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RT issues
by Rene Wittmann 02 May '05

02 May '05

Hi, As I'm trying to implement a real-time application in DROPS, I still have some questions on this topic. Maybe there's someone who can answer them because I didn't find it described it the documentation... 1. The timer granularity seems to be set to 976 microsec. Is there a special background for using this number or can I set it down (maybe even to 10 microsec, which what be a good time resolution for my task)? How can I set it? Or would it be stupid to set it to such a tiny value? 2. When looking at the rt_sched example in the hello-package: the main-thread has a preempter-thread for recognizing timeslice overrun and deadline misses. When does this preempter-thread recognize a TS overrun or a deadline miss? Right after this event (so within the next time resolution) or after the main-thread says that is has finished it's work (meaning after a call to "l4_rt_next_reservation")? 3. How can the preempter-thread tell the main-thread to stop it's work in case of a timeslice overrun or even a deadline miss? 4. Does the system allow a thread's scheduling like this: period-length = 976 microsec, timeslice_mand = 9760 microsec, timeslice_opt = 9760 microsec (which would mean that the system had to reserve timeslices that don't fit into one period...) OR period-length = 9760 microsec, timeslice_mand = 4380 microsec, timeslice_opt = 4380 microsec (which would mean that the system had to reserve all resources for this thread..) (what would happen if another thread comes with a period_length of also 9760 microsec and a timeslice_mand = 6000 microsec? What would be the system's behaviour?) ===================================================================== Other thing: File system support: 1. which filesystems are supported (reiserfs?)? 2. Is there a way to have RT access to disk and accessing files this way? If so, how? Thanks, Rene

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L4 IPC doubt
by Tiago Jorge 02 May '05

02 May '05

hello to you all. Let me describe my cenario... I have my L4 server that receives ipc calls. The code was generated from DICE. And i have a lib and i've implemented a client that uses that lib. My L4 server also uses ipc to comunicate with other servers, mainly with flips that also uses IPC. that problem is the following: My client makes an IPC call and blocks waiting for the answer from my server... while processing that answer, my server has to comunicate with flips using IPC. The problem is here... my server blocks in the ipc_send when calling flips, but when i remove the call from the client it works fine, meaning that the client is not blocked waiting for ipc to return. My questions are... why can't i do IPC while another one that has nothing to do with my server is blocked? there can be only one ipc call in the whole system at a time? they all must be sequential? thanks in advance Tiago

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L4linux kernel module and IPC problem
by Leon Brits 29 Apr '05

29 Apr '05

Hi all, I've created some test code in a L4 Task, L4Linux App and L4Linux Kernel (2.4.28) module that communicates using short IPC messages. It works fine except that it seems that I can not send an IPC message to the L4Linux App from the Kernel Module (reverse is fine). l4_ipc_send() does not report any errors, but the App does not receive anything and the register values contains some 'random' values. Any suggestions for the reason? Suggestions as to how to debug this problem is appreciated! Thanks Leon

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boot : C++ App on fiasco kernel.
by 노학종 13 Apr '05

13 Apr '05

Hi, hackers. I downloaded the latest cvs version that is everything all including fiasco, l4env, libstdc++, ostkit, ostkit10... etc. And I completed compile all without some package where /l4/pkg/... (l4vfs, nethub, proxygon, verner) I tested a sample binary that is hello_cxx where in /l4/bin/x86_585 directory. My grub menu(menu.lst) contains: title Test_fiasco_kernel kernel /boot/fiasco/rmgr -sigma0 modadder 0x02000000 module /boot/fiasco/main -noserial -nowait -nokdb module /boot/fiasco/sigma0 module /boot/fiasco/hello_cxx following, boot error messages: *hello : [5.0] l4rm/lib/src/config.c : 104 : l4rm_get_dsm(); *hello : l4RM:no dataspace manager found!! In /l4/pkg/hello_cxx/README, you recommend that use Symbols, buffermgr, simple_dm binary into menu.lst to using C++ code together with L4 environment. But I can't find out that binary files. So I tested using above menu.lst. 1) Could somebody help me about problems above? *************************************** General questions; 2) I want to that My APP Program(e.g. sample_cxx) build using C++ is execute on the fiasco kernel only without L4linux(kernel) Is it enable? 3) If enable, Please somebody give me a instrucion to build, and a sample grub's menu.lst to execute a sample_cxx after booting with fiasco kernel, in lastest cvs version. Noh, H.J.

