hwloc documentation guarantees the only object that is always present
in the topology is PU. We can check the presence of other objects
in the topology, just in case.
Differential Revision: https://reviews.llvm.org/D84065
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
Made type of depth of hwloc object to correapond with
change from unsigned in hwloc 1,x to int in hwloc 2.x.
This eliminates the warning on signed-unsigned comparison.
Differential Revision: https://reviews.llvm.org/D62332
llvm-svn: 362401
Currently cores within package that share the same L2 cache are grouped together.
The current logic behind this assumes that the L2 cache is always at deeper
(or the same) level than the package itself. In case when L2 cache is common
for all packages (and the packages are at deeper level than L2 cache) the whole of
the further topology discovery fails to find any computational units resulting in
following assertion:
Assertion failure at kmp_affinity.cpp(715): nActiveThreads == __kmp_avail_proc.
OMP: Error #13: Assertion failure at kmp_affinity.cpp(715).
This patch adds a bit of a logic that prevents such situation from occurring.
Differential Revision: https://reviews.llvm.org/D61796
llvm-svn: 360890
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
The compiler warns about an unused variable/statement:
runtime/src/kmp_affinity.cpp:4958:18: warning: statement has no effect [-Wunused-value]
KA_TRACE(1000, ; {
^
runtime/src/kmp_debug.h:84:24: note: in definition of macro 'KA_TRACE'
__kmp_debug_printf x; \
^
Instead of the unused reference to this function, this patch now calls the function
with an empty string. The call to this function should have no effect.
Patch provided by joachim.protze
Reviewers: jlpeyton, hbae, AndreyChurbanov
Reviewed By: AndreyChurbanov
Tags: #openmp, #ompt
Differential Revision: https://reviews.llvm.org/D56775
llvm-svn: 351323
Using proc_bind clause on a nested #pragma omp parallel region
with KMP_AFFINITY set causes an assertion error. This assertion occurs because
the place-partition-var is not properly initialized in the nested master threads.
Trying to get an intuitive result with KMP_AFFINITY + proc_bind is difficult
because of how the KMP_AFFINITY gtid-to-place mapping occurs. This
patch creates an initial place list no matter what affinity mechanism is used.
For KMP_AFFINITY, the place-partition-var is initialized to all the places.
Differential Revision: https://reviews.llvm.org/D55795
llvm-svn: 351227
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
Balanced affinity only updated the thread's affinity with the operating system.
This change also has the thread's private mask reflect that change as well so
that any API that probes the thread's affinity mask will report the correct
mask value.
Differential Revision: https://reviews.llvm.org/D52379
llvm-svn: 343142
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
This patch introduces the logic implementing hierarchical scheduling.
First and foremost, hierarchical scheduling is off by default
To enable, use -DLIBOMP_USE_HIER_SCHED=On during CMake's configure stage.
This work is based off if the IWOMP paper:
"Workstealing and Nested Parallelism in SMP Systems"
Hierarchical scheduling is the layering of OpenMP schedules for different layers
of the memory hierarchy. One can have multiple layers between the threads and
the global iterations space. The threads will go up the hierarchy to grab
iterations, using possibly a different schedule & chunk for each layer.
[ Global iteration space (0-999) ]
(use static)
[ L1 | L1 | L1 | L1 ]
(use dynamic,1)
[ T0 T1 | T2 T3 | T4 T5 | T6 T7 ]
In the example shown above, there are 8 threads and 4 L1 caches begin targeted.
If the topology indicates that there are two threads per core, then two
consecutive threads will share the data of one L1 cache unit. This example
would have the iteration space (0-999) split statically across the four L1
caches (so the first L1 would get (0-249), the second would get (250-499), etc).
Then the threads will use a dynamic,1 schedule to grab iterations from the L1
cache units. There are currently four supported layers: L1, L2, L3, NUMA
OMP_SCHEDULE can now read a hierarchical schedule with this syntax:
OMP_SCHEDULE='EXPERIMENTAL LAYER,SCHED[,CHUNK][:LAYER,SCHED[,CHUNK]...]:SCHED,CHUNK
And OMP_SCHEDULE can still read the normal SCHED,CHUNK syntax from before
I've kept most of the hierarchical scheduling logic inside kmp_dispatch_hier.h
to try to keep it separate from the rest of the code.
Differential Revision: https://reviews.llvm.org/D47962
llvm-svn: 336571
Currently, the affinity API reports garbage for the initial place list and any
thread's place lists when using KMP_AFFINITY=none|compact|scatter.
This patch does two things:
for KMP_AFFINITY=none, Creates a one entry table for the places, this way, the
initial place list is just a single place with all the proc ids in it. We also
set the initial place of any thread to 0 instead of KMP_PLACE_ALL so that the
thread reports that single place (place 0) instead of garbage (-1) when using
the affinity API.
When non-OMP_PROC_BIND affinity is used
(including KMP_AFFINITY=compact|scatter), a thread's place list is populated
correctly. We assume that each thread is assigned to a single place. This is
implemented in two of the affinity API functions
Differential Revision: https://reviews.llvm.org/D45527
llvm-svn: 330283
There are two /proc/cpuinfo layots in use for AArch64: old and new.
The old one has all 'processor : n' lines in one section, hence
checking for duplications does not make sense.
