22 Jan
2014
22 Jan
'14
1:39 p.m.
Hi,
there are 2 things I don't understand.
1. Linux-Rt and TSC
===================
All Rt kernels for all Linux distros I use seem to have an issue
regarding to TSC.
I wonder what to do, to get rid of those messages, IOW how to fix the
issue.
E.g. Debian 32-bit architecture
root@debi386:/mnt/arch/home/rocketmouse/Desktop# dmesg | grep TSC
[ 0.000000] Fast TSC calibration using PIT
[ 0.000000] Marking TSC unstable due to TSCs unsynchronized
root@debi386:/mnt/arch/home/rocketmouse/Desktop# grep TSC /var/log/messages
Jan 16 09:28:08 debi386 kernel: [ 0.000000] tsc: Fast TSC calibration using PIT
Jan 16 09:28:08 debi386 kernel: [ 0.000000] tsc: Marking TSC unstable due to TSCs
unsynchronized
Jan 16 09:28:08 debi386 kernel: [ 0.003000] calibrate_delay_direct() ignoring
timer_rate as we
had a TSC wrap around start=4287833042
>=post_end=13864416
Jan 16 09:50:58 debi386 kernel: [ 0.000000] tsc: Fast TSC calibration using PIT
Jan 16 09:50:58 debi386 kernel: [ 0.000000] tsc: Marking TSC unstable due to TSCs
unsynchronized
Jan 22 12:05:33 debi386 kernel: [ 0.000000] Fast TSC calibration using PIT
Jan 22 12:05:33 debi386 kernel: [ 0.000000] Marking TSC unstable due to TSCs
unsynchronized
Jan 22 are messages when booted to kernel 3.2.0-4-rt-686-pae i686 from
the repositories.
Jan 16 might be a broken kernel 3.8.13-rt14-pae-rocketmouse I build
based on a 3.8.13-rt14 x86_64 config.
E.g. Arch Linux 64-bit architecture
On startup I see "x86 Rt requires FEATURE_CONSTANT_TSC" or similar for
Arch Linux Rt kernels from the repositories and for the once I build.
This link for Chromebooks was the best explanation I found:
http://www.chromium.org/chromium-os/how-tos-and-troubleshooting/tsc-resynch…
root@debi386:/mnt/arch/home/rocketmouse/Desktop# grep tsc /proc/cpuinfo
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush mmx fxsr sse sse2 ht
syscall nx mmxext fxsr_opt rdtscp lm 3dnowext 3dnow
extd_apicid pni cx16 lahf_lm cmp_legacy svm extapic
cr8_legacy 3dnowprefetch lbrv
flags : [snip] tsc [snip]
2. Linux-Rt and IRQ allocation
==============================
All kernels I used in the last years for *buntu, Debian and Arch Linux
<= 3.8.13-rt14 (kernels > 3.8.13-rt14 don't work on my machine) give my
graphics it's own IRQ, the Debian kernel 3.2.0-4-rt-686-pae doesn't.
What options do I need to enable, so that it will allocate the graphics
it's own IRQ too, instead of sharing it with the RME card?
Regards,
Ralf
22 Jan
22 Jan
6:56 p.m.
Ralf Mardorf wrote:
All Rt kernels for all Linux distros I use seem to
have an issue
regarding to TSC.
kernel: tsc: Marking TSC unstable due to TSCs unsynchronized
This is a property of your CPU (whatever it is).
When multiple cores do not have exactly the same TSC time, it is not
possible to use this for timing in code that might be migrated to
another core.
2. Linux-Rt and IRQ allocation
==============================
All kernels I used in the last years for *buntu, Debian and Arch Linux
<= 3.8.13-rt14 (kernels > 3.8.13-rt14 don't work on my machine) give my
graphics it's own IRQ, the Debian kernel 3.2.0-4-rt-686-pae doesn't.
What is difference in /proc/interrupts?
Regards,
Clemens
27 Jan
27 Jan
6:25 p.m.
On Wed, 2014-01-22 at 18:56 +0100, Clemens Ladisch wrote:
Hi Clemens,
Im not absolutely sure if the 3.2 kernels already gave the graphics it's
own IRQ on my machine, when I used them a long time ago, but AFAIR those
kernels already did, at least the IRQ was displayed by commands that
should show the IRQ, but now something is fishy.
