Re: [patch] Real-Time Preemption, -VP-2.6.9-rc4-mm1-U4

[Florian Schmidt]

On Sat, 16 Oct 2004 17:33:44 +0200
Ingo Molnar <mingo@xxxxxxx> wrote:

> 
> i have released the -U4 PREEMPT_REALTIME patch:
> 
>    http://redhat.com/~mingo/voluntary-preempt/voluntary-preempt-2.6.9-rc4-mm1-U4
> 
> this is a fixes-only release, and it is still experimental code.

Hi,

the cpu mhz issue seems to be fixed:

~$ uname -a
Linux mango.fruits.de 2.6.9-rc4-mm1-RT-U4-RT #1 Sun Oct 17 17:48:48 CEST 2004 i686 GNU/Linux
~$ cat /proc/cpuinfo |grep MHz
cpu MHz         : 1195.145
mango:/usr/src/linux-2.6.9-rc4-mm1-VP-U4# grep REALTIME .config
CONFIG_PREEMPT_REALTIME=y


Might of course be coincidence. Will report as soon as i see the 0.001 Mhz
pop up again.

I saw one of these in /var/log/syslog:

Oct 17 18:53:52 mango kernel: PCI: Found IRQ 3 for device 0000:00:0f.0
Oct 17 18:53:52 mango kernel: Debug: sleeping function called from invalid context modprobe(109) at kernel/mutex.c:25
Oct 17 18:53:52 mango kernel: in_atomic():0 [00000000], irqs_disabled():1
Oct 17 18:53:52 mango kernel:  [print_context_stack+78/112] dump_stack+0x1e/0x20
Oct 17 18:53:52 mango kernel:  [sinbin_release_fn+536/864] __might_sleep+0xb8/0xd0
Oct 17 18:53:52 mango kernel:  [__create_workqueue+35/320] _mutex_lock+0x23/0x60
Oct 17 18:53:52 mango kernel:  [__create_workqueue+145/320] _mutex_lock_irqsave+0x11/0x20
Oct 17 18:53:52 mango kernel:  [pg0+809943061/1069765632] get_time_pit+0x15/0x50 [gameport]
Oct 17 18:53:52 mango kernel:  [pg0+809943199/1069765632] gameport_measure_speed+0x4f/0x100 [gameport]
Oct 17 18:53:52 mango kernel:  [pg0+809943550/1069765632] gameport_register_port+0x2e/0x40 [gameport]
Oct 17 18:53:52 mango kernel:  [pg0+809931156/1069765632] snd_card_cs46xx_probe+0x194/0x250 [snd_cs46xx]
Oct 17 18:53:52 mango kernel:  [crypto_unregister_alg+43/192] pci_device_probe_static+0x4b/0x60
Oct 17 18:53:52 mango kernel:  [crypto_unregister_alg+104/192] __pci_device_probe+0x28/0x30
Oct 17 18:53:52 mango kernel:  [crypto_unregister_alg+156/192] pci_device_probe+0x2c/0x50
Oct 17 18:53:52 mango kernel:  [take_over_console+605/1248] bus_match+0x3d/0x70
Oct 17 18:53:52 mango kernel:  [take_over_console+906/1248] driver_attach+0x5a/0x90
Oct 17 18:53:52 mango kernel:  [do_blank_screen+608/688] bus_add_driver+0xa0/0xd0
Oct 17 18:53:52 mango kernel:  [con_set_cmap+1/64] driver_register+0x31/0x40
Oct 17 18:53:52 mango kernel:  [scatterwalk_pagedone+18/96] pci_register_driver+0x42/0x50
Oct 17 18:53:52 mango kernel:  [pg0+809931362/1069765632] alsa_card_cs46xx_init+0x12/0x30 [snd_cs46xx]
Oct 17 18:53:52 mango kernel:  [__kfifo_put+65/208] sys_init_module+0x1f1/0x2d0
Oct 17 18:53:52 mango kernel:  [need_resched+36/37] syscall_call+0x7/0xb
Oct 17 18:53:52 mango kernel: preempt count: 00000001
Oct 17 18:53:52 mango kernel: . 1-level deep critical section nesting:
Oct 17 18:53:52 mango kernel: .. entry 1: print_traces+0x12/0x40 / (dump_stack+0x1e/0x20)
Oct 17 18:53:52 mango kernel: 

This seems to be related to modprobe'ing snd-cs46xx

flo

p.s.: attached is the .config of this kernel.

Attachment: .config
Description: Binary data