Commit Graph

19 Commits

Author SHA1 Message Date
Terry Wilmarth d8e4cb9121 [OpenMP] libomp: Add new experimental barrier: two-level distributed barrier
Two-level distributed barrier is a new experimental barrier designed
for Intel hardware that has better performance in some cases than the
default hyper barrier.

This barrier is designed to handle fine granularity parallelism where
barriers are used frequently with little compute and memory access
between barriers. There is no need to use it for codes with few
barriers and large granularity compute, or memory intensive
applications, as little difference will be seen between this barrier
and the default hyper barrier. This barrier is designed to work
optimally with a fixed number of threads, and has a significant setup
time, so should NOT be used in situations where the number of threads
in a team is varied frequently.

The two-level distributed barrier is off by default -- hyper barrier
is used by default. To use this barrier, you must set all barrier
patterns to use this type, because it will not work with other barrier
patterns. Thus, to turn it on, the following settings are required:

KMP_FORKJOIN_BARRIER_PATTERN=dist,dist
KMP_PLAIN_BARRIER_PATTERN=dist,dist
KMP_REDUCTION_BARRIER_PATTERN=dist,dist

Branching factors (set with KMP_FORKJOIN_BARRIER, KMP_PLAIN_BARRIER,
and KMP_REDUCTION_BARRIER) are ignored by the two-level distributed
barrier.

Patch fixed for ITTNotify disabled builds and non-x86 builds

Co-authored-by: Jonathan Peyton <jonathan.l.peyton@intel.com>
Co-authored-by: Vladislav Vinogradov <vlad.vinogradov@intel.com>

Differential Revision: https://reviews.llvm.org/D103121
2021-07-29 14:09:26 -05:00
Johannes Doerfert 4eb90e893f Revert "[OpenMP] Add Two-level Distributed Barrier"
This reverts commit 25073a4ecf.

This breaks non-x86 OpenMP builds for a while now. Until a solution is
ready to be upstreamed we revert the feature and unblock those builds.
See:
  https://reviews.llvm.org/rG25073a4ecfc9b2e3cb76776185e63bfdb094cd98#1005821
and
  https://reviews.llvm.org/rG25073a4ecfc9b2e3cb76776185e63bfdb094cd98#1005821

The currently proposed fix (D104788) seems not to be ready yet:
  https://reviews.llvm.org/D104788#2841928
2021-06-29 09:38:27 -05:00
Terry Wilmarth 25073a4ecf [OpenMP] Add Two-level Distributed Barrier
Two-level distributed barrier is a new experimental barrier designed
for Intel hardware that has better performance in some cases than the
default hyper barrier.

This barrier is designed to handle fine granularity parallelism where
barriers are used frequently with little compute and memory access
between barriers.  There is no need to use it for codes with few
barriers and large granularity compute, or memory intensive
applications, as little difference will be seen between this barrier
and the default hyper barrier. This barrier is designed to work
optimally with a fixed number of threads, and has a significant setup
time, so should NOT be used in situations where the number of threads
in a team is varied frequently.

The two-level distributed barrier is off by default -- hyper barrier
is used by default. To use this barrier, you must set all barrier
patterns to use this type, because it will not work with other barrier
patterns.  Thus, to turn it on, the following settings are required:

KMP_FORKJOIN_BARRIER_PATTERN=dist,dist
KMP_PLAIN_BARRIER_PATTERN=dist,dist
KMP_REDUCTION_BARRIER_PATTERN=dist,dist

Branching factors (set with KMP_FORKJOIN_BARRIER, KMP_PLAIN_BARRIER,
and KMP_REDUCTION_BARRIER) are ignored by the two-level distributed
barrier.

Differential Revision: https://reviews.llvm.org/D103121
2021-06-16 15:34:55 -05:00
Shilei Tian 309b00a42e [OpenMP][NFC] clang-format the whole openmp project
Same script as D95318. Test files are excluded.

Reviewed By: AndreyChurbanov

Differential Revision: https://reviews.llvm.org/D97088
2021-02-20 12:46:32 -05:00
Terry Wilmarth 6b316febb4 [OpenMP] libomp: Handle implicit conversion warnings
This patch partially prepares the runtime source code to be built with
-Wconversion, which should trigger warnings if any implicit conversions
can possibly change a value. For builds done with icc or gcc, all such
warnings are handled in this patch. clang gives a much longer list of
warnings, particularly for sign conversions, which the other compilers
don't report. The -Wconversion flag is commented into cmake files, but
I'm not going to turn it on. If someone thinks it is important, and wants
to fix all the clang warnings, they are welcome to.

Types of changes made here involve either improving the consistency of types
used so that no conversion is needed, or else performing careful explicit
conversions, when we're sure a problem won't arise.

Patch is a combination of changes by Terry Wilmarth and Johnny Peyton.

Differential Revision: https://reviews.llvm.org/D92942
2020-12-31 00:39:57 +03:00
AndreyChurbanov fff1abc406 [OpenMP] NFC: comment adjusted 2020-12-07 19:50:14 +03:00
AndreyChurbanov 22558c8501 [OpenMP] libomp: Fix possible NULL dereferences
Check pointer returned by strchr, as it can be NULL in case of broken
format of input string. Introduced new function __kmp_str_loc_numbers
for fast parsing of numbers only in the location string.
Also made some cleanup of __kmp_str_loc_init declaration and usage:
- changed type of init_fname parameter to bool;
- changed input from true to false in places where fname is not used.

