[Rtai] Rtai Digest, Vol 131, Issue 12

Discussion:

Mohsen Alizadeh Noghani

2018-11-15 11:14:48 UTC

I'm curious, why would one need to use RTAI 5.1 with an i5 CPU?
Best,
Mohsen

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1. Re: ?TIMER_8254_IRQ? undeclared (Paolo Mantegazza)
----------------------------------------------------------------------
Message: 1
Date: Mon, 12 Nov 2018 21:19:26 +0000
Subject: Re: [Rtai] ?TIMER_8254_IRQ? undeclared
Content-Type: text/plain; charset="Windows-1252"
I do not know why you need the 8254 timer but, since you have a TSC in your cpu flags, RTAI does not need an 8254 for sure.
Thus, in relation to RTAI, you have just to compile your kernel with an INTEL CORE CPU, to be selected under "Processer type and features -> Processor family".
Moreover, since you have an I5 Core, you should use RTAI-5.1.
Paolo
________________________________________
Paolo,
Here is my cpu info
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Byte Order: Little Endian
CPU(s): 4
On-line CPU(s) list: 0-3
Thread(s) per core: 1
Core(s) per socket: 4
Socket(s): 1
NUMA node(s): 1
Vendor ID: GenuineIntel
CPU family: 6
Model: 158
Stepping: 9
CPU MHz: 3408.009
BogoMIPS: 6816.01
Virtualization: VT-x
L1d cache: 32K
L1i cache: 32K
L2 cache: 256K
L3 cache: 6144K
NUMA node0 CPU(s): 0-3
Flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 fma cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch ida arat epb pln pts dtherm hwp hwp_noitfy hwp_act_window hwp_epp intel_pt tpr_shadow vnmi flexpriority ept vpid fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm mpx rdseed adx smap clflushopt xsaveopt xsavec xgetbv1
when I was configuring my kernel to compile my slected cpu was generic-x86_64 as architecture.
________________________________________
Sent: Monday, November 12, 2018 1:36 PM
Subject: [Rtai] ?TIMER_8254_IRQ? undeclared
Dear all,
I am trying to update a rtai system currently running with RTAI 3.9 to RTAI 5.0.1. When I compile my system I am getting the error "?TIMER_8254_IRQ? undeclared". At first I thought it was a library inclusion error, so I double checked the libraries included between my version using RTAI 3.9 and my version using RTAi 5.0.1 and there is no library missing at first. I'd like to know if this "TIMER_8254_IRQ" is no longer supported on RTAI, and if this is the case how should I proceed to update my calls to that or, if this macro still exists, how can I make my system recognize this macro with RTAi 5.0.1?
I am also letting my compiling log for this particular system, osLx26 is my kernel module main file.
make -C /lib/modules/4.1.18-rtai/build SUBDIRS=/home/gmtbro/repos/samplus/rtcore modules
make[1]: Entering directory `/usr/src/kernels/4.1.18-rtai'
CC [M] /home/gmtbro/repos/samplus/rtcore/osLx26.o
/home/gmtbro/repos/samplus/rtcore/osLx26.c:257:24: error: ?TIMER_8254_IRQ? undeclared (first use in this function)
rt_assign_irq_to_cpu(TIMER_8254_IRQ, TIMER_TO_CPU);
^
/home/gmtbro/repos/samplus/rtcore/osLx26.c:257:24: note: each undeclared identifier is reported only once for each function it appears in
make[2]: *** [/home/gmtbro/repos/samplus/rtcore/osLx26.o] Error 1
make[1]: *** [_module_/home/gmtbro/repos/samplus/rtcore] Error 2
make[1]: Leaving directory `/usr/src/kernels/4.1.18-rtai'
If I just remove the rt_assign_irq_to_cpu function call the compiller starts to return errors in the kmalloc definition at linux/slab.h, so another question would be: is this error somehow related to the TIMER_8254_IRQ macro?
Thanks in advance,
Victor Costa
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End of Rtai Digest, Vol 131, Issue 12
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Paolo Mantegazza

2018-11-15 11:27:40 UTC

Permalink

Because with I5 and onward CPUs the tricky, likely more efficient, way
with which RTAI recovers user space data placed on stack does not work
anymore. The old way remains but must be set when RTAi is configured.
P.

Post by Mohsen Alizadeh Noghani
I'm curious, why would one need to use RTAI 5.1 with an i5 CPU?
Best,
Mohsen

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Paolo Mantegazza

2018-11-15 11:51:36 UTC

Permalink

In relation to my answers suggeting the use of RTAI-5.1 with INTEL CPUS
versions >= I5, I've to correct myself.
In fact, with reference to a version IX-Y, what counts is not the IX
term but the Y one as, if I remember it well, RTAI versions below 5.1
will not work for Y > 5xxx.
Sorry for the confusion.

Paolo

Post by Mohsen Alizadeh Noghani
I'm curious, why would one need to use RTAI 5.1 with an i5 CPU?
Best,
Mohsen

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Alec Ari

2018-11-15 20:17:32 UTC

Permalink

I have not heard of any i5s or i7 users have any issues running my code from my forked RTAI tree.. What problems are you having with older releases, Paolo?

Alec

Paolo Mantegazza

2018-11-16 10:10:09 UTC

Permalink

As I said in a following message, the problem is not with the I
versions. Thus, for an INTEL Ix-yzzz, RTAI versions older than 5.1 will
not work for y > 5.

The fix in 5.1 has not been ported backward.

It all started with the following email excerpt:
----------------------------------------------------------------------------------------------------------------------------------

[Rtai] sched: problem with paging request on linux 3.16
Rtai [rtai-***@rtai.org] on behalf of PAUL-SOFTWARE [***@paul.eu]
Sent: Wednesday, May 3, 2017 1:53 PM
To:
***@rtai.org
Attachments:
ATT00001.txt‎ (442 B‎)
Hello,

I installed rtai-5.0-test2 on Debian Jessie with 32Bit kernel 3.16.7, using the hal-patch from magma (hal-linux-3.16.7-x86-5x.patch).

Everything works fine on a board with Intel i3-4130 CPU.
On a system with Intel i3-6110 CPU I get an error when I insert rtai_sched.ko.
----------------------------------------------------------------------------------------------------------------------------------

It is possible that it was signaled before but, since I had not a
hardware to work with for a fix, it was Josef the one that helped me by
running on his troubled i3-6110 a series of diagnose tests I sent him.

Paolo.

Post by Alec Ari
I have not heard of any i5s or i7 users have any issues running my code from my forked RTAI tree.. What problems are you having with older releases, Paolo?
Alec