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* Preempt Violation
@ 2004-07-17  0:06 Gabriel Devenyi
  2004-07-17  0:50 ` Lee Revell
  0 siblings, 1 reply; 3+ messages in thread
From: Gabriel Devenyi @ 2004-07-17  0:06 UTC (permalink / raw)
  To: ck, linux-kernel

This one looks particularly nasty.

20ms non-preemptible critical section violated 4 ms preempt threshold starting 
a                                                                                        
t sys_ioctl+0x42/0x260 and ending at sys_ioctl+0xbd/0x260
 [<c015881d>] sys_ioctl+0xbd/0x260
 [<c0116510>] dec_preempt_count+0x110/0x120
 [<c015881d>] sys_ioctl+0xbd/0x260
 [<c0103e95>] sysenter_past_esp+0x52/0x71

-- 
Gabriel Devenyi
devenyga@mcmaster.ca

^ permalink raw reply	[flat|nested] 3+ messages in thread
* RE: Preempt Violation
@ 2004-07-19  6:06 Zhu, Yi
  0 siblings, 0 replies; 3+ messages in thread
From: Zhu, Yi @ 2004-07-19  6:06 UTC (permalink / raw)
  To: Lee Revell, Gabriel Devenyi; +Cc: ck, linux-kernel

linux-kernel-owner@vger.kernel.org wrote:
> On Fri, 2004-07-16 at 20:06, Gabriel Devenyi wrote:
>> This one looks particularly nasty.
>> 
>> 20ms non-preemptible critical section violated 4 ms preempt
>> threshold starting a
> 
>> t sys_ioctl+0x42/0x260 and ending at sys_ioctl+0xbd/0x260
>> [<c015881d>] sys_ioctl+0xbd/0x260  [<c0116510>]
>> dec_preempt_count+0x110/0x120  [<c015881d>] sys_ioctl+0xbd/0x260
>> [<c0103e95>] sysenter_past_esp+0x52/0x71
> 
> Yes, it looks like there are serious issues with ioctl.
> 
> Are you using either of the recent patches to fully daemonize
> softirqs? This should help a lot.  I am using this one:
> 
> http://lkml.org/lkml/2004/7/13/125
> 
> It applied against 2.6.8-mm1, with only one PPC-specific reject, I
> use i386 so it doesn't matter. 
> 
> Here is another:
> 
> http://lkml.org/lkml/2004/7/13/152
> 
> Have not tested yet.
> 
> Lee

ioctl is called with the BKL held, which will disable preempt.
I don't think the patch helps.

Thanks,
-yi

^ permalink raw reply	[flat|nested] 3+ messages in thread

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2004-07-17  0:06 Preempt Violation Gabriel Devenyi
2004-07-17  0:50 ` Lee Revell
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2004-07-19  6:06 Zhu, Yi

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