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Re: FLIPS issue
by Tiago Jorge 12 Apr '05

12 Apr '05

Christian Helmuth wrote: >Hello, > >it's me again. Could you please send me all source files for client and >server code under Linux as attachment with working broadcast code? So I >may get a chance to test it. > >Cheers > hello... sorry i'm bothering you again. first issue: i've been "investigating" the code and following the calls that all procedures do during their execution. And i cannot find where setsockopt in l4vfs is implemented :(. I don't see anyware the method l4vfs_net_io_setsockopt_component(...) implemented. Just its template. second issue: i've managed to get a serial cable to redirect output to another terminal, and i saw something i thought i saw earlier but didn't managed to figured it out. During flips boot it gives a strange error that i can't figure it out... ########################################################## flips-0 | l4dde_mm_init(): Using ... *flips-0 | 640 kB at 0x00280000 (vmem) *flips-0 | 1024 kB in 1 regions (kmem) *flips-0 | Initializing RT netlink socket *flips-0 | lo: I'm up now. *flips-0 | [9.2] ../../include/__macros.h:57:DICE_ERR(): *flips-0 | Error: call failed (ret -8 "item not found", exc 0) --- maybe this i *flips-0 : s okay for you! *flips-0 | Linux Tulip driver version 0.9.15-pre12 (Aug 9, 2002) *flips-0 | tulip0: MII transceiver #1 config 1000 status 786d advertising 05e1. *flips-0 | eth0: ADMtek Comet rev 17 at 0x1800, 00:30:05:62:64:4D, IRQ 11. *flips-0 | NET4: Linux TCP/IP 1.0 for NET4.0 *flips-0 | IP Protocols: ICMP, UDP, TCP *flips-0 | IP: routing cache hash table of 128 buckets, 3Kbytes *flips-0 | si_meminfo(): called (1) *flips-0 | TCP: Hash tables configured (established 128 bind 170) *flips-0 | CORBA_alloc(): size=1024, 1 pointers used *flips-0 | CORBA_alloc(): got block at 0x00180004 *flips-0 | CORBA_alloc(): size=1024, 2 pointers used *flips-0 | CORBA_alloc(): got block *flips-0 | flips_session_thread(): Flips(session_thread): new thread_id 9.8 *flips-0 | *flips-0 | CORBA_alloc(): size=1024, 3 pointers used *flips-0 | CORBA_alloc(): got block at 0x00180814 *flips-0 | CORBA_alloc(): size=1024, 4 pointers used *flips-0 | CORBA_alloc(): got block at 0x00180c1c *minifcfg| print_flags(): FLAGS for eth0: BROADCAST MULTICAST *minifcfg| print_flags(): FLAGS for eth0: UP BROADCAST RUNNING MULTICAST *minifcfg| print_flags(): FLAGS for eth0: BROADCAST MULTICAST *minifcfg| print_flags(): FLAGS for eth0: UP BROADCAST RUNNING MULTICAST *minifcfg| ifconfig(): eth0: inet 10.10.5.197 *minifcfg| *minifcfg| print_flags(): FLAGS for eth0: BROADCAST *minifcfg| ifconfig(): eth0: netmask 255.255.0.0 *minifcfg| main(): register at names *minifcfg| main(): eternal sleep *flips-0 | flips_session_thread(): Flips(session_thread): new thread_id 9.a *flips-0 | *flips-0 | CORBA_alloc(): size=1024, 5 pointers used *flips-0 | CORBA_alloc(): got block at 0x00181024 *flips-0 | CORBA_alloc(): size=1024, 6 pointers used *flips-0 | CORBA_alloc(): got block at 0x0018142c *testebro| main(): socket send error *testebro| main(): size_sent = -1 *testebro| *flips-0 | eth0: Setting full-duplex based on MII#1 link partner capability of 4 *flips-0 : 1e1. ################################################### *flips-0 | Error: call failed (ret -8 "item not found", exc 0) --- maybe this i *flips-0 : s okay for you! I don't know what this means, but my menu.lst looks like this... is it something missing? ########################################################### title Testes root (hd0,0) kernel /home/tiago/fiasco_builddir/rmgr -sigma0 modaddr 0x02000000 module /home/tiago/fiasco_builddir/main -nokdb -nowait -serial_esc -comspeed 115200 -comport 1 module /home/tiago/fiasco_builddir/sigma0 module /home/tiago/fiasco_builddir/names module /home/tiago/fiasco_builddir/dm_phys module /home/tiago/fiasco_builddir/l4io module /home/tiago/fiasco_builddir/name_server module /home/tiago/fiasco_builddir/flips-lxdrv module /home/tiago/fiasco_builddir/mini_ifconfig eth0 10.10.5.197 255.255.0.0 10.10.255.255 module /home/tiago/fiasco_builddir/testebroadcast ########################################################### is there any server missing? thanks for your help so far Tiago

