Philippe, Yes, the patch you sent me works, timers do not stop and RTDM task in my driver continuous to run when realtime app is stopped by debugger.
My statement bellow was not clear. I meant that on the unpatched kernel, resuming execution of realtime app does not resume execution of the RTDM task. There are two functions lock_/unlock_timers(), are these functions used to stop/start timers when a breakpoint is hit? If yes, I can put some tracing information to check if timers are unblocked. Luis >-----Original Message----- >From: Philippe Gerum [mailto:[email protected]] >Sent: Thursday, August 19, 2010 12:43 PM >To: Herrera-Bendezu, Luis >Cc: [email protected] >Subject: RE: [Xenomai-help] RTDM task blocks when connecting gdb to realtime >task > > >On Thu, 2010-08-19 at 08:26 -0400, Herrera-Bendezu, Luis wrote: >> >-----Original Message----- >> >From: Philippe Gerum [mailto:[email protected]] >> >Sent: Wednesday, August 18, 2010 4:44 PM >> >To: Herrera-Bendezu, Luis >> >Cc: [email protected] >> >Subject: RE: [Xenomai-help] RTDM task blocks when connecting gdb to >> >realtime task >> > >> > >> >On Wed, 2010-08-18 at 13:29 -0400, Herrera-Bendezu, Luis wrote: >> >> Philippe, >> >> >> >> >-----Original Message----- >> >> >From: Philippe Gerum [mailto:[email protected]] >> >> >Sent: Wednesday, August 18, 2010 12:39 PM >> >> >To: Herrera-Bendezu, Luis >> >> >Cc: [email protected] >> >> >Subject: Re: [Xenomai-help] RTDM task blocks when connecting gdb to >> >> >realtime task >> >> > >> >> > >> >> >On Wed, 2010-08-18 at 12:03 -0400, Herrera-Bendezu, Luis wrote: >> >> >> Hello: >> >> >> >> >> >> I am using Xenomai 2.4.10 on PPC. An RTDM driver creates an RTDM task >> >> >> using rtdm_task_init() and goes to sleep periodically via function >> >> >> rtdm_task_sleep(). >> >> >> >> >> >> When driver is loaded, RTDM task executes as expected. Then a realtime >> >> >> application is started via gdbserver on target board and on a linux >> >> >> host >> >> >> a gdb client is connected to that board. As soon as gdb breakpoints the >> >> >> realtime application the RTDM task never returns from >> >> >> rtdm_task_sleep(). >> >> >> The application does not open the RTMD driver so at this point there is >> >> >> no interaction with the driver. >> >> >> >> >> >> The RTDM task is intr_sim and the timer is no longer firing >> >> >> # cat /proc/xenomai/timerstat/master >> >> >> CPU SCHEDULED FIRED TIMEOUT INTERVAL HANDLER NAME >> >> >> 0 29198042 9132085 3724750 - NULL >> >> >> [host-timer] >> >> >> 0 1340 1340 - - xnthread_ti >> >> >> intr_sim >> >> >> >> >> >> The realtime application is ancvbirt. >> >> >> # cat /proc/xenomai/sched >> >> >> CPU PID PRI PERIOD TIMEOUT TIMEBASE STAT NAME >> >> >> 0 0 -1 0 0 master R ROOT >> >> >> 0 0 90 0 0 master D >> >> >> intr_sim >> >> >> 0 1869 0 0 0 master XT >> >> >> ancvbirt >> >> >> >> >> >> Any ideas on the cause of the problem and fix? >> >> > >> >> >This is a side-effect of hitting a breakpoint in your application >> >> >introduced by Xenomai: all Xenomai timers are frozen system-wide, until >> >> >the application is continued. This includes the per-thread timer which >> >> >is used to have your RTDM task wake up after a delay. >> >> After continuing the application, the RTDM task does not resume execution. >> >> I had to reload driver to have it working again. >> >> > >> >> >There is a way to prevent this behavior, which was defined for internal >> >> >purposes only so far. Since Jan is not