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* [OpenMP] NFC: Fix trivial typos in commentsKazuaki Ishizaki2020-01-071-1/+1
| | | | | | | | | | | | Reviewers: jdoerfert, Jim Reviewed By: Jim Subscribers: Jim, mgorny, guansong, jfb, openmp-commits Tags: #openmp Differential Revision: https://reviews.llvm.org/D72285
* [OpenMP] Remove 'unnecessary parentheses'Jonas Hahnfeld2019-08-151-8/+8
| | | | | | | | | | The variables in kmp_lock.cpp are really arrays of function pointers that return void or int, not pointers to functions that return void* or int*. The other changes are only cosmetic. Differential Revision: https://reviews.llvm.org/D65870 llvm-svn: 369002
* [OpenMP] Make use of sched_yield optional in runtimeJonathan Peyton2019-02-281-30/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | 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
* Update more file headers across all of the LLVM projects in the monorepoChandler Carruth2019-01-191-4/+3
| | | | | | | | | | | | | | | | | | 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
* [OpenMP] Fixes for LIBOMP_OMP_VERSION=45/40Roman Lebedev2018-12-151-8/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: I have discovered this because i wanted to experiment with building static libomp (with openmp-4.0 support only) for debugging purposes. There are three kinds of problems here: 1. `__kmp_compare_and_store_acq()` simply does not exist. It was added in D47903 by @jlpeyton. I'm guessing `__kmp_atomic_compare_store_acq()` was meant. 2. In `__kmp_is_ticket_lock_initialized()`, `lck->lk.initialized` is `std::atomic<bool>`, while `lck` is `kmp_ticket_lock_t *`. Naturally, they can't be equality-compared. Either, it should return the value read from `lck->lk.initialized`, or do what `__kmp_is_queuing_lock_initialized()` does, compare the passed pointer with the field in the struct pointed by the pointer. I think the latter is correct-er choice here. 3. Tests were not versioned. They assume that `LIBOMP_OMP_VERSION` is at the latest version. This does not touch LIBOMP_OMP_VERSION=30. That is still broken. Reviewers: jlpeyton, Hahnfeld, AndreyChurbanov Reviewed By: AndreyChurbanov Subscribers: guansong, jfb, openmp-commits, jlpeyton Tags: #openmp Differential Revision: https://reviews.llvm.org/D55496 llvm-svn: 349260
* [OpenMP] Cleanup codeJonathan Peyton2018-08-091-2/+2
| | | | | | | | | | | | | | | | This patch cleans up unused functions, variables, sign compare issues, and addresses some -Warning flags which are now enabled including -Wcast-qual. Not all the warning flags in LibompHandleFlags.cmake are enabled, but some are with this patch. Some __kmp_gtid_from_* macros in kmp.h are switched to static inline functions which allows us to remove the awkward definition of KMP_DEBUG_ASSERT() and KMP_ASSERT() macros which used the comma operator. This had to be done for the innumerable -Wunused-value warnings related to KMP_DEBUG_ASSERT() Differential Revision: https://reviews.llvm.org/D49105 llvm-svn: 339393
* [OpenMP] Use C++11 Atomics - barrier, tasking, and lock codeJonathan Peyton2018-07-091-16/+18
| | | | | | | | | | | | | | | | | 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
* Minor code cleanupJonathan Peyton2018-01-101-2/+2
| | | | | | | | Patch by Terry Wilmarth Differential Revision: https://reviews.llvm.org/D41831 llvm-svn: 322203
* Fix trademarks found by scannerJonathan Peyton2018-01-041-2/+2
| | | | llvm-svn: 321827
* Update implementation of OMPT to the specification OpenMP 5.0 Preview 1 (TR4).Joachim Protze2017-11-011-2/+2
| | | | | | | | | | | | | | The code is tested to work with latest clang, GNU and Intel compiler. The implementation is optimized for low overhead when no tool is attached shifting the cost to execution with tool attached. This patch does not implement OMPT for libomptarget. Patch by Simon Convent and Joachim Protze Differential Revision: https://reviews.llvm.org/D38185 llvm-svn: 317085
* Apply formatting changesJonathan Peyton2017-10-201-2/+0
| | | | | | | | | | .clang-format's comments are removed and a (hopefully) final set of formatting changes are applied. Differential Revision: https://reviews.llvm.org/D38837 Differential Revision: https://reviews.llvm.org/D38920 llvm-svn: 316227
* Fix static initializers for locks.Jonathan Peyton2017-06-061-4/+5
