Currently it is hard to avoid having LLVM link to the system install of
ncurses, since it uses check_library_exists to find e.g. libtinfo and
not find_library or find_package.
With this change the ncurses lib is found with find_library, which also
considers CMAKE_PREFIX_PATH. This solves an issue for the spack package
manager, where we want to use the zlib installed by spack, and spack
provides the CMAKE_PREFIX_PATH for it.
This is a similar change as https://reviews.llvm.org/D79219, which just
landed in master.
Patch By: haampie
Differential Revision: https://reviews.llvm.org/D85820
The introduction of find_library for ncurses caused more issues than it solved problems. The current open issue is it makes the static build of LLVM fail. It is better to revert for now, and get back to it later.
Revert "[CMake] Fix an issue where get_system_libname creates an empty regex capture on windows"
This reverts commit 1ed1e16ab8.
Revert "Fix msan build"
This reverts commit 34fe9613dd.
Revert "[CMake] Always mark terminfo as unavailable on Windows"
This reverts commit 76bf26236f.
Revert "[CMake] Fix OCaml build failure because of absolute path in system libs"
This reverts commit 8e4acb82f7.
Revert "[CMake] Don't look for terminfo libs when LLVM_ENABLE_TERMINFO=OFF"
This reverts commit 495f91fd33.
Revert "Use find_library for ncurses"
This reverts commit a52173a3e5.
Differential revision: https://reviews.llvm.org/D86521
Currently it is hard to avoid having LLVM link to the system install of
ncurses, since it uses check_library_exists to find e.g. libtinfo and
not find_library or find_package.
With this change the ncurses lib is found with find_library, which also
considers CMAKE_PREFIX_PATH. This solves an issue for the spack package
manager, where we want to use the zlib installed by spack, and spack
provides the CMAKE_PREFIX_PATH for it.
This is a similar change as https://reviews.llvm.org/D79219, which just
landed in master.
Differential revision: https://reviews.llvm.org/D85820
The X-ray unit tests in compiler-rt are overriding the C++ version by
explicitly passing -std=c++11 in the compiler invocation. This poses a
problem as these tests are including LLVM headers that can now use C++14
features. I'm temporarily reverting this as I investigate the correct
solution.
llvm-svn: 368952
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.
Differential revision: https://reviews.llvm.org/D66259
llvm-svn: 368946
Add missed value "libcxxabi" and introduce SANITIZER_TEST_CXX for linking
unit tests. This needs to be a full C++ library and cannot be libcxxabi.
Recommit r354132 which I reverted in r354153 because it broke a sanitizer
bot. This was because of the "fixes" for pthread linking, so I've removed
these changes.
Differential Revision: https://reviews.llvm.org/D58012
llvm-svn: 354198
Add missed value "libcxxabi" and introduce SANITIZER_TEST_CXX for linking
unit tests. This needs to be a full C++ library and cannot be libcxxabi.
Differential Revision: https://reviews.llvm.org/D58012
llvm-svn: 354132
Summary:
A link error was encountered when using the Red Hat Developer Toolset.
In the RHDTS, `libstdc++.so` is a linker script that may resolve symbols
to a static library. This patch places `-lstdc++` later in the ordering.
Reviewers: sfertile, nemanjai, tstellar, dberris
Reviewed By: dberris
Subscribers: dberris, mgorny, delcypher, jdoerfert, #sanitizers, llvm-commits
Tags: #llvm, #sanitizers
Differential Revision: https://reviews.llvm.org/D58144
llvm-svn: 353905
Summary:
As reported on llvm-testers, during 8.0.0-rc1 testing I got errors while
building of `XRayTest`, during `check-all`:
```
[100%] Generating XRayTest-x86_64-Test
/home/dim/llvm/8.0.0/rc1/Phase3/Release/llvmCore-8.0.0-rc1.obj/./lib/libLLVMSupport.a(Signals.cpp.o): In function `llvm::sys::PrintStackTrace(llvm::raw_ostream&)':
Signals.cpp:(.text._ZN4llvm3sys15PrintStackTraceERNS_11raw_ostreamE+0x24): undefined reference to `backtrace'
Signals.cpp:(.text._ZN4llvm3sys15PrintStackTraceERNS_11raw_ostreamE+0x254): undefined reference to `llvm::itaniumDemangle(char const*, char*, unsigned long*, int*)'
clang-8: error: linker command failed with exit code 1 (use -v to see invocation)
gmake[3]: *** [projects/compiler-rt/lib/xray/tests/unit/CMakeFiles/TXRayTest-x86_64-Test.dir/build.make:73: projects/compiler-rt/lib/xray/tests/unit/XRayTest-x86_64-Test] Error 1
gmake[3]: Target 'projects/compiler-rt/lib/xray/tests/unit/CMakeFiles/TXRayTest-x86_64-Test.dir/build' not remade because of errors.
