[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: deferred cancellation of ipc
From: |
Marcus Brinkmann |
Subject: |
Re: deferred cancellation of ipc |
Date: |
Wed, 15 Oct 2003 01:49:54 +0200 |
User-agent: |
Mutt/1.5.4i |
On Tue, Oct 14, 2003 at 04:00:35PM -0700, Volkmar Uhlig wrote:
> After reading your initial scenario again there is a rather simple
> solution--use zero timeouts. Instead of storing the cancel flag you
> store the intended send timeout value, which could be zero. Of course
> you still run into a race on MP if you don't use some synchronization
> primitive, but that is a different issue you have to deal with anyway.
> This solution assumes that you _only_ want to ensure that the thread
> does not block.
That doesn't seem to give me any relief. If I see the zero timeout in my
thread for the IPC, I can also see a cancel flag and exit right away. I can
do a quick poll on the IPC, if I want to, but as you said, the
synchronization problem has to be solved, because the race happens if the
cancel happens after I checked the cancel flag and before I enter the IPC
call.
> > Or does maybe stopping a thread on another CPU count as
> > preemption and is also delayed?
>
> Sorry, but I don't get what you mean. What is "stopping"; exregs?
Yes. Also called halting. If I stop/halt a thread on another cpu, will
this stop/halt the thread even if it delayed preemption? Or does preemption
delay prevent that?
Thanks,
Marcus
--
`Rhubarb is no Egyptian god.' GNU http://www.gnu.org address@hidden
Marcus Brinkmann The Hurd http://www.gnu.org/software/hurd/
address@hidden
http://www.marcus-brinkmann.de/
- deferred cancellation of ipc, Marcus Brinkmann, 2003/10/13
- Re: deferred cancellation of ipc, Niels Möller, 2003/10/14
- Re: deferred cancellation of ipc, Marcus Brinkmann, 2003/10/14
- Re: deferred cancellation of ipc, Niels Möller, 2003/10/14
- Re: deferred cancellation of ipc, Marcus Brinkmann, 2003/10/14
- Re: deferred cancellation of ipc, Niels Möller, 2003/10/14
- RE: deferred cancellation of ipc, Volkmar Uhlig, 2003/10/14
- Re: deferred cancellation of ipc, Marcus Brinkmann, 2003/10/14
- Re: deferred cancellation of ipc, Marcus Brinkmann, 2003/10/14
- RE: deferred cancellation of ipc, Volkmar Uhlig, 2003/10/14
- Re: deferred cancellation of ipc,
Marcus Brinkmann <=
- Re: deferred cancellation of ipc, Stefan Götz, 2003/10/15
- Re: deferred cancellation of ipc, Marcus Brinkmann, 2003/10/15
- Re: deferred cancellation of ipc, Marcus Brinkmann, 2003/10/14
- Re: deferred cancellation of ipc, Niels Möller, 2003/10/14
- Re: deferred cancellation of ipc, Marcus Brinkmann, 2003/10/14
- Re: deferred cancellation of ipc, Marcus Brinkmann, 2003/10/14