| | | | | | | | | | | Fix static initializers to use the proper unlocked value for the poll field of the tas and futex locks. Patch by Terry Wilmarth Differential Revision: https://reviews.llvm.org/D33794 llvm-svn: 304828
* Clang-format and whitespace cleanup of source codeJonathan Peyton2017-05-121-764/+739
| | | | | | | | | | | | | 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
* Follow up to r289732: Update comments in source files to reference .cpp filesJonathan Peyton2016-12-141-1/+1
| | | | | | Patch by Hansang Bae llvm-svn: 289739
* Apply the KMP_USE_FUTEX feature macro everywhereJonathan Peyton2016-06-221-7/+8
| | | | llvm-svn: 273438
* Renaming change: 41 -> 45 and 4.1 -> 4.5Jonathan Peyton2016-06-141-1/+1
| | | | | | | | OpenMP 4.1 is now OpenMP 4.5. Any mention of 41 or 4.1 is replaced with 45 or 4.5. Also, if the CMake option LIBOMP_OMP_VERSION is 41, CMake warns that 41 is deprecated and to use 45 instead. llvm-svn: 272687
* kmp_lock.h: Fix VS2013 build after r271324Hans Wennborg2016-06-091-0/+16
| | | | | | | | | | | MSVC doesn't allow std::atomic<>s in a union since they don't have trivial copy constructor. Replacing them with e.g. std::atomic_int works, but that breaks the GCC build on Linux, because then calls to e.g. std::atomic_load_explicit fail, as they expect a real std::atomic<> pointer. Fixing this with an #ifdef to unbreak the build for now. llvm-svn: 272271
* Use C++11 atomics for ticket locks implementationPaul Osmialowski2016-05-311-8/+25
| | | | | | | | | | | | | | | | | | | | | | This patch replaces use of compiler builtin atomics with C++11 atomics for ticket locks implementation. Ticket locks are used in critical places of the runtime, e.g. in the tasking mechanism. The main reason this change was introduced is the problem with work stealing function on ARM architecture which suffered from nasty race condition. It turned out that the root cause of the problem lies in the way ticket locks are implemented. Changing compiler builtins into C++11 atomics solves the problem. Two assertions were added into kmp_tasking.c which are useful for detecting early symptoms of something wrong going on with work stealing, which were among the possible outcomes of the race condition. Differential Revision: http://reviews.llvm.org/D19878 llvm-svn: 271324
* Remove trailing whitespace in src/ directoryJonathan Peyton2016-05-201-1/+1
| | | | | | This patch doesn't affect D19878's context. So D19878 still cleanly applies. llvm-svn: 270252
* Exponential back off logic for test-and-set lockJonathan Peyton2016-04-141-0/+13
| | | | | | | | | | | | | | | | | | | | | | | | | This change adds back off logic in the test and set lock for better contended lock performance. It uses a simple truncated binary exponential back off function. The default back off parameters are tuned for x86. The main back off logic has a two loop structure where each is controlled by a user-level parameter: max_backoff - limits the outer loop number of iterations. This parameter should be a power of 2. min_ticks - the inner spin wait loop number of "ticks" which is system dependent and should be tuned for your system if you so choose. The "ticks" on x86 correspond to the time stamp counter, but on other architectures ticks is a timestamp derived from gettimeofday(). The user can modify these via the environment variable: KMP_SPIN_BACKOFF_PARAMS=max_backoff[,min_ticks] Currently, since the default user lock is a queuing lock, one would have to also specify KMP_LOCK_KIND=tas to use the test-and-set locks. Differential Revision: http://reviews.llvm.org/D19020 llvm-svn: 266329
* Hinted lock (OpenMP 4.5 feature) Updates/Fixes Part 3Jonathan Peyton2015-12-111-4/+33
| | | | | | | | | | | | | | | | | | | | | | | | This change set includes all changes to make the code conform to the OMP 4.5 specification: * Removed hint / hinted_init definitions from include/40 files * Hint values are powers of 2 to enable composition (4.5 spec) * Hinted lock initialization functions were renamed (4.5 spec) kmp_init_lock_hinted -> omp_init_lock_with_hint kmp_init_nest_lock_hinted -> omp_init_nest_lock_with_hint * __kmpc_critical_section_with_hint was added to support a critical section with a hint (4.5 spec) * __kmp_map_hint_to_lock was added to convert a hint (possibly a composite) to an internal lock type * kmpc_init_lock_with_hint and kmpc_init_nest_lock_with_hint were added as internal entries for the hinted lock initializers. The preivous internal functions (__kmp_init*) were moved to kmp_csupport.c and reused in multiple places * Added the two init functions to dllexports * KMP_USE_DYNAMIC_LOCK is turned on if OMP_41_ENABLED is turned on Differential Revision: http://reviews.llvm.org/D15205 llvm-svn: 255376