gmake[2]: *** [CMakeFiles/Makefile2:33513: projects/compiler-rt/lib/xray/tests/unit/CMakeFiles/TXRayTest-x86_64-Test.dir/all] Error 2
gmake[2]: Target 'CMakeFiles/check-all.dir/all' not remade because of errors.
gmake[1]: *** [CMakeFiles/Makefile2:737: CMakeFiles/check-all.dir/rule] Error 2
gmake[1]: Target 'check-all' not remade because of errors.
gmake: *** [Makefile:277: check-all] Error 2
[Release Phase3] check-all failed
```
This is because the `backtrace` function requires `-lexecinfo` on BSD
platforms. To fix this, detect the `execinfo` library in
`cmake/config-ix.cmake`, and add it to the unit test link flags.
Additionally, since the code in `sys::PrintStackTrace` makes use of
`itaniumDemangle`, also add `-lLLVMDemangle`. (Note that this is more
of a general problem with libLLVMSupport, but I'm looking for a quick
fix now so it can be merged to the 8.0 branch.)
Reviewers: dberris, hans, mgorny, samsonov
Reviewed By: dberris
Subscribers: krytarowski, delcypher, erik.pilkington, #sanitizers, emaste, llvm-commits
Differential Revision: https://reviews.llvm.org/D57181
llvm-svn: 352234
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
Add a code to properly test for presence of LLVMTestingSupport library
when performing a stand-alone build, and skip tests requiring it when
it is not present. Since the library is not installed, llvm-config
reported empty --libs for it and the tests failed to link with undefined
references. Skipping the two fdr_* test files is better than failing to
build, and should be good enough until we find a better solution.
NB: both installing LLVMTestingSupport and building it automatically
from within compiler-rt sources are non-trivial. The former due to
dependency on gtest, the latter due to tight integration with LLVM
source tree.
Differential Revision: https://reviews.llvm.org/D55891
llvm-svn: 349899
Summary:
This change builds upon D54989, which removes memory allocation from the
critical path of the profiling implementation. This also changes the API
for the profile collection service, to take ownership of the memory and
associated data structures per-thread.
The consolidation of the memory allocation allows us to do two things:
- Limits the amount of memory used by the profiling implementation,
associating preallocated buffers instead of allocating memory
on-demand.
- Consolidate the memory initialisation and cleanup by relying on the
buffer queue's reference counting implementation.
We find a number of places which also display some problematic
behaviour, including:
- Off-by-factor bug in the allocator implementation.
- Unrolling semantics in cases of "memory exhausted" situations, when
managing the state of the function call trie.
We also add a few test cases which verify our understanding of the
behaviour of the system, with important edge-cases (especially for
memory-exhausted cases) in the segmented array and profile collector
unit tests.
Depends on D54989.
Reviewers: mboerger
Subscribers: dschuff, mgorny, dmgreen, jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D55249
llvm-svn: 348568
This reverts commit r348455, with some additional changes:
- Work-around deficiency of gcc-4.8 by duplicating the implementation of
`AppendEmplace` in `Append`, but instead of using brace-init for the
copy construction, use a placement new explicitly calling the copy
constructor.
llvm-svn: 348563
Continuation of D54989.
Additional changes:
- Use `.AppendEmplace(...)` instead of `.Append(Type{...})` to appease
GCC 4.8 with confusion on when an initializer_list is used as
opposed to a temporary aggregate initialized object.
llvm-svn: 348438
.. and also the follow-ups r348336 r348338.