The graphics even isn't listed in /proc/interrupts for the Debian
3.2.0-4-rt-686-pae. Today I build a 3.8.13-rt14-pae kernel that is ok.
rocketmouse@debi386:~$ uname -a
Linux debi386 3.8.13-rt14-pae-rocketmouse-2 #1 SMP PREEMPT RT Mon Jan 27 15:47:47 CET 2014
i686 GNU/Linux
rocketmouse@debi386:~$ /etc/init.d/rtirq status
PID CLS RTPRIO NI PRI %CPU STAT COMMAND
39 FF 90 - 130 0.0 S irq/8-rtc0
644 FF 85 - 125 0.0 S irq/18-snd_hdsp
646 FF 80 - 120 0.0 S irq/20-snd_ice1
650 FF 79 - 119 0.0 S irq/21-snd_ice1
631 FF 75 - 115 0.0 S irq/19-ehci_hcd
632 FF 75 - 115 0.0 S irq/16-ohci_hcd
634 FF 74 - 114 0.5 S irq/17-ohci_hcd
649 FF 73 - 113 0.2 S irq/17-ohci_hcd
38 FF 70 - 110 0.0 S irq/1-i8042
27 FF 50 - 90 0.0 S irq/9-acpi
126 FF 50 - 90 0.6 S irq/22-ahci
569 FF 50 - 90 0.0 S irq/7-parport0
621 FF 50 - 90 0.0 S irq/22-firewire
623 FF 50 - 90 0.0 S irq/43-radeon
625 FF 50 - 90 0.0 S irq/14-pata_ati
626 FF 50 - 90 0.0 S irq/15-pata_ati
642 FF 50 - 90 0.0 S irq/18-ohci_hcd
651 FF 50 - 90 0.0 S irq/18-ohci_hcd
1883 FF 50 - 90 0.0 S irq/42-eth0
3 FF 1 - 41 0.1 S ksoftirqd/0
15 FF 1 - 41 0.2 S ksoftirqd/1
rocketmouse@debi386:~$ ls /proc/irq/* | grep radeon
radeon
rocketmouse@debi386:~$ ls /proc/irq/43 | grep radeon
radeon
rocketmouse@debi386:~$ sudo lshw -c video | grep irq
resources: irq:43 memory:d0000000-dfffffff memory:fdff0000-fdffffff ioport:ce00(size=256)
memory:fde00000-fdefffff
rocketmouse@debi386:~$ uname -a
Linux debi386 3.2.0-4-rt-686-pae #1 SMP PREEMPT RT Debian 3.2.51-1 i686 GNU/Linux
rocketmouse@debi386:~$ /etc/init.d/rtirq status
PID CLS RTPRIO NI PRI %CPU STAT COMMAND
36 FF 90 - 130 0.0 S irq/8-rtc0
623 FF 85 - 125 0.0 S irq/18-snd_hdsp
634 FF 80 - 120 0.0 S irq/20-snd_ice1
638 FF 79 - 119 0.0 S irq/21-snd_ice1
560 FF 75 - 115 0.0 S irq/19-ehci_hcd
569 FF 75 - 115 0.0 S irq/16-ohci_hcd
570 FF 74 - 114 0.0 S irq/17-ohci_hcd
586 FF 73 - 113 0.0 S irq/17-ohci_hcd
34 FF 70 - 110 0.0 S irq/1-i8042
24 FF 50 - 90 0.0 S irq/9-acpi
129 FF 50 - 90 0.3 S irq/22-ahci
561 FF 50 - 90 0.0 S irq/22-firewire
565 FF 50 - 90 0.0 S irq/14-pata_ati
566 FF 50 - 90 0.0 S irq/15-pata_ati
574 FF 50 - 90 0.0 S irq/18-ohci_hcd
593 FF 50 - 90 0.0 S irq/7-parport0
594 FF 50 - 90 0.0 S irq/18-ohci_hcd
1855 FF 50 - 90 0.0 S irq/42-eth0
3 FF 1 - 41 0.1 S ksoftirqd/0
13 FF 1 - 41 0.1 S ksoftirqd/1
rocketmouse@debi386:~$ ls /proc/irq/* | grep radeon
rocketmouse@debi386:~$ sudo lshw -c video | grep irq
resources: irq:18 memory:d0000000-dfffffff memory:fdff0000-fdffffff ioport:ce00(size=256)
memory:fde00000-fdefffff
Regards,
Ralf
2. Linux-Rt
and IRQ allocation
==============================
All kernels I used in the last years for *buntu, Debian and Arch Linux
<= 3.8.13-rt14 (kernels > 3.8.13-rt14 don't work on my machine) give my
graphics it's own IRQ, the Debian kernel 3.2.0-4-rt-686-pae doesn't.
What is difference in /proc/interrupts?
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days inactive
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2 comments
2 participants
participants (2)
-
Clemens Ladisch -
Ralf Mardorf