NO_HZ FULL will not work in realtime-virtual-guest

[Yang, Tao Y]

Hi ALL,

               I am running the RHEL 7.1 in both host and guest for a low latency network
performance test.
               I use the realtime-virtual-host for the host and realtime-virtual-guest for
guest.
               These optimize really improve my network performance in the RFC 2544
throughput test.

               But I fund there are error in the guest OS, when I enable the nohz_full.
               Looks like the nohz_full can't be enable in the guest OS.
               Do we need remove the nohz_full in the realtime-virtual-guest for guest?



               Here is information from the Guest OS.
[root@localhost ~]# cat /proc/cmdline
BOOT_IMAGE=/vmlinuz-3.10.0-229.el7.x86_64 root=/dev/mapper/centos-root ro
rd.lvm.lv=centos/root rd.lvm.lv=centos/swap crashkernel=auto rhgb quiet
default_hugepagesz=1G hugepagesz=1G hugepages=2 nmi_watchdog=0 selinux=0 isolcpus=2-3
nohz_full=2-3 intel_pstate=disable nosoftlockup

Jul 28 09:59:46 localhost kernel: ------------[ cut here ]------------
Jul 28 09:59:46 localhost kernel: ------------[ cut here ]------------
Jul 28 09:59:46 localhost kernel: WARNING: at kernel/time/tick-sched.c:187
can_stop_full_tick+0x119/0x1e0()
Jul 28 09:59:46 localhost kernel: WARNING: at kernel/time/tick-sched.c:187
can_stop_full_tick+0x119/0x1e0()
Jul 28 09:59:46 localhost kernel: NO_HZ FULL will not work with unstable sched clock
Jul 28 09:59:46 localhost kernel: NO_HZ FULL will not work with unstable sched clock
Jul 28 09:59:46 localhost kernel: Modules linked in:
Jul 28 09:59:46 localhost kernel:
Jul 28 09:59:46 localhost kernel: Modules linked in:
Jul 28 09:59:46 localhost kernel: CPU: 3 PID: 26 Comm: migration/3 Not tainted
3.10.0-229.el7.x86_64 #1
Jul 28 09:59:46 localhost kernel: CPU: 2 PID: 22 Comm: migration/2 Not tainted
3.10.0-229.el7.x86_64 #1
Jul 28 09:59:46 localhost kernel: Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS rel-1.8.1-0-g4adadbd-20150316_085822-nilsson.home.kraxel.org 04/01/2014
Jul 28 09:59:46 localhost kernel: Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS rel-1.8.1-0-g4adadbd-20150316_085822-nilsson.home.kraxel.org 04/01/2014
Jul 28 09:59:46 localhost kernel: ffff88013fd83ee8
Jul 28 09:59:46 localhost kernel: ffff88013fd03ee8
Jul 28 09:59:46 localhost kernel: 00000000ed88478b
Jul 28 09:59:46 localhost kernel: 000000007151008b
Jul 28 09:59:46 localhost kernel: ffff88013fd83ea0
Jul 28 09:59:46 localhost kernel: ffff88013fd03ea0
Jul 28 09:59:46 localhost kernel: ffffffff81604b0a
Jul 28 09:59:46 localhost kernel:
Jul 28 09:59:46 localhost kernel: ffffffff81604b0a
Jul 28 09:59:46 localhost kernel: ffff88013fd83ed8
Jul 28 09:59:46 localhost kernel: ffff88013fd03ed8
Jul 28 09:59:46 localhost kernel: ffffffff8106e34b
Jul 28 09:59:46 localhost kernel: ffffffff8106e34b
Jul 28 09:59:46 localhost kernel: ffff88013fd8da40
Jul 28 09:59:46 localhost kernel: ffff88013fd0da40
Jul 28 09:59:46 localhost kernel: 0000000000000003
Jul 28 09:59:46 localhost kernel:
Jul 28 09:59:46 localhost kernel: 0000000000000002
Jul 28 09:59:46 localhost kernel: ffff880036cd7d01
Jul 28 09:59:46 localhost kernel: ffff880036cd7d01
Jul 28 09:59:46 localhost kernel: 0000000000000282
Jul 28 09:59:46 localhost kernel: 0000000000000282
Jul 28 09:59:46 localhost kernel: ffff880139beffd8
Jul 28 09:59:46 localhost kernel: ffff880139bdbfd8
Jul 28 09:59:46 localhost kernel: ffff88013fd83f40
Jul 28 09:59:46 localhost kernel:
Jul 28 09:59:46 localhost kernel: ffff88013fd03f40
Jul 28 09:59:46 localhost kernel: Call Trace:
Jul 28 09:59:46 localhost kernel: Call Trace:
Jul 28 09:59:46 localhost kernel: <IRQ>
Jul 28 09:59:46 localhost kernel: <IRQ>
Jul 28 09:59:46 localhost kernel: [<ffffffff81604b0a>] dump_stack+0x19/0x1b
Jul 28 09:59:46 localhost kernel: [<ffffffff81604b0a>] dump_stack+0x19/0x1b
Jul 28 09:59:46 localhost kernel: [<ffffffff8106e34b>]
warn_slowpath_common+0x6b/0xb0
Jul 28 09:59:46 localhost kernel: [<ffffffff8106e34b>]
warn_slowpath_common+0x6b/0xb0
Jul 28 09:59:46 localhost kernel: [<ffffffff8106e3ec>] warn_slowpath_fmt+0x5c/0x80
Jul 28 09:59:46 localhost kernel: [<ffffffff8106e3ec>] warn_slowpath_fmt+0x5c/0x80
Jul 28 09:59:46 localhost kernel: [<ffffffff810d0eb9>]
can_stop_full_tick+0x119/0x1e0
Jul 28 09:59:46 localhost kernel: [<ffffffff810d0eb9>]
can_stop_full_tick+0x119/0x1e0
Jul 28 09:59:46 localhost kernel: [<ffffffff810d1200>] tick_nohz_irq_exit+0x80/0xb0
Jul 28 09:59:46 localhost kernel: [<ffffffff810d1200>] tick_nohz_irq_exit+0x80/0xb0
Jul 28 09:59:46 localhost kernel: [<ffffffff81077f0b>] irq_exit+0x8b/0x120
Jul 28 09:59:46 localhost kernel: [<ffffffff81077f0b>] irq_exit+0x8b/0x120
Jul 28 09:59:46 localhost kernel: [<ffffffff81616fd5>]
smp_apic_timer_interrupt+0x45/0x60
Jul 28 09:59:46 localhost kernel: [<ffffffff81616fd5>]
smp_apic_timer_interrupt+0x45/0x60
Jul 28 09:59:46 localhost kernel: [<ffffffff8161569d>]
apic_timer_interrupt+0x6d/0x80
Jul 28 09:59:46 localhost kernel: [<ffffffff8161569d>]
apic_timer_interrupt+0x6d/0x80
Jul 28 09:59:46 localhost kernel: <EOI>
Jul 28 09:59:46 localhost kernel: <EOI>
Jul 28 09:59:46 localhost kernel: [<ffffffff810f2952>] ? multi_cpu_stop+0x82/0xf0
Jul 28 09:59:46 localhost kernel: [<ffffffff810f2952>] ? multi_cpu_stop+0x82/0xf0
Jul 28 09:59:46 localhost kernel: [<ffffffff810f28d0>] ?
cpu_stop_should_run+0x50/0x50
Jul 28 09:59:46 localhost kernel: [<ffffffff810f28d0>] ?
cpu_stop_should_run+0x50/0x50
Jul 28 09:59:46 localhost kernel: [<ffffffff810f2b58>]
cpu_stopper_thread+0x88/0x160
Jul 28 09:59:46 localhost kernel: [<ffffffff810f2b58>]
cpu_stopper_thread+0x88/0x160
Jul 28 09:59:46 localhost kernel: [<ffffffff810a478e>] ?
finish_task_switch+0xee/0x170
Jul 28 09:59:46 localhost kernel: [<ffffffff810a478e>] ?
finish_task_switch+0xee/0x170
Jul 28 09:59:46 localhost kernel: [<ffffffff81609925>] ? __schedule+0x2c5/0x7b0
Jul 28 09:59:46 localhost kernel: [<ffffffff81609925>] ? __schedule+0x2c5/0x7b0
Jul 28 09:59:46 localhost kernel: [<ffffffff8109fdaf>] smpboot_thread_fn+0xff/0x1a0
Jul 28 09:59:46 localhost kernel: [<ffffffff8109fdaf>] smpboot_thread_fn+0xff/0x1a0
Jul 28 09:59:46 localhost kernel: [<ffffffff8109fcb0>] ? lg_global_unlock+0xc0/0xc0
Jul 28 09:59:46 localhost kernel: [<ffffffff8109fcb0>] ? lg_global_unlock+0xc0/0xc0
Jul 28 09:59:46 localhost kernel: [<ffffffff8109739f>] kthread+0xcf/0xe0
Jul 28 09:59:46 localhost kernel: [<ffffffff8109739f>] kthread+0xcf/0xe0
Jul 28 09:59:46 localhost kernel: [<ffffffff810972d0>] ?
kthread_create_on_node+0x140/0x140
Jul 28 09:59:46 localhost kernel: [<ffffffff810972d0>] ?
kthread_create_on_node+0x140/0x140
Jul 28 09:59:46 localhost kernel: [<ffffffff8161497c>] ret_from_fork+0x7c/0xb0
Jul 28 09:59:46 localhost kernel: [<ffffffff8161497c>] ret_from_fork+0x7c/0xb0
Jul 28 09:59:46 localhost kernel: [<ffffffff810972d0>] ?
kthread_create_on_node+0x140/0x140
Jul 28 09:59:46 localhost kernel: [<ffffffff810972d0>] ?
kthread_create_on_node+0x140/0x140
Jul 28 09:59:46 localhost kernel: ---[ end trace 53841d7ee8fd2cd6 ]---
Jul 28 09:59:46 localhost kernel: ---[ end trace 53841d7ee8fd2cd7 ]---