It broke stand-alone compiler-rt builds with GCC 4.8:
In file included from /work/llvm/projects/compiler-rt/lib/xray/xray_function_call_trie.h:20:0,
from /work/llvm/projects/compiler-rt/lib/xray/xray_profile_collector.h:21,
from /work/llvm/projects/compiler-rt/lib/xray/xray_profile_collector.cc:15:
/work/llvm/projects/compiler-rt/lib/xray/xray_segmented_array.h: In instantiation of ‘T* __xray::Array<T>::AppendEmplace(Args&& ...) [with Args = {const __xray::FunctionCallTrie::mergeInto(__xray::FunctionCallTrie&) const::NodeAndTarget&}; T = __xray::FunctionCallTrie::mergeInto(__xray::FunctionCallTrie&) const::NodeAndTarget]’:
/work/llvm/projects/compiler-rt/lib/xray/xray_segmented_array.h:383:71: required from ‘T* __xray::Array<T>::Append(const T&) [with T = __xray::FunctionCallTrie::mergeInto(__xray::FunctionCallTrie&) const::NodeAndTarget]’
/work/llvm/projects/compiler-rt/lib/xray/xray_function_call_trie.h:517:54: required from here
/work/llvm/projects/compiler-rt/lib/xray/xray_segmented_array.h:378:5: error: could not convert ‘{std::forward<const __xray::FunctionCallTrie::mergeInto(__xray::FunctionCallTrie&) const::NodeAndTarget&>((* & args#0))}’ from ‘<brace-enclosed initializer list>’ to ‘__xray::FunctionCallTrie::mergeInto(__xray::FunctionCallTrie&) const::NodeAndTarget’
new (AlignedOffset) T{std::forward<Args>(args)...};
^
/work/llvm/projects/compiler-rt/lib/xray/xray_segmented_array.h: In instantiation of ‘T* __xray::Array<T>::AppendEmplace(Args&& ...) [with Args = {const __xray::profileCollectorService::{anonymous}::ThreadTrie&}; T = __xray::profileCollectorService::{anonymous}::ThreadTrie]’:
/work/llvm/projects/compiler-rt/lib/xray/xray_segmented_array.h:383:71: required from ‘T* __xray::Array<T>::Append(const T&) [with T = __xray::profileCollectorService::{anonymous}::ThreadTrie]’
/work/llvm/projects/compiler-rt/lib/xray/xray_profile_collector.cc:98:34: required from here
/work/llvm/projects/compiler-rt/lib/xray/xray_segmented_array.h:378:5: error: could not convert ‘{std::forward<const __xray::profileCollectorService::{anonymous}::ThreadTrie&>((* & args#0))}’ from
‘<brace-enclosed initializer list>’ to ‘__xray::profileCollectorService::{anonymous}::ThreadTrie’
/work/llvm/projects/compiler-rt/lib/xray/xray_segmented_array.h: In instantiation of ‘T* __xray::Array<T>::AppendEmplace(Args&& ...) [with Args = {const __xray::profileCollectorService::{anonymous}::ProfileBuffer&}; T = __xray::profileCollectorService::{anonymous}::ProfileBuffer]’:
/work/llvm/projects/compiler-rt/lib/xray/xray_segmented_array.h:383:71: required from ‘T* __xray::Array<T>::Append(const T&) [with T = __xray::profileCollectorService::{anonymous}::ProfileBuffer]
’
/work/llvm/projects/compiler-rt/lib/xray/xray_profile_collector.cc:244:44: required from here
/work/llvm/projects/compiler-rt/lib/xray/xray_segmented_array.h:378:5: error: could not convert ‘{std::forward<const __xray::profileCollectorService::{anonymous}::ProfileBuffer&>((* & args#0))}’ from ‘<brace-enclosed initializer list>’ to ‘__xray::profileCollectorService::{anonymous}::ProfileBuffer’
> Summary:
> This change makes the allocator and function call trie implementations
> move-aware and remove the FunctionCallTrie's reliance on a
> heap-allocated set of allocators.
>
> The change makes it possible to always have storage associated with
> Allocator instances, not necessarily having heap-allocated memory
> obtainable from these allocator instances. We also use thread-local
> uninitialised storage.
>
> We've also re-worked the segmented array implementation to have more
> precondition and post-condition checks when built in debug mode. This
> enables us to better implement some of the operations with surrounding
> documentation as well. The `trim` algorithm now has more documentation
> on the implementation, reducing the requirement to handle special
> conditions, and being more rigorous on the computations involved.
>
> In this change we also introduce an initialisation guard, through which
> we prevent an initialisation operation from racing with a cleanup
> operation.
