linux/net
Glauber Costa 3f13461939 memcg: decrement static keys at real destroy time
We call the destroy function when a cgroup starts to be removed, such as
by a rmdir event.

However, because of our reference counters, some objects are still
inflight.  Right now, we are decrementing the static_keys at destroy()
time, meaning that if we get rid of the last static_key reference, some
objects will still have charges, but the code to properly uncharge them
won't be run.

This becomes a problem specially if it is ever enabled again, because now
new charges will be added to the staled charges making keeping it pretty
much impossible.

We just need to be careful with the static branch activation: since there
is no particular preferred order of their activation, we need to make sure
that we only start using it after all call sites are active.  This is
achieved by having a per-memcg flag that is only updated after
static_key_slow_inc() returns.  At this time, we are sure all sites are
active.

This is made per-memcg, not global, for a reason: it also has the effect
of making socket accounting more consistent.  The first memcg to be
limited will trigger static_key() activation, therefore, accounting.  But
all the others will then be accounted no matter what.  After this patch,
only limited memcgs will have its sockets accounted.

[akpm@linux-foundation.org: move enum sock_flag_bits into sock.h,
                            document enum sock_flag_bits,
                            convert memcg_proto_active() and memcg_proto_activated() to test_bit(),
                            redo tcp_update_limit() comment to 80 cols]
Signed-off-by: Glauber Costa <glommer@parallels.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Acked-by: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-29 16:22:28 -07:00
..
9p Autogenerated GPG tag for Rusty D1ADB8F1: 15EE 8D6C AB0E 7F0C F999 BFCB D920 0E6C D1AD B8F1 2012-05-21 20:20:23 -07:00
802 tokenring: delete all remaining driver support 2012-05-15 20:23:16 -04:00
8021q Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-05-16 22:17:37 -04:00
appletalk net: Convert all sysctl registrations to register_net_sysctl 2012-04-20 21:22:30 -04:00
atm Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2012-05-22 19:22:50 -07:00
ax25 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-04-23 23:15:17 -04:00
batman-adv batman-adv: unset the TT_CLIENT_PENDING flag if the new local entry already exists 2012-05-14 09:05:08 +02:00
bluetooth Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-05-24 11:54:29 -07:00
bridge ipv6: correct the ipv6 option name - Pad0 to Pad1 2012-05-17 15:49:51 -04:00
caif Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2012-05-22 19:22:50 -07:00
can can: fix sparse warning for cgw_list 2012-04-16 21:08:18 +02:00
ceph crush: include header for global symbols 2012-04-27 00:03:34 -04:00
core Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2012-05-23 17:42:39 -07:00
dcb net: dcb: add CEE notify calls 2012-04-25 19:47:17 -04:00
dccp net: include/net/sock.h cleanup 2012-05-17 04:50:21 -04:00
decnet net: Convert net_ratelimit uses to net_<level>_ratelimited 2012-05-15 13:45:03 -04:00
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 net, drivers/net: Convert compare_ether_addr_64bits to ether_addr_equal_64bits 2012-05-10 23:33:01 -04:00
ieee802154 ieee802154: interface type to be added 2012-05-16 15:17:08 -04:00
ipv4 memcg: decrement static keys at real destroy time 2012-05-29 16:22:28 -07:00
ipv6 ipv6/exthdrs: strict Pad1 and PadN check 2012-05-20 16:58:39 -04:00
ipx ipx: Remove spurious NULL checking in ipx_ioctl(). 2012-05-19 00:51:04 -04:00
irda net: Convert all sysctl registrations to register_net_sysctl 2012-04-20 21:22:30 -04:00
iucv Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2012-03-22 18:15:32 -07:00
key net: cleanup unsigned to unsigned int 2012-04-15 12:44:40 -04:00
l2tp net: l2tp: Standardize logging styles 2012-05-17 04:34:38 -04:00
lapb lapb: Neaten debugging 2012-05-17 18:45:20 -04:00
llc net: include/net/sock.h cleanup 2012-05-17 04:50:21 -04:00
mac80211 Merge git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next 2012-05-22 15:18:06 -04:00
mac802154 mac802154: monitor device support 2012-05-16 15:17:08 -04:00
netfilter Merge branch 'for-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu 2012-05-22 17:37:47 -07:00
netlabel netlabel: use GFP flags from caller instead of GFP_ATOMIC 2012-03-22 19:29:57 -04:00
netlink af_netlink: drop_monitor/dropwatch friendly 2012-04-24 00:35:14 -04:00
netrom net: Convert all sysctl registrations to register_net_sysctl 2012-04-20 21:22:30 -04:00
nfc NFC: Queue I frame fragments to the LLCP sockets queue tail 2012-05-16 13:08:14 -04:00
openvswitch Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-05-16 22:17:37 -04:00
packet af_packet: packet_getsockopt() cleanup 2012-04-21 16:36:42 -04:00
phonet net: Convert all sysctl registrations to register_net_sysctl 2012-04-20 21:22:30 -04:00
rds sock: Introduce named constants for sk_reuse 2012-04-21 15:52:25 -04:00
rfkill device.h: cleanup users outside of linux/include (C files) 2012-03-11 14:27:37 -04:00
rose net: Convert all sysctl registrations to register_net_sysctl 2012-04-20 21:22:30 -04:00
rxrpc net: cleanup unsigned to unsigned int 2012-04-15 12:44:40 -04:00
sched Merge branch 'for-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup 2012-05-22 17:40:19 -07:00
sctp Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-05-16 22:17:37 -04:00
sunrpc NFS client updates for Linux 3.5 2012-05-29 10:43:51 -07:00
tipc tipc: compress out gratuitous extra carriage returns 2012-04-30 15:53:56 -04:00
unix net: sock_diag_handler structs can be const 2012-04-25 20:46:59 -04:00
wanrouter wanrouter: Remove kernel_lock annotations 2011-11-07 13:27:30 -05:00
wimax net: cleanup unsigned to unsigned int 2012-04-15 12:44:40 -04:00
wireless Merge git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next 2012-05-22 15:18:06 -04:00
x25 net: add a limit parameter to sk_add_backlog() 2012-04-23 22:28:28 -04:00
xfrm Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2012-05-21 20:27:36 -07:00
compat.c Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2012-05-21 20:27:36 -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 Merge branch 'for-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu 2012-05-22 17:37:47 -07:00
sysctl_net.c net: delete all instances of special processing for token ring 2012-05-15 20:14:35 -04:00