watching, here is a patch against >> >> >2.4.10 which happily butchers his nifty interface, that should prevent >> >> >the per-thread timers of _all_ RTDM tasks from being blocked in that >> >> >case, which may be enough to help you though: >> >> > >> >> >diff --git a/ksrc/skins/rtdm/drvlib.c b/ksrc/skins/rtdm/drvlib.c >> >> >index 65c630f..0295690 100644 >> >> >--- a/ksrc/skins/rtdm/drvlib.c >> >> >+++ b/ksrc/skins/rtdm/drvlib.c >> >> >@@ -144,6 +144,7 @@ int rtdm_task_init(rtdm_task_t *task, const char >> >> >*name, >> >> > res = xnpod_init_thread(task, rtdm_tbase, name, priority, 0, 0, >> >> > NULL); >> >> > if (res) >> >> > goto error_out; >> >> >+ task->rtimer.status |= XNTIMER_NOBLCK; >> >> > >> >> > if (period > 0) { >> >> > res = xnpod_set_thread_periodic(task, XN_INFINITE, >> >> >@@ -151,6 +152,7 @@ int rtdm_task_init(rtdm_task_t *task, const char >> >> >*name, >> >> > (rtdm_tbase, period)); >> >> > if (res) >> >> > goto cleanup_out; >> >> >+ task->ptimer.status |= XNTIMER_NOBLCK; >> >> > } >> >> > >> >> > res = xnpod_start_thread(task, 0, 0, XNPOD_ALL_CPUS, task_proc, >> >> > arg); >> >> > >> >> Yes, this patch avoids stopping the timers. I see the value on stopping >> >> the >> >> timers on the RTDM driver when application hits a breakpoint but for some >> >> reason timer does not recover. I am using Linux 2.6.30. >> > >> >Could you paste the output from: >> >/proc/xenomai/stat >> >/proc/xenomai/timerstat/master >> > >> >after the application has resumed execution? >> > >> >TIA, >> > >> > >> >-- >> >Philippe. >> > >> Status with application at breakpoint: >> # cat /proc/xenomai/stat >> CPU PID MSW CSW PF STAT %CPU NAME >> 0 0 0 14984 0 00400080 99.7 ROOT >> 0 0 0 3976 0 00000084 0.0 intr_sim >> 0 1261 1 1 1 00301380 0.0 ancvbirt >> 0 0 0 0 0 00000000 0.0 IRQ22: >> _vip_fpga_co...@2000000_r >> 0 0 0 337375 0 00000000 0.2 IRQ512: [timer] >> >> # cat /proc/xenomai/timerstat/master >> CPU SCHEDULED FIRED TIMEOUT INTERVAL HANDLER NAME >> 0 1005240 326161 1844335 - NULL [host-timer] >> 0 3976 3976 - - xnthread_ti intr_sim >> >> Status of application after application execution is resumed: >> # cat /proc/xenomai/stat >> CPU PID MSW CSW PF STAT %CPU NAME >> 0 0 0 15034 0 00400080 99.6 ROOT >> 0 0 0 3976 0 00000084 0.0 intr_sim >> 0 1261 2 2 2 00300380 0.0 ancvbirt >> 0 0 0 0 0 00000000 0.0 IRQ22: >> _vip_fpga_co...@2000000_r >> 0 0 0 428462 0 00000000 0.4 IRQ512: [timer] >> >> # cat /proc/xenomai/timerstat/master >> CPU SCHEDULED FIRED TIMEOUT INTERVAL HANDLER NAME >> 0 1314446 412961 410890 - NULL [host-timer] >> 0 3976 3976 - - xnthread_ti intr_sim >> 0 5 2 - - xnthread_ti >> AncVbiRt-in-int >> 0 4 1 - - xnthread_ti >> AncVbiRt-out-in >> 0 2 2 - - xnthread_ti >> AncVbiRt-client >> 0 3 1 - - xnthread_ti >> AncVbiRt-tsout >> 0 3 1 - - xnthread_ti AncVbiRt-pudi >> 0 1 1 - - xnthread_ti AncVbiRt-ancx >> 0 1 0 - - xnthread_ti AncVbiRt-vbix >> 0 1 0 - - xnthread_ti >> AncVbiRt-gpispl >> >> Notes: >> 1. GNU gdb Red Hat Linux (6.7-1rh) >> 2. GNU gdbserver Red Hat Linux (6.7-1rh) >> 3. set gdb to not stop/print/pass SIGXCPU signal. >> 4. Same behavior if program is executed within gdb and no breakpoints. > >Please check that you are running the modified kernel, and specifically >the updated xeno_rtdm module. This patch does work as expected. > >> >> Thanks, >> Luis > >-- >Philippe. > _______________________________________________ Xenomai-help mailing list [email protected] https://mail.gna.org/listinfo/xenomai-help
