On Thu Sep 22, 2016 at 22:32:28 +0800, li94575 wrote: > Hi, adam > >On Mon Sep 19, 2016 at 22:55:52 +0800, li94575 wrote: > >> I compiled the l4re-snapshot-2014092821 with the default modules.list, > >> and everything seems goes > >> well. However, L4Linux would stop at "Calibrating delay loop ...", because > >> the value of jiffies did not change. > >> Timer thread has not generate soft interrupt? If I entered jdb via ESC at > >> this time, and quit via "g", then > >> l4linux can run again. It makes me confused so much. > >> Any help or suggestion will be very welcome. > > > >This behavior typically indicates that there's an issue with Fiasco's > >timer interrupt or with the user-level one in L4Linux. > >For a start you could add e.g. a printk(".\n") in timer_thread in > >arch/l4/kernel/timer.c to see if it really does something. > >Does 'hello' work? > >Although it's a bit of work you could also compare the code of your > >snapshot and a recent one if there's any significant change (i.e. fix) > >that might be relevant. Check arch/l4/kernel/timer.c > >and src/kern/arm/timer-arm-generic.cpp and > >src/kern/arm/generic_timer.cpp in the Fiasco kernel. > > 'Hello' can work well, which prints "Hello World!" circularly. I add > printk(".\n") in timer_thread in arch/l4/kernel/timer.c, and found > timer_thread stop at l4_ipc_reply_and_wait(u, t, &l, to) > afterinitializing the variable ¡®increment¡¯.
printk and any other Linux functionaliy cannot be used in this function because the timer_thread isn't run in a Linux context. It's run in an L4 thread next to Linux. (Sorry for my mistake of writing printk above, I actually really meant to write LOG_printf.) > However, if I use > LOG_printf() for printing, the phenomenon is different, that > timer_thread trigers a soft interrupt once. I have checked > src/kern/arm/timer-arm-generic.cpp and src/kern/arm/generic_timer.cpp > in the Fiasco kernel, there is less likely to be a problem with them. So there's still a problem somewhere. Do you think you could try with a more recent L4Re version? I remember vaguely that I might have already seen this behavior but this would be long ago. Adam -- Adam a...@os.inf.tu-dresden.de Lackorzynski http://os.inf.tu-dresden.de/~adam/ _______________________________________________ l4-hackers mailing list l4-hackers@os.inf.tu-dresden.de http://os.inf.tu-dresden.de/mailman/listinfo/l4-hackers