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: Wed, 25 Jan 2012 22:14:33 +0100 [thread overview]
Message-ID: <4F2070B9.2000104@numascale.com> (raw)
In-Reply-To: <20120125181441.GD2849@linux.vnet.ibm.com>
On 1/25/2012 19:14, Paul E. McKenney wrote:
[]
>
> So, it would be very interesting to add the values rdp->mynode->gpnum
> and rdp->mynode->completed to your list, perhaps labeling them something
> like "rng" and "rnc" respectively.
>
I added them to the printout. This time I ran with NR_CPUS=512 so there's only two levels but we see more qsmask bits set on the root node :
[ 738.329672] CPU 48, treason uncloaked, rsp @ ffffffff81a1cd80 (rcu_sched), gpnum=10568, completed=10567, n_force_qs=69, n_force_qs_lh=0, n_force_qs_ngp=0, rnp @ ffffffff81a1cd80, qsmask=0x1f
[ 738.330137] 0 ffff8803f840d660 c=10567 g=10568 pq=1 pgp=10568 qp=0 of=0 ri=66 ql=1 qs=..W. b=10 ci=158068 co=0 ca=0 rng=10568 rnc=10567
[ 738.330137] 12 ffff880bd040d660 c=10567 g=10568 pq=1 pgp=10568 qp=0 of=1 ri=0 ql=0 qs=.... b=10 ci=715 co=0 ca=0 rng=10568 rnc=10567
[ 738.330137] 24 ffff8813d040d660 c=10567 g=10568 pq=1 pgp=10568 qp=0 of=0 ri=0 ql=0 qs=.... b=10 ci=484 co=0 ca=0 rng=10568 rnc=10567
[ 738.330137] 36 ffff881bd040d660 c=10567 g=10568 pq=1 pgp=10568 qp=0 of=1 ri=0 ql=0 qs=.... b=10 ci=369 co=0 ca=0 rng=10568 rnc=10567
[ 738.330137] 48 ffff8823d040d660 c=10567 g=10567 pq=1 pgp=10567 qp=0 of=0 ri=0 ql=28 qs=.RWD b=10 ci=9292 co=0 ca=0 rng=10568 rnc=10567
[ 738.330137] 60 ffff882bd040d660 c=10567 g=10568 pq=1 pgp=10568 qp=0 of=0 ri=1 ql=0 qs=.... b=10 ci=32 co=0 ca=0 rng=10568 rnc=10567
[ 738.330137] 72 ffff8833d040d660 c=10567 g=10568 pq=1 pgp=10568 qp=0 of=0 ri=0 ql=0 qs=.... b=10 ci=43 co=0 ca=0 rng=10568 rnc=10567
[ 738.330137] ------------[ cut here ]------------
[ 738.330137] WARNING: at kernel/rcutree_plugin.h:1011 rcu_preempt_check_blocked_tasks+0x27/0x30()
[ 738.330137] Hardware name: H8QI6
[ 738.330137] Modules linked in: rcutorture
[ 738.330137] Pid: 4611, comm: rcu_torture_rea Not tainted 3.2.1-numaconnect10+ #68
[ 738.330137] Call Trace:
[ 738.330137] <IRQ> [<ffffffff810bb327>] ? rcu_preempt_check_blocked_tasks+0x27/0x30
[ 738.330137] [<ffffffff8106f47b>] warn_slowpath_common+0x8b/0xc0
[ 738.330137] [<ffffffff8106f4c5>] warn_slowpath_null+0x15/0x20
[ 738.330137] [<ffffffff810bb327>] rcu_preempt_check_blocked_tasks+0x27/0x30
[ 738.330137] [<ffffffff810bb43d>] rcu_start_gp+0x10d/0x1b0
[ 738.330137] [<ffffffff810bc04b>] __rcu_process_callbacks+0x8b/0xd0
[ 738.330137] [<ffffffff810bc8b0>] rcu_process_callbacks+0x20/0x40
[ 738.330137] [<ffffffff810757fd>] __do_softirq+0x9d/0x140
[ 738.330137] [<ffffffffa0001510>] ? rcu_torture_shuffle+0x80/0x80 [rcutorture]
[ 738.330137] [<ffffffff815d982c>] call_softirq+0x1c/0x30
