[dtrace-discuss] kernel pause/resume

Adam Leventhal
Wed, 10 Aug 2005 23:57:40 -0000

On Wed, Aug 10, 2005 at 04:27:30PM -0700, Michael Bergknoff
wrote:
> I should have mentioned that I looked into chill but the manual said
> it''s not safe to chill for more than a few hundred milliseconds
due to
> issues with interrupts in the probed context. I''m looking at
starting
> one thread and pausing for minutes before resuming in another thread. As
> for stop() I believe that stops on the way out of the kernel which is
> not what I need.

We don''t let you stop a thread at an arbitrary place in the kernel
because it simply isn''t safe. For example, you could end up backing up
the entire system on some kernel mutex which the stopped thread holds,
and there would be no way to restart the system. Even less than
arbitrary freedom to stop thread in the kernel would be difficult to
implement in a provably safe manner.

Adam

--
Adam Leventhal, Solaris Kernel Development       http://blogs.sun.com/ahl