From: Steffen Persvold <sp@numascale.com>
To: paulmck@linux.vnet.ibm.com
Cc: Daniel J Blueman <daniel@numascale-asia.com>,
Dipankar Sarma <dipankar@in.ibm.com>,
linux-kernel@vger.kernel.org, x86@kernel.org
Subject: Re: RCU qsmask !=0 warnings on large-SMP...
Date: Thu, 26 Jan 2012 16:04:37 +0100 [thread overview]
Message-ID: <4F216B85.7010208@numascale.com> (raw)
In-Reply-To: <20120126015843.GN2849@linux.vnet.ibm.com>
On 1/26/2012 02:58, Paul E. McKenney wrote:
> On Wed, Jan 25, 2012 at 11:48:58PM +0100, Steffen Persvold wrote:
[]
>
> This looks like it will produce useful information, but I am not seeing
> output from it below.
>
> Thanx, Paul
>
>> This run it was CPU24 that triggered the issue :
>>
This line is the printout for the root level :
>> [ 231.572688] CPU 24, treason uncloaked, rsp @ ffffffff81a1cd80 (rcu_sched), rnp @ ffffffff81a1cd80(r) qsmask=0x1f, c=5132 g=5132 nc=5132 ng=5133 sc=5132 sg=5133 mc=5132 mg=5133
(this is the WARN_ON printout) :
>> [ 231.576167] ------------[ cut here ]------------
>> [ 231.576167] WARNING: at kernel/rcutree_plugin.h:1011 rcu_preempt_check_blocked_tasks+0x27/0x30()
>> [ 231.576167] Hardware name: H8QI6
>> [ 231.576167] Modules linked in: rcutorture
>> [ 231.576167] Pid: 4603, comm: rcu_torture_rea Not tainted 3.2.1-numaconnect10+ #77
>> [ 231.576167] Call Trace:
>> [ 231.576167]<IRQ> [<ffffffff810bb217>] ? rcu_preempt_check_blocked_tasks+0x27/0x30
>> [ 231.576167] [<ffffffff8106f47b>] warn_slowpath_common+0x8b/0xc0
>> [ 231.576167] [<ffffffff8106f4c5>] warn_slowpath_null+0x15/0x20
>> [ 231.576167] [<ffffffff810bb217>] rcu_preempt_check_blocked_tasks+0x27/0x30
>> [ 231.576167] [<ffffffff810bb330>] rcu_start_gp+0x110/0x1b0
>> [ 231.576167] [<ffffffff810bbf3b>] __rcu_process_callbacks+0x8b/0xd0
>> [ 231.576167] [<ffffffff810bc7a0>] rcu_process_callbacks+0x20/0x40
>> [ 231.576167] [<ffffffff8107580d>] __do_softirq+0x9d/0x140
>> [ 231.576167] [<ffffffff815d982c>] call_softirq+0x1c/0x30
>> [ 231.576167] [<ffffffff8103451a>] do_softirq+0x4a/0x80
>> [ 231.576167] [<ffffffff81075b83>] irq_exit+0x43/0x60
>> [ 231.576167] [<ffffffff8104aed5>] smp_apic_timer_interrupt+0x45/0x60
>> [ 231.576167] [<ffffffff815d834b>] apic_timer_interrupt+0x6b/0x70
>> [ 231.576167]<EOI> [<ffffffff81067aa9>] ? finish_task_switch+0x59/0xc0
>> [ 231.576167] [<ffffffff815d4d37>] __schedule+0x337/0x710
>> [ 231.576167] [<ffffffff81090425>] ? sched_clock_local+0x15/0x80
>> [ 231.576167] [<ffffffff8107b826>] ? lock_timer_base+0x36/0x70
>> [ 231.576167] [<ffffffff8107baa2>] ? mod_timer+0xf2/0x1d0
>> [ 231.576167] [<ffffffffa0001510>] ? rcu_torture_shuffle+0x80/0x80 [rcutorture]
>> [ 231.576167] [<ffffffff815d53ea>] schedule+0x3a/0x60
>> [ 231.576167] [<ffffffffa0001640>] rcu_torture_reader+0x130/0x230 [rcutorture]
>> [ 231.576167] [<ffffffffa0001dc0>] ? rcu_torture_writer+0x160/0x160 [rcutorture]
>> [ 231.576167] [<ffffffffa0001510>] ? rcu_torture_shuffle+0x80/0x80 [rcutorture]
>> [ 231.576167] [<ffffffff8108a726>] kthread+0x96/0xa0
>> [ 231.576167] [<ffffffff815d9734>] kernel_thread_helper+0x4/0x10
>> [ 231.576167] [<ffffffff8108a690>] ? kthread_stop+0x70/0x70
>> [ 231.576167] [<ffffffff815d9730>] ? gs_change+0xb/0xb
>> [ 231.576167] ---[ end trace 828c8d7afbd02d1b ]---
>>
I didn't include the leaf node printout, but the counters were
indentical to the root printout (with the exception of the rnp address
and qsmask of course).
Cheers,
--
Steffen Persvold, Chief Architect NumaChip
Numascale AS - www.numascale.com
Tel: +47 92 49 25 54 Skype: spersvold
next prev parent reply other threads:[~2012-01-26 15:04 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-01-25 9:44 RCU qsmask !=0 warnings on large-SMP Daniel J Blueman
2012-01-25 14:00 ` Paul E. McKenney
2012-01-25 14:18 ` Steffen Persvold
2012-01-25 18:14 ` Paul E. McKenney
2012-01-25 20:35 ` Steffen Persvold
2012-01-25 21:51 ` Paul E. McKenney
2012-01-25 22:51 ` Steffen Persvold
2012-01-26 1:57 ` Paul E. McKenney
2012-01-25 21:14 ` Steffen Persvold
2012-01-25 21:34 ` Paul E. McKenney
2012-01-25 22:48 ` Steffen Persvold
2012-01-26 1:58 ` Paul E. McKenney
2012-01-26 15:04 ` Steffen Persvold [this message]
2012-01-26 19:26 ` Paul E. McKenney
2012-01-27 11:09 ` Steffen Persvold
2012-01-29 6:09 ` Paul E. McKenney
2012-01-30 16:15 ` Paul E. McKenney
2012-01-31 17:33 ` Steffen Persvold
2012-01-31 17:38 ` Paul E. McKenney
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