Messages in this thread | | | Date | Mon, 11 Apr 2005 15:17:23 -0700 | Subject | Re: [PATCH] Priority Lists for the RT mutex | From | Bill Huey (hui) <> |
| |
On Mon, Apr 11, 2005 at 10:57:37AM +0200, Ingo Molnar wrote: > > * Perez-Gonzalez, Inaky <inaky.perez-gonzalez@intel.com> wrote: > > > Let me re-phrase then: it is a must have only on PI, to make sure you > > don't have a loop when doing it. Maybe is a consequence of the > > algorithm I chose. -However- it should be possible to disable it in > > cases where you are reasonably sure it won't happen (such as kernel > > code). In any case, AFAIR, I still did not implement it. > > are there cases where userspace wants to disable deadlock-detection for > its own locks?
I'd disable it for userspace locks. There might be folks that want to implement userspace drivers, but I can't imagine it being 'ok' to have the kernel call out to userspace and have it block correctly. I would expect them to do something else that's less drastic.
> the deadlock detector in PREEMPT_RT is pretty much specialized for > debugging (it does all sorts of weird locking tricks to get the first > deadlock out, and to really report it on the console), but it ought to > be possible to make it usable for userspace-controlled locks as well.
If I understand things correctly, I'd let that be an RT app issue and the app folks should decided what is appropriate for their setup. If they need a deadlock detector they should decide on their own protocol. The kernel debugging issues are completely different.
That's my two cents.
bill
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |