xen-devel

[Top] [All Lists]

Re: [Xen-devel] [PATCH] Fix deadlock in schedule.c at TRACE mode

from [Atsushi SAKAI]

[Permanent Link][Original]

To:	NISHIGUCHI Naoki <nisiguti@xxxxxxxxxxxxxx>
Subject:	Re: [Xen-devel] [PATCH] Fix deadlock in schedule.c at TRACE mode
From:	Atsushi SAKAI <sakaia@xxxxxxxxxxxxxx>
Date:	Thu, 24 Apr 2008 14:42:53 +0900
Cc:	xen-devel@xxxxxxxxxxxxxxxxxxx
Delivery-date:	Wed, 23 Apr 2008 22:43:35 -0700
Envelope-to:	www-data@xxxxxxxxxxxxxxxxxx
In-reply-to:	<48100DF2.5000605@xxxxxxxxxxxxxx>
List-help:	<mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id:	Xen developer discussion <xen-devel.lists.xensource.com>
List-post:	<mailto:xen-devel@lists.xensource.com>
List-subscribe:	<http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe:	<http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
References:	<48100DF2.5000605@xxxxxxxxxxxxxx>
Sender:	xen-devel-bounces@xxxxxxxxxxxxxxxxxxx

Hi, Naoki

I have two questions about this.

1)How to reproduce your deadlock ?
  Would you give me your test environment to reproduce this deadlock?
  Is it easily reproduced by running xenmon.py or xentrace 
  with one or two guest domain(s)?
　or Any additional condition needed?

2)About fixing code,
  I think __trace_var() should fix for this issue not schedule()
  This issue cannot be fixed by modify the __trace_var()?

Thanks
Atsushi SAKAI

NISHIGUCHI Naoki <nisiguti@xxxxxxxxxxxxxx> wrote:

> Hi,
> 
> In schedule.c, schedule() and sched_adjust() call trace functions during
> acquiring lock of schedule_lock in each cpu's schedule_data. When trace
> buffers are enabled, the trace function (__trace_var()) may call
> vcpu_wake() by calling send_guest_global_virq(). In the case, a deadlock
> occurs when acquiring lock of schedule_lock.
> 
> Attached patch fixes this problem.
> 
> Signed-off-by: Naoki Nishiguchi <nisiguti@xxxxxxxxxxxxxx>
> 
> Regards,
> Naoki Nishiguchi

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel

[More with this subject...]

<Prev in Thread]	Current Thread	[Next in Thread>
[Xen-devel] [PATCH] Fix deadlock in schedule.c at TRACE mode, NISHIGUCHI Naoki Re: [Xen-devel] [PATCH] Fix deadlock in schedule.c at TRACE mode, Atsushi SAKAI <= Re: [Xen-devel] [PATCH] Fix deadlock in schedule.c at TRACE mode, NISHIGUCHI Naoki Re: [Xen-devel] [PATCH] Fix deadlock in schedule.c at TRACE mode, Keir Fraser

Previous by Date:	[Xen-devel] [PATCH] warning fix, Kouya Shimura
Next by Date:	Re: [Xen-devel] [PATCH] Fix deadlock in schedule.c at TRACE mode, NISHIGUCHI Naoki
Previous by Thread:	[Xen-devel] [PATCH] Fix deadlock in schedule.c at TRACE mode, NISHIGUCHI Naoki
Next by Thread:	Re: [Xen-devel] [PATCH] Fix deadlock in schedule.c at TRACE mode, NISHIGUCHI Naoki
Indexes:	[Date] [Thread] [Top] [All Lists]