Unable to view LTTNG profile from ARM on Eclipse Trace - lttng

I have successfully cross compiled LTTng for arm and been able to do a quick test on the board. I performed LTTng sessions on a build machine and on the board. Was able to interpret both sessions using Babeltrace. That's fine. But on importing to Eclipse, only the session from the build machine was displayable. What gives? Is it not outputting in the same formats?
Few more information: under both session directories, there are channel.idx and metadata files. But only for the build session, Eclipse shows it as one icon, with CPU usage, LTTng Kernel Analysis, Tmf Statistics Analysis. For the board, it just lists the files.
Has any one met the same problem? Or were able to interpret an LTTng embedded session on Eclipse?

The Eclipse plugin (recently renamed to "Trace Compass") uses its own implementation of a Java CTF reader, it's quite possible for it to have discrepancies with Babeltrace. It also hasn't been tested a lot with ARM traces, so it can definitely be a bug in the parser.
If you could open a bug on the bug tracker, and attach the problematic trace, it would be extremely helpful!

Related

How to debug debugging using Clion -> armgdb -> J-link gdb server

I am trying to use Clion IDE to debug various NXP ARM M MCUs using J-link.
In case when program is only in RAM it works fine but but in case of flash targets after program load IDE often slows down for a while and then I will get timeout. Some click on pause button in right moment pauses program somewhere and allows me to debug...
My question is there any way how to see interactions of IDE with armgdb client or armgdb and j-link gdb server?
I tried to capture communication with gdb server using wire shark but it seems to be a binary protocol...
Thank you.
I found there is possibility to let gdb echo commands which showed me what is going on.
Unfortunately in case of Clion the only way is to put it into .gdbinit file in the root of project.
set trace-commands on
It showed me warning
warning: A handler for the OS ABI "Windows" is not built into this configuration
of GDB.
Which leads me to comment of this question gdb-multiarch (MINGW64) cannot determine architecture from executable?
Well I am not sure what caused Clion to hang but having .gdbinit with just set osabi none in it solved it.

Monitor process resources on Windows CE 5.0

I'm developing a WinCE 5.0 application that uses two commercial libraries. When the application starts calling the second library it gets slowlier and then after some use, it hangs and the whole OS freezes. It has to be rebooted to work again. The thing is that I'm developing this without a physical device (a testing person installs each release and runs the tests) and without an emulator (the device provider is not facilitating an OS image).
My intuition tells me that the second library is using all the available resources (basically, handles and memory) for a WinCE 5.0 process. I have to prove this to the library vendor. So I wish to add to my logs some general process and system information. Could you recommend me which APIs to call to get this information in CE?
I would really appreciate any hint
Thanks in advance!
Windows CE provides a very robust set of APIs for a subsystem called CeLog. CeLog is what Kernel Tracker uses to collect and display it's information. You can get all the way down to scheduler calls and thread migrations if you want. The real danger with using CeLog is in collecting too much data so that making sense of it is difficult, but if you filter the collections to just your process, that should help. You could collect the data to a log file, then use Kernel Tracker to open and view that data.
Here are some good starting points for info:
Introduction to Remote Kernel Tracker
More on Remote Kernel Tracker
CeLogFlush.exe (particularly the section 'Collecting Data on a Standalone Device with CeLogFlush')
Implementing a Custom Event Tracking Library
Embedded Visual C++ 4 contained "Remote Performance Monitor" that could do just that. Microsoft retracted EVC4 as free download some time ago, but it can still be downloaded from MSDN or found on the internet.
With service pack 4 it should work for WinCE 5.0. It does not appear to work with Windows Embedded 6.0 and newer though.

8051 serial debug monitors

I'm working with an 8051 (Cypress FX2LP) that doesn't have jtag/bdm capability. Typically, developers on this project have been using ad-hoc serial printfs for debugging. I'm looking into options for serial debug monitors such as Keil's Mon51, Isd51 or IAR's generic ROM-monitor.
I'll need to modify/configure this debug monitor to write to code RAM (to set software breakpoints). I'd guess that most 8051 debug monitors offer the ability for such modifications in order to support Harvard architecture or bank switching.
Does anybody have recommendations for serial debuggers for 8051 or similar processors?
Have you had to modify it to write to Harvard code RAM or flash etc?
I used for years Keil uVision PK51 and the Cypress FX2 EZ-USB Development kit. This kit (EZ-USB_devtools_version_261700.zip) worked correctly with FX2 and FX2LP.
It includes a Windows driver that automatically downloads the monitor firmware on board and stay resident in 8051 memory. This monitor takes control of one of the 2 serial board and manage the communication with the debugging tool. You have to set the Keil environment debugger to use the "Keil Monitor-51 driver".
Once your fw is downloaded and running you can set breakpoints, display watch, etc...
The Cypress driver works correctly with Windows 2K/XP. I never tried it with Vista or later. Probably there is a newer version of the Cypress that is able to run on the latest Windows.
Good luck
I have been using Mon51 with the Cypress FX2 for going on 10 years with very good success. In addition we use the RTXtiny task switcher and code banking. I have found the monitor to be generally solid and with enough functionality for our needs.
The Mon-51 code comes as a library from Keil, so it is not available. A couple of years ago I was having trouble getting code banking to work with the monitor, and since I wasn't getting very good support from Keil, I started to disassemble the monitor to figure out what was going wrong. Before I got very far I solved my problem and I never finished the reverse engineering project.
Our hardware platform is "von-neumanized" so that code and xdata space overlap. This is necessary for the monitor to work correctly. We have modified the monitor initialization code so that it runs at 115200 baud from an external uart and that works well. In addition we had to build our own version of the monitor so that it was located at a different location in memory. Keil has actually made it pretty easy to configure things without having to dive into the actual monitor code.