* Hinted lock (OpenMP 4.5 feature) Updates/Fixes Part 2Jonathan Peyton2015-12-111-50/+48
| | | | | | | | | | | | | | | | | | | * Added a new user TSX lock implementation, RTM, This implementation is a light-weight version of the adaptive lock implementation, omitting the back-off logic for deciding when to specualte (or not). The fall-back lock is still the queuing lock. * Changed indirect lock table management. The data for indirect lock management was encapsulated in the "kmp_indirect_lock_table_t" type. Also, the lock table dimension was changed to 2D (was linear), and each entry is a kmp_indirect_lock_t object now (was a pointer to an object). * Some clean up in the critical section code * Removed the limits of the tuning parameters read from KMP_ADAPTIVE_LOCK_PROPS * KMP_USE_DYNAMIC_LOCK=1 also turns on these two switches: KMP_USE_TSX, KMP_USE_ADAPTIVE_LOCKS Differential Revision: http://reviews.llvm.org/D15204 llvm-svn: 255375
* Hinted lock (OpenMP 4.5 feature) Updates/FixesJonathan Peyton2015-12-111-41/+42
| | | | | | | | | | | | | There are going to be two more patches which bring this feature up to date and in line with OpenMP 4.5. * Renamed jump tables for the lock functions (and some clean up). * Renamed some macros to be in KMP_ namespace. * Return type of unset functions changed from void to int. * Enabled use of _xebgin() et al. intrinsics for accessing TSX instructions. Differential Revision: http://reviews.llvm.org/D15199 llvm-svn: 255373
* Replace DYNA_* names with KMP_* namesJonathan Peyton2015-12-031-47/+47
| | | | llvm-svn: 254637
* [OMPT] Add OMPT events for API lockingJonathan Peyton2015-10-161-24/+27
| | | | | | | | | | | | | | | | | | | | | This fix implements the following OMPT events for the API locking routines: * ompt_event_acquired_lock * ompt_event_acquired_nest_lock_first * ompt_event_acquired_nest_lock_next * ompt_event_init_lock * ompt_event_init_nest_lock * ompt_event_destroy_lock * ompt_event_destroy_nest_lock For the acquired events the depths of the locks ist required, so a return value was added similiar to the return values we already have for the release lock routines. Patch by Tim Cramer Differential Revision: http://reviews.llvm.org/D13689 llvm-svn: 250526
* This is a preparation patch to get information about the actual release ↵Andrey Churbanov2015-04-291-15/+18
| | | | | | status from nested locks for OMPT. llvm-svn: 236114
* Added new user-guided lock api, currently disabled. Use ↵Andrey Churbanov2015-02-201-0/+213
| | | | | | KMP_USE_DYNAMIC_LOCK=1 to enable it. llvm-svn: 230030
* Comments only: removing the Revision and Date svn variables from the top of ↵Andrey Churbanov2015-01-271-2/+0
| | | | | | all the source files. llvm-svn: 227207
* aarch64 port sent by C. BergstromAndrey Churbanov2015-01-131-6/+6
| | | | llvm-svn: 225792
* I apologise in advance for the size of this check-in. At Intel we doJim Cownie2014-10-071-11/+50
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | understand that this is not friendly, and are working to change our internal code-development to make it easier to make development features available more frequently and in finer (more functional) chunks. Unfortunately we haven't got that in place yet, and unpicking this into multiple separate check-ins would be non-trivial, so please bear with me on this one. We should be better in the future. Apologies over, what do we have here? GGC 4.9 compatibility -------------------- * We have implemented the new entrypoints used by code compiled by GCC 4.9 to implement the same functionality in gcc 4.8. Therefore code compiled with gcc 4.9 that used to work will continue to do so. However, there are some other new entrypoints (associated with task cancellation) which are not implemented. Therefore user code compiled by gcc 4.9 that uses these new features will not link against the LLVM runtime. (It remains unclear how to handle those entrypoints, since the GCC interface has potentially unpleasant performance implications for join barriers even when cancellation is not used) --- new parallel entry points --- new entry points that