIT:
TLD.Controller->functionExit(FuncId, TSC, CPU);
return;
case XRayEntryType::TAIL:
TLD.Controller->functionTailExit(FuncId, TSC, CPU);
return;
case XRayEntryType::CUSTOM_EVENT:
case XRayEntryType::TYPED_EVENT:
break;
}
}
void fdrLoggingHandleArg1(int32_t FuncId, XRayEntryType Entry,
uint64_t Arg) XRAY_NEVER_INSTRUMENT {
auto TC = getTimestamp();
auto &TSC = TC.TSC;
auto &CPU = TC.CPU;
RecursionGuard Guard{Running};
if (!Guard)
return;
auto &TLD = getThreadLocalData();
if (!setupTLD(TLD))
return;
switch (Entry) {
case XRayEntryType::ENTRY:
case XRayEntryType::LOG_ARGS_ENTRY:
TLD.Controller->functionEnterArg(FuncId, TSC, CPU, Arg);
return;
case XRayEntryType::EXIT:
TLD.Controller->functionExit(FuncId, TSC, CPU);
return;
case XRayEntryType::TAIL:
TLD.Controller->functionTailExit(FuncId, TSC, CPU);
return;
case XRayEntryType::CUSTOM_EVENT:
case XRayEntryType::TYPED_EVENT:
break;
}
}
void fdrLoggingHandleCustomEvent(void *Event,
std::size_t EventSize) XRAY_NEVER_INSTRUMENT {
auto TC = getTimestamp();
auto &TSC = TC.TSC;
auto &CPU = TC.CPU;
RecursionGuard Guard{Running};
if (!Guard)
return;
// Complain when we ever get at least one custom event that's larger than what
// we can possibly support.
if (EventSize >
static_cast<std::size_t>(std::numeric_limits<int32_t>::max())) {
static pthread_once_t Once = PTHREAD_ONCE_INIT;
pthread_once(
&Once, +[] {
Report("Custom event size too large; truncating to %d.\n",
std::numeric_limits<int32_t>::max());
});
}
auto &TLD = getThreadLocalData();
if (!setupTLD(TLD))
return;
int32_t ReducedEventSize = static_cast<int32_t>(EventSize);
TLD.Controller->customEvent(TSC, CPU, Event, ReducedEventSize);
}
void fdrLoggingHandleTypedEvent(
uint16_t EventType, const void *Event,
std::size_t EventSize) noexcept XRAY_NEVER_INSTRUMENT {
auto TC = getTimestamp();
auto &TSC = TC.TSC;
auto &CPU = TC.CPU;
RecursionGuard Guard{Running};
if (!Guard)
return;
// Complain when we ever get at least one typed event that's larger than what
// we can possibly support.
if (EventSize >
static_cast<std::size_t>(std::numeric_limits<int32_t>::max())) {
static pthread_once_t Once = PTHREAD_ONCE_INIT;
pthread_once(
&Once, +[] {
Report("Typed event size too large; truncating to %d.\n",
std::numeric_limits<int32_t>::max());
});
}
auto &TLD = getThreadLocalData();
if (!setupTLD(TLD))
return;
int32_t ReducedEventSize = static_cast<int32_t>(EventSize);
TLD.Controller->typedEvent(TSC, CPU, EventType, Event, ReducedEventSize);
}
XRayLogInitStatus fdrLoggingInit(size_t, size_t, void *Options,
size_t OptionsSize) XRAY_NEVER_INSTRUMENT {
if (Options == nullptr)
return XRayLogInitStatus::XRAY_LOG_UNINITIALIZED;
s32 CurrentStatus = XRayLogInitStatus::XRAY_LOG_UNINITIALIZED;
if (!atomic_compare_exchange_strong(&LoggingStatus, &CurrentStatus,
XRayLogInitStatus::XRAY_LOG_INITIALIZING,
memory_order_release)) {
if (Verbosity())
Report("Cannot initialize already initialized implementation.\n");
return static_cast<XRayLogInitStatus>(CurrentStatus);
}
if (Verbosity())
Report("Initializing FDR mode with options: %s\n",
static_cast<const char *>(Options));
// TODO: Factor out the flags specific to the FDR mode implementation. For
// now, use the global/single definition of the flags, since the FDR mode
// flags are already defined there.
FlagParser FDRParser;
FDRFlags FDRFlags;
registerXRayFDRFlags(&FDRParser, &FDRFlags);
FDRFlags.setDefaults();
// Override first from the general XRAY_DEFAULT_OPTIONS compiler-provided
// options until we migrate everyone to use the XRAY_FDR_OPTIONS
// compiler-provided options.
