- l4-hackers - example.com Site

Facing l4x-evict_task problem in L4Linux
by Irvanda Kurniadi 10 May '14

10 May '14

Hi hackers, I want to ask you about my problem in running mpi-program over L4Linux. I'm usinng ubuntu 12.04 kernel with gnu libc-2.15. I put the library from /lib/i386-linux-gnu/ to /lib in my custom ramdisk. Then I put the library that is compiled in the kernel's host to the /usr/lib in my custom ramdisk. I also put my mpi hello program and my own mpi program which are compiled in the kernel's host (I mean in ubuntu 12.04 with libc-2.15). I'm using MPICH3 for the mpi library and I use gforker process manager. When I run the mpi Hello program, it can run properly (I invoke "mpiexec -n 4 ./mpi_hello and there are 4 output from different 4 different processor, it means the program run properly). Then I run my own mpi application which also include the tiff, jpeg, amd libstep libraries that I put altogether in /usr/lib/ in my custom ramdisk. But I got this error message when I invoke "mpiexec -n 1 ./mpi_program image.tif" or "mpiexec -n 2 ./mpi_program image.tif" command (shown below). l4x-evict_tasks: 1089 callbacks suppressed l4x-evict: Found no process to free l4x-evict: Found no process to free l4x-evict: Found no process to free INFO: rcu_sched detected stalls on CPUs/tasks: { 1} (detected by 0, t=348877 jiffies, g=4294967184, c=4294967183, q=(5) sending NMI to all cpus: and I can't interrupt the running process. I presume this problem happens because the all of process have been finalized but the l4linux kernel still think that there is a remaining process that should be freed. But I'm not sure about this. If you know about this, plis let me know how to fix it and if you can give me an explanation about this I will be really grateful. Thanks, Irvanda

2 1

Re: How to talk to a specific thread in a server
by Björn Döbel 09 May '14

09 May '14

Could you share your client and server's code? Bjoern Am 08.05.2014 21:02, schrieb Yuxin Ren: > Year, > I did those thing. Each server tread has its own server obj and register > server instance, and it calls register_obj() and server.loop() on their own. > But this does not work. And actually the master thread in server always > receives all requests. When I let the master thread to spin, the server > cannot > receive any request, even though other threads in server block on the > server.loop() function. > I am really confused about it. > > Thank you. > > > On Thu, May 8, 2014 at 12:22 PM, Björn Döbel <doebel(a)os.inf.tu-dresden.de>wrote: > > Am Do 08 Mai 2014 18:17:54 CEST schrieb Yuxin Ren: >>>> HiThank you very much for your reply.I did what you said, but the > behavior is very confusing.I create two channels in lua script, and > correspond each channel to a pair of client and server threads. >>>> In the server side, each thread registers its own server obj to its > own Registry_server, and of course they have different dispatch > functions.Now the result is only one server thread receive all requests > from client, and it selects different dispatch function to run based on the > request. >>>> But I want different threads to run different dispatch function, not > only one server thread process all requests using different dispatch > functions.Do you have any ideas about this?Thank you. >>>> On Thu, May 8, 2014 at 2:07 AM, Björn Döbel <doebel(a)os.inf.tu-dresden.de> > wrote: >>>> >>>> ********* *ANFANG des verschlüsselten oder unterschriebenen Bereichs* > ********* >>>> >>>> Hi, >>>> >>>> On 08.05.2014 03:29, Yuxin Ren wrote: >>>>> I have one client and one server talking to each other, and both of >>>>> them have 2 threads. I want thread 1 in client only talk to thread >>>>> 1 in server, and thread 2 in client only talk to thread 2 in >>>>> server. How can I achieve this? >>>> >>>> The simple client/server example >>>> (http://wiki.tudos.org/L4Re_simple_client_server_example) shows how to >>>> connect a single thread in each process (or task in L4 speak). You >>>> could extend this example to create two channels in the Lua setup >>>> file, pass both channels to the tasks during startup and then let each >>>> thread use one of them for communication with its counterpart. >>>> >>>> Note that does not completely enforce your requirement that each >>>> thread can only talk to exactly one other. Capabilities (e.g., for the >>>> communication channels) are shared per task and technically each >>>> thread could therefore send messages on each channel. If you want >>>> strict isolation, you have to separate the threads into separate tasks. >>>> >>>> Bjoern >>>> >>>> >>>> ********* *ENDE des verschlüsselten oder unterschriebenen Bereichs* > ********* >>>> >>>> _______________________________________________ >>>> l4-hackers mailing list >>>> l4-hackers(a)os.inf.tu-dresden.de >>>> http://os.inf.tu-dresden.de/mailman/listinfo/l4-hackers >>>> >>>> >>>> >>>> > > Quick guess: your separate threads need to call the register_obj() > function and the server.loop() functions on their own. (You also need > two independent instances of the Server_object.) > > Bjoern >> >> >