>
> We also ensure that the ThreadTries array is not destroyed while copies
> into the elements are still being performed by other threads submitting
> profiles.
>
> Note that this change still has an issue with accessing thread-local
> storage from signal handlers that are instrumented with XRay. We also
> learn that with the testing of this patch, that there will be cases
> where calls to mmap(...) (through internal_mmap(...)) might be called in
> signal handlers, but are not async-signal-safe. Subsequent patches will
> address this, by re-using the `BufferQueue` type used in the FDR mode
> implementation for pre-allocated memory segments per active, tracing
> thread.
>
> We still want to land this change despite the known issues, with fixes
> forthcoming.
>
> Reviewers: mboerger, jfb
>
> Subscribers: jfb, llvm-commits
>
> Differential Revision: https://reviews.llvm.org/D54989
llvm-svn: 348346
Summary:
This change makes the allocator and function call trie implementations
move-aware and remove the FunctionCallTrie's reliance on a
heap-allocated set of allocators.
The change makes it possible to always have storage associated with
Allocator instances, not necessarily having heap-allocated memory
obtainable from these allocator instances. We also use thread-local
uninitialised storage.
We've also re-worked the segmented array implementation to have more
precondition and post-condition checks when built in debug mode. This
enables us to better implement some of the operations with surrounding
documentation as well. The `trim` algorithm now has more documentation
on the implementation, reducing the requirement to handle special
conditions, and being more rigorous on the computations involved.
In this change we also introduce an initialisation guard, through which
we prevent an initialisation operation from racing with a cleanup
operation.
We also ensure that the ThreadTries array is not destroyed while copies
into the elements are still being performed by other threads submitting
profiles.
Note that this change still has an issue with accessing thread-local
storage from signal handlers that are instrumented with XRay. We also
learn that with the testing of this patch, that there will be cases
where calls to mmap(...) (through internal_mmap(...)) might be called in
signal handlers, but are not async-signal-safe. Subsequent patches will
address this, by re-using the `BufferQueue` type used in the FDR mode
implementation for pre-allocated memory segments per active, tracing
thread.
We still want to land this change despite the known issues, with fixes
forthcoming.
Reviewers: mboerger, jfb
Subscribers: jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D54989
llvm-svn: 348335
Use a more representative test of allocating small chunks for
oddly-sized (small) objects from an allocator that has a page's worth of
memory.
llvm-svn: 347286
Summary:
This change addresses an issue which shows up with the synchronised race
between threads writing into a buffer, and another thread reading the
buffer.
In a lot of cases, we cannot guarantee that threads will always see the
signal to finalise their buffers in time despite the grace periods and
state machine maintained through atomic variables. This change addresses
it by ensuring that the same instance being updated to indicate how much
of the buffer is "used" by the writing thread is the same instance being
read by the thread processing the buffer to be written out to disk or
handled through the iterators.
To do this, we ensure that all the "extents" instances live in their own
the backing store, in a different contiguous page from the
buffer-specific backing store. We also take precautions to ensure that
the atomic variables are cache-line-sized to prevent false-sharing from
unnecessarily causing cache contention on unrelated writes/reads.
It's feasible that we may in the future be able to move the storage of
the extents objects into the single backing store, slightly changing the
way to compute the size(s) of the buffers, but in the meantime we'll
settle for the isolation afforded by having a different backing store
for the extents instances.
Reviewers: mboerger
Subscribers: jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D54684
llvm-svn: 347280
Summary:
Before this change, we could run into a situation where we may try to
undo tail exit records after writing metadata records before a function
enter event. This change rectifies that by resetting the tail exit
counter after writing the metadata records.
Reviewers: mboerger
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D54292
llvm-svn: 346475
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
Summary:
This change cuts across LLVM and compiler-rt to add support for
rendering custom events in the XRayRecord type, to allow for including
user-provided annotations in the output YAML (as raw bytes).
This work enables us to add custom event and typed event records into
the `llvm::xray::Trace` type for user-provided events. This can then be
programmatically handled through the C++ API and can be included in some
of the tooling as well. For now we support printing the raw data we
encounter in the custom events in the converted output.
Future work will allow us to start interpreting these custom and typed
events through a yet-to-be-defined API for extending the trace analysis
library.
