Il 01/07/21 08:38, Jan Kiszka ha scritto:
On 28.06.21 16:33, Mauro S. via Xenomai wrote:
Hi all,
I'm using Xenomai3 (master branch, commit
d98c99798836dd3571144203b51ff787d2108f1b) on a X86_64bit Intel Atom
x5-E8000 with 2GB RAM, using kernel from Xenomai repos, in Cobalt
coniguration.
Just for completeness, I'm using a Yocto built filesystem (but I think
it doesn't matter to the issue that I'm going to describe).
Consider the simple test program attached: it creates 120 tasks that
does nothing than sleep. This test is compiled with the Yocto toolchain
using the attached makefile. Toolchain have Xenomai installed in.
(By the way, I needed to raise to 2048 the registry slots number in
kernel configuration: without raising this, I cannot create more than
110 tasks.)
If I kill this program with TERM signal, sighandler does its work and
the application exits cleanly.
If I kill this application with SEGV signal (no custom sighandler
installed), system freezes.
If I build this application with 50 tasks, then SEGV does not cause
system to freeze.
Bisecting the number of tasks, SIGSEGV freezes starts with a number of
tasks greater than 85.
I enabled watchdog (and almost all of the debug options) in Xenomai
section of the kernel configuration, without success.
Are there some system limits? I checked under /proc/xenomai but all
seems to be OK.
Thanks in advance, regards
Just reproduced over ipipe-core-5.4.124-x86-5: We are running into [1].
That is an architectural limitation of I-pipe that bit me a couple of
times in the past as well. You can shift that limit by increasing
WORKBUF_SIZE [2]. For you test case, using 4K was enough to get over the
hill. This is rather unhandy, no question.
The good news is: Dovetail with kernel 5.10+ is not affected by this
limitation anymore.
Jan
[1]
https://source.denx.de/Xenomai/ipipe-x86/-/blob/ipipe-x86-5.4.y/kernel/ipipe/core.c#L2030
[2]
https://source.denx.de/Xenomai/ipipe-x86/-/blob/ipipe-x86-5.4.y/kernel/ipipe/core.c#L74
Hi Jan,
thank you very much for your fast answer and for the patch.
Is there a upper limit on WORKBUF_SIZE value to consider?
Thanks again, regards
--
Mauro S.
