From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Steve Wise" Subject: RXE and ib_write_bw Date: Wed, 15 Jun 2016 16:26:31 -0500 Message-ID: <01e001d1c74c$961cd950$c2568bf0$@opengridcomputing.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Return-path: Content-Language: en-us Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: 'Moni Shoua' Cc: 'Doug Ledford' , 'linux-rdma' , 'Matan Barak' , 'Majd Dibbiny' , 'Liran Liss' , 'Kamal Heib' , 'Amir Vadai' , 'Leon Romanovsky' List-Id: linux-rdma@vger.kernel.org Hey Moni, When I run ib_write_bw, I get this logged on one or sometimes both nodes. I think RXE is perhaps doing too much in the interrupt context or in its tasklet? The test is: ib_write_bw -a -R -d rxe0 --report_gbits --bidir 10.0.1.14 The dmesg log: INFO: rcu_sched self-detected stall on CPU 8-...: (1 GPs behind) idle=49f/140000000000001/0 softirq=16690/16690 fqs=6706 INFO: rcu_sched detected stalls on CPUs/tasks: 8-...: (1 GPs behind) idle=49f/140000000000001/0 softirq=16690/16690 fqs=6706 (detected by 13, t=21008 jiffies, g=17642, c=17641, q=4090) Task dump for CPU 8: ksoftirqd/8 R running task 0 48 2 0x10000008 ffffffff00000100 ffff88107861ed80 ffffffff81a050f0 0000000000000006 0000000000000100 ffff881078627e68 ffffffff8161abbb 0420804000000000 ffff881078624008 000000010018d17d 0000000a7861ed80 ffffffff81a050f0 Call Trace: [] ? __do_softirq+0xeb/0x2d8 [] ? smpboot_create_threads+0x80/0x80 [] ? schedule+0x40/0xb0 [] ? smpboot_create_threads+0x80/0x80 [] ? run_ksoftirqd+0x1d/0x40 [] ? smpboot_thread_fn+0x10c/0x160 [] ? kthread+0xcc/0xf0 [] ? schedule_tail+0x1e/0xc0 [] ? ret_from_fork+0x1f/0x40 [] ? kthread_freezable_should_stop+0x70/0x70 (t=21081 jiffies g=17642 c=17641 q=4090) Task dump for CPU 8: ksoftirqd/8 R running task 0 48 2 0x10000008 0000000000000009 ffff88107f403ba8 ffffffff8108956d ffff881078bfa040 0000000000000008 000000000000000f 0000000000000006 0000000000000008 ffffffff81a48240 ffff88107f403bc8 ffffffff8108960f ffff88107f403bc8 Call Trace: [] sched_show_task+0xbd/0x120 [] dump_cpu_task+0x3f/0x50 [] rcu_dump_cpu_stacks+0x7c/0xb0 [] print_cpu_stall+0xf1/0x150 [] check_cpu_stall+0x110/0x120 [] ? trace_buffer_unlock_commit_regs+0x61/0x80 [] ? trace_event_buffer_commit+0x146/0x1d0 [] ? trace_event_raw_event_softirq+0x5d/0xa0 [] rcu_check_callbacks+0xe8/0x330 [] ? __raise_softirq_irqoff+0x72/0x80 [] ? acct_account_cputime+0x1c/0x20 [] ? account_system_time+0x90/0x130 [] update_process_times+0x39/0x70 [] tick_sched_handle+0x3a/0x50 [] tick_sched_timer+0x52/0xa0 [] __run_hrtimer+0x77/0x1d0 [] ? tick_nohz_handler+0xc0/0xc0 [] ? trace_event_raw_event_softirq+0x5d/0xa0 [] ? ktime_get+0x4c/0xc0 [] __hrtimer_run_queues+0x67/0x90 [] hrtimer_interrupt+0x9b/0x170 [] local_apic_timer_interrupt+0x39/0x60 [] smp_apic_timer_interrupt+0x41/0x60 [] apic_timer_interrupt+0x7f/0x90 [] ? rxe_requester+0x252/0x780 [ib_rxe] [] ? rxe_requester+0x233/0x780 [ib_rxe] [] ? trace_event_buffer_commit+0x146/0x1d0 [] rxe_do_task+0x59/0x100 [ib_rxe] [] tasklet_action+0xa3/0xc0 [] __do_softirq+0xeb/0x2d8 [] ? smpboot_create_threads+0x80/0x80 [] ? schedule+0x40/0xb0 [] ? smpboot_create_threads+0x80/0x80 [] run_ksoftirqd+0x1d/0x40 [] smpboot_thread_fn+0x10c/0x160 [] kthread+0xcc/0xf0 [] ? schedule_tail+0x1e/0xc0 [] ret_from_fork+0x1f/0x40 [] ? kthread_freezable_should_stop+0x70/0x70 -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html