Re: [RT] lockdep munching nr_list_entries like popcorn

Mike Galbraith
2017-02-17T20:55:47Z

On Thu, 2017-02-16 at 19:06 +0100, Mike Galbraith wrote:
> On Thu, 2017-02-16 at 15:53 +0100, Sebastian Andrzej Siewior wrote:
> > On 2017-02-16 15:42:59 [+0100], Mike Galbraith wrote:
> > >
> > > Weeell, I'm trying to cobble something kinda like that together using
> > > __RT_SPIN_INITIALIZER() instead, but seems mean ole Mr. Compiler NAKs
> > > the PER_CPU_DEP_MAP_INIT() thingy.
> > >
> > > CC mm/swap.o
> > > mm/swap.c:54:689: error: braced-group within expression allowed only
> > > inside a function
> >
> > so this is what I have now. I need to get the `static' symbol working
> > again and PER_CPU_DEP_MAP_INIT but aside from that it seems to do its
> > job.
>
> ...
>
> Yeah, works, I should be able to do an ltp run with stock lockdep
> settings without it taking it's toys and going home in a snit.
>
> berio:/sys/kernel/debug/tracing/:[0]# !while
> while sleep 60; do tail -1 trace; done
> <...>-10315 [064] d...1.. 226.953935: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 14223
> w-13148 [120] d...111 287.414978: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 14465
> w-16492 [089] d...111 347.128742: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 14653
> (starts kbuild loop)
> btrfs-transacti-1964 [016] d...1.. 411.101549: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 17011
> <...>-100268 [127] d...112 472.271769: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 18153
> w-18864 [011] d...1.. 534.386443: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 18543
> <...>-50390 [035] dN..2.. 597.794164: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 18765
> <...>-80098 [127] d...111 659.912145: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 18977
> checkproc-11123 [017] d...1.. 721.483463: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 19247
> -0 [055] d..h5.. 782.685953: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 19383
> <...>-93632 [055] d...111 835.527817: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 19441

And now Thomas's patch. Spiffiness. Now to start ltp.

berio:/sys/kernel/debug/tracing/:[0]# !while
while sleep 60; do tail -1 trace; done
<...>-12462 [105] d...1.. 211.489528: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 12847
btrfs-transacti-3136 [002] d...211 272.672777: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 12947
irq/155-eth2-Tx-4495 [096] dN..213 332.035236: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 13001
(starts kbuild loop)
<...>-44245 [087] d...114 396.892748: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 13917
<...>-105411 [067] dN..211 457.708259: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 14367
w-21800 [113] dN..2.. 519.231735: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 14449
modpost-31558 [020] d....11 576.065855: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 14601
kworker/dying-11860 [133] d...112 637.170497: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 14679
<...>-118853 [055] d....11 703.884755: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 14759
<...>-52143 [090] d...1.. 767.624735: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 14813
<...>-71788 [126] d...1.. 829.160330: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 14857
kworker/u289:5-2991 [002] d...1.. 892.402939: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 14883
sh-15106 [008] d...211 953.172196: add_lock_to_list.isra.24.constprop.42: nr_list_entries: 14937
>