harmony-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Nathan Beyer" <nbe...@gmail.com>
Subject Re: [drlvm] thread local storage in open/hythread.h
Date Mon, 31 Mar 2008 01:28:36 GMT
On Sun, Mar 30, 2008 at 4:41 PM, Gregory Shimansky
<gshimansky@apache.org> wrote:
>
> On 29 марта 2008 Nathan Beyer wrote:
>  > In open/hythread.h there is the following bit of code.
>  >
>  > #ifdef PLATFORM_POSIX
>  > extern __thread hythread_t tm_self_tls;
>  > #else
>  > extern __declspec(thread) hythread_t tm_self_tls;
>  > #endif //PLATFORM_POSIX
>  >
>  >
>  > hy_inline hythread_t VMCALL hythread_self() {
>  >     return tm_self_tls;
>  > }
>  >
>  > From what I know at the moment, the use of '__thread' isn't a POSIX
>  > standard, but rather a gcc extension and '__declspec(thread)' is a
>  > MSVC thing, so the check isn't quite correct. Neither of these works
>  > on MacOS X and from what I've been able to gather, it shouldn't work
>  > on FreeBSD, but I can't confirm that. In any case, I was looking at
>  > implementing this for MacOSX and FreeBSD using pthread_key_t. It seems
>  > like that could be used for other (all?) platforms as well. Any
>  > thoughts on that?
>
>  AFAIK there are plenty of different implementation for getting TLS in DRLVM's
>  implementation of hythread. There are fast ways like those you've mentioned,
>  slow ways using APR and pthread and very fast ways using inline assembly.
>
>  All of them are quite messed up right now and need some cleaning. The mess is
>  with different defines that rule the whole stuff - it is not always clear
>  which define set is used for a particular implementation on a given platform.

I would agree that the defines are a bit of a mess or at least seem
like it at times.

Do you have any suggestions or preferences about a particular TLS
approach? I'm all for fast, but I tend to lean towards a consistent
(single) clean approach, even it it's not the fastest approach.

>
>  --
>  Gregory
>
Mime
View raw message