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

[Ingo Molnar]

* Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> Well, here it finally is. There's still things I don't like about it. 
> But it seems to work, and that's the important part.
> 
> I had to reluctantly add two items to the task_struct.  I was hoping 
> to avoid that. But because of race conditions it seemed to be the only 
> way.

well it's not a big problem, and we avoided having to add flags to the 
rt_lock structure, which is the important issue.

your patch looks good, i've added it to my tree and have uploaded the 
-26-00 patch. It boots fine on my testbox, except for some new messages:

 knodemgrd_0/902: BUG in __down_complete at kernel/rt.c:1568
  [<c0103956>] dump_stack+0x23/0x25 (20)
  [<c0130dcd>] down_trylock+0x1fb/0x200 (48)
  [<c0364ee2>] nodemgr_host_thread+0xd0/0x17b (48)
  [<c0100d4d>] kernel_thread_helper+0x5/0xb (136249364)
 ---------------------------
 | preempt count: 00000001 ]
 | 1-level deep critical section nesting:
 ----------------------------------------
 .. [<c0133a75>] .... print_traces+0x1b/0x52
 .....[<c0103956>] ..   ( <= dump_stack+0x23/0x25)

this goes away if i revert your patch. It seems the reason is that 
trylock hasnt been updated to use the pending-owner logic?

	Ingo
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