Re: port threadsafety redux

[Ludovic Courtès]

Andy Wingo <address@hidden> skribis:

> Namely, ports can have associated recursive mutexes.  They can be in a
> mode in which every operation on a port grabs the mutex.  The interface
> to set a port into unlocked mode (à la fsetlocking) is unimplemented,
> but the machinery is there.
>
> This change fixed the crashes I was seeing, but it slows down port
> operations.  For an intel chip from a couple years ago the slowdown was
> something on the order of 3x, for a tight putchar() loop; for Loongson
> it could be as bad as 26x.  Mark was unhappy with this.

Thanks for bringing up the issue.  I’d like to hear what Mark thinks.
:-)

Ludo’.