Remove all older OMP spec versioning from the runtime and build system.
Patch by Terry Wilmarth
Differential Revision: https://reviews.llvm.org/D64534
llvm-svn: 365963
Added synchronization for possible concurrent initialization of mutexes
by multiple threads. The need of synchronization caused by commit r357927
which added the use of mutexes at threads movement to/from common pool
(earlier the mutexes were used only at suspend/resume).
Patch by Johnny Peyton.
Differential Revision: https://reviews.llvm.org/D61995
llvm-svn: 360919
This patch cleans up the bookkeeping code for the load balancing dynamic mode.
When a thread is moved to or from the thread pool, the th_active_in_pool flag
and the __kmp_thread_pool_active_nth global counter are both updated. This
removes the need for the corrective code in the main wait loop. Another global
counter, __kmp_thread_pool_nth, was removed completely, as it was only used for
debugging, but was not under KMP_DEBUG.
Patch by Terry Wilmarth
Differential Revision: https://reviews.llvm.org/D59508
llvm-svn: 357927
Debug dump on large machine shows when many OpenMP threads (401 in total)
sleep on a barrier, one of the innermost nesting levels sleeps
on a child's b_arrived flag whose value is equal to 4 and is equal to
checker value. i.e., (1) sleep bit is 0, and (2) done_check() would
return true if called.
It is unclear how this might happen. It could be Windows Server 2016's
error of EnterCriticalSection / LeaveCriticalSection, or
error of WaitForSingleObject / SetEvent / ResetEvent, or
error in the library which is very difficult to find.
As a workaround, change INFINITE wait to timed wait, so that each
thread awakens each 5 seconds (the timeout was chosen arbitrary to not
disturb other threads much), check flag condition under the lock, and
either go to sleep again or stop sleeping as a result of the check.
Patch by Andrey Churbanov
Differential Revision: https://reviews.llvm.org/D59793
llvm-svn: 357722
This patch cleans up the yielding code and makes it optional. An
environment variable, KMP_USE_YIELD, was added. Yielding is still
on by default (KMP_USE_YIELD=1), but can be turned off completely
(KMP_USE_YIELD=0), or turned on only when oversubscription is detected
(KMP_USE_YIELD=2). Note that oversubscription cannot always be detected
by the runtime (for example, when the runtime is initialized and the
process forks, oversubscription cannot be detected currently over
multiple instances of the runtime).
Because yielding can be controlled by user now, the library mode
settings (from KMP_LIBRARY) for throughput and turnaround have been
adjusted by altering blocktime, unless that was also explicitly set.
In the original code, there were a number of places where a double yield
might have been done under oversubscription. This version checks
oversubscription and if that's not going to yield, then it does
the spin check.
Patch by Terry Wilmarth
Differential Revision: https://reviews.llvm.org/D58148
llvm-svn: 355120
to reflect the new license. These used slightly different spellings that
defeated my regular expressions.
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: 351648
Add omp_pause_resource and omp_pause_resource_all API and enum, plus stub for
internal implementation. Implemented callable helper function to do local pause,
and added basic functionality for hard and soft pause.
Patch by Terry Wilmarth
Differential Revision: https://reviews.llvm.org/D55078
llvm-svn: 351372
These are preliminary changes that attempt to use C++11 Atomics in the runtime.
We are expecting better portability with this change across architectures/OSes.
Here is the summary of the changes.
Most variables that need synchronization operation were converted to generic
atomic variables (std::atomic<T>). Variables that are updated with combined CAS
are packed into a single atomic variable, and partial read/write is done
through unpacking/packing
Patch by Hansang Bae
Differential Revision: https://reviews.llvm.org/D47903
llvm-svn: 336563
Removes semicolons after if {} blocks, function definitions, etc.
I was able to apply the large OMPT patch cleanly on top of this one
with no conflicts.
llvm-svn: 314340
Minor code cleanup of Klocwork issues. Fatal messages are given no return
attribute. Define and use KMP_NORETURN to work for multiple C++ versions.
Patch by Terry Wilmarth
Differential Revision: https://reviews.llvm.org/D37275
llvm-svn: 312538
While importing libomp into the FreeBSD base system we encountered
Clang warnings that "'register' storage class specifier is deprecated
and incompatible with C++1z [-Wdeprecated-register]".
Differential Revision: https://reviews.llvm.org/D35124
llvm-svn: 307441
This patch contains the clang-format and cleanup of the entire code base. Some
of clang-formats changes made the code look worse in places. A best effort was
made to resolve the bulk of these problems, but many remain. Most of the
problems were mangling line-breaks and tabbing of comments.
Patch by Terry Wilmarth
Differential Revision: https://reviews.llvm.org/D32659
llvm-svn: 302929
