I've found it very difficult to get test/parallel/omp_nested.c to pass
consistently across my build environments. The problem is that it creates N^2
threads (it is testing nested parallel regions), and that often exceeds the
thread limits on systems with many cores. We do raise the process limits in
lit, and that often helps, but if running lit with a smaller number of threads
or on a system where we're otherwise resource constrained, this particular test
tends to fail (because the runtime cannot create a sufficient number of
threads).
This seems to work: if the maximum number of threads is more than some small
number, then cap the number of threads used for the parallel region. The choice
of 4 here is somewhat arbitrary.
Differential Revision: https://reviews.llvm.org/D32033
llvm-svn: 306357
Summary: On BSDs, there is no `libdl.so`, and functions like `dlopen`
are implemented in the main C library instead. Use the `CMAKE_DL_LIBS`
variable instead of hardcoding a dependency on the `dl` library.
Reviewers: grokos, joerg, emaste
Reviewed By: emaste
Subscribers: jlpeyton, mgorny, openmp-commits
Differential Revision: https://reviews.llvm.org/D34632
llvm-svn: 306319
Reset affinity to none (false for proc-bind-var) so that threads in the child
processes are not bound tightly, unless the user explicitly sets this in
KMP_AFFINITY/OMP_PROC_BIND, in child processes. This can improve
performance for scripting languages which fork for parallelism like Python's
multiprocessing module.
Differential Revision: https://reviews.llvm.org/D34154
llvm-svn: 305513
If OpenMP is initialized before fork()-ing occurs and affinity is set to
something like compact, then the master thread will be pinned to a single HW
thread/core after initialization. If the master (or any other thread) then
forks N processes, all N processes will then be pinned to that same single HW
thread/core. To reset the affinity for the new child process, the atfork
handler for the child process can call kmp_set_thread_affinity_mask_initial()
to reset its affinity to the initial affinity of the application before it
re-initializes libomp. The parent process will not be affected and still
keeps its affinity setting.
Differential Revision: https://reviews.llvm.org/D34118
llvm-svn: 305306
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
Some code was restructured to move it under KMP_DEBUG. The rest is
formatting changes to fix some things broken by clang-format
Patch by Terry Wilmarth
Differential Revision: https://reviews.llvm.org/D33744
llvm-svn: 304438
With these settings, the create_hwloc_map() method was being called causing an
assert(). After some consideration, it was determined that disabling affinity
explicitly should just disable hwloc as well. i.e., KMP_AFFINITY overrides
KMP_TOPOLOGY_METHOD. This lets the user know that the Hwloc mechanism is being
ignored when KMP_AFFINITY=disabled.
Differential Revision: https://reviews.llvm.org/D33208
llvm-svn: 304344
This change checks if the initial affinity mask is equal to exactly one
Windows processor group's affinity mask. If it is, then the code does not
respect the initial affinity mask and uses the entire machine instead.
The reasoning behind this is that, by default, Windows assigns exactly one
processor group as the initial affinity mask even when there are multiple
Windows processor groups available. User's typically want to use the whole
machine, so we ignore this special case and use the entire machine.
If the initial affinity mask is a proper subset of one group, or spans multiple
groups, then the initial affinity mask is respected since we can assume that the
operating system did not assign this initial affinity mask. This change only
affects machines with multiple processor groups
Differential Revision: https://reviews.llvm.org/D33210
llvm-svn: 304343
An assert() was being tripped when KMP_AFFINITY=respect + Multiple Processor
Groups. Let __kmp_affinity_create_proc_group_map() function be able to create
address2os object which contains a single group by deleting restriction that
process affinity mask must span multiple groups.
llvm-svn: 303101
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
This patch chagnes the plugin interface so that:
1) future plugins can take advantage of systems with shared CPU/device storage
2) instead of using base addresses, target regions are launched by providing target addresseds and base offsets explicitly.
Differential revision: https://reviews.llvm.org/D33028
llvm-svn: 302663
Older Hwloc libraries (< 1.10.0) don't offer the HWLOC_OBJ_NUMANODE nor
HWLOC_OBJ_PACKAGE types. Instead they are named HWLOC_OBJ_NODE and
HWLOC_OBJ_SOCKET instead. This patch just defines the newer names based on
the older names when using an older Hwloc.
Differential Revision: https://reviews.llvm.org/D32496
llvm-svn: 301349
Without this fix cancellation status for parallel, sections and for persists
across construct boundaries.
Differential Revision: https://reviews.llvm.org/D31419
llvm-svn: 299434
This change slightly improves performance of KMP_YIELD_NOW() macro, by using
_rdtsc() intrinsic function if possible.
Patch by Hansang Bae
Differential Revision: https://reviews.llvm.org/D31008
llvm-svn: 298314
Affinity initialization code expects __kmp_affinity_type has the value
affinity_default by default, but the cleanup code does not properly set the
value back to affinity_default. This may introduce some issues when multiple
roots are trying to initialize/uninitialize the runtime successively.
Patch by Hansang Bae
Differential Revision: https://reviews.llvm.org/D31012
llvm-svn: 298313
This change fixes an assertion failure the in case KMP_AFFINITY is set with
'proclist' specified but without 'explicit'
e.g., KMP_AFFINITY=verbose,proclist=[0-31]
Patch by Olga Malysheva
Differential Revision: https://reviews.llvm.org/D30404
llvm-svn: 297480
Summary:
Bionic didn't get a GNU style strerror_r until Android M. Until then
we unconditionally exposed the POSIX one. Expand the check to account
for this.
Reviewers: pirama, AndreyChurbanov, jlpeyton
Reviewed By: jlpeyton
Subscribers: openmp-commits, srhines
Differential Revision: https://reviews.llvm.org/D30056
llvm-svn: 297235
Add build option LIBOMP_OMP_VERSION=50, 5.0 headers, and add the year/month
associated with OpenMP 5.0 in relevant source locations. Also, remove the
deprecated LIBOMP_OMP_VERSION=41 option.
Patch by Olga Malysheva
Differential Revision: https://reviews.llvm.org/D30450
llvm-svn: 297083
This adds AArch64 support to recently added part of the runtime responsible for offloading to target. This piece of code allows offloading-to-self on AArch64 machines.
Differential Revision: https://reviews.llvm.org/D30644
llvm-svn: 297070
This section of code (__kmp_test_then_* functions) is guarded by
(KMP_ARCH_X86 || KMP_ARCH_X86_64) so it does not make sense to have other
architecture guards inside this section. Non-x86 architectures always
use intrinsics (__sync_*)
llvm-svn: 296525
When using -rtlib=libgcc, the fallback implementation of __atomic_*
builtins is provided via libatomic (included in GCC). However, neither
GCC itself nor clang link libatomic implicitly, and it seems that GCC
upstream expects projects to link it explicitly as necessary.
Since compiler-rt provides __atomic_* builtins directly in the main
library, check if they are provided by the default libraries first.
If they are not, check if -latomic is available to provide them
and add explicit -latomic for tests in this case.
This fixes unresolved __atomic_load() references when running openmp
tests on i386 with libgcc backend.
Differential Revision: https://reviews.llvm.org/D30083
llvm-svn: 296183