linux/Documentation/cgroups, branch v3.16

Merge branch 'for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

2014-06-09T22:03:33Z

Pull cgroup updates from Tejun Heo: "A lot of activities on cgroup side. Heavy restructuring including locking simplification took place to improve the code base and enable implementation of the unified hierarchy, which currently exists behind a __DEVEL__ mount option. The core support is mostly complete but individual controllers need further work. To explain the design and rationales of the the unified hierarchy Documentation/cgroups/unified-hierarchy.txt is added. Another notable change is css (cgroup_subsys_state - what each controller uses to identify and interact with a cgroup) iteration update. This is part of continuing updates on css object lifetime and visibility. cgroup started with reference count draining on removal way back and is now reaching a point where csses behave and are iterated like normal refcnted objects albeit with some complexities to allow distinguishing the state where they're being deleted. The css iteration update isn't taken advantage of yet but is planned to be used to simplify memcg significantly" * 'for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (77 commits) cgroup: disallow disabled controllers on the default hierarchy cgroup: don't destroy the default root cgroup: disallow debug controller on the default hierarchy cgroup: clean up MAINTAINERS entries cgroup: implement css_tryget() device_cgroup: use css_has_online_children() instead of has_children() cgroup: convert cgroup_has_live_children() into css_has_online_children() cgroup: use CSS_ONLINE instead of CGRP_DEAD cgroup: iterate cgroup_subsys_states directly cgroup: introduce CSS_RELEASED and reduce css iteration fallback window cgroup: move cgroup->serial_nr into cgroup_subsys_state cgroup: link all cgroup_subsys_states in their sibling lists cgroup: move cgroup->sibling and ->children into cgroup_subsys_state cgroup: remove cgroup->parent device_cgroup: remove direct access to cgroup->children memcg: update memcg_has_children() to use css_next_child() memcg: remove tasks/children test from mem_cgroup_force_empty() cgroup: remove css_parent() cgroup: skip refcnting on normal root csses and cgrp_dfl_root self css cgroup: use cgroup->self.refcnt for cgroup refcnting ...

vmscan: memcg: always use swappiness of the reclaimed memcg

2014-06-06T23:08:17Z

Memory reclaim always uses swappiness of the reclaim target memcg (origin of the memory pressure) or vm_swappiness for global memory reclaim. This behavior was consistent (except for difference between global and hard limit reclaim) because swappiness was enforced to be consistent within each memcg hierarchy. After "mm: memcontrol: remove hierarchy restrictions for swappiness and oom_control" each memcg can have its own swappiness independent of hierarchical parents, though, so the consistency guarantee is gone. This can lead to an unexpected behavior. Say that a group is explicitly configured to not swapout by memory.swappiness=0 but its memory gets swapped out anyway when the memory pressure comes from its parent with a It is also unexpected that the knob is meaningless without setting the hard limit which would trigger the reclaim and enforce the swappiness. There are setups where the hard limit is configured higher in the hierarchy by an administrator and children groups are under control of somebody else who is interested in the swapout behavior but not necessarily about the memory limit. From a semantic point of view swappiness is an attribute defining anon vs. file proportional scanning of LRU which is memcg specific (unlike charges which are propagated up the hierarchy) so it should be applied to the particular memcg's LRU regardless where the memory pressure comes from. This patch removes vmscan_swappiness() and stores the swappiness into the scan_control structure. mem_cgroup_swappiness is then used to provide the correct value before shrink_lruvec is called. The global vm_swappiness is used for the root memcg. [hughd@google.com: oopses immediately when booted with cgroup_disable=memory] Signed-off-by: Michal Hocko Acked-by: Johannes Weiner Cc: Tejun Heo Signed-off-by: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Documentation/memcg: warn about incomplete kmemcg state

2014-06-04T23:54:00Z

Kmemcg is currently under development and lacks some important features. In particular, it does not have support of kmem reclaim on memory pressure inside cgroup, which practically makes it unusable in real life. Let's warn about it in both Kconfig and Documentation to prevent complaints arising. Signed-off-by: Vladimir Davydov Acked-by: Michal Hocko Cc: Johannes Weiner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: memcontrol: remove hierarchy restrictions for swappiness and oom_control

