07 Aug, 2013
1 commit
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Pull cgroup fix from Tejun Heo:
"Fix for a minor memory leak bug in the cgroup init failure path"* 'for-3.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: fix a leak when percpu_ref_init() fails
31 Jul, 2013
1 commit
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ss->css_free() is not called when perfcpu_ref_init() fails.
Signed-off-by: Li Zefan
Signed-off-by: Tejun Heo
24 Jul, 2013
1 commit
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Pull cgroup changes from Tejun Heo:
"This contains two patches, both of which aren't fixes per-se but I
think it'd be better to fast-track them.One removes bcache_subsys_id which was added without proper review
through the block tree. Fortunately, bcache cgroup code is
unconditionally disabled, so this was never exposed to userland. The
cgroup subsys_id is removed. Kent will remove the affected (disabled)
code through bcache branch.The other simplifies task_group_path_from_hierarchy(). The function
doesn't currently have in-kernel users but there are external code and
development going on dependent on the function and making the function
available for 3.11 would make things go smoother"* 'for-3.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: replace task_cgroup_path_from_hierarchy() with task_cgroup_path()
cgroup: remove bcache_subsys_id which got added stealthily
14 Jul, 2013
1 commit
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Signed-off-by: Al Viro
13 Jul, 2013
1 commit
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task_cgroup_path_from_hierarchy() was added for the planned new users
and none of the currently planned users wants to know about multiple
hierarchies. This patch drops the multiple hierarchy part and makes
it always return the path in the first non-dummy hierarchy.As unified hierarchy will always have id 1, this is guaranteed to
return the path for the unified hierarchy if mounted; otherwise, it
will return the path from the hierarchy which happens to occupy the
lowest hierarchy id, which will usually be the first hierarchy mounted
after boot.Signed-off-by: Tejun Heo
Acked-by: Li Zefan
Cc: Lennart Poettering
Cc: Kay Sievers
Cc: Jan Kaluža
30 Jun, 2013
1 commit
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0ce6cba357 ("cgroup: CGRP_ROOT_SUBSYS_BOUND should be ignored when
comparing mount options") only updated the remount path but
CGRP_ROOT_SUBSYS_BOUND should also be ignored when comparing options
while mounting an existing hierarchy. As option mismatch triggers a
warning but doesn't fail the mount without sane_behavior, this only
triggers a spurious warning message.Fix it by only comparing CGRP_ROOT_OPTION_MASK bits when comparing new
and existing root options.Signed-off-by: Tejun Heo
28 Jun, 2013
2 commits
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1672d04070 ("cgroup: fix cgroupfs_root early destruction path")
introduced CGRP_ROOT_SUBSYS_BOUND which is used to mark completion of
subsys binding on a new root; however, this broke remounts.
cgroup_remount() doesn't allow changing root options via remount and
CGRP_ROOT_SUBSYS_BOUND, which is set on all fully initialized roots,
makes the function reject all remounts.Fix it by putting the options part in the lower 16 bits of root->flags
and masking the comparions. While at it, make cgroup_remount() emit
an error message explaining why it's rejecting a remount request, so
that it's less of a mystery.Signed-off-by: Tejun Heo
-
eb178d06332 ("cgroup: grab cgroup_mutex in
drop_parsed_module_refcounts()") made drop_parsed_module_refcounts()
grab cgroup_mutex to make lockdep assertion in for_each_subsys()
happy. Unfortunately, cgroup_remount() calls the function while
holding cgroup_mutex in its failure path leading to the following
deadlock.# mount -t cgroup -o remount,memory,blkio cgroup blkio
cgroup: option changes via remount are deprecated (pid=525 comm=mount)
=============================================