Differential Revision: https://reviews.llvm.org/D41000
llvm-svn: 320593
To make thread affinity work according to the OpenMP spec, the
runtime needs information about the hardware topology. On Linux
the default way is to parse /proc/cpuinfo which contains this
information for x86 machines but (at least) not for AArch64 and
Power architectures.
Fortunately, there is a different code path which is able to get
that data from sysfs. The needed patch has landed in 2006 for
Linux 2.6.16 which is safe to assume nowadays (even RHEL 5 had
a kernel version derived from 2.6.18, and we are now at RHEL 7!).
Differential Revision: https://reviews.llvm.org/D40357
llvm-svn: 320151
Redundant extra verbose output of binding to full mask in case
affinity=balanced or OMP_PLACES=<any> or OMP_PROC_BIND=<any>
Differential Revision: https://reviews.llvm.org/D40624
llvm-svn: 319960
Added two warnings:
1) Before building the topology map check if tiles are requested but the
topo method is not hwloc;
2) After building the topology map check if tiles are requested but not
detected by the library.
Patch by Olga Malysheva
Differential Revision: https://reviews.llvm.org/D40340
llvm-svn: 319374
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
Changes are: got all atomics to accept volatile pointers that allowed
to simplify many type conversions. Windows specific code fixed correspondingly.
Differential Revision: https://reviews.llvm.org/D35417
llvm-svn: 308164
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
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
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
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
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
Clang 4.0 trunk warns:
warning: logical not is only applied to the left hand side of this bitwise operator [-Wlogical-not-parentheses]
This points to a potential bug if the code really wants to check if the single
bit is not set: If for example (buf.edx >> 9) = 2 (has any bit set except the
least significant one), 'logical not' will return 0 which stays 0 after the
'bitwise and'.
To do this correctly we first need to evaluate the 'bitwise and'. In that case
it returns 2 & 1 = 0 which after the 'logical not' evaluates to 1.
Differential Revision: https://reviews.llvm.org/D28599
llvm-svn: 291764
This set of changes enables the affinity interface (Either the preexisting
native operating system or HWLOC) to be dynamically set at runtime
initialization. The point of this change is that we were seeing performance
degradations when using HWLOC. This allows the user to use the old affinity
mechanisms which on large machines (>64 cores) makes a large difference in
initialization time.
These changes mostly move affinity code under a small class hierarchy:
KMPAffinity
class Mask {}
KMPNativeAffinity : public KMPAffinity
class Mask : public KMPAffinity::Mask
KMPHwlocAffinity
class Mask : public KMPAffinity::Mask
Since all interface functions (for both affinity and the mask implementation)
are virtual, the implementation can be chosen at runtime initialization.
Differential Revision: https://reviews.llvm.org/D26356
llvm-svn: 286890
Rather than checking KMP_CPU_SETSIZE, which doesn't exist when using Hwloc, we
use the get_max_proc() function which can vary based on the operating system.
For example on Windows with multiple processor groups, it might be the case that
the highest bit possible in the bitmask is not equal to the number of hardware
threads on the machine but something higher than that.
Differential Revision: https://reviews.llvm.org/D24206
llvm-svn: 281245
When affinity isn't supported, __kmp_affinity_compact doesn't exist. The
problem is that in kmp_affinity.h there is a function which uses it without the
proper KMP_AFFINITY_SUPPORTED guard around it. The compiler was smart enough to
ignore it and the function __kmp_affinity_cmp_Address_child_num which relies on
it, but I think it is cleaner to have it under the proper guard. Since the
function is only used in the kmp_affinity.cpp file and there aren't any plans to
have it elsewhere. I have moved it there.
llvm-svn: 280542
This patch enables balanced affinity on machines that do not have
hardware threads and have cores clustered into packages. In facts,
balacing algorithm could be generalized for any arrangement with
at least two levels of hierarchy (depth > 1).
Differential Revision: https://reviews.llvm.org/D22365
llvm-svn: 277212
A couple improvements:
1) Add ability to limit fullMask size when KMP_HW_SUBSET limits resources.
2) Make KMP_HW_SUBSET work for affinity_none, and only limit fullMask in this case.
Patch by Andrey Churbanov.
Differential Revision: http://reviews.llvm.org/D21528
llvm-svn: 273278
Change hwloc discovery algorithm to print topology for only accessible
resources, and report uniformity correspondingly, similar to what other topology
discovery algorithms do. Fixes minor inconsistency in total topology reported
and resources used for threads binding in case hwloc used.
Patch by Andrey Churbanov.
Differential Revision: http://reviews.llvm.org/D21389
llvm-svn: 272952
Cleanup: fixed missing memory cleanup in couple of corner cases. Fixes possible
memory leak in some corner cases
Patch by Andrey Churbanov
Differential Revision: http://reviews.llvm.org/D21355
llvm-svn: 272946
Deprecate KMP_PLACE_THREADS and rename it to KMP_HW_SUBSET due to confusion
about its purpose and function among users. KMP_HW_SUBSET is an environment
variable which allows users to easily pick a subset of the hardware topology to
use. e.g., KMP_HW_SUBSET=30c,2t means use 30 cores, 2 threads per core.
Patch by Andrey Churbanov
Differential Revision: http://reviews.llvm.org/D21340
llvm-svn: 272937