2014-06-04T23:53:58Z

Per-memcg swappiness and oom killing can currently not be tweaked on a memcg that is part of a hierarchy, but not the root of that hierarchy. Users have complained that they can't configure this when they turned on hierarchy mode. In fact, with hierarchy mode becoming the default, this restriction disables the tunables entirely. But there is no good reason for this restriction. The settings for swappiness and OOM killing are taken from whatever memcg whose limit triggered reclaim and OOM invocation, regardless of its position in the hierarchy tree. Allow setting swappiness on any group. The knob on the root memcg already reads the global VM swappiness, make it writable as well. Allow disabling the OOM killer on any non-root memcg. Signed-off-by: Johannes Weiner Cc: Michal Hocko Cc: Tejun Heo Cc: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

memcg: remove tasks/children test from mem_cgroup_force_empty()

2014-05-16T17:22:48Z

Tejun has correctly pointed out that tasks/children test in mem_cgroup_force_empty is not correct because there is no other locking which preserves this state throughout the rest of the function so both new tasks can join the group or new children groups can be added while somebody is writing to memory.force_empty. A new task would break mem_cgroup_reparent_charges expectation that all failures as described by mem_cgroup_force_empty_list are temporal and there is no way out. The main use case for the knob as described by Documentation/cgroups/memory.txt is to: " The typical use case for this interface is before calling rmdir(). Because rmdir() moves all pages to parent, some out-of-use page caches can be moved to the parent. If you want to avoid that, force_empty will be useful. " This means that reparenting is not really required as rmdir will reparent pages implicitly from the safe context. If we remove it from mem_cgroup_force_empty then we are safe even with existing tasks because the number of reclaim attempts is bounded. Moreover the knob still does what the documentation claims (modulo reparenting which doesn't make any difference) and users might expect. Longterm we want to deprecate the whole knob and put the reparented pages to the tail of parent LRU during cgroup removal. tj: Removed unused variable @cgrp from mem_cgroup_force_empty() Signed-off-by: Michal Hocko Acked-by: Johannes Weiner Acked-by: Li Zefan Signed-off-by: Tejun Heo

cgroup: add documentation about unified hierarchy

2014-04-25T22:28:02Z

Unified hierarchy will be the new version of cgroup interface. This patch adds Documentation/cgroups/unified-hierarchy.txt which describes the design and rationales of unified hierarchy. v2: Grammatical updates as per Randy Dunlap's review. Signed-off-by: Tejun Heo Cc: Randy Dunlap

memcg: rename high level charging functions

2014-04-07T23:35:57Z

mem_cgroup_newpage_charge is used only for charging anonymous memory so it is better to rename it to mem_cgroup_charge_anon. mem_cgroup_cache_charge is used for file backed memory so rename it to mem_cgroup_charge_file. Signed-off-by: Michal Hocko Cc: Johannes Weiner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

res_counter: remove interface for locked charging and uncharging

2014-04-07T23:35:54Z

The res_counter_{charge,uncharge}_locked() variants are not used in the kernel outside of the resource counter code itself, so remove the interface. Signed-off-by: David Rientjes Acked-by: Michal Hocko Cc: Johannes Weiner Cc: KAMEZAWA Hiroyuki Cc: Christoph Lameter Cc: Pekka Enberg Cc: Tejun Heo Cc: Mel Gorman Cc: Oleg Nesterov Cc: Rik van Riel Cc: Jianguo Wu Cc: Tim Hockin Cc: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media