2 1

How to talk to a specific thread in a server
by Yuxin Ren 08 May '14

08 May '14

I have one client and one server talking to each other, and both of them have 2 threads. I want thread 1 in client only talk to thread 1 in server, and thread 2 in client only talk to thread 2 in server. How can I achieve this? Thanks

2 3

Compile library in L4Linux ramdisk
by Irvanda Kurniadi 07 May '14

07 May '14

Hi hackers, Can you help me to check whether my understanding about library in L4Linux is right or wrong? IMO, the library in L4linux ramdisk should be compiled with the same version of compiler. But I found out that every application in l4linux ramdisk is compiled by glibc 2.2.5 for GNU/Linux 2.0.30 which is very old version. Does it mean I have to build the library over that system and then put the built library to the ramdisk of l4linux? Thanks, Irvanda

2 1

What is 'new-res Mmio_ram(0x80000, 0 )' in '.io' file ?
by Taeung 07 May '14

07 May '14

Hi, l4 hackers :-) I'm trying to secure Ethernet on L4 linux using Freescale imx6q. Referencing other 'imx28.io' file which succeeded in securing Ethernet , I'm modifying my 'imx6q.io' file as follows.. =================== hw-root { NIC => new Deviceo() { .hi-d = "imx6q-fec"; new-res Mmio (0x02188000 .. 0x0218BFFF); new-res Irq (150); new-res Irq (151); } DMAMEM => new Deivce() { .hid ="dmamem"; new-res Mmio_ram (0x80000, 0); } 141x => new System_bus() { "imx6q-fec" -> wrap(hw-root.NIC); "dmamem" => wrap(hw-root, DMAMEM); ) } =================== What mean 'DMAMEM' ? And What is the function of which name is 'Mmio_ram()' ? I know that 'Mmio()' need arguments which are start and end address. But, I don't know 'Mmio_ram()'. Please, help me. If you tell a bit me hints, I'd appreciate it. - Taeung -

2 1

How to enable 'CONFIG_COMMON_CLK' ?
by Taeung 30 Apr '14

30 Apr '14

Hello, L4 Hackers :-) I'm trying to build L4 Linux with added option of MMC device driver. When I've tried to compile L4 Linux , I've failed it with error log such as.. ============== drivers/built-in.o: In function `sdhci_pltfm_clk_get_max_clock': /home/taeung/test/source/l4linux/drivers/mmc/host/sdhci-pltfm.c:43: undefined reference to `clk_get_rate' make[1]: *** [vmlinux] Error 1 make: *** [sub-make] Error 2 ============== After I saw the log , I've guessed the cause is that 'drivers/clk/clk.c' was not built. So, I must enable 'CONFIG_COMMON_CLK' , to build 'drivers/clk/clk.c' How to enable 'CONFIG_COMMON_CLK' ? For reference, I've tried to compile L4 Linux with options as follows.. =================================== --- MMC/SD/SDIO card support [ ] MMC debugging [*] Assume MMC/SD cards are non-removable (DANGEROUS) [ ] MMC host clock gating *** MMC/SD/SDIO Card Drivers *** <*> MMC block device driver (8) Number of minors per block device [*] Use bounce buffer for simple hosts < > SDIO UART/GPS class support < > MMC host test driver *** MMC/SD/SDIO Host Controller Drivers *** < > ARM AMBA Multimedia Card Interface support -*- Secure Digital Host Controller Interface support -*- SDHCI platform and OF driver helper <*> Marvell MMP2 SD Host Controller support (PXAV3) < > Marvell PXA9XX SD Host Controller support (PXAV2) < > Synopsys DesignWare Memory Card Interface ==================================== -Taeung -

2 2

L4Linux on amd64 arch
by Irvanda Kurniadi 28 Apr '14

28 Apr '14

Hi hackers, Is there anyone who has tried to build l4linux on amd64? I compiled the new snapshot of L4re, but there is no l4linux for amd64. Can I barely compile this l4linux in l4re-amd64? thanks, Irvanda