[ INFO: possible recursive locking detected ]
3.10.0-rc4-work+ #1 Not tainted
---------------------------------------------
mount/525 is trying to acquire lock:
(cgroup_mutex){+.+.+.}, at: [] drop_parsed_module_refcounts+0x21/0xb0but task is already holding lock:
(cgroup_mutex){+.+.+.}, at: [] cgroup_remount+0x51/0x200other info that might help us debug this:
Possible unsafe locking scenario:CPU0
----
lock(cgroup_mutex);
lock(cgroup_mutex);*** DEADLOCK ***
May be due to missing lock nesting notation
4 locks held by mount/525:
#0: (&type->s_umount_key#30){+.+...}, at: [] do_mount+0x2bd/0xa30
#1: (&sb->s_type->i_mutex_key#9){+.+.+.}, at: [] cgroup_remount+0x43/0x200
#2: (cgroup_mutex){+.+.+.}, at: [] cgroup_remount+0x51/0x200
#3: (cgroup_root_mutex){+.+.+.}, at: [] cgroup_remount+0x5f/0x200stack backtrace:
CPU: 2 PID: 525 Comm: mount Not tainted 3.10.0-rc4-work+ #1
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
ffffffff829651f0 ffff88000ec2fc28 ffffffff81c24bb1 ffff88000ec2fce8
ffffffff810f420d 0000000000000006 0000000000000001 0000000000000056
ffff8800153b4640 ffff880000000000 ffffffff81c2e468 ffff8800153b4640
Call Trace:
[] dump_stack+0x19/0x1b
[] __lock_acquire+0x15dd/0x1e60
[] lock_acquire+0x9c/0x1f0
[] mutex_lock_nested+0x65/0x410
[] drop_parsed_module_refcounts+0x21/0xb0
[] cgroup_remount+0x1ae/0x200
[] do_remount_sb+0x82/0x190
[] do_mount+0x5f1/0xa30
[] SyS_mount+0x83/0xc0
[] system_call_fastpath+0x16/0x1bFix it by moving the drop_parsed_module_refcounts() invocation outside
cgroup_mutex.Signed-off-by: Tejun Heo
27 Jun, 2013
4 commits
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kernel/cgroup.c still has places where a RCU pointer is set and
accessed directly without going through RCU_INIT_POINTER() or
rcu_dereference_protected(). They're all properly protected accesses
so nothing is broken but it leads to spurious sparse RCU address space
warnings.Substitute direct accesses with RCU_INIT_POINTER() and
rcu_dereference_protected(). Note that %true is specified as the
extra condition for all derference updates. This isn't ideal as all
it does is suppressing warning without actually policing
synchronization rules; however, most are scheduled to be removed
pretty soon along with css_id itself, so no reason to be more
elaborate.Combined with the previous changes, this removes all RCU related
sparse warnings from cgroup.Signed-off-by: Tejun Heo
Reported-by: Fengguang Wu
Acked-by; Li Zefan -
There are several places in kernel/cgroup.c where task->cgroups is
accessed and modified without going through proper RCU accessors.
None is broken as they're all lock protected accesses; however, this
still triggers sparse RCU address space warnings.* Consistently use task_css_set() for task->cgroups dereferencing.
* Use RCU_INIT_POINTER() to clear task->cgroups to &init_css_set on
exit.* Remove unnecessary rcu_dereference_raw() from cset->subsys[]
dereference in cgroup_exit().Signed-off-by: Tejun Heo
Reported-by: Fengguang Wu
Acked-by: Li Zefan -
This isn't strictly necessary as all subsystems specified in
@subsys_mask are guaranteed to be pinned; however, it does spuriously
trigger lockdep warning. Let's grab cgroup_mutex around it.Signed-off-by: Tejun Heo
Acked-by: Li Zefan -
cgroupfs_root used to have ->actual_subsys_mask in addition to
->subsys_mask. a8a648c4ac ("cgroup: remove
cgroup->actual_subsys_mask") removed it noting that the subsys_mask is
essentially temporary and doesn't belong in cgroupfs_root; however,
the patch made it impossible to tell whether a cgroupfs_root actually
has the subsystems bound or just have the bits set leading to the
following BUG when trying to mount with subsystems which are already
mounted elsewhere.kernel BUG at kernel/cgroup.c:1038!
invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
...
CPU: 1 PID: 7973 Comm: mount Tainted: G W 3.10.0-rc7-next-20130625-sasha-00011-g1c1dc0e #1105
task: ffff880fc0ae8000 ti: ffff880fc0b9a000 task.ti: ffff880fc0b9a000
RIP: 0010:[] [] rebind_subsystems+0x409/0x5f0
...