2014-01-31T17:31:14Z

Pull media updates from Mauro Carvalho Chehab: - a new jpeg codec driver for Samsung Exynos (jpeg-hw-exynos4) - a new dvb frontend for ds2103 chipset (m88ds2103) - a new sensor driver for Samsung S5K5BAF UXGA (s5k5baf) - new drivers for R-Car VSP1 - a new radio driver: radio-raremono - a new tuner driver for ts2022 chipset (m88ts2022) - the analog part of em28xx is now a separate module that only load/runs if the device is not a pure digital TV device - added a staging driver for bcm2048 radio devices - the omap 2 video driver (omap24xx) was moved to staging. This driver is for an old hardware and uses a deprecated Kernel internal API. If nobody cares enough to fix it, it would be removed on a couple Kernel releases - the sn9c102 driver was moved to staging. This driver was replaced by gspca, and disabled on some distros, as almost all devices are known to work properly with gspca. It should be removed from kernel on a couple Kernel releases - lots of driver fixes, improvements and cleanups * 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (421 commits) [media] media: v4l2-dev: fix video device index assignment [media] rc-core: reuse device numbers [media] em28xx-cards: properly initialize the device bitmap [media] Staging: media: Fix line length exceeding 80 characters in as102_drv.c [media] Staging: media: Fix line length exceeding 80 characters in as102_fe.c [media] Staging: media: Fix quoted string split across line in as102_fe.c [media] media: st-rc: Add reset support [media] m2m-deinterlace: fix allocated struct type [media] radio-usb-si4713: fix sparse non static symbol warnings [media] em28xx-audio: remove needless check before usb_free_coherent() [media] au0828: Fix sparse non static symbol warning Revert "[media] go7007-usb: only use go->dev after allocated" [media] em28xx-audio: provide an error code when URB submit fails [media] em28xx: fix check for audio only usb interfaces when changing the usb alternate setting [media] em28xx: fix usb alternate setting for analog and digital video endpoints > 0 [media] em28xx: make 'em28xx_ctrl_ops' static em28xx-alsa: Fix error patch for init/fini [media] em28xx-audio: flush work at .fini [media] drxk: remove the option to load firmware asynchronously [media] em28xx: adjust period size at runtime ...

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

2014-01-25T19:17:34Z

Pull networking updates from David Miller: 1) BPF debugger and asm tool by Daniel Borkmann. 2) Speed up create/bind in AF_PACKET, also from Daniel Borkmann. 3) Correct reciprocal_divide and update users, from Hannes Frederic Sowa and Daniel Borkmann. 4) Currently we only have a "set" operation for the hw timestamp socket ioctl, add a "get" operation to match. From Ben Hutchings. 5) Add better trace events for debugging driver datapath problems, also from Ben Hutchings. 6) Implement auto corking in TCP, from Eric Dumazet. Basically, if we have a small send and a previous packet is already in the qdisc or device queue, defer until TX completion or we get more data. 7) Allow userspace to manage ipv6 temporary addresses, from Jiri Pirko. 8) Add a qdisc bypass option for AF_PACKET sockets, from Daniel Borkmann. 9) Share IP header compression code between Bluetooth and IEEE802154 layers, from Jukka Rissanen. 10) Fix ipv6 router reachability probing, from Jiri Benc. 11) Allow packets to be captured on macvtap devices, from Vlad Yasevich. 12) Support tunneling in GRO layer, from Jerry Chu. 13) Allow bonding to be configured fully using netlink, from Scott Feldman. 14) Allow AF_PACKET users to obtain the VLAN TPID, just like they can already get the TCI. From Atzm Watanabe. 15) New "Heavy Hitter" qdisc, from Terry Lam. 16) Significantly improve the IPSEC support in pktgen, from Fan Du. 17) Allow ipv4 tunnels to cache routes, just like sockets. From Tom Herbert. 18) Add Proportional Integral Enhanced packet scheduler, from Vijay Subramanian. 19) Allow openvswitch to mmap'd netlink, from Thomas Graf. 20) Key TCP metrics blobs also by source address, not just destination address. From Christoph Paasch. 21) Support 10G in generic phylib. From Andy Fleming. 22) Try to short-circuit GRO flow compares using device provided RX hash, if provided. From Tom Herbert. The wireless and netfilter folks have been busy little bees too. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2064 commits) net/cxgb4: Fix referencing freed adapter ipv6: reallocate addrconf router for ipv6 address when lo device up fib_frontend: fix possible NULL pointer dereference rtnetlink: remove IFLA_BOND_SLAVE definition rtnetlink: remove check for fill_slave_info in rtnl_have_link_slave_info qlcnic: update version to 5.3.55 qlcnic: Enhance logic to calculate msix vectors. qlcnic: Refactor interrupt coalescing code for all adapters. qlcnic: Update poll controller code path qlcnic: Interrupt code cleanup qlcnic: Enhance Tx timeout debugging. qlcnic: Use bool for rx_mac_learn. bonding: fix u64 division rtnetlink: add missing IFLA_BOND_AD_INFO_UNSPEC sfc: Use the correct maximum TX DMA ring size for SFC9100 Add Shradha Shah as the sfc driver maintainer. net/vxlan: Share RX skb de-marking and checksum checks with ovs tulip: cleanup by using ARRAY_SIZE() ip_tunnel: clear IPCB in ip_tunnel_xmit() in case dst_link_failure() is called net/cxgb4: Don't retrieve stats during recovery ...