linux/net
Tejun Heo 8c7f6edbda cgroup: mark subsystems with broken hierarchy support and whine if cgroups are nested for them
Currently, cgroup hierarchy support is a mess.  cpu related subsystems
behave correctly - configuration, accounting and control on a parent
properly cover its children.  blkio and freezer completely ignore
hierarchy and treat all cgroups as if they're directly under the root
cgroup.  Others show yet different behaviors.

These differing interpretations of cgroup hierarchy make using cgroup
confusing and it impossible to co-mount controllers into the same
hierarchy and obtain sane behavior.

Eventually, we want full hierarchy support from all subsystems and
probably a unified hierarchy.  Users using separate hierarchies
expecting completely different behaviors depending on the mounted
subsystem is deterimental to making any progress on this front.

This patch adds cgroup_subsys.broken_hierarchy and sets it to %true
for controllers which are lacking in hierarchy support.  The goal of
this patch is two-fold.

* Move users away from using hierarchy on currently non-hierarchical
  subsystems, so that implementing proper hierarchy support on those
  doesn't surprise them.

* Keep track of which controllers are broken how and nudge the
  subsystems to implement proper hierarchy support.

For now, start with a single warning message.  We can whine louder
later on.

v2: Fixed a typo spotted by Michal. Warning message updated.

v3: Updated memcg part so that it doesn't generate warning in the
    cases where .use_hierarchy=false doesn't make the behavior
    different from root.use_hierarchy=true.  Fixed a typo spotted by
    Glauber.

