At 2016-09-23 05:31:52, "Adam Lackorzynski" <adam@os.inf.tu-dresden.de> wrote: > >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. >I have to admit that there may be a problem with the configuration of the generic timer,but I donot know where the problem. Before this, the generic timer can run well withfiasco.oc-r56+genode+l4linux3.9, I do not make any changes and move the bsp codefor this newer fiasco version.I replace generic timer with Aptimer, then l4linux can run well. So, If I want to assign anAptimer for each CPU, is there any ready-made case for reference?