Sturla Molden, 11.03.2011 12:13:
OpenMP is a specification, not a particular implementation. Implementation for Cython should either be compiler pragmas or a library.I'd like it to be a library, as it should also be usable from Python. I have made some progress on the library route, depending on Cython's closures. nogil makes things feel a bit awkward, though. We could for example imagine code like this: with openmp.ordered(i): <suite> Context managers are forbidden in nogil AFAIK. So we end up with ugly hacks like this: with nogil: if openmp._ordered(i): # always returns 1, but will synchronize <suite> Would it be possible to: - Make context managers that are allowed without the GIL? We don't need to worry about exceptions, but it should be possible to short-circuit from __enter__ to __exit__.
The two special methods are Python methods. There is no way to call them without holding the GIL. If we wanted to enable something like a context manager inside of a nogil block, it would necessarily be a different protocol.
- Have cpdefs that are callable without the GIL?
"cpdef" functions are meant to be overridable from Python code, so, no, you cannot call them from within a nogil block as they may actually have been overridden.
What's your use actual case for this? Stefan _______________________________________________ cython-devel mailing list cython-devel@python.org http://mail.python.org/mailman/listinfo/cython-devel
