Re: SMP status ?

[BERTRAND Joel <joel.bertrand%systella.fr@localhost>]

matthew green a écrit :
> i've commited a change to -current that should work around this problem,
> so any stability issues should be gone.  it's just a workaround but it is
> worth updating to since it makes things mostly work, at least on my SS20.
>
> it still has the problem, but doesn't crash now, and the "savefp null ipi"
> event counters will slowly increase.
>
> if you're adventurous, please try -current sources and apply this patch:
>
>         http://www.netbsd.org/~mrg/sparc.kpreempt.diff
>
> for me it's run for almost 2 hours without a problem reported.  i chose
> the various points to add these new kpreempt_disable() calls by reviewing
> what the x86 platform does for it.  it *probably* contains points where
> preemption is disabled unnecessarily.

	I have applied this patch on my SS20 (with only dual Ross, I shall test 
a configuration with quad Ross later).

        dmesg shows:

NetBSD 5.99.43 (GENERIC.MP) #0: Fri Jan 14 17:28:22 CET 2011
        root@riemann:/usr/src/obj/sys/arch/sparc/compile/GENERIC.MP
total memory = 511 MB
avail memory = 496 MB
timecounter: Timecounters tick every 10.000 msec
bootpath: 
/iommu@f,e0000000/sbus@f,e0001000/espdma@f,400000/esp@f,800000/sd@3,0
mainbus0 (root): SUNW,SPARCstation-20: hostid 72786e83
cpu0 at mainbus0: mid 8: RT620/625 @ 200 MHz, on-chip FPU
cpu0: 512K byte write-back, 32 bytes/line, sw flush: cache enabled
cpu1 at mainbus0: mid 10: RT620/625 @ 200 MHz, on-chip FPU
cpu1: 512K byte write-back, 32 bytes/line, sw flush: cache enabled
...
cpu0: booting secondary processors: cpu1
...

and I can see some stray interrupt messages :
stray interrupt cpu0 ipl 0xc pc=0xf0148abc npc=0xf0148ac0 
psr=0x1e4000c6<S,PS>
stray interrupt cpu0 ipl 0xc pc=0xf0148b4c npc=0xf0148b50 
psr=0x1e8000c6<S,PS>
stray interrupt cpu0 ipl 0xc pc=0xf0148b4c npc=0xf0148b50 
psr=0x1e8000c6<S,PS>

	This SS20 is building distribution with -j2 and your patch seems to fix 
stability issue. Thanks a lot.

        Regards,

        JKB