aren't OpenMP 4.0 related These are implemented fully :- GOMP_parallel_loop_dynamic() GOMP_parallel_loop_guided() GOMP_parallel_loop_runtime() GOMP_parallel_loop_static() GOMP_parallel_sections() GOMP_parallel() --- cancellation entry points --- Currently, these only give a runtime error if OMP_CANCELLATION is true because our plain barriers don't check for cancellation while waiting GOMP_barrier_cancel() GOMP_cancel() GOMP_cancellation_point() GOMP_loop_end_cancel() GOMP_sections_end_cancel() --- taskgroup entry points --- These are implemented fully. GOMP_taskgroup_start() GOMP_taskgroup_end() --- target entry points --- These are empty (as they are in libgomp) GOMP_target() GOMP_target_data() GOMP_target_end_data() GOMP_target_update() GOMP_teams() Improvements in Barriers and Fork/Join -------------------------------------- * Barrier and fork/join code is now in its own file (which makes it easier to understand and modify). * Wait/release code is now templated and in its own file; suspend/resume code is also templated * There's a new, hierarchical, barrier, which exploits the cache-hierarchy of the Intel(r) Xeon Phi(tm) coprocessor to improve fork/join and barrier performance. ***BEWARE*** the new source files have *not* been added to the legacy Cmake build system. If you want to use that fixes wil be required. Statistics Collection Code -------------------------- * New code has been added to collect application statistics (if this is enabled at library compile time; by default it is not). The statistics code itself is generally useful, the lightweight timing code uses the X86 rdtsc instruction, so will require changes for other architectures. The intent of this code is not for users to tune their codes but rather 1) For timing code-paths inside the runtime 2) For gathering general properties of OpenMP codes to focus attention on which OpenMP features are most used. Nested Hot Teams ---------------- * The runtime now maintains more state to reduce the overhead of creating and destroying inner parallel teams. This improves the performance of code that repeatedly uses nested parallelism with the same resource allocation. Set the new KMP_HOT_TEAMS_MAX_LEVEL envirable to a depth to enable this (and, of course, OMP_NESTED=true to enable nested parallelism at all). Improved Intel(r) VTune(Tm) Amplifier support --------------------------------------------- * The runtime provides additional information to Vtune via the itt_notify interface to allow it to display better OpenMP specific analyses of load-imbalance. Support for OpenMP Composite Statements --------------------------------------- * Implement new entrypoints required by some of the OpenMP 4.1 composite statements. Improved ifdefs --------------- * More separation of concepts ("Does this platform do X?") from platforms ("Are we compiling for platform Y?"), which should simplify future porting. ScaleMP* contribution --------------------- Stack padding to improve the performance in their environment where cross-node coherency is managed at the page level. Redesign of wait and release code --------------------------------- The code is simplified and performance improved. Bug Fixes --------- *Fixes for Windows multiple processor groups. *Fix Fortran module build on Linux: offload attribute added. *Fix entry names for distribute-parallel-loop construct to be consistent with the compiler codegen. *Fix an inconsistent error message for KMP_PLACE_THREADS environment variable. llvm-svn: 219214
* Commit PowerPC64 support from Carlo Bertolli at IBM.Jim Cownie2014-08-071-1/+1
| | | | llvm-svn: 215093
* Fix typosAlp Toker2014-02-241-1/+1
| | | | llvm-svn: 202018
* For your Christmas hacking pleasure.Jim Cownie2013-12-231-36/+36
| | | | | | | | | | | | | | | | | This release use aligns with Intel(r) Composer XE 2013 SP1 Product Update 2 New features * The library can now be built with clang (though wiht some limitations since clang does not support 128 bit floats) * Support for Vtune analysis of load imbalance * Code contribution from Steven Noonan to build the runtime for ARM* architecture processors * First implementation of runtime API for OpenMP cancellation Bug Fixes * Fixed hang on Windows (only) when using KMP_BLOCKTIME=0 llvm-svn: 197914
* First attempt to import OpenMP runtimeJim Cownie2013-09-271-0/+989
llvm-svn: 191506
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