David, any new thoughts?
Thanks /R On Apr 12, 2013, at 8:06 AM, Rickard Bäckman wrote: > > On Apr 12, 2013, at 7:34 AM, David Holmes wrote: > >> On 12/04/2013 3:01 PM, Rickard Bäckman wrote: >>> >>> On Apr 12, 2013, at 1:04 AM, David Holmes wrote: >>> >>>> On 11/04/2013 11:02 PM, Rickard Bäckman wrote: >>>>> On Apr 11, 2013, at 2:39 PM, David Holmes wrote: >>>>>> So what did you mean about pthread_semaphore (what is that anyway?) ?? >>>>> >>>>> Never mind, pthread condition variables. >>>> >>>> Ah I see. >>>> >>>>>> >>>>>> I really, really, really don't like seeing three versions of this class >>>>>> :( Can't BSD and Linux at least share a POSIX version? (And I wonder if >>>>>> we can actually mix-n-match UI threads on Solaris with POSIX semaphores >>>>>> on Solaris?) >>>>> >>>>> I don't like it either, our OS code isn't really helpful when it comes do >>>>> reusing things :) Not sure how I would layout things to make them only >>>>> available on BSD (Not Mac) and Linux. I guess os_posix.hpp with lots of >>>>> #ifdefs, but I'm not sure I"m feeling that happy about that. >>>> >>>> Why would the os_posix version need a lot of ifdefs? >>> >>> Well, I guess we would need: >>> >>> (in ifdef pseudo language) >>> >>> #ifdef (LINUX || (BSD && !APPLE)) >>> … >>> #endif >> >> But if it isn't "posix" then we won't be building os_posix - right? > > Linux, Solaris, Bsd & Mac builds and include os_posix. They are all > "implementing posix" we are just not using the same semaphore implementation > on all of them. > >> >>> The second interesting problem this will get us into is that sem_t is not >>> declared in this context. Where do we put the #include <semaphore.h>? >>> Impossible in os_posix.hpp since it is included in the middle of a class >>> definition. I could put it in os.hpp in the #ifdef path that does the >>> jvm_platform.h includes, not sure if that is very pretty either. >> >> Semaphores are already used by the signal handler thread - semaphore.h is >> included in os_linux.cpp etc, so why would os_posix be any different ? >> >> But couldn't we just have a Semaphore.h/cpp with any needed ifdefs? >> >>>> Do we really have four versions: >>>> - linux (posix) >>>> - BSD (posix) >>>> - Solaris >>>> - Mac (different to BSD?) >>>> >>> >>> 3: >>> 1) linux & bsd uses the sem_ interface >>> 2) solaris uses the sema_ interface >>> 3) mac uses the semaphore_ interface >> >> Okay but if mac is BSD why can't we use bsd ie posix interface instead of >> the mach semaphore_ ? > > Because apple decided not to implement sem_timedwait. > On Solaris we use sema_ because sem_ requires us to link with -lrt which we > currently don't (and I'm not really feeling like adding it) > >> >> >> BTW I like the idea of using the semaphore, we're just haggling on the >> details. ;-) > > I'm fine with that :) > > /R > >> >> Thanks, >> David >> >>> /R >>> >>>> ?? >>>> >>>> David >>>> ----- >>> >