Low level qemu based debugging

I've to test some low level code on an ARM architecture. Typically experimentation is quite complicated on the real board, so I was thinking about QEMU.
What I'd like to get is some kind of debugging information like printfs or gdb. I know that this is simple with linux since it implements both the device driver for the QEMU Integrator and the gdb feature, but I'm not working with Linux. Also I suspect that extracting this kind of functionality from the Linux kernel source code would be complicated.
I'm searching from some simple operating system that already implements one of those features. Do you have some advice?
You don't need a target OS to debug code that's running inside QEMU -- QEMU already does that for you.
Specifically, QEMU supports remote debugging from GDB -- you can run QEMU with the appropriate command-line options and it will export an interface that a copy of GDB (running on the host machine) can connect to. At that point, you can debug the program in GDB pretty much just as if you were running it on the host machine.
http://wiki.osdev.org/GDB appears to have a bit more basic information; possibly not enough to completely get you started, but at least give you the basic idea and some terms to look for in the QEMU and GDB documentation. Skip over the bit about "Implementing GDB Stubs", which doesn't apply here since QEMU has one already, and start at the section on "Using Emulator Stubs". The short form is simply that you start QEMU with the -s option (export a GDB connection on localhost:1234) and the -S option (wait for a GDB "continue" command before starting execution), and then in GDB on your host you say target remote :1234 instead of run. Also, of course, you need to be using an ARM version of GDB rather than a native-x86 one.
(In addition, if you're willing to pay for a commercial solution, CodeSourcery's ARM toolchain has the IDE integration to set all of this up automatically, including support for "printf" to print into the debugger console. That works on a physical board, too, if you've got a hardware debugger. Usual disclaimer about me being a CodeSourcery employee applies -- but I do find it very easy to use.)
Update, 2012: CodeSourcery's toolchain is now called Mentor Graphics Sourcery CodeBench, but all the above still applies.
I realise that I am addressing your original problem here rather than your proposed solution (perhaps that's better?), but to use GDB (or Insight/GDB) directly on the target, use a low-cost JTAG tool and OpenOCD. An example of such a set-up and how to implement it can be found here.
If you have a larger budget, a more fully featured JTAG debugger may be useful, such as the Abatron BDI3000 with bdiGDB firmware which allows remote debugging and device programming over Ethernet with GDB and no special drivers or target debug agent.
Maybe a microkernel like OKL4 would suit your needs?

kvm vs. vmware for kernel debugging / USB driver development

I'm currently setting up vmware Server 2.0 for kernel debugging with gdb ( see this setup guide ) and someone asked me why not use kvm?
So I ask: kvm vs. vmware for kernel debugging / USB driver development
what are the pros and cons of each?
Driver development? are you working on a driver for a particular piece of hardware? if so, then you probably won't be able to use virtualization, because the virtualized instance won't have access to the new hardware.
For this you will need two machines, one running a remote debugger on the other.
*Edit: * Apparently you're developing a driver for a USB Device? this is one area in particular that a VM actually Can help. These days most VM's have the ability to delegate specific USB devices to a guest OS.
That said, this situation doesn't really offer any benefits over the remote debugger option, because you still need a way to inspect the state of the running or crashed OS, and VM's offer very little assistance in this regard. You might be able to replay saved states from just before a crash.
You might be able to get a bit of traction using UML, which would allow you to do local debugging as on a regular user process, which is a little bit less trouble.
Instead of answering the direct question I'll add another option... Depending on if the kernel in question is a Linux kernel, and what part(s) of it you are working on, you might find that UserModeLinux (included in the 2.6.x source, and available as patch sets for 2.4 and 2.2) may trump both of those options.
As it runs the kernel as a userland process under the host kernel it is easier to attach common debugging tools to. I believe it is very commonly used in the early stages of updates/additions to file-system related code. If you are developing/debugging modules that interact directly with hardware it may be much less use to you though.
Reference links: home,
other
I recently started building GNU Mach/HURD and found the combination of QEmu/KVM to work really quite well.. for the following reasons:
QEmu presents quite a clean environment
Networking has alot of options
I can easily mount the filesystem using a raw device file / loopback
Bottom line is, for kernel work I just want the minimum of functionality to boot and see the result. VMWare is much more for usable virtualization rather than down-and-dirty.
There is however no comparison to booting on a real machine with real hardware. The VM environment can seem like a safety blanket somtimes ... because even my toaster would know what a Realtek RTL8139C was.
If it is a "real hardware" device, of course, vmware will not emulate it, so you won't be able to debug the driver under it (nor will any other virtualisation software, unless you extend one to do so).
Device driver debugging can be done to some extent with a real hardware machine with a normal kernel - although there are obviously things you can't do - like set breakpoints.
It is still possible to attach a debugger to the kernel and inspect stuff. Moreover, traditional printf() debugging is quite possible (printk, anyone), and there are various features in the kernel which make debugging easier. It's possible to build the kernel with various debug options to try to detect pointer problems, memory leaks etc.
By default, the kernel even gives a nice-ish stack trace on the log when it encounters an OOPS or BUG condition (obviously this does not necessarily get written anywhere if the system hangs or crashes). Of course a pointer-out-of-range condition happening inside an interrupt is a recipe for disaster, but you could still get a stack trace on the screen immediately before the panic :)

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