Reviewers: mboerger
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D54139
llvm-svn: 346214
Summary:
Prior to this change, we can run into situations where the TSC we're
getting when exiting a function is less than the TSC we got when
entering it. This would sometimes cause the counter for cumulative call
times overflow, which was erroneously also being stored as a signed
64-bit integer.
This change addresses both these issues while adding provisions for
tracking CPU migrations. We do this because moving from one CPU to
another doesn't guarantee that the timestamp counter for some
architectures aren't guaranteed to be synchronised. For the moment, we
leave the provisions there until we can update the data format to
include the counting of CPU migrations we can catch.
We update the necessary tests as well, ensuring that our expectations
for the cycle accounting to be met in case of counter wraparound.
Reviewers: mboerger
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D54088
llvm-svn: 346116
Summary:
Fix some issues discovered from mostly manual inspection of outputs from
the `llvm-xray fdr-dump` tool.
It turns out we haven't been writing the deltas properly, and have been
writing down zeros for deltas of some records. This change fixes this
oversight born by the recent refactoring.
Reviewers: mboerger
Subscribers: llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D54022
llvm-svn: 345954
Summary:
This is a follow-on change to D53858 which turns out to have had a TSC
accounting bug when writing out function exit records in FDR mode.
This change adds a number of tests to ensure that:
- We are handling the delta between the exit TSC and the last TSC we've
seen.
- We are writing the custom event and typed event records as a single
update to the buffer extents.
- We are able to catch boundary conditions when loading FDR logs.
We introduce a TSC matcher to the test helpers, which we use in the
testing/verification of the TSC accounting change.
Reviewers: mboerger
Subscribers: mgorny, hiraditya, jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D53967
llvm-svn: 345905
Summary:
In D53560, we assumed a specific layout for memory without using an
explicit structure. This follow-up change uses more portable layout
control by using unions in a struct, and consolidating the memory
management code in the buffer queue.
We also take the opportunity to improve the documentation on the types
and operations, along with simplifying some of the logic in the buffer
queue implementation.
Reviewers: mboerger, eizan
Subscribers: jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D53802
llvm-svn: 345485
Summary:
This is an intermediary step in the full support for generational buffer
management in the FDR runtime. This change makes the FDR controller
aware of the new generation number in the buffers handed out by the
BufferQueue type.
In the process of making this change, we've realised that the cleanest
way of ensuring that the backing store per generation is live while all
the threads that need access to it will need reference counting to tie
the backing store to the lifetime of all threads that have a handle on
buffers associated with the memory.
We also learn that we're missing the edge-case in the function exit
handler's implementation where the first record being written into the
buffer is a function exit, which is caught/fixed by the test for
generational buffer management.
We still haven't wired the controller into the FDR mode runtime, which
will need the reference counting on the backing store implemented to
ensure that we're being conservatively thread-safe with this approach.
Depends on D52974.
Reviewers: mboerger, eizan
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D53551
llvm-svn: 345445
Summary:
This change updates the buffer queue implementation to support using a
generation number to identify the lifetime of buffers. This first part
introduces the notion of the generation number, without changing the way
we handle the buffers yet.
What's missing here is the cleanup of the buffers. Ideally we'll keep
the two most recent generations. We need to ensure that before we do any
writes to the buffers, that we check the generation number(s) first.
Those changes will follow-on from this change.
Depends on D52588.
Reviewers: mboerger, eizan
Subscribers: llvm-commits, jfb
Differential Revision: https://reviews.llvm.org/D52974
llvm-svn: 344881
Summary:
This change allows us to handle allocator exhaustion properly in the
segmented array implementation. Before this change, we relied on the
caller of the `trim` function to provide a valid number of elements to
trim. This change allows us to do the right thing in case the elements
to trim is greater than the size of the container.
Reviewers: mboerger, eizan
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D53484
llvm-svn: 344880
Summary:
This change updates the buffer queue implementation to support using a
generation number to identify the lifetime of buffers. This first part
introduces the notion of the generation number, without changing the way
we handle the buffers yet.
What's missing here is the cleanup of the buffers. Ideally we'll keep
the two most recent generations. We need to ensure that before we do any
writes to the buffers, that we check the generation number(s) first.
Those changes will follow-on from this change.
Depends on D52588.