2 3

L4linux: cpu and core [comprehension question]
by Irvanda Kurniadi 27 Apr '14

27 Apr '14

Hi hackers, I am a little bit confused about the term of cpu and core in l4linux. I have a system with 8 processor intel xeon E5606 with 4 cores in each cpu. I'm going to maximize it to become the maximum number of cores in all cpus. But I am confused in determining the l4x_cpus that what is the term cpu in here? Is it literally cpu or the number of threads that can be handled in each core? I run an openmp hello world apps over l4linux. I call the omp_get_thread_num() and I got 4 threads in the result. Are these 4 threads obtained from 4 cores in single cpu? So, if I'm right, how can I optimize to use all of the cpu existed in the system? I've tried to use l4x_cpus=8 and l4x_cpus=32, but those commands doesn't work for me. In my opinion, if I can maximize until the maximum number of cores and I have 32 threads that run concurrently, then it will be served by each core in those 8 cpus. In fiasco configuration, there is maximal supported number of CPUs. So referring to my case, the maximum is supposed to be 8, am I right? In case of thread migration in example ex_thread_migrate, I create 16 threads and will be migrated to each cpu. Here is the result: migrate | Migrated Thread00 -> CPU02 migrate | Migrated Thread01 -> CPU03 migrate | Migrated Thread02 -> CPU04 migrate | Migrated Thread03 -> CPU05 migrate | Migrated Thread04 -> CPU06 migrate | Migrated Thread05 -> CPU07 migrate | Migrated Thread06 -> CPU00 migrate | Migrated Thread07 -> CPU01 migrate | Migrated Thread08 -> CPU02 migrate | Migrated Thread09 -> CPU03 migrate | Migrated Thread10 -> CPU04 migrate | Migrated Thread11 -> CPU05 migrate | Migrated Thread12 -> CPU06 migrate | Migrated Thread13 -> CPU07 migrate | Migrated Thread14 -> CPU00 migrate | Migrated Thread15 -> CPU01 My question is do the thread00 and thread08 share the same core in CPU02 or they use different core in CPU02 which run concurrently? And also, is it normal to get the output like cpu[1] to cpu[7] goes to idle loop? Thanks, Irvanda

2 3

Re: L4Linux and L4Re communication
by Björn Döbel 25 Apr '14

25 Apr '14

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 25.04.2014 10:24, Irvanda Kurniadi wrote: > On Fri, Apr 25, 2014 at 4:24 PM, Björn Döbel > <doebel(a)os.inf.tu-dresden.de <mailto:doebel@os.inf.tu-dresden.de>> > wrote: > > -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 > > Hi, > >> In term of running hello world in L4Linux, I can run it by >> passing -m32 -static in the compilation process. But, now I'm >> having a problem in running the mpi-based application on L4Linux >> which this apps needs the mpi library to be able to run. I have >> ported the mpi library and run the apps over L4Re by using Ned. >> So, based on the explanation above, I don't understand how to run >> the mpi-based program on top L4Linux in which the L4Linux >> definitely doesn't have mpi-library because the mpi-library is >> existed in L4Re. Is it like this, the l4linux kernel needs the >> device driver to communicate with external L4 apps (in my case >> mpi-base apps), then to trigger the communication we should make >> the kernel module (linux program to talk to the l4linux kernel). >> Am I right? Can you point one example, which is similar with my >> case, that can be followed by me? > > I see two different scenarios here: > > > 1. Your MPI application is supposed to run as a Linux application > in L4Linux - -> In this case all you need is an MPI library > installed in the Linux distribution that you boot L4Linux into. > E.g., if you are using some custom ramdisk, simply add a (Linux) > MPI library to this disk and your program will then use it. No L4 > magic necessary at all. > > > 2. Your MPI application is supposed to run directly on L4Re - -> In > this case you don't need any Linux or L4Linux in the setup. You > build your L4Re program and link it with your ported MPI library > and then it should run. > > Does that answer your question or am I missing your point? > > > Yes it does. In my case I think I only need to run my application > on L4linux, but since the beginning I misunderstood that I have to > port the library on L4. I have wasted so much time in doing > scenario 2. Sorry to hear that. > What is the differences between running application over L4linux > and running application as a task in L4Re? Good question. Let me try to explain from bottom up. 1. It all starts with Fiasco.OC, our microkernel. Fiasco runs directly on the hardware in the CPU's privileged mode. It provides kernel mechanisms, such as threads, tasks, inter-process communication and scheduling. - - - - - - - - - - - - - - - - - - - - - - - - - - - - +-------------+ Privileged CPU Mode | Fiasco.OC | +-------------+ 2. On top of Fiasco.OC we have the L4 Runtime Environment. L4Re is a set of libraries and applications that run in non-privileged (aka "user") mode and implement basic operating system services, such as memory management, device drivers etc. +------------------------+ | L4 Runtime Environment | Non-privileged +------------------------+ CPU mode - - - - - - - - - - - - - - - - - - - - - - - - - - - - +-------------+ Privileged CPU Mode | Fiasco.OC | +-------------+ 3. On top of L4Re you are free to implement your own software using L4Re's and Fiasco's primitives. This is where scenario #2 (MPI on L4Re) comes in. +-----------------+ +---------------------+ | MPI Application | | Another Application | +-----------------+ +---------------------+ +------------------------+ | L4 Runtime Environment | Non-privileged +------------------------+ CPU mode - - - - - - - - - - - - - - - - - - - - - - - - - - - +-------------+ Privileged CPU Mode | Fiasco.OC | +-------------+ In contrast to Linux this is a completely different operating system. You mostly don't see that because L4Re provides you with interfaces that are similar to Linux (e.g., a POSIX C library, a virtual file system etc.). With respect to MPI the difference here is that you have to adapt any kind of load balancing, process distribution etc. to use the respective Fiasco and L4Re services. 4. Now we have a special usage scenario: We can slightly adapt the Linux kernel and run it as an application on top of L4Re. This is called L4Linux and the approach is what we call virtualization. +----------------+ | L4Linux Kernel | +----------------+ +------------------------+ | L4 Runtime Environment | Non-privileged +------------------------+ CPU mode - - - - - - - - - - - - - - - - - - - - - - - - - - - +-------------+ Privileged CPU Mode | Fiasco.OC | +-------------+ 5. A single (L4)Linux kernel does not help you very much, because you want to run applications on top of Linux. Here the virtualization magic steps in and as a result you can run standard Linux applications on top of L4Linux without the need for any modification. Technically, these applications are L4 applications with the difference that their system calls are not sent to the Fiasco kernel but to the L4Linux kernel. The combination of the L4Linux kernel and all Linux applications running on top of it is what we call a virtual machine (VM). Linux VM .............................. . +-------------------+ . . | Linux Application | . . +-------------------+ . . +----------------+ . . | L4Linux Kernel | . . +----------------+ . .............................. +------------------------+ | L4 Runtime Environment | Non-privileged +------------------------+ CPU mode - - - - - - - - - - - - - - - - - - - - - - - - - - - +-------------+ Privileged CPU Mode | Fiasco.OC | +-------------+ This setup is how scenario #1 works. Your Linux MPI application believes it is running on a real Linux kernel and Fiasco's virtualization makes sure that everything works as expected. Kind regards, Bjoern -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 Comment: Using GnuPG with Icedove - http://www.enigmail.net/ iEYEARECAAYFAlNaJo8ACgkQP5ijxgQLUNmSfgCgkQUPRGJ/Vyq0DIQkEi/Dm9+2 gAcAnRdS9hHkIIp9qBYCfHHL1+Uuy2Fi =zFBP -----END PGP SIGNATURE-----

