Re: [Qemu-devel] [patch v4 08/16] QemuThread: make QemuThread as tls to store extra info

[Paolo Bonzini]

Il 23/10/2012 13:50, Peter Maydell ha scritto:
> On 23 October 2012 12:48, Paolo Bonzini <address@hidden> wrote:
>> Il 22/10/2012 19:13, Peter Maydell ha scritto:
>>>>> Can't we enhance qemu-tls.h to work via pthread_setspecific in case
>>>>> __thread is not working and use that abstraction (DECLARE/DEFINE_TLS)
>>>>> directly?
>>> Agreed. (There were prototype patches floating around for Win32
>>> at least). The only reason qemu-tls.h has the dummy not-actually-tls
>>> code for non-linux is that IIRC we wanted to get the linux bits
>>> in quickly before a release and we never got round to going back
>>> and doing it properly for the other targets.
>>
>> Which will be "never" for OpenBSD.  It just doesn't have enough support.
>>
>> Thread-wise OpenBSD is 100% crap, and we should stop supporting it IMHO
>> until they finish their "new" thread library that's been in the works
>> for 10 years or so.  FreeBSD is totally ok.
> 
> It doesn't support any kind of TLS? Wow.

It does support pthread_get/setspecific, but it didn't support something
else so the qemu-tls.h variant that used pthread_get/setspecific didn't
work either.

And it doesn't support sigaltstack in threads, so it's the only platform
where the gthread-based coroutines are used.  Those are buggy because
the coroutines tend to get random signal masks.

Paolo