[Openmp-commits] [PATCH] D51944: openmp: Use glibc wrappers for accessing cpu affinity mask

Jonathan Peyton via Phabricator via Openmp-commits openmp-commits at lists.llvm.org
Tue Sep 11 14:57:27 PDT 2018

jlpeyton added a comment.

To avoid the glibc version issue, can we just switch the `mask_t` from `unsigned char` to `unsigned long`?  This is the actual underlying type for cpuset according to the man page.  This would require different changes, particularly `__kmp_affin_mask_size`.  I think that in z_Linux_util.cpp:`__kmp_determine_affinity_capable()` (where `__kmp_affin_mask_size` is set), you could change `__kmp_affin_mask_size` to be the closest multiple of `sizeof(unsigned long)`, then the `Mask()` constructor would perform `__kmp_allocate(sizeof(unsigned long)*__kmp_affin_mask_size);`.  Most of the mask API stays the same, but in `set|get_system_affinity()`, have the size argument be `sizeof(unsigned long)*__kmp_affin_mask_size` for the system calls.

Does this make sense?

  rOMP OpenMP


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