1 0

L4Linux and L4Re communication
by Irvanda Kurniadi 25 Apr '14

25 Apr '14

Hi, This thread is just a sequel from http://os.inf.tu-dresden.de/pipermail/l4-hackers/2013/006108.html > > Is it possible to run my application on top l4linux; like, > > if I want to run hello world application over l4linux (not just > > booting it over l4/fiasco)? I tried to run it by using this > > configuration: > > > > -- Start Hello loader:start( { caps = {}, l4re_bdg = L4.Dbg.Warn, > > log = {"hello","red"}, }, "rom/hello"); > > > > -- Start Linux loader:start( { caps = { log = L4.Env.log:m("rws"), > > fb = mag_svc:create(L4.Proto.Goos, "g=640x480"); vbus = > > vbus_l4linux; }, l4re_dbg = L4.Dbg.Warn, log = { "l4linux", > > "yellow" }, }, "rom/" .. lxname .. " mem=64M console=tty0 > > l4x_rd=rom/ramdisk-" .. L4.Info.arch() .. ".rd root=1:0 > > ramdisk_size=4000 init=linuxrc"); > > > > But I think it only run two different applications over l4/fiasco. > > > > Do you have any idea how to run the hello application over > > l4linux? > Bjoern said: > > The idea behind L4Linux is to run native Linux applications, so hello > world in L4Linux works just as the version you would write in your > local Linux. > > Running an application that communicates with both L4 and Linux is a > bit more involved. L4Linux applications don't talk to L4 apps > directly. The L4Linux kernel is an L4 app though, so it can do this > talking for you. The missing link then is to write a Linux device > driver that allows your Linux program to talk to the L4Linux kernel, > which then in turn communicates with an external L4 application. > > In term of running hello world in L4Linux, I can run it by passing -m32 -static in the compilation process. But, now I'm having a problem in running the mpi-based application on L4Linux which this apps needs the mpi library to be able to run. I have ported the mpi library and run the apps over L4Re by using Ned. So, based on the explanation above, I don't understand how to run the mpi-based program on top L4Linux in which the L4Linux definitely doesn't have mpi-library because the mpi-library is existed in L4Re. Is it like this, the l4linux kernel needs the device driver to communicate with external L4 apps (in my case mpi-base apps), then to trigger the communication we should make the kernel module (linux program to talk to the l4linux kernel). Am I right? Can you point one example, which is similar with my case, that can be followed by me? Thanks, Irvanda

2 2