Reviewers: mboerger, eizan
Subscribers: llvm-commits, jfb
Differential Revision: https://reviews.llvm.org/D52974
llvm-svn: 344670
Summary:
This change implements a controller for abstracting away the details of
what happens when tracing with FDR mode. This controller type allows us
to test in isolation the various cases where we're encountering function
entry, exit, and other kinds of events we are handling when FDR mode is
enabled.
This change introduces a number of testing facilities we've needed to
better support expressing the conditions we need for the unit tests. We
leave some TODOs for moving those utilities into the LLVM project,
sitting in the `Testing` library, to make matching conditions on XRay
`Trace` instances through googlemock more manageable and declarative.
We don't wire in the controller right away, to allow us to incrementally
update the implementation(s) as we increase testing coverage of the
controller type. There's a need to re-think the way we're managing
buffers in a multi-threaded environment, which is more invasive than
this implementation.
This step in the process allows us to encode our assumptions in the
implementation of the controller, and then evolve the buffer queue
implementation to support generational buffer management to ensure we
can continue to support the cases we're already supporting with the
controller.
Reviewers: mboerger, eizan
Subscribers: mgorny, llvm-commits, jfb
Differential Revision: https://reviews.llvm.org/D52588
llvm-svn: 344488
Summary:
This change allows us to use the library path from which the LLVM
libraries are installed, in case the LLVM installation generates shared
libraries.
This should address llvm.org/PR39070.
Reviewers: mboerger, eizan
Subscribers: mgorny, jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D52597
llvm-svn: 343280
Summary:
This change spans both LLVM and compiler-rt, where we do the following:
- Add XRay to the LLVMBuild system, to allow for distributing the XRay
trace loading library along with the LLVM distributions.
- Use `llvm-config` better in the compiler-rt XRay implementation, to
depend on the potentially already-distributed LLVM XRay library.
While this is tested with the standalone compiler-rt build, it does
require that the LLVMXRay library (and LLVMSupport as well) are
available during the build. In case the static libraries are available,
the unit tests will build and work fine. We're still having issues with
attempting to use a shared library version of the LLVMXRay library since
the shared library might not be accessible from the standard shared
library lookup paths.
The larger change here is the inclusion of the LLVMXRay library in the
distribution, which allows for building tools around the XRay traces and
profiles that the XRay runtime already generates.
Reviewers: echristo, beanz
Subscribers: mgorny, hiraditya, mboerger, llvm-commits
Differential Revision: https://reviews.llvm.org/D52349
llvm-svn: 342859
Summary:
This change introduces an `FDRLogWriter` type which is responsible for
serialising metadata and function records to character buffers. This is
the first step in a refactoring of the implementation of the FDR runtime
to allow for more granular testing of the individual components of the
implementation.
The main contribution of this change is a means of hiding the details of
how specific records are written to a buffer, and for managing the
extents of these buffers. We make use of C++ features (templates and
some metaprogramming) to reduce repetition in the act of writing out
specific kinds of records to the buffer.
In this process, we make a number of changes across both LLVM and
compiler-rt to allow us to use the `Trace` abstraction defined in the
LLVM project in the testing of the runtime implementation. This gives us
a closer end-to-end test which version-locks the runtime implementation
with the loading implementation in LLVM.
We also allow using gmock in compiler-rt unit tests, by adding the
requisite definitions in the `AddCompilerRT.cmake` module. We also add
the terminfo library detection along with inclusion of the appropriate
compiler flags for header include lookup.
Finally, we've gone ahead and updated the FDR logging implementation to
use the FDRLogWriter for the lowest-level record-writing details.
Following patches will isolate the state machine transitions which
manage the set-up and tear-down of the buffers we're using in multiple
threads.
Reviewers: mboerger, eizan
Subscribers: mgorny, jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D52220
llvm-svn: 342617
Instead of assuming `-ltinfo` works, check whether there's terminfo
support on the host where LLVMSupport is compiled.
Follow-up to D52220.
llvm-svn: 342523
Summary:
This change introduces an `FDRLogWriter` type which is responsible for
serialising metadata and function records to character buffers. This is
the first step in a refactoring of the implementation of the FDR runtime
to allow for more granular testing of the individual components of the
implementation.
The main contribution of this change is a means of hiding the details of
how specific records are written to a buffer, and for managing the
extents of these buffers. We make use of C++ features (templates and
some metaprogramming) to reduce repetition in the act of writing out
specific kinds of records to the buffer.
