At 2016-10-04 05:48:21, "Adam Lackorzynski" <adam@os.inf.tu-dresden.de> wrote: > >On Fri Sep 30, 2016 at 22:06:47 +0800, li94575 wrote: >> 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 with fiasco.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? > >Do you have others timers for each CPU? Maybe better (as easier), use >one timer and distribute the timer tick to other CPUs: There's a >timer_tick-broadcast and it is used in 3 BSPs. Does this help? > Yes , that solved my problem. Thank you so much!