Call Trace:
[] cgroup_kill_sb+0xff/0x210
[] deactivate_locked_super+0x4f/0x90
[] cgroup_mount+0x673/0x6e0
[] cpuset_mount+0xd9/0x110
[] mount_fs+0xb0/0x2d0
[] vfs_kern_mount+0xbd/0x180
[] do_new_mount+0x145/0x2c0
[] do_mount+0x356/0x3c0
[] SyS_mount+0xfd/0x140
[] tracesys+0xdd/0xe2We still want rebind_subsystems() to take added/removed masks, so
let's fix it by marking whether a cgroupfs_root has finished binding
or not. Also, document what's going on around ->subsys_mask
initialization so that similar mistakes aren't repeated.Signed-off-by: Tejun Heo
Reported-by: Sasha Levin
Acked-by: Li Zefan
26 Jun, 2013
3 commits
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Before 1a57423166 ("cgroup: make hierarchy_id use cyclic idr"),
hierarchy IDs were allocated from 0. As the dummy hierarchy was
always the one first initialized, it got assigned 0 and all other
hierarchies from 1. The patch accidentally changed the minimum
useable ID to 2.Let's restore ID 0 for dummy_root and while at it reserve 1 for
unified hierarchy.Signed-off-by: Tejun Heo
Acked-by: Li Zefan
Cc: stable@vger.kernel.org -
There are quite a few places where all loaded [builtin] subsys are
iterated. Implement for_each_[builtin_]subsys() and replace manual
iterations with those to simplify those places a bit. The new
iterators automatically skip NULL subsystems. This shouldn't cause
any functional difference.Iteration loops which scan all subsystems and then skipping modular
ones explicitly are converted to use for_each_builtin_subsys().While at it, reorder variable declarations and adjust whitespaces a
bit in the affected functions.v2: Add lockdep_assert_held() in for_each_subsys() and add comments
about synchronization as suggested by Li.Signed-off-by: Tejun Heo
Acked-by: Li Zefan -
cgroup_init() was doing init_css_set initialization outside
cgroup_mutex, which is fine but we want to add lockdep annotation on
subsystem iterations and cgroup_init() will trigger it spuriously.
Move init_css_set initialization inside cgroup_mutex.Signed-off-by: Tejun Heo
Acked-by: Li Zefan
25 Jun, 2013
4 commits
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for_each_subsys() walks over subsystems attached to a hierarchy and
we're gonna add iterators which walk over all available subsystems.
Rename for_each_subsys() to for_each_root_subsys() so that it's more
appropriately named and for_each_subsys() can be used to iterate all
subsystems.While at it, remove unnecessary underbar prefix from macro arguments,
put them inside parentheses, and adjust indentation for the two
for_each_*() macros.This patch is purely cosmetic.
Signed-off-by: Tejun Heo
Acked-by: Li Zefan -
find_css_set() passes uninitialized on-stack template[] array to
find_existing_css_set() which sets the entries for all subsystems.
Passing around an uninitialized array is a bit icky and we want to
introduce an iterator which only iterates loaded subsystems. Let's
initialize it on definition.While at it, also make the following cosmetic cleanups.
* Convert to proper /** comments.
* Reorder variable declarations.
* Replace comment on synchronization with lockdep_assert_held().
This patch doesn't make any functional differences.
Signed-off-by: Tejun Heo
Acked-by: Li Zefan -
cgroup curiously has two subsystem masks, ->subsys_mask and
->actual_subsys_mask. The latter only exists because the new target
subsys_mask is passed into rebind_subsystems() via @root>subsys_mask.
rebind_subsystems() needs to know what the current mask is to decide
how to reach the target mask so ->actual_subsys_mask is used as the
temp location to remember the current state.Adding a temporary field to a permanent data structure is rather silly
and can be misleading. Update rebind_subsystems() to take @added_mask
and @removed_mask instead and remove @root->actual_subsys_mask.This patch shouldn't introduce any behavior changes.
v2: Comment and description updated as suggested by Li.
Signed-off-by: Tejun Heo
Acked-by: Li Zefan -
Global variable names in kernel/cgroup.c are asking for trouble -
subsys, roots, rootnode and so on. Rename them to have "cgroup_"
prefix.* s/subsys/cgroup_subsys/
* s/rootnode/cgroup_dummy_root/
* s/dummytop/cgroup_cummy_top/
* s/roots/cgroup_roots/
* s/root_count/cgroup_root_count/
This patch is purely cosmetic.
Signed-off-by: Tejun Heo
Acked-by: Li Zefan
19 Jun, 2013
7 commits
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Cont is short for container. control group was named process container
at first, but then people found container already has a meaning in
linux kernel.Clean up the leftover variable name @cont.
