user/sven/linux.git/kernel/cgroup.c, branch v3.17-rc2

Merge branch 'for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

2014-08-04T17:11:28Z

Pull cgroup changes from Tejun Heo: "Mostly changes to get the v2 interface ready. The core features are mostly ready now and I think it's reasonable to expect to drop the devel mask in one or two devel cycles at least for a subset of controllers. - cgroup added a controller dependency mechanism so that block cgroup can depend on memory cgroup. This will be used to finally support IO provisioning on the writeback traffic, which is currently being implemented. - The v2 interface now uses a separate table so that the interface files for the new interface are explicitly declared in one place. Each controller will explicitly review and add the files for the new interface. - cpuset is getting ready for the hierarchical behavior which is in the similar style with other controllers so that an ancestor's configuration change doesn't change the descendants' configurations irreversibly and processes aren't silently migrated when a CPU or node goes down. All the changes are to the new interface and no behavior changed for the multiple hierarchies" * 'for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (29 commits) cpuset: fix the WARN_ON() in update_nodemasks_hier() cgroup: initialize cgrp_dfl_root_inhibit_ss_mask from !->dfl_files test cgroup: make CFTYPE_ONLY_ON_DFL and CFTYPE_NO_ internal to cgroup core cgroup: distinguish the default and legacy hierarchies when handling cftypes cgroup: replace cgroup_add_cftypes() with cgroup_add_legacy_cftypes() cgroup: rename cgroup_subsys->base_cftypes to ->legacy_cftypes cgroup: split cgroup_base_files[] into cgroup_{dfl|legacy}_base_files[] cpuset: export effective masks to userspace cpuset: allow writing offlined masks to cpuset.cpus/mems cpuset: enable onlined cpu/node in effective masks cpuset: refactor cpuset_hotplug_update_tasks() cpuset: make cs->{cpus, mems}_allowed as user-configured masks cpuset: apply cs->effective_{cpus,mems} cpuset: initialize top_cpuset's configured masks at mount cpuset: use effective cpumask to build sched domains cpuset: inherit ancestor's masks if effective_{cpus, mems} becomes empty cpuset: update cs->effective_{cpus, mems} when config changes cpuset: update cpuset->effective_{cpus,mems} at hotplug cpuset: add cs->effective_cpus and cs->effective_mems cgroup: clean up sane_behavior handling ...

Merge branch 'for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu

2014-08-04T17:09:27Z

Pull percpu updates from Tejun Heo: - Major reorganization of percpu header files which I think makes things a lot more readable and logical than before. - percpu-refcount is updated so that it requires explicit destruction and can be reinitialized if necessary. This was pulled into the block tree to replace the custom percpu refcnting implemented in blk-mq. - In the process, percpu and percpu-refcount got cleaned up a bit * 'for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (21 commits) percpu-refcount: implement percpu_ref_reinit() and percpu_ref_is_zero() percpu-refcount: require percpu_ref to be exited explicitly percpu-refcount: use unsigned long for pcpu_count pointer percpu-refcount: add helpers for ->percpu_count accesses percpu-refcount: one bit is enough for REF_STATUS percpu-refcount, aio: use percpu_ref_cancel_init() in ioctx_alloc() workqueue: stronger test in process_one_work() workqueue: clear POOL_DISASSOCIATED in rebind_workers() percpu: Use ALIGN macro instead of hand coding alignment calculation percpu: invoke __verify_pcpu_ptr() from the generic part of accessors and operations percpu: preffity percpu header files percpu: use raw_cpu_*() to define __this_cpu_*() percpu: reorder macros in percpu header files percpu: move {raw|this}_cpu_*() definitions to include/linux/percpu-defs.h percpu: move generic {raw|this}_cpu_*_N() definitions to include/asm-generic/percpu.h percpu: only allow sized arch overrides for {raw|this}_cpu_*() ops percpu: reorganize include/linux/percpu-defs.h percpu: move accessors from include/linux/percpu.h to percpu-defs.h percpu: include/asm-generic/percpu.h should contain only arch-overridable parts percpu: introduce arch_raw_cpu_ptr() ...

