Re: ULE nice bugs are fixed.

On Mon, 16 Jun 2003, Wiktor Niesiobedzki wrote:

> On Fri, Apr 11, 2003 at 04:40:17PM -0400, Jeff Roberson wrote:
> >
> > On Fri, 11 Apr 2003, Steve Kargl wrote:
> >
> > >
> > > I started to recompile the kernel and while sitting here decided
> > > to load linux-mozilla.  The system rebooted before linux-mozilla
> > > displayed a window.  I'm not sure this ULE related.
> > >
> > > Whoops.  The system just panic after coming back up from
> > > a linux-mozilla induce reboot.  I've left the machine
> > > at the db> prompt.
> > >
> > > Here's a hand transcribed backtrace.
> > >
> > > panic: Negative nice count.
> > > Stack backtrace
> > > bactrace
> > > panic
> > > kseq_nice_rem
> > > kseq_rem
> > > sched_switchout
> > > mi_switch
> > > msleep
> > > g_io_schedule_down
> > > g_down_procbody
> > > fork_exit
> > > fork_trampoline
> > >
> >
> > In ddb please type 'call kseq_print(0)'  This is on UP right?
> I'm seeing quite similar panic, when I do renice to lower (negative) value:
> ("Negative nice count.")
>
> (kgdb) bt
> #0  doadump () at ../../../kern/kern_shutdown.c:240
> #1  0xc018b374 in boot (howto=260) at ../../../kern/kern_shutdown.c:372
> #2  0xc018b6aa in panic () at ../../../kern/kern_shutdown.c:545
> #3  0xc01926a3 in mi_switch () at ../../../kern/kern_synch.c:481
> #4  0xc018b022 in boot (howto=256) at ../../../kern/kern_shutdown.c:312
> #5  0xc018b6aa in panic () at ../../../kern/kern_shutdown.c:545
> #6  0xc019dbe8 in kseq_nice_rem (kseq=0xc0312be0, nice=-10) at ../../../kern/sched_ule.c:324
> #7  0xc019e2b5 in sched_nice (kg=0xfffffff6, nice=-20) at ../../../kern/sched_ule.c:809
> #8  0xc0188eac in donice (td=0xc25fc850, p=0xc26c0790, n=-20) at ../../../kern/kern_resource.c:296
> #9  0xc0188b43 in setpriority (td=0xc25fc850, uap=0xcdd65d14) at ../../../kern/kern_resource.c:205
> #10 0xc0298b11 in syscall (frame=
>       {tf_fs = 47, tf_es = 47, tf_ds = 47, tf_edi = 87, tf_esi = -10, tf_ebp = -1077937064, tf_isp = -841589388, tf_ebx = -20, tf_edx = 0, tf_ecx = -1077937080, tf_eax = 96, tf_trapno = 12, tf_err = 2, tf_eip = 671874691, tf_cs = 31, tf_eflags = 659, tf_esp = -1077937108, tf_ss = 47}) at ../../../i386/i386/trap.c:1023
> #11 0xc0288d9d in Xint0x80_syscall () at {standard input}:138
> ---Can't read userspace from dump, or kernel process---
>
> The sources are from today. I also noticed, that 5.1-BETA (build around 9th of
> May) is working correctly.
>
> Also: I've noticed a strange behaviour - if I do nice -n -15 some_prog, it
> will get a nice of -10, and similiar with any other nice values (it +5 from
> what it suposed to be).
>
>
> Cheers,
>
> Wiktor Niesiobedzki
>

I'm looking into this now.  I'll give you a status update as soon as I've
found and fixed the problem.

Cheers,
Jeff