[ 738.330137] [<ffffffff8103451a>] do_softirq+0x4a/0x80
[ 738.330137] [<ffffffff81075b73>] irq_exit+0x43/0x60
[ 738.330137] [<ffffffff8104aee5>] smp_apic_timer_interrupt+0x45/0x60
[ 738.330137] [<ffffffffa0001c60>] ? rcu_sync_torture_deferred_free+0xd0/0xd0 [rcutorture]
[ 738.330137] [<ffffffff815d834b>] apic_timer_interrupt+0x6b/0x70
[ 738.330137] <EOI> [<ffffffff815d4d79>] ? __schedule+0x349/0x710
[ 738.330137] [<ffffffff810618d5>] ? update_curr+0x85/0xd0
[ 738.330137] [<ffffffff8107b816>] ? lock_timer_base+0x36/0x70
[ 738.330137] [<ffffffff8107ba92>] ? mod_timer+0xf2/0x1d0
[ 738.330137] [<ffffffffa0001510>] ? rcu_torture_shuffle+0x80/0x80 [rcutorture]
[ 738.330137] [<ffffffff815d541a>] schedule+0x3a/0x60
[ 738.330137] [<ffffffffa0001640>] rcu_torture_reader+0x130/0x230 [rcutorture]
[ 738.330137] [<ffffffffa0001dc0>] ? rcu_torture_writer+0x160/0x160 [rcutorture]
[ 738.330137] [<ffffffffa0001510>] ? rcu_torture_shuffle+0x80/0x80 [rcutorture]
[ 738.330137] [<ffffffff8108a716>] kthread+0x96/0xa0
[ 738.330137] [<ffffffff815d9734>] kernel_thread_helper+0x4/0x10
[ 738.330137] [<ffffffff8108a680>] ? kthread_stop+0x70/0x70
[ 738.330137] [<ffffffff815d9730>] ? gs_change+0xb/0xb
[ 738.330137] ---[ end trace e8e520cce35c7626 ]---
[ 738.330137] CPU 48, treason uncloaked, rsp @ ffffffff81a1cd80 (rcu_sched), gpnum=10568, completed=10567, n_force_qs=70, n_force_qs_lh=250, n_force_qs_ngp=0, rnp @ ffffffff81a1d180, qsmask=0x1
[ 738.330137] 0 ffff8803f840d660 c=10567 g=10568 pq=1 pgp=10568 qp=0 of=0 ri=67 ql=1 qs=..W. b=10 ci=158068 co=0 ca=0 rng=10568 rnc=10567
[ 738.330137] 12 ffff880bd040d660 c=10567 g=10568 pq=1 pgp=10568 qp=0 of=1 ri=1 ql=1 qs=N... b=10 ci=715 co=0 ca=0 rng=10568 rnc=10567
[ 738.330137] 24 ffff8813d040d660 c=10567 g=10568 pq=1 pgp=10568 qp=0 of=0 ri=1 ql=1 qs=N... b=10 ci=484 co=0 ca=0 rng=10568 rnc=10567
[ 738.330137] 36 ffff881bd040d660 c=10567 g=10568 pq=1 pgp=10568 qp=0 of=1 ri=1 ql=1 qs=N... b=10 ci=369 co=0 ca=0 rng=10568 rnc=10567
[ 738.330137] 48 ffff8823d040d660 c=10567 g=10567 pq=1 pgp=10567 qp=0 of=0 ri=0 ql=28 qs=.RWD b=10 ci=9292 co=0 ca=0 rng=10568 rnc=10567
[ 738.330137] 60 ffff882bd040d660 c=10567 g=10568 pq=1 pgp=10568 qp=0 of=0 ri=1 ql=0 qs=.... b=10 ci=32 co=0 ca=0 rng=10568 rnc=10567
[ 738.330137] 72 ffff8833d040d660 c=10567 g=10568 pq=1 pgp=10568 qp=0 of=0 ri=0 ql=0 qs=.... b=10 ci=43 co=0 ca=0 rng=10568 rnc=10567
Kind regards,
--
Steffen Persvold, Chief Architect NumaChip
Numascale AS - www.numascale.com
Tel: +47 92 49 25 54 Skype: spersvold
next prev parent reply other threads:[~2012-01-25 21:14 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 [this message]
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
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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