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Kernel Module Pointers for L4Linux on Fiasco
by Julian Grizzard 11 Apr '05

11 Apr '05

Anyone have any pointers on using kernel modules with L4Linux? Here's the setup: i386 L4 Fiasco V.2 L4Linux third party kernel modules We've been playing with various modules trying to get them to work with the L4Linux kernel. Some modules compile fine against the L4Linux source; others give warnings. Further, some load fine but do not work properly; others complain about missing symbols. It is conceivable that we have non-L4Linux related issues but wanted to check and see if there is anything special to know about building modules for L4Linux? Specifically, what are possible reasons that a kernel module would work on a stock i386 arch Linux kernel but not work on the same version L4 arch Linux kernel? Thanks! -Julian

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Various things on log_net package
by Rene Wittmann 11 Apr '05

11 Apr '05

Hi, While trying to get the log server working for logging to network, I found some problems/bugs... And here is my report: L4DIR/pkg/log_net/server/src/tcpip.c: l.96 : in #define INITDRV(drv) the called function can give an error, but this error is just ignored (fct. init_ethernet always returns 0) l.264: (closing etherdev on error) if you select a wrong driver in init_ethernet, the system boot will fail with strange output over and over again (maybe just logging to normal console and go on booting is more desired??) L4DIR/pkg/log/server/src/logserver.c l.45: initializing buffer for net output if the buffer size is not given explicitly as command line switch the later buffer size is 0(!! not 4096 as expected). Therefore the logging to the network will not work. In order to prevent this you should put some lines right after parsing command line parameters in main(), e.g.: // if flushing to net && no buffer_size specified, use an initial value if (flush_to_net && !buffer_size){ buffer_size = 4096; } (or you should document it somewhere) BTW: to use the correct driver in init_ethernet for vmware, you should use "vlance" as network setting in vmware and "INITDRV(lance)" in init_ethernet, the drivers for 3com cards are not called 3c??? as I expected but can be used with "INITDRV(etherlink<??>)" with <??>="","2","3","16","plus" or "INITDRV(vortex)". In my opinion this should be documented somewhere. (in case it is already, and I was just too stupid to find it, ignore this remark...) Problem when using the logging to network within a program that uses the parse_cmd library I can't explain why this is the case, but when you use the log server compiled for network output and afterwards start an application that uses "parse_cmdline" the logging will not go to network, but to local console (even if you specify "-nolocal" on the log server). If you're interested in this bug, I can send you my sample code which is just a modification of rt_sched example in the hello-package Regards, Rene

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L4Linux Kernel Thread IDs
by Leon Brits 08 Apr '05

08 Apr '05

Hi all, I have a L4Linux kernel module which creates a kernel thread, but the new thread and the module has the same L4 thread ID [l4_myself()] while their PIDs are different as usual. Is this correct? Thanks Leon

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con deprecated?
by Stefan Kalkowski 08 Apr '05

08 Apr '05

hello list, i want to do a new build of the l4-tree after building a new gcc. i got the problem, that packages like proxygon, that uses l4con-headers don't pass through, because the con-package is marked as deprecated since 2 days and it's Makefile is modified, so that it won't build. I think it's only a naming convention problem and there should be a l4con replacement? Or is there any other reason, why con is obsolet? greetings stefan -- Stefan Kalkowski GNU PGP-Key: https://www.inf.tu-dresden.de/~sk852421

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Re: L4Linux Kernel Thread IDs
by Frank Mehnert 06 Apr '05

06 Apr '05

Leon, On Wednesday 06 April 2005 09:57, Leon Brits wrote: > I have a L4Linux kernel module which creates a kernel thread, but the > new thread and the module has the same L4 thread ID [l4_myself()] while > their PIDs are different as usual. > > Is this correct? Which L4Linux version do you talk about? 2.4? (Please post those messages to l4-hackers since I'm too busy to answer all your questions.) Frank -- ## Dept. of Computer Science, Dresden University of Technology, Germany ## ## http://os.inf.tu-dresden.de/~fm3 ##

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