Commit Graph

9 Commits

Author SHA1 Message Date
Jonas Devlieghere 0eaee545ee [llvm] Migrate llvm::make_unique to std::make_unique
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.

llvm-svn: 369013
2019-08-15 15:54:37 +00:00
Igor Kudrin f26a70a5e7 Switch LLVM to use 64-bit offsets (2/5)
This updates all libraries and tools in LLVM Core to use 64-bit offsets
which directly or indirectly come to DataExtractor.

Differential Revision: https://reviews.llvm.org/D65638

llvm-svn: 368014
2019-08-06 10:49:40 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Dean Michael Berris da375a67f8 [XRay] Improve FDR trace handling and error messaging
Summary:
This change covers a number of things spanning LLVM and compiler-rt,
which are related in a non-trivial way.

In LLVM, we have a library that handles the FDR mode even log loading,
which uses C++'s runtime polymorphism feature to better faithfully
represent the events that are written down by the FDR mode runtime. We
do this by interpreting a trace that's serliased in a common format
agreed upon by both the trace loading library and the FDR mode runtime.
This library is under active development, which consists of features
allowing us to reconstitute a higher-level event log.

This event log is used by the conversion and visualisation tools we have
for interpreting XRay traces.

One of the tools we have is a diagnostic tool in llvm-xray called
`fdr-dump` which we've been using to debug our expectations of what the
FDR runtime should be writing and what the logical FDR event log
structures are. We use this fairly extensively to reason about why some
non-trivial traces we're generating with FDR mode runtimes fail to
convert or fail to parse correctly.

One of these failures we've found in manual debugging of some of the
traces we've seen involve an inconsistency between the buffer extents (a
record indicating how many bytes to follow are part of a logical
thread's event log) and the record of the bytes written into the log --
sometimes it turns out the data could be garbage, due to buffers being
recycled, but sometimes we're seeing the buffer extent indicating a log
is "shorter" than the actual records associated with the buffer. This
case happens particularly with function entry records with a call
argument.

This change for now updates the FDR mode runtime to write the bytes for
the function call and arg record before updating the buffer extents
atomically, allowing multiple threads to see a consistent view of the
data in the buffer using the atomic counter associated with a buffer.
What we're trying to prevent here is partial updates where we see the
intermediary updates to the buffer extents (function record size then
call argument record size) becoming observable from another thread, for
instance, one doing the serialization/flushing.

To do both diagnose this issue properly, we need to be able to honour
the extents being set in the `BufferExtents` records marking the
beginning of the logical buffers when reading an FDR trace. Since LLVM
doesn't use C++'s RTTI mechanism, we instead follow the advice in the
documentation for LLVM Style RTTI
(https://llvm.org/docs/HowToSetUpLLVMStyleRTTI.html). We then rely on
this RTTI feature to ensure that our file-based record producer (our
streaming "deserializer") can honour the extents of individual buffers
as we interpret traces.

This also sets us up to be able to eventually do smart
skipping/continuation of FDR logs, seeking instead to find BufferExtents
records in cases where we find potentially recoverable errors. In the
meantime, we make this change to operate in a strict mode when reading
logical buffers with extent records.

Reviewers: mboerger

Subscribers: hiraditya, llvm-commits, jfb

Differential Revision: https://reviews.llvm.org/D54201

llvm-svn: 346473
2018-11-09 06:26:48 +00:00
Dean Michael Berris 6b67ff0300 [XRay] Add CPU ID in Custom Event FDR Records
Summary:
This change cuts across compiler-rt and llvm, to increment the FDR log
version number to 4, and include the CPU ID in the custom event records.

This is a step towards allowing us to change the `llvm::xray::Trace`
object to start representing both custom and typed events in the stream
of records. Follow-on changes will allow us to change the kinds of
records we're presenting in the stream of traces, to incorporate the
data in custom/typed events.

A follow-on change will handle the typed event case, where it may not
fit within the 15-byte buffer for metadata records.

This work is part of the larger effort to enable writing analysis and
processing tools using a common in-memory representation of the events
found in traces. The work will focus on porting existing tools in LLVM
to use the common representation and informing the design of a
library/framework for expressing trace event analysis as C++ programs.

Reviewers: mboerger, eizan

Subscribers: hiraditya, mgrang, llvm-commits

Differential Revision: https://reviews.llvm.org/D53920

llvm-svn: 345798
2018-11-01 00:18:52 +00:00
Dean Michael Berris d2c50408d4 [XRay] Add TSC to NewCPUId Records
Summary:
This more correctly reflects the data written by the FDR mode runtime.

This is a continuation of the work in D50441.

Reviewers: mboerger, eizan

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D51911

llvm-svn: 341905
2018-09-11 06:36:51 +00:00
Dean Michael Berris 98717978c9 [XRay] Make the FDRTraceWriter Endian-aware
Before this patch, the FDRTraceWriter would not take endianness into
account when writing data into the output stream.

This is a follow-up to D51289 and D51210.

llvm-svn: 341223
2018-08-31 16:08:38 +00:00
Roman Lebedev a8c22c0894 [XRay] FDRProducerConsumerTest: unbreak (gcc?) build
/build/llvm/unittests/XRay/FDRProducerConsumerTest.cpp:90:27: error: declaration of ‘std::unique_ptr<llvm::xray::Record> llvm::xray::{anonymous}::RoundTripTest<T>::Record’ [-fpermissive]
   std::unique_ptr<Record> Record;
                           ^~~~~~
In file included from /build/llvm/include/llvm/XRay/FDRLogBuilder.h:12,
                 from /build/llvm/unittests/XRay/FDRProducerConsumerTest.cpp:15:
/build/llvm/include/llvm/XRay/FDRRecords.h:28:7: error: changes meaning of ‘Record’ from ‘class llvm::xray::Record’ [-fpermissive]
 class Record {
       ^~~~~~

llvm-svn: 341189
2018-08-31 08:59:15 +00:00
Dean Michael Berris 146d5791d9 [XRay] FDR Record Producer/Consumer Implementation
Summary:
This patch defines two new base types called `RecordProducer` and
`RecordConsumer` which have default implementations for convenience
(particularly for testing).

A `RecordProducer` implementation has one member function called
`produce()` which serves as a factory constructor for `Record`
instances. This code exercises the `RecordInitializer` code path in the
implementation for `FileBasedRecordProducer`.

A `RecordConsumer` has a single member function called `consume(...)`
which, as the name implies, consumes instances of
`std::unique_ptr<Record>`. We have two implementations, one of which is
used in the test to generate a vector of `std::unique_ptr<Record>`
similar to how the `LogBuilder` implementation works.

We introduce a test in `FDRProducerConsumerTest` which ensures that
records we write through the `FDRTraceWriter` can be loaded by the
`FileBasedRecordProducer`. The record(s) loaded this way are written
again through the `FDRTraceWriter` into a separate string, which we then
compare. This ensures that the read-in bytes to create the `Record`
instances in memory can be replicated when written out through the
`FDRTraceWriter`.

This change depends on D51210 and is part of the refactoring of D50441
into smaller, more focused changes.

Reviewers: eizan, kpw

Subscribers: mgorny, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D51289

llvm-svn: 341180
2018-08-31 08:04:56 +00:00