FDRParser.ParseString(useCompilerDefinedFlags());
FDRParser.ParseString(useCompilerDefinedFDRFlags());
auto *EnvOpts = GetEnv("XRAY_FDR_OPTIONS");
if (EnvOpts == nullptr)
EnvOpts = "";
FDRParser.ParseString(EnvOpts);
// FIXME: Remove this when we fully remove the deprecated flags.
if (internal_strlen(EnvOpts) == 0) {
FDRFlags.func_duration_threshold_us =
flags()->xray_fdr_log_func_duration_threshold_us;
FDRFlags.grace_period_ms = flags()->xray_fdr_log_grace_period_ms;
}
// The provided options should always override the compiler-provided and
// environment-variable defined options.
FDRParser.ParseString(static_cast<const char *>(Options));
*fdrFlags() = FDRFlags;
auto BufferSize = FDRFlags.buffer_size;
auto BufferMax = FDRFlags.buffer_max;
if (BQ == nullptr) {
bool Success = false;
BQ = reinterpret_cast<BufferQueue *>(&BufferQueueStorage);
new (BQ) BufferQueue(BufferSize, BufferMax, Success);
if (!Success) {
Report("BufferQueue init failed.\n");
return XRayLogInitStatus::XRAY_LOG_UNINITIALIZED;
}
} else {
if (BQ->init(BufferSize, BufferMax) != BufferQueue::ErrorCode::Ok) {
if (Verbosity())
Report("Failed to re-initialize global buffer queue. Init failed.\n");
return XRayLogInitStatus::XRAY_LOG_UNINITIALIZED;
}
}
static pthread_once_t OnceInit = PTHREAD_ONCE_INIT;
pthread_once(
&OnceInit, +[] {
atomic_store(&TicksPerSec,
probeRequiredCPUFeatures() ? getTSCFrequency()
: __xray::NanosecondsPerSecond,
memory_order_release);
pthread_key_create(
&Key, +[](void *TLDPtr) {
if (TLDPtr == nullptr)
return;
auto &TLD = *reinterpret_cast<ThreadLocalData *>(TLDPtr);
if (TLD.BQ == nullptr)
return;
if (TLD.Buffer.Data == nullptr)
return;
auto EC = TLD.BQ->releaseBuffer(TLD.Buffer);
if (EC != BufferQueue::ErrorCode::Ok)
Report("At thread exit, failed to release buffer at %p; "
"error=%s\n",
TLD.Buffer.Data, BufferQueue::getErrorString(EC));
});
});
atomic_store(&ThresholdTicks,
atomic_load_relaxed(&TicksPerSec) *
fdrFlags()->func_duration_threshold_us / 1000000,
memory_order_release);
// Arg1 handler should go in first to avoid concurrent code accidentally
// falling back to arg0 when it should have ran arg1.
__xray_set_handler_arg1(fdrLoggingHandleArg1);
// Install the actual handleArg0 handler after initialising the buffers.
__xray_set_handler(fdrLoggingHandleArg0);
__xray_set_customevent_handler(fdrLoggingHandleCustomEvent);
__xray_set_typedevent_handler(fdrLoggingHandleTypedEvent);
// Install the buffer iterator implementation.
__xray_log_set_buffer_iterator(fdrIterator);
atomic_store(&LoggingStatus, XRayLogInitStatus::XRAY_LOG_INITIALIZED,
memory_order_release);
if (Verbosity())
Report("XRay FDR init successful.\n");
return XRayLogInitStatus::XRAY_LOG_INITIALIZED;
}
bool fdrLogDynamicInitializer() XRAY_NEVER_INSTRUMENT {
XRayLogImpl Impl{
fdrLoggingInit,
fdrLoggingFinalize,
fdrLoggingHandleArg0,
fdrLoggingFlush,
};
auto RegistrationResult = __xray_log_register_mode("xray-fdr", Impl);
if (RegistrationResult != XRayLogRegisterStatus::XRAY_REGISTRATION_OK &&
Verbosity()) {
Report("Cannot register XRay FDR mode to 'xray-fdr'; error = %d\n",
RegistrationResult);
return false;
}
if (flags()->xray_fdr_log ||
!internal_strcmp(flags()->xray_mode, "xray-fdr")) {
auto SelectResult = __xray_log_select_mode("xray-fdr");
if (SelectResult != XRayLogRegisterStatus::XRAY_REGISTRATION_OK &&
Verbosity()) {
Report("Cannot select XRay FDR mode as 'xray-fdr'; error = %d\n",
SelectResult);
return false;
}
}
return true;
}
} // namespace __xray
static auto UNUSED Unused = __xray::fdrLogDynamicInitializer();