linux/include
Peter Zijlstra 1db49484f2 smp/hotplug: Hotplug state fail injection
Add a sysfs file to one-time fail a specific state. This can be used
to test the state rollback code paths.

Something like this (hotplug-up.sh):

  #!/bin/bash

  echo 0 > /debug/sched_debug
  echo 1 > /debug/tracing/events/cpuhp/enable

  ALL_STATES=`cat /sys/devices/system/cpu/hotplug/states | cut -d':' -f1`
  STATES=${1:-$ALL_STATES}

  for state in $STATES
  do
	  echo 0 > /sys/devices/system/cpu/cpu1/online
	  echo 0 > /debug/tracing/trace
	  echo Fail state: $state
	  echo $state > /sys/devices/system/cpu/cpu1/hotplug/fail
	  cat /sys/devices/system/cpu/cpu1/hotplug/fail
	  echo 1 > /sys/devices/system/cpu/cpu1/online

	  cat /debug/tracing/trace > hotfail-${state}.trace

	  sleep 1
  done

Can be used to test for all possible rollback (barring multi-instance)
scenarios on CPU-up, CPU-down is a trivial modification of the above.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: bigeasy@linutronix.de
Cc: efault@gmx.de
Cc: rostedt@goodmis.org
Cc: max.byungchul.park@gmail.com
Link: https://lkml.kernel.org/r/20170920170546.972581715@infradead.org
2017-09-25 22:11:44 +02:00
..
acpi ACPI / bus: Make ACPI_HANDLE() work for non-GPL code again 2017-09-19 22:42:31 +02:00
asm-generic Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 20:01:41 -07:00
clocksource
crypto
drm lib/interval_tree: fast overlap detection 2017-09-08 18:26:49 -07:00
dt-bindings Merge branch '4.14-features' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2017-09-15 20:43:33 -07:00
keys net: rxrpc: Replace time_t type with time64_t type 2017-08-29 10:16:00 +01:00
kvm
linux smp/hotplug: Hotplug state fail injection 2017-09-25 22:11:44 +02:00
math-emu
media media updates for v4.14-rc1 2017-09-07 12:53:14 -07:00
memory
misc
net net: prevent dst uses after free 2017-09-21 20:42:15 -07:00
pcmcia
ras
rdma More RDMA work and some op-structure constification from Chuck Lever, 2017-09-09 13:31:49 -07:00
scsi SCSI misc on 20170913 2017-09-13 10:47:14 -07:00
soc ARM: SoC driver updates for v4.14 2017-09-10 20:40:00 -07:00
sound sound updates for 4.14-rc1 2017-09-07 12:44:53 -07:00
target
trace Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-09-16 11:28:59 -07:00
uapi Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-09-23 05:41:27 -10:00
video
xen xen, arm64: drop dummy lookup_address() 2017-09-19 09:25:05 -04:00