2009/5/20 GeunSik Lim <leemgs1@xxxxxxxxx>: > > > Dear Ingo, > > > I made 2 patch files again about static prioriy levels according to ingo's advice > and explanation. (Reference: http://marc.info/?t=124211992800003&r=1&w=2 archives. ) > > Fix static priority related range and chart map(userspace/kernelspace) of ftrace. > - about chart map of static priority in ftrace.txt file > - about static priority levels(range) in sched-rt-group.txt file > > > commit d6af702008117ca489a2f5476239d1688a517e98 > Author: GeunSik,Lim <leemgs1@xxxxxxxxx> > Date: Tue May 12 17:20:32 2009 +0900 > > sched: fix typo in sched-rt-group.txt file > > Fix typo about static priority's range. > > * Kernel Space priority 0(high) to 99(low) --> User Space RT priority 99(high) to 1(low) > * Kernel Space priority 100(high) to 139(low)--> User Space nice -20(high) to 19(low) > Ingo, I want to change some descriptions according to below discussion. before) * Kernel Space priority 0(high) to 99(low) --> User Space RT priority 99(high) to 1(low) after) * Kernel Space priority 0(high) to 98(low) --> User Space RT priority 99(high) to 1(low) I want to your advice and opinion about this changes. If I mistook, Please correct me. thks. Steven Rostedt: Shouldn't that be: Kernel priority: 0(high) to 98(low) ==> user RT priority 99(high) to 1(low) GeunSik Lim : Thank you for your opinion. I think about corrected expression for quick chart to map between kernel space and user space in ftrace . Steven Rostedt: 100 items does not map to 99. Which begs the question, what can have internal kernel priority 99? GeunSik Lim : ok. Below example is about kernel (static) priority 99 that you said. please, refer to http://www.kernel.org/doc/man-pages/online/pages/man2/sched_setscheduler.2.html webpage. For processes scheduled under one of the normal scheduling policies (SCHED_OTHER, SCHED_IDLE, SCHED_BATCH), sched_priority is not used in scheduling decisions (it must be specified as 0). int main (int argc, char **argv) { int pidnumber, ret; struct sched_param p; p.sched_priority = 0; <------ Kernel (static) priority. if (argc != 2) { printf("usage: setbatch <pid>\n"); exit(-1); } pidnumber = atol(argv[1]); /* 3 = Number of SCHED_BATCH Constant */ ret = sched_setscheduler(pidnumber, 3, &p); if (ret) { printf("could not set pid %d to SCHED_BATCH: err %d.\n", pid, ret); return -1; } printf("pid %d is SCHED_BATCH from now on.\n", pid); return 0; } > > Processes scheduled with SCHED_OTHER or SCHED_BATCH must be assigned > the static priority 0. Processes scheduled under SCHED_FIFO or SCHED_RR > can have a static priority in the range 1 to 99. > (reference: $> man 2 sched_setscheduler) > > Signed-off-by: GeunSik Lim <geunsik.lim@xxxxxxxxxxx> > > diff --git a/Documentation/scheduler/sched-rt-group.txt b/Documentation/scheduler/sched-rt-group.txt > index 5ba4d3f..1537146 100644 > --- a/Documentation/scheduler/sched-rt-group.txt > +++ b/Documentation/scheduler/sched-rt-group.txt > @@ -169,7 +169,7 @@ get their allocated time. > > Implementing SCHED_EDF might take a while to complete. Priority Inheritance is > the biggest challenge as the current linux PI infrastructure is geared towards > -the limited static priority levels 0-139. With deadline scheduling you need to > +the limited static priority levels 0-99. With deadline scheduling you need to > do deadline inheritance (since priority is inversely proportional to the > deadline delta (deadline - now). > > > > > ----------------------------------------------- > To unsubscribe from this list: send the line "unsubscribe linux-***" > in the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > > GeunSik Lim (ELS - OS Group - S/W Lab - SAIT - SAMSUNG) > e-Mail :1) geunsik.lim@xxxxxxxxxxx > 2) leemgs@xxxxxxxxx , leemgs1@xxxxxxxxx > HomePage: http://intomail.dnip.net/invain/me/ > ----------------------------------------------- > -- Regards, GeunSik Lim -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