v4: Check ->broken_hierarchy after cgroup creation is complete so that
    ->create() can affect the result per Michal.  Dropped unnecessary
    memcg root handling per Michal.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Li Zefan <lizefan@huawei.com>
Acked-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: Glauber Costa <glommer@parallels.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Turner <pjt@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2012-09-14 12:01:16 -07:00
..
9p net: Fix (nearly-)kernel-doc comments for various functions 2012-07-10 23:13:45 -07:00
802 tokenring: delete all remaining driver support 2012-05-15 20:23:16 -04:00
8021q vlan: clean up vlan_dev_hard_start_xmit() 2012-08-14 14:33:32 -07:00
appletalk net: Fix (nearly-)kernel-doc comments for various functions 2012-07-10 23:13:45 -07:00
atm atm: fix info leak via getsockname() 2012-08-15 21:36:30 -07:00
ax25 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-07-19 11:17:30 -07:00
batman-adv batman-adv: Fix mem leak in the batadv_tt_local_event() function 2012-08-08 16:04:04 -07:00
bluetooth Bluetooth: L2CAP - Fix info leak via getsockname() 2012-08-15 21:36:31 -07:00
bridge bridge: fix rcu dereference outside of rcu_read_lock 2012-08-15 15:09:41 -07:00
caif caif: Do not dereference NULL in chnl_recv_cb() 2012-08-20 02:47:49 -07:00
can can: gw: Remove pointless casts 2012-07-10 22:36:17 +02:00
ceph libceph: avoid truncation due to racing banners 2012-08-21 15:55:27 -07:00
core cgroup: mark subsystems with broken hierarchy support and whine if cgroups are nested for them 2012-09-14 12:01:16 -07:00
dcb net: Fix non-kernel-doc comments with kernel-doc start marker 2012-07-10 23:13:45 -07:00
dccp dccp: fix info leak via getsockopt(DCCP_SOCKOPT_CCID_TX_INFO) 2012-08-15 21:36:31 -07:00
decnet ipv4: Restore old dst_free() behavior. 2012-07-31 14:41:38 -07:00
dns_resolver Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2012-05-21 20:27:36 -07:00
dsa dsa: Convert compare_ether_addr to ether_addr_equal 2012-05-09 20:49:19 -04:00
ethernet ipx: move peII functions 2012-07-19 10:48:00 -07:00
ieee802154 6lowpan: Change byte order when storing/accessing to len field 2012-07-16 22:52:02 -07:00
ipv4 Merge branch 'master' of git://1984.lsi.us.es/nf 2012-08-31 13:06:37 -04:00
ipv6 net: ipv6: fix error return code 2012-08-31 16:27:48 -04:00
ipx ipx: move peII functions 2012-07-19 10:48:00 -07:00
irda irda: Fix typo in irda 2012-07-16 23:23:52 -07:00
iucv net: remove skb_orphan_try() 2012-06-15 15:30:15 -07:00
key net: cleanup unsigned to unsigned int 2012-04-15 12:44:40 -04:00
l2tp l2tp: avoid to use synchronize_rcu in tunnel free function 2012-08-30 12:31:03 -04:00
lapb lapb: Neaten debugging 2012-05-17 18:45:20 -04:00
llc llc: fix info leak via getsockname() 2012-08-15 21:36:31 -07:00
mac80211 Merge branch 'for-john' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211 2012-08-23 09:51:15 -04:00
mac802154 mac802154: sparse warnings: make symbols static 2012-07-12 07:54:45 -07:00
netfilter netfilter: nf_conntrack: fix racy timer handling with reliable events 2012-08-31 15:50:28 +02:00
netlabel netlabel: use GFP flags from caller instead of GFP_ATOMIC 2012-03-22 19:29:57 -04:00
netlink netlink: fix possible spoofing from non-root processes 2012-08-24 13:36:09 -04:00
netrom net: Convert all sysctl registrations to register_net_sysctl 2012-04-20 21:22:30 -04:00
nfc Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next into for-davem 2012-07-20 12:30:48 -04:00
openvswitch Revert "openvswitch: potential NULL deref in sample()" 2012-07-27 13:45:51 -07:00
packet af_packet: match_fanout_group() can be static 2012-08-23 09:27:12 -07:00
phonet net: remove my future former mail address 2012-06-17 16:29:38 -07:00
rds rds: set correct msg_namelen 2012-07-23 01:01:44 -07:00
rfkill rfkill: Add the capability to switch all devices of all type in __rfkill_switch_all(). 2012-06-06 15:18:17 -04:00
rose net: Convert all sysctl registrations to register_net_sysctl 2012-04-20 21:22:30 -04:00
rxrpc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-07-10 23:56:33 -07:00
sched cgroup: mark subsystems with broken hierarchy support and whine if cgroups are nested for them 2012-09-14 12:01:16 -07:00
sctp netvm: prevent a stream-specific deadlock 2012-07-31 18:42:47 -07:00
sunrpc NFS client bugfixes for Linux 3.6 2012-09-13 09:04:13 +08:00
tipc tipc: remove print_buf and deprecated log buffer code 2012-07-13 19:34:43 -04:00
unix af_netlink: force credentials passing [CVE-2012-3520] 2012-08-21 14:53:01 -07:00
wanrouter wanmain: comparing array with NULL 2012-07-24 13:55:21 -07:00
wimax net: cleanup unsigned to unsigned int 2012-04-15 12:44:40 -04:00
wireless cfg80211: process pending events when unregistering net device 2012-08-06 14:29:58 -04:00
x25 net: Fix (nearly-)kernel-doc comments for various functions 2012-07-10 23:13:45 -07:00
xfrm net/xfrm/xfrm_state.c: fix error return code 2012-08-31 16:27:48 -04:00
compat.c net: Fix references to out-of-scope variables in put_cmsg_compat() 2012-07-22 17:50:49 -07:00
Kconfig net: drop NET dependency from HAVE_BPF_JIT 2012-05-21 12:50:12 -07:00
Makefile econet: remove ancient bug ridden protocol 2012-05-18 01:35:08 -04:00
nonet.c
socket.c Fix order of arguments to compat_put_time[spec|val] 2012-09-05 18:34:13 -07:00
sysctl_net.c net: delete all instances of special processing for token ring 2012-05-15 20:14:35 -04:00