On Wed, 2016-04-13 at 17:17 +0800, lh_mouse wrote: > Hi all, > > The 'win32' thread model of gcc has been there since long long ago, being > compatible with very old Windows versions, also having a number of drawbacks: > 0) its implementation is very inefficient, and > 1) its mutexes and condition variables require dynamic initialization and > are unusable in C++11 as std::mutex requires a `constexpr` constructor, and > 2) allocating a number of rarely used mutexes or condition variables would > eventually make the system run out of kernel objects. > > As a solution for 1) and 2), Microsoft introduced keyed events, details of > which can be found here: > http://joeduffyblog.com/2006/11/28/windows-keyed-events-critical-sections-and-new-vista-synchronization-features/
Have you looked at WaitOnAddress and WakeByAddressSingle / WakeByAddressAll too? AFAIK this is new in Windows 8, and seems similar to futexes. I think it might be better to get a std::synchronic (or similar) implementation into GCC, and then use these to implement at least the mutexes: https://github.com/ogiroux/synchronic/blob/master/include/synchronic One benefit would be that we then have one place where we have optimized spinning/blocking in libstdc++ on Windows, and less platform-specific code.