Re: [patch] Real-Time Preemption, -RT-2.6.12-rc1-V0.7.41-07

Ingo Molnar
2005-04-01T05:23:17Z

* Steven Rostedt <rostedt@goodmis.org> wrote:

> > could you send me your latest patch for the bit-spin issue? My main
> > issue was cleanliness, so that the patch doesnt get stuck in the -RT
> > tree forever.
>
> I think that's the main problem. Without changing the design of the
> ext3 system, I don't think there is a clean patch. The implementation
> that I finally settled down with was to make the j_state and
> j_journal_head locks two global locks. I had to make a few
> modifications to some spots to avoid deadlocks, but this worked out
> well. The problem I was worried about was this causing too much
> overhead. So the ext3 buffers would have to contend with each other. I
> don't have any tests to see if this had too much of an impact.

yeah - i think Andrew said that a global lock at that particular place
might not be that much of an issue.

Ingo