In this process, we make a number of changes across both LLVM and
compiler-rt to allow us to use the `Trace` abstraction defined in the
LLVM project in the testing of the runtime implementation. This gives us
a closer end-to-end test which version-locks the runtime implementation
with the loading implementation in LLVM.
We also allow using gmock in compiler-rt unit tests, by adding the
requisite definitions in the `AddCompilerRT.cmake` module.
Finally, we've gone ahead and updated the FDR logging implementation to
use the FDRLogWriter for the lowest-level record-writing details.
Following patches will isolate the state machine transitions which
manage the set-up and tear-down of the buffers we're using in multiple
threads.
Reviewers: mboerger, eizan
Subscribers: mgorny, jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D52220
llvm-svn: 342518
This API has been deprecated three months ago and shouldn't be used
anymore, all clients should migrate to the new string based API.
Differential Revision: https://reviews.llvm.org/D51606
llvm-svn: 342318
Summary:
This change provides access to the file header even in the in-memory
buffer processing. This allows in-memory processing of the buffers to
also check the version, and the format, of the profile data.
Reviewers: eizan, kpw
Reviewed By: eizan
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D50037
llvm-svn: 338347
Summary:
This is a follow-on to D49217 which simplifies and optimises the
implementation of the segmented array. In this patch we co-locate the
book-keeping for segments in the `__xray::Array<T>` with the data it's
managing. We take the chance in this patch to actually rename `Chunk` to
`Segment` to better align with the high-level description of the
segmented array.
With measurements using benchmarks landed in D48879, we've identified
that calls to `pthread_getspecific` started dominating the cycles, which
led us to revert the change made in D49217 to use C++ thread_local
initialisation instead (it reduces the cost by a huge margin, since we
save one PLT-based call to pthread functions in the hot path). In
particular, this is in `__xray::getThreadLocalData()`.
We also took the opportunity to remove the least-common-multiple based
calculation and instead pack as much data into segments of the array.
This greatly simplifies the API of the container which hides as much of
the implementation details as possible. For instance, we calculate the
number of elements we need for the each segment internally in the Array
instead of making it part of the type.
With the changes here, we're able to get a measurable improvement on the
performance of profiling mode on top of what D48879 already provides.
Depends on D48879.
Reviewers: kpw, eizan
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D49363
llvm-svn: 337343
Summary:
This change simplifies the XRay Allocator implementation to self-manage
an mmap'ed memory segment instead of using the internal allocator
implementation in sanitizer_common.
We've found through benchmarks and profiling these benchmarks in D48879
that using the internal allocator in sanitizer_common introduces a
bottleneck on allocating memory through a central spinlock. This change
allows thread-local allocators to eliminate contention on the
centralized allocator.
To get the most benefit from this approach, we also use a managed
allocator for the chunk elements used by the segmented array
implementation. This gives us the chance to amortize the cost of
allocating memory when creating these internal segmented array data
structures.
We also took the opportunity to remove the preallocation argument from
the allocator API, simplifying the usage of the allocator throughout the
profiling implementation.
In this change we also tweak some of the flag values to reduce the
amount of maximum memory we use/need for each thread, when requesting
memory through mmap.
Depends on D48956.
Reviewers: kpw, eizan
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D49217
llvm-svn: 337342
Summary:
Fix a TODO in CMake config for XRay tests to use the detected C++ ABI
library in the tests.
Also make the tests depend on the llvm-xray target when built in-tree.
Reviewers: kpw, eizan
Reviewed By: eizan
Subscribers: mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D49358
llvm-svn: 337142
Summary:
llvm-xray changes:
- account-mode - process-id {...} shows after thread-id
- convert-mode - process {...} shows after thread
- parses FDR and basic mode pid entries
- Checks version number for FDR log parsing.
Basic logging changes:
- Update header version from 2 -> 3
FDR logging changes:
- Update header version from 2 -> 3
- in writeBufferPreamble, there is an additional PID Metadata record (after thread id record and tsc record)
Test cases changes:
- fdr-mode.cc, fdr-single-thread.cc, fdr-thread-order.cc modified to catch process id output in the log.
Reviewers: dberris
Reviewed By: dberris
Subscribers: hiraditya, llvm-commits, #sanitizers
Differential Revision: https://reviews.llvm.org/D49153
llvm-svn: 336974
Petr Hosek