cgroup: initialize cgrp_dfl_root_inhibit_ss_mask from !->dfl_files test

2014-07-15T15:05:10Z

cgrp_dfl_root_inhibit_ss_mask determines which subsystems are not supported on the default hierarchy and is currently initialized statically and just includes the debug subsystem. Now that there's cgroup_subsys->dfl_files, we can easily tell which subsystems support the default hierarchy or not. Let's initialize cgrp_dfl_root_inhibit_ss_mask by testing whether cgroup_subsys->dfl_files is NULL. After all, subsystems with NULL ->dfl_files aren't useable on the default hierarchy anyway. Signed-off-by: Tejun Heo Acked-by: Li Zefan

cgroup: make CFTYPE_ONLY_ON_DFL and CFTYPE_NO_ internal to cgroup core

2014-07-15T15:05:10Z

cgroup now distinguishes cftypes for the default and legacy hierarchies more explicitly by using separate arrays and CFTYPE_ONLY_ON_DFL and CFTYPE_INSANE should be and are used only inside cgroup core proper. Let's make it clear that the flags are internal by prefixing them with double underscores. CFTYPE_INSANE is renamed to __CFTYPE_NOT_ON_DFL for consistency. The two flags are also collected and assigned bits >= 16 so that they aren't mixed with the published flags. v2: Convert the extra ones in cgroup_exit_cftypes() which are added by revision to the previous patch. Signed-off-by: Tejun Heo Acked-by: Li Zefan

cgroup: distinguish the default and legacy hierarchies when handling cftypes

2014-07-15T15:05:10Z

Until now, cftype arrays carried files for both the default and legacy hierarchies and the files which needed to be used on only one of them were flagged with either CFTYPE_ONLY_ON_DFL or CFTYPE_INSANE. This gets confusing very quickly and we may end up exposing interface files to the default hierarchy without thinking it through. This patch makes cgroup core provide separate sets of interfaces for cftype handling so that the cftypes for the default and legacy hierarchies are clearly distinguished. The previous two patches renamed the existing ones so that they clearly indicate that they're for the legacy hierarchies. This patch adds the interface for the default hierarchy and apply them selectively depending on the hierarchy type. * cftypes added through cgroup_subsys->dfl_cftypes and cgroup_add_dfl_cftypes() only show up on the default hierarchy. * cftypes added through cgroup_subsys->legacy_cftypes and cgroup_add_legacy_cftypes() only show up on the legacy hierarchies. * cgroup_subsys->dfl_cftypes and ->legacy_cftypes can point to the same array for the cases where the interface files are identical on both types of hierarchies. * This makes all the existing subsystem interface files legacy-only by default and all subsystems will have no interface file created when enabled on the default hierarchy. Each subsystem should explicitly review and compose the interface for the default hierarchy. * A boot param "cgroup__DEVEL__legacy_files_on_dfl" is added which makes subsystems which haven't decided the interface files for the default hierarchy to present the legacy files on the default hierarchy so that its behavior on the default hierarchy can be tested. As the awkward name suggests, this is for development only. * memcg's CFTYPE_INSANE on "use_hierarchy" is noop now as the whole array isn't used on the default hierarchy. The flag is removed. v2: Updated documentation for cgroup__DEVEL__legacy_files_on_dfl. v3: Clear CFTYPE_ONLY_ON_DFL and CFTYPE_INSANE when cfts are removed as suggested by Li. Signed-off-by: Tejun Heo Acked-by: Neil Horman Acked-by: Li Zefan Cc: Johannes Weiner Cc: Michal Hocko Cc: Vivek Goyal Cc: Peter Zijlstra Cc: Paul Mackerras Cc: Ingo Molnar Cc: Arnaldo Carvalho de Melo Cc: Aristeu Rozanski Cc: Aneesh Kumar K.V

cgroup: replace cgroup_add_cftypes() with cgroup_add_legacy_cftypes()

2014-07-15T15:05:09Z

Currently, cftypes added by cgroup_add_cftypes() are used for both the unified default hierarchy and legacy ones and subsystems can mark each file with either CFTYPE_ONLY_ON_DFL or CFTYPE_INSANE if it has to appear only on one of them. This is quite hairy and error-prone. Also, we may end up exposing interface files to the default hierarchy without thinking it through. cgroup_subsys will grow two separate cftype addition functions and apply each only on the hierarchies of the matching type. This will allow organizing cftypes in a lot clearer way and encourage subsystems to scrutinize the interface which is being exposed in the new default hierarchy. In preparation, this patch adds cgroup_add_legacy_cftypes() which currently is a simple wrapper around cgroup_add_cftypes() and replaces all cgroup_add_cftypes() usages with it. While at it, this patch drops a completely spurious return from __hugetlb_cgroup_file_init(). This patch doesn't introduce any functional differences. Signed-off-by: Tejun Heo Acked-by: Neil Horman Acked-by: Li Zefan Cc: Johannes Weiner Cc: Michal Hocko Cc: Aneesh Kumar K.V

