Subject: Re: alternate rough SA patch (works on SMP)
To: Christian Limpach <>
From: Stephan Uphoff <>
List: tech-kern
Date: 06/27/2003 15:28:02
Christian Limpach wrote:
> I've also come up with a patch for pthread/SMP. 
> ....
> Is this going in the right direction?

Hi Christian,

I finally had some time to look at your patch.
Here are a few comments:

- With your patch a LWP that had been blocked (block upcall received by
   libpthread) can return later to user space without the associated
   unblock upcall or holding the virtual processor.
   This will confuse libpthread.
- ltsleep and therefore also copyout can not be called with SCHED_LOCK held.

- as a target for mi_switch the lwp has to be in memory (l_flag & L_INMEM)