On Sun, Nov 08, 2015 at 06:35:36AM +0800, Paul Goyette wrote: > On Sat, 7 Nov 2015, Joerg Sonnenberger wrote: > > >On Sat, Nov 07, 2015 at 10:55:49AM +0800, Paul Goyette wrote: > >>I'd like to understand the rationale that makes POSIX sempahores a > >>non-optional component of the kernel, while POSIX message queues are > >>still optional. Both seem to be related specifically to use in the > >>librt real-time library. > > > >Semaphores are used quite a lot and not only required by librt, but > >also by libpthread. I'm not sure what is using message queues. > > Hmmm, sounds like a great reason to include the semaphore code in > every kernel by default. But it doesn't sound sufficiently critical > to _prevent_ it from being removed from custom kernels if explicitly > requested by the user. > > I'd like to suggest that this code once again become an option. Rather > than adding an option to every kernel configuration file, however, we > can simply add it to src/sys/conf/std where it will get included by > default, in the same manner as MQUEUE. (I also propose use of "option > SEMAPHORE" rather than P1003_1B_SEMAPHORE, similar to MQUEUE.)
I don't see the point in having options for every single system call or the like. At best, it is a form of modularity masturbation and at worst, it is asking for difficult to analyze bugs when someone actually insists on removing them. Joerg