Signed-off-by: Li Zefan
Signed-off-by: Tejun Heo -
cgroup_serial_nr_cursor was created atomic64_t because I thought it
was never gonna used for anything other than assigning unique numbers
to cgroups and didn't want to worry about synchronization; however,
now we're using it as an event-stamp to distinguish cgroups created
before and after certain point which assumes that it's protected by
cgroup_mutex.Let's make it clear by making it a u64. Also, rename it to
cgroup_serial_nr_next and make it point to the next nr to allocate so
that where it's pointing to is clear and more conventional.Signed-off-by: Tejun Heo
Cc: Li Zefan -
We used root->allcg_list to iterate cgroup hierarchy because at that time
cgroup_for_each_descendant_pre() hasn't been invented.tj: In cgroup_cfts_commit(), s/@serial_nr/@update_upto/, move the
assignment right above releasing cgroup_mutex and explain what's
going on there.Signed-off-by: Li Zefan
Signed-off-by: Tejun Heo -
The next patch will use it to determine if a cgroup is newly created
while we're iterating the cgroup hierarchy.tj: Rephrased the comment on top of cgroup_serial_nr_cursor.
Signed-off-by: Li Zefan
Signed-off-by: Tejun Heo -
The memory allocated in cgroup_add_cftypes() should be freed. The
effect of this bug is we leak a bit memory everytime we unload
cfq-iosched module if blkio cgroup is enabled.Signed-off-by: Li Zefan
Signed-off-by: Tejun Heo -
commit 5db9a4d99b0157a513944e9a44d29c9cec2e91dc
Author: Tejun Heo
Date: Sat Jul 7 16:08:18 2012 -0700cgroup: fix cgroup hierarchy umount race
This commit fixed a race caused by the dput() in css_dput_fn(), but
the dput() in cgroup_event_remove() can also lead to the same BUG().Signed-off-by: Li Zefan
Signed-off-by: Tejun Heo
Cc: stable@vger.kernel.org -
cgroup_cfts_commit() uses dget() to keep cgroup alive after cgroup_mutex
is dropped, but dget() won't prevent cgroupfs from being umounted. When
the race happens, vfs will see some dentries with non-zero refcnt while
umount is in process.Keep running this:
mount -t cgroup -o blkio xxx /cgroup
umount /cgroupAnd this:
modprobe cfq-iosched
rmmod cfs-ioschedAfter a while, the BUG() in shrink_dcache_for_umount_subtree() may
be triggered:BUG: Dentry xxx{i=0,n=blkio.yyy} still in use (1) [umount of cgroup cgroup]
Signed-off-by: Li Zefan
Signed-off-by: Tejun Heo
Cc: stable@vger.kernel.org
18 Jun, 2013
1 commit
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cgroup's rename(2) isn't a proper migration implementation - it can't
move the cgroup to a different parent in the hierarchy. All it can do
is swapping the name string for that cgroup. This isn't useful and
can mislead users to think that cgroup supports proper cgroup-level
migration. Disallow rename(2) if sane_behavior.v2: Fail with -EPERM instead of -EINVAL so that it matches the vfs
return value when ->rename is not implemented as suggested by Li.Signed-off-by: Tejun Heo
Acked-by: Li Zefan
14 Jun, 2013
11 commits
-
A css (cgroup_subsys_state) is how each cgroup is represented to a
controller. As such, it can be used in hot paths across the various
subsystems different controllers are associated with.One of the common operations is reference counting, which up until now
has been implemented using a global atomic counter and can have
significant adverse impact on scalability. For example, css refcnt
can be gotten and put multiple times by blkcg for each IO request.
For highops configurations which try to do as much per-cpu as
possible, the global frequent refcnting can be very expensive.In general, given the various and hugely diverse paths css's end up
being used from, we need to make it cheap and highly scalable. In its
usage, css refcnting isn't very different from module refcnting.This patch converts css refcnting to use the recently added
percpu_ref. css_get/tryget/put() directly maps to the matching
percpu_ref operations and the deactivation logic is no longer
necessary as percpu_ref already has refcnt killing.The only complication is that as the refcnt is per-cpu,
percpu_ref_kill() in itself doesn't ensure that further tryget
operations will fail, which we need to guarantee before invoking
->css_offline()'s. This is resolved collecting kill confirmation
using percpu_ref_kill_and_confirm() and initiating the offline phase
of destruction after all css refcnt's are confirmed to be seen as
killed on all CPUs. The previous patches already splitted destruction
into two phases, so percