Summary:
Adding a new restructuredText file to document the trace format produced with
an FDR mode handler and read by llvm-xray toolset.
Fixed two problems in the documentation from differential review. One bad table
and a missing link in the toc.
Original commit was e97c5836a77db803fe53319c53f3bf8e8b26d2b7.
Reviewers: dberris, pelikan
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D36041
llvm-svn: 309891
Summary:
Adding a new restructuredText file to document the trace format produced with
an FDR mode handler and read by llvm-xray toolset.
Reviewers: dberris, pelikan
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D36041
llvm-svn: 309836
Summary:
In D30630 we will start writing custom event records. To avoid breaking
the tools that read the FDR mode records, we skip over these records.
To support these custom event records more effectively, we will have to
expose them in the trace loading API. Those changes will be forthcoming.
Reviewers: kpw, pelikan
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D33032
llvm-svn: 302856
Summary:
It is problematic for this reader that it expects to read data from
several threads, but the header or message format does not define
framing. Since the buffers are reused, we can't rely on skipping
zeroed out data as a synchronization method either.
There is an argument that this is not version compatible with the format
the reader expected previously. I argue that since the writer wrote garbage
past the end of buffer record, there is no currently working reader to
compromise.
The corresponding writer change is posted to D31384.
Reviewers: dberris, pelikan
Reviewed By: dberris
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D31385
llvm-svn: 298983
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:
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
Benjamin Kramer