Differential Revision: https://reviews.llvm.org/D90962
2020-12-07 19:09:07 +03:00
Kelvin Li ed5fe64581 [OpenMP] NFC: Fix trivial typos in comments
Submitted by: kiszk

Differential Revision: https://reviews.llvm.org/D72171
2020-01-03 22:03:42 -05:00
Chandler Carruth 57b08b0944 Update more file headers across all of the LLVM projects in the monorepo
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
2019-01-19 10:56:40 +00:00
Jonathan Peyton 6d88e049dc [OpenMP] Implement OpenMP 5.0 affinity format functionality
This patch adds the affinity format functionality introduced in OpenMP 5.0.
This patch adds: Two new environment variables:

OMP_DISPLAY_AFFINITY=TRUE|FALSE
OMP_AFFINITY_FORMAT=<string>
and Four new API:
1) omp_set_affinity_format()
2) omp_get_affinity_format()
3) omp_display_affinity()
4) omp_capture_affinity()
The affinity format functionality has two ICV's associated with it:
affinity-display-var (bool) and affinity-format-var (string).
The affinity-display-var enables/disables the functionality through the
envirable OMP_DISPLAY_AFFINITY. The affinity-format-var is a formatted
string with the special field types beginning with a '%' character
similar to printf
For example, the affinity-format-var could be:
"OMP: host:%H pid:%P OStid:%i num_threads:%N thread_num:%n affinity:{%A}"

The affinity-format-var is displayed by every thread implicitly at the beginning
of a parallel region when any thread's affinity has changed (including a brand
new thread being spawned), or explicitly using the omp_display_affinity() API.
The omp_capture_affinity() function can capture the affinity-format-var in a
char buffer. And omp_set|get_affinity_format() allow the user to set|get the
affinity-format-var explicitly at runtime. omp_capture_affinity() and
omp_get_affinity_format() both return the number of characters needed to hold
the entire string it tried to make (not including NULL character). If not
enough buffer space is available,
both these functions truncate their output.

Differential Revision: https://reviews.llvm.org/D55148

llvm-svn: 349089
2018-12-13 23:14:24 +00:00
Jonathan Peyton 60eec6fecb [OpenMP][OMPT] A few improvements
This change includes miscellaneous improvements as follows:
1) Added ompt_get_proc_id() implementation for Windows
2) Added parser and print tool for omp-tool-var, just in case it needs
   to be printed (OMP_DISPLAY_ENV)
3) omp_control_tool is exported on Windows

Patch by Hansang Bae

Differential Revision: https://reviews.llvm.org/D50538

llvm-svn: 343137
2018-09-26 20:19:44 +00:00
Jonas Hahnfeld aeb40adabf Remove const from variables with dynamic memory
Allocated memory is typically not 'const' if it needs to be freed.
This patch removes around 50 wrong const attributes, modifies the
corresponding functions and finally gets rid of some const_casts.
These have especially been strange for __kmp_str_fname_free() that
added a 'const' to call __kmp_str_free() which removed it again.

Two minor cleanups that I performed in this process:
 * __kmp_tool_libraries now lives in kmp_settings.cpp as it is
   used nowhere else.
 * __kmp_msg_empty was removed as it was never used and Clang
   now complained that it was assigned a string literal that
   is 'const char *'.

Differential Revision: https://reviews.llvm.org/D39755

llvm-svn: 317797
2017-11-09 15:52:25 +00:00
Jonathan Peyton 94a114fc39 Apply formatting changes
.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
2017-10-20 19:30:57 +00:00
Jonathan Peyton bd3a7633f1 Remove unnecessary semicolons
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
2017-09-27 20:36:27 +00:00
Jonathan Peyton 0447708f8d Use va_copy instead of __va_copy to fix building libomp against musl libc
Fixes https://bugs.llvm.org/show_bug.cgi?id=34040

Patch by Peter Levine

Differential Revision: https://reviews.llvm.org/D36343

llvm-svn: 311269
2017-08-19 23:53:36 +00:00
Andrey Churbanov c47afcd9bb OpenMP RTL cleanup: eliminated warnings with -Wcast-qual.
Changes are: replaced C-style casts with cons_cast and reinterpret_cast;
type of several counters changed to signed; type of parameters of 32-bit and
64-bit AND and OR intrinsics changes to unsigned; changed files formatted
using clang-format version 3.8.1.

Differential Revision: https://reviews.llvm.org/D34759

llvm-svn: 307020
2017-07-03 11:24:08 +00:00
Jonathan Peyton 3041982dd1 Clang-format and whitespace cleanup of source code
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
2017-05-12 18:01:32 +00:00
Jonathan Peyton de4749b748 Follow up to r289732: Update comments in source files to reference .cpp files
Patch by Hansang Bae

llvm-svn: 289739
2016-12-14 23:01:24 +00:00
Jonathan Peyton 7cc577a4ef Change source files from .c to .cpp
Patch by Hansang Bae

Differential Revision: https://reviews.llvm.org/D26688

llvm-svn: 289732
2016-12-14 22:39:11 +00:00