Summary:
Implemented by Dejan Latinovic
See https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=790735 for more more information

Reviewers: AndreyChurbanov, jlpeyton

Subscribers: openmp-commits, mgorny

Differential Revision: https://reviews.llvm.org/D26576

llvm-svn: 289032

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

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

These changes allow libhwloc to be used as the topology discovery/affinity
mechanism for libomp.  It is supported on Unices. The code additions:
* Canonicalize KMP_CPU_* interface macros so bitmask operations are
  implementation independent and work with both hwloc bitmaps and libomp
  bitmaps.  So there are new KMP_CPU_ALLOC_* and KMP_CPU_ITERATE() macros and
  the like. These are all in kmp.h and appropriately placed.
* Hwloc topology discovery code in kmp_affinity.cpp. This uses the hwloc
  interface to create a libomp address2os object which the rest of libomp knows
  how to handle already.
* To build, use -DLIBOMP_USE_HWLOC=on and
  -DLIBOMP_HWLOC_INSTALL_DIR=/path/to/install/dir [default /usr/local]. If CMake
  can't find the library or hwloc.h, then it will tell you and exit.

Differential Revision: http://reviews.llvm.org/D13991

llvm-svn: 254320

These changes include:
 1) Machine hierarchy now uses the base_num_threads field to indicate the 
    maximum number of threads the current hierarchy can handle without a resize.
 2) In __kmp_get_hierarchy, we need to get depth after any potential resize
    is done.
 3) Cleanup of hierarchy resize code to support 1 above.

Differential Revision: http://reviews.llvm.org/D14455

llvm-svn: 252475

This is a follow up to the hierarchy cleanup patch.
Added some clarifying comments to hierarchy_info.
Fixed a bug with the depth field not being updated cleanly during a resize.
Fixed resize to first check capacity as determined by maxLevels before actually doing the full resize.

Differential Revision: http://reviews.llvm.org/D12562

llvm-svn: 247333

Some of this is improvement to code suggested by Hal Finkel. Four changes here:
1.Cleanup of hierarchy code to handle all hierarchy cases whether affinity is available or not
2.Separated this and other classes and common functions out to a header file
3.Added a destructor-like fini function for the hierarchy (and call in __kmp_cleanup)
4.Remove some redundant code that is hopefully no longer needed

Differential Revision: http://reviews.llvm.org/D12449

llvm-svn: 247326