On Thu, 10 May 2012 20:16:26 +0530, Nikunj A Dadhania <nikunj@xxxxxxxxxxxxxxxxxx> wrote: > On Thu, 10 May 2012 15:39:04 +0530, Nikunj A Dadhania <nikunj@xxxxxxxxxxxxxxxxxx> wrote: > > I had a discussion with Avi on IRC, he suggested running a trace on the > host for the sched: tracepoints > > So when I see the console of the guest, i can see the soft-lockup > messages. When I start tracing, soft-lockups disappear. > > Kernbench is started from the host; ps output: > 13359 pts/1 S+ 0:00 perf stat -a -- ssh root@192.168.123.11 cd /root/linux-src; kernbench -f -M -H -o 16 > /root/kbench.log > 13362 pts/1 S+ 0:00 ssh root@192.168.123.11 cd /root/linux-src; kernbench -f -M -H -o 16 > /root/kbench.log > 13373 pts/1 S+ 0:00 perf stat -a -- ssh root@192.168.123.12 cd /root/linux-src; kernbench -f -M -H -o 16 > /root/kbench.log > 13376 pts/1 S+ 0:00 ssh root@192.168.123.12 cd /root/linux-src; kernbench -f -M -H -o 16 > /root/kbench.log > 13387 pts/1 S+ 0:00 perf stat -a -- ssh root@192.168.123.13 cd /root/linux-src; kernbench -f -M -H -o 16 > /root/kbench.log > 13390 pts/1 S+ 0:00 ssh root@192.168.123.13 cd /root/linux-src; kernbench -f -M -H -o 16 > /root/kbench.log > 13401 pts/1 S+ 0:00 perf stat -a -- ssh root@192.168.123.14 cd /root/linux-src; kernbench -f -M -H -o 16 > /root/kbench.log > 13402 pts/1 S+ 0:00 ssh root@192.168.123.14 cd /root/linux-src; kernbench -f -M -H -o 16 > /root/kbench.log > > I have tried following commands trace-cmd: > 1) trace-cmd record -e kvm -e sched -b 100000 -p 13362 > 2) trace-cmd record -e sched -b 100000 -p 13362 > 3) trace-cmd record -e kvm -b 100000 -p 13362 > > I have tried trace-cmd on qemu pid as well, I see similar behaviour in > that case. > > Peterz/Ingo, Any clue on debugging this would help. > With CONFIG_DEBUG_SPINLOCK=y in guest config, I stop seeing the soft-lockup Nikunj -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html