cgroup: rename cgroup_subsys->base_cftypes to ->legacy_cftypes

2014-07-15T15:05:09Z

Currently, cgroup_subsys->base_cftypes is used for both the unified default hierarchy and legacy ones and subsystems can mark each file with either CFTYPE_ONLY_ON_DFL or CFTYPE_INSANE if it has to appear only on one of them. This is quite hairy and error-prone. Also, we may end up exposing interface files to the default hierarchy without thinking it through. cgroup_subsys will grow two separate cftype arrays and apply each only on the hierarchies of the matching type. This will allow organizing cftypes in a lot clearer way and encourage subsystems to scrutinize the interface which is being exposed in the new default hierarchy. In preparation, this patch renames cgroup_subsys->base_cftypes to cgroup_subsys->legacy_cftypes. This patch is pure rename. Signed-off-by: Tejun Heo Acked-by: Neil Horman Acked-by: Li Zefan Cc: Johannes Weiner Cc: Michal Hocko Cc: Vivek Goyal Cc: Peter Zijlstra Cc: Paul Mackerras Cc: Ingo Molnar Cc: Arnaldo Carvalho de Melo Cc: Aristeu Rozanski Cc: Aneesh Kumar K.V

cgroup: split cgroup_base_files[] into cgroup_{dfl|legacy}_base_files[]

2014-07-15T15:05:09Z

Currently cgroup_base_files[] contains the cgroup core interface files for both legacy and default hierarchies with each file tagged with CFTYPE_INSANE and CFTYPE_ONLY_ON_DFL. This is difficult to read. Let's separate it out to two separate tables, cgroup_dfl_base_files[] and cgroup_legacy_base_files[], and use the appropriate one in cgroup_mkdir() depending on the hierarchy type. This makes tagging each file unnecessary. This patch doesn't introduce any behavior changes. v2: cgroup_dfl_base_files[] was missing the termination entry triggering WARN in cgroup_init_cftypes() for 0day kernel testing robot. Fixed. Signed-off-by: Tejun Heo Acked-by: Li Zefan Cc: Jet Chen

cgroup: clean up sane_behavior handling

2014-07-09T14:08:08Z

After the previous patch to remove sane_behavior support from non-default hierarchies, CGRP_ROOT_SANE_BEHAVIOR is used only to indicate the default hierarchy while parsing mount options. This patch makes the following cleanups around it. * Don't show it in the mount option. Eventually the default hierarchy will be assigned a different filesystem type. * As sane_behavior is no longer effective on non-default hierarchies and the default hierarchy doesn't accept any mount options, parse_cgroupfs_options() can consider sane_behavior mount option as indicating the default hierarchy and fail if any other options are specified with it. While at it, remove one of the double blank lines in the function. * cgroup_mount() can now simply test CGRP_ROOT_SANE_BEHAVIOR to tell whether to mount the default hierarchy or not. * As CGROUP_ROOT_SANE_BEHAVIOR's only role now is indicating whether to select the default hierarchy or not during mount, it doesn't need to be set in the default hierarchy itself. cgroup_init_early() updated accordingly. Signed-off-by: Tejun Heo Acked-by: Li Zefan

cgroup: remove sane_behavior support on non-default hierarchies

2014-07-09T14:08:08Z

sane_behavior has been used as a development vehicle for the default unified hierarchy. Now that the default hierarchy is in place, the flag became redundant and confusing as its usage is allowed on all hierarchies. There are gonna be either the default hierarchy or legacy ones. Let's make that clear by removing sane_behavior support on non-default hierarchies. This patch replaces cgroup_sane_behavior() with cgroup_on_dfl(). The comment on top of CGRP_ROOT_SANE_BEHAVIOR is moved to on top of cgroup_on_dfl() with sane_behavior specific part dropped. On the default and legacy hierarchies w/o sane_behavior, this shouldn't cause any behavior differences. Signed-off-by: Tejun Heo Acked-by: Vivek Goyal Acked-by: Li Zefan Cc: Johannes Weiner Cc: Michal Hocko