llvm-project/compiler-rt/lib/xray/xray_fdr_logging.h

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[XRay][compiler-rt] XRay Flight Data Recorder Mode Summary: In this change we introduce the notion of a "flight data recorder" mode for XRay logging, where XRay logs in-memory first, and write out data on-demand as required (as opposed to the naive implementation that keeps logging while tracing is "on"). This depends on D26232 where we implement the core data structure for holding the buffers that threads will be using to write out records of operation. This implementation only currently works on x86_64 and depends heavily on the TSC math to write out smaller records to the inmemory buffers. Also, this implementation defines two different kinds of records with different sizes (compared to the current naive implementation): a MetadataRecord (16 bytes) and a FunctionRecord (8 bytes). MetadataRecord entries are meant to write out information like the thread ID for which the metadata record is defined for, whether the execution of a thread moved to a different CPU, etc. while a FunctionRecord represents the different kinds of function call entry/exit records we might encounter in the course of a thread's execution along with a delta from the last time the logging handler was called. While this implementation is not exactly what is described in the original XRay whitepaper, this one gives us an initial implementation that we can iterate and build upon. Reviewers: echristo, rSerge, majnemer Subscribers: mehdi_amini, llvm-commits, mgorny Differential Revision: https://reviews.llvm.org/D27038 llvm-svn: 293015
2017-01-25 11:50:46 +08:00
//===-- xray_fdr_logging.h ------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file is a part of XRay, a function call tracing system.
//
//===----------------------------------------------------------------------===//
#ifndef XRAY_XRAY_FDR_LOGGING_H
#define XRAY_XRAY_FDR_LOGGING_H
#include "xray/xray_log_interface.h"
[XRay] [compiler-rt] Refactor logic for xray fdr logging. NFC. Summary: Separated the IO and the thread local storage state machine of logging from the writing of log records once the contents are deterministic. Finer granularity functions are provided as inline functions in the same header such that stack does not grow due to the functions being separated. An executable utility xray_fdr_log_printer is also implemented to use the finest granularity functions to produce binary test data in the FDR format with a relatively convenient text input. For example, one can take a file with textual contents layed out in rows and feed it to the binary to generate data that llvm-xray convert can then read. This is a convenient way to build a test suite for llvm-xray convert to ensure it's robust to the fdr format. Example: $cat myFile.txt NewBuffer : { time = 2 , Tid=5} NewCPU : { CPU =1 , TSC = 123} Function : { FuncId = 5, TSCDelta = 3, EntryType = Entry } Function : { FuncId = 5, TSCDelta = 5, EntryType = Exit} TSCWrap : { TSC = 678 } Function : { FuncId = 6, TSCDelta = 0, EntryType = Entry } Function : { FuncId = 6, TSCDelta = 50, EntryType = Exit } EOB : { } $cat myFile.txt | ./bin/xray_fdr_log_printer > /tmp/binarydata.bin $./bin/llvm-xray convert -output-format=yaml -output=- /tmp/binarydata.bin yaml format comes out as expected. Reviewers: dberris, pelikan Reviewed By: dberris Subscribers: llvm-commits, mgorny Differential Revision: https://reviews.llvm.org/D30850 llvm-svn: 297801
2017-03-15 11:12:01 +08:00
#include "xray_fdr_log_records.h"
[XRay][compiler-rt] XRay Flight Data Recorder Mode Summary: In this change we introduce the notion of a "flight data recorder" mode for XRay logging, where XRay logs in-memory first, and write out data on-demand as required (as opposed to the naive implementation that keeps logging while tracing is "on"). This depends on D26232 where we implement the core data structure for holding the buffers that threads will be using to write out records of operation. This implementation only currently works on x86_64 and depends heavily on the TSC math to write out smaller records to the inmemory buffers. Also, this implementation defines two different kinds of records with different sizes (compared to the current naive implementation): a MetadataRecord (16 bytes) and a FunctionRecord (8 bytes). MetadataRecord entries are meant to write out information like the thread ID for which the metadata record is defined for, whether the execution of a thread moved to a different CPU, etc. while a FunctionRecord represents the different kinds of function call entry/exit records we might encounter in the course of a thread's execution along with a delta from the last time the logging handler was called. While this implementation is not exactly what is described in the original XRay whitepaper, this one gives us an initial implementation that we can iterate and build upon. Reviewers: echristo, rSerge, majnemer Subscribers: mehdi_amini, llvm-commits, mgorny Differential Revision: https://reviews.llvm.org/D27038 llvm-svn: 293015
2017-01-25 11:50:46 +08:00
// FDR (Flight Data Recorder) Mode
// ===============================
//
// The XRay whitepaper describes a mode of operation for function call trace
// logging that involves writing small records into an in-memory circular
// buffer, that then gets logged to disk on demand. To do this efficiently and
// capture as much data as we can, we use smaller records compared to the
// default mode of always writing fixed-size records.
namespace __xray {
XRayLogInitStatus fdrLoggingInit(size_t BufferSize, size_t BufferMax,
[XRay] [compiler-rt] Refactor logic for xray fdr logging. NFC. Summary: Separated the IO and the thread local storage state machine of logging from the writing of log records once the contents are deterministic. Finer granularity functions are provided as inline functions in the same header such that stack does not grow due to the functions being separated. An executable utility xray_fdr_log_printer is also implemented to use the finest granularity functions to produce binary test data in the FDR format with a relatively convenient text input. For example, one can take a file with textual contents layed out in rows and feed it to the binary to generate data that llvm-xray convert can then read. This is a convenient way to build a test suite for llvm-xray convert to ensure it's robust to the fdr format. Example: $cat myFile.txt NewBuffer : { time = 2 , Tid=5} NewCPU : { CPU =1 , TSC = 123} Function : { FuncId = 5, TSCDelta = 3, EntryType = Entry } Function : { FuncId = 5, TSCDelta = 5, EntryType = Exit} TSCWrap : { TSC = 678 } Function : { FuncId = 6, TSCDelta = 0, EntryType = Entry } Function : { FuncId = 6, TSCDelta = 50, EntryType = Exit } EOB : { } $cat myFile.txt | ./bin/xray_fdr_log_printer > /tmp/binarydata.bin $./bin/llvm-xray convert -output-format=yaml -output=- /tmp/binarydata.bin yaml format comes out as expected. Reviewers: dberris, pelikan Reviewed By: dberris Subscribers: llvm-commits, mgorny Differential Revision: https://reviews.llvm.org/D30850 llvm-svn: 297801
2017-03-15 11:12:01 +08:00
void *Options, size_t OptionsSize);
XRayLogInitStatus fdrLoggingFinalize();
void fdrLoggingHandleArg0(int32_t FuncId, XRayEntryType Entry);
XRayLogFlushStatus fdrLoggingFlush();
XRayLogInitStatus fdrLoggingReset();
[XRay][compiler-rt] XRay Flight Data Recorder Mode Summary: In this change we introduce the notion of a "flight data recorder" mode for XRay logging, where XRay logs in-memory first, and write out data on-demand as required (as opposed to the naive implementation that keeps logging while tracing is "on"). This depends on D26232 where we implement the core data structure for holding the buffers that threads will be using to write out records of operation. This implementation only currently works on x86_64 and depends heavily on the TSC math to write out smaller records to the inmemory buffers. Also, this implementation defines two different kinds of records with different sizes (compared to the current naive implementation): a MetadataRecord (16 bytes) and a FunctionRecord (8 bytes). MetadataRecord entries are meant to write out information like the thread ID for which the metadata record is defined for, whether the execution of a thread moved to a different CPU, etc. while a FunctionRecord represents the different kinds of function call entry/exit records we might encounter in the course of a thread's execution along with a delta from the last time the logging handler was called. While this implementation is not exactly what is described in the original XRay whitepaper, this one gives us an initial implementation that we can iterate and build upon. Reviewers: echristo, rSerge, majnemer Subscribers: mehdi_amini, llvm-commits, mgorny Differential Revision: https://reviews.llvm.org/D27038 llvm-svn: 293015
2017-01-25 11:50:46 +08:00
} // namespace __xray
#endif // XRAY_XRAY_FDR_LOGGING_H