Minimal tool to convert xray traces to Chrome's Trace Event Format.
Summary:
Make use of Chrome Trace Event format's Duration events and stack frame dict to
produce Json files that chrome://tracing can visualize from xray function call
traces. Trace Event format is more robust and has several features like
argument logging, function categorization, multi process traces, etc. that we
can add as needed. Duration events cover an important base case.
Part of this change is rearranging the code so that the TrieNode data structure
can be used from multiple tools and can carry parameterized baggage on the
nodes. I put the actual behavior changes in llvm-xray convert exclusively.
Exploring the trace of instrumented llc was pretty nifty if overwhelming.
I can envision this being very useful for analyzing contention scenarios or
tuning parameters like batch sizes in a producer consumer queue. For more
targeted traces likemthis, let's talk about how we want to approach trace
pruning.
Reviewers: dberris, pelikan
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39362
llvm-svn: 317531
Summary:
A new FDR metadata record will support logging a function call argument;
appending multiple metadata records will represent a sequence of arguments
meaning that "holes" are not representable by the buffer format. Each
call argument is currently a 64-bit value (useful for "this" pointers and
synchronization objects).
If present, we put this argument to the function call "entry" record it
belongs to, and alter its type to notify the user of its presence.
Reviewers: dberris
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D32840
llvm-svn: 314269
Summary:
This change adds support for explicit tail-exit records to be written by
the XRay runtime. This lets us differentiate the tail exit
records/events in the log, and allows us to treat those exit events
especially in the future. For now we allow printing those out in YAML
(and reading them in).
Reviewers: kpw, pelikan
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D37964
llvm-svn: 313514
Summary:
The file type packs function trace data onto disk from potentially multiple
threads that are aggregated and flushed during the course of an instrumented
program's runtime.
It is named FDR mode or Flight Data recorder as an analogy to plane
blackboxes, which instrument a running system without access to IO.
The writer code is defined in compiler-rt in xray_fdr_logging.h/cc
Reviewers: rSerge, kcc, dberris
Reviewed By: dberris
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D29697
llvm-svn: 295397
Summary:
The YAML output produced by llvm-xray is supposed to be wrapped at the
arbitrary default of 70 columns set by `yaml:Output`. Unfortunately,
the wrapping is rather unpredictable, and can easily go past the set
number of columns, depending on the execution environment.
To make the YAML output environment-independent, disable wrapping
instead.
Reviewers: dberris
Reviewed By: dberris
Subscribers: fhahn, llvm-commits
Differential Revision: https://reviews.llvm.org/D29962
llvm-svn: 295116
Summary:
This change implements the instrumentation map loading library which can
understand both YAML-defined instrumentation maps, and ELF 64-bit object
files that have the XRay instrumentation map section. We break it out
into a library on its own to allow for other applications to deal with
the XRay instrumentation map defined in XRay-instrumented binaries.
This type provides both raw access to the logical representation of the
instrumentation map entries as well as higher level functions for
converting a function ID into a function address.
At this point we only support ELF64 binaries and YAML-defined XRay
instrumentation maps. Future changes should extend this to support
32-bit ELF binaries, as well as other binary formats (like MachO).
As part of this change we also migrate all uses of the extraction logic
that used to be defined in tools/llvm-xray/ to use this new type and
interface for loading from files. We also remove the flag from the
`llvm-xray` tool that required users to specify the type of the
instrumentation map file being provided to instead make the library
auto-detect the file type.
Reviewers: dblaikie
Subscribers: mgorny, varno, llvm-commits
Differential Revision: https://reviews.llvm.org/D29319
llvm-svn: 293721
Summary:
In this change we move the definition of the log reading routines from
the tools directory in LLVM to {include/llvm,lib}/XRay. We improve the
documentation a little bit for the publicly accessible headers, and
adjust the top-matter. This also leads to some refactoring and cleanup
in the tooling code.
In particular, we do the following:
- Rename the class from LogReader to Trace, as it better represents
the logical set of records as opposed to a log.
- Use file type detection instead of asking the user to say what
format the input file is. This allows us to keep the interface
simple and encapsulate the logic of loading the data appropriately.
In future changes we increase the API surface and write dedicated unit
tests for the XRay library.
Depends on D24376.
Reviewers: dblaikie, echristo
Subscribers: mehdi_amini, mgorny, llvm-commits, varno
Differential Revision: https://reviews.llvm.org/D28345
llvm-svn: 291652
This is the second part of a multi-part change to define additional
subcommands to the `llvm-xray` tool.
This change defines a conversion subcommand to take XRay log files, and
turns them from one format to another (binary or YAML). This currently
only supports the first version of the log file format, defined in the
compiler-rt runtime.
Depends on D21987.
Reviewers: dblaikie, echristo
Subscribers: mehdi_amini, dberris, beanz, llvm-commits
Differential Revision: https://reviews.llvm.org/D24376
llvm-svn: 291529
