linux/include
Tejun Heo aa226ff4a1 cgroup: make sure a parent css isn't offlined before its children
There are three subsystem callbacks in css shutdown path -
css_offline(), css_released() and css_free().  Except for
css_released(), cgroup core didn't guarantee the order of invocation.
css_offline() or css_free() could be called on a parent css before its
children.  This behavior is unexpected and led to bugs in cpu and
memory controller.

This patch updates offline path so that a parent css is never offlined
before its children.  Each css keeps online_cnt which reaches zero iff
itself and all its children are offline and offline_css() is invoked
only after online_cnt reaches zero.

This fixes the memory controller bug and allows the fix for cpu
controller.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-and-tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reported-by: Brian Christiansen <brian.o.christiansen@gmail.com>
Link: http://lkml.kernel.org/g/5698A023.9070703@de.ibm.com
Link: http://lkml.kernel.org/g/CAKB58ikDkzc8REt31WBkD99+hxNzjK4+FBmhkgS+NVrC9vjMSg@mail.gmail.com
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
2016-01-22 10:42:57 -05:00
..
acpi Merge branches 'acpica', 'acpi-video' and 'acpi-fan' 2016-01-21 00:41:59 +01:00
asm-generic Merge branch 'akpm' (patches from Andrew) 2016-01-21 12:32:08 -08:00
clocksource arm64: KVM: Implement timer save/restore 2015-12-14 11:30:39 +00:00
crypto Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2016-01-17 19:13:15 -08:00
drm Merge tag 'topic/drm-misc-2016-01-17' of git://anongit.freedesktop.org/drm-intel into drm-next 2016-01-18 07:01:16 +10:00
dt-bindings ARM: SoC driver updates for v4.5 2016-01-20 18:42:30 -08:00
keys Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity into next 2015-12-26 16:06:53 +11:00
kvm KVM: arm/arm64: vgic-v3: Make the LR indexing macro public 2015-12-14 11:30:38 +00:00
linux cgroup: make sure a parent css isn't offlined before its children 2016-01-22 10:42:57 -05:00
math-emu
media [media] media-entitiy: add a function to create multiple links 2016-01-11 12:19:26 -02:00
memory
misc
net net: drop tcp_memcontrol.c 2016-01-20 17:09:18 -08:00
pcmcia
ras
rdma IB/mad: Require CM send method for everything except ClassPortInfo 2015-12-08 12:19:11 -05:00
rxrpc
scsi Merge branch 'jejb-scsi' into misc 2016-01-07 15:51:13 -08:00
soc ARM: SoC driver updates for v4.5 2016-01-20 18:42:30 -08:00
sound ALSA: hda_intel: add card number to irq description 2016-01-12 21:05:16 +01:00
target Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2016-01-20 17:20:53 -08:00
trace Merge branch 'for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2016-01-18 12:44:40 -08:00
uapi Merge branch 'for-4.5/nvme' of git://git.kernel.dk/linux-block 2016-01-21 19:58:02 -08:00
video omapdss: remove CONFIG_OMAP2_DSS_VENC from omapdss.h 2015-12-29 11:07:46 +02:00
xen Merge branch 'for-4.5/drivers' of git://git.kernel.dk/linux-block 2016-01-21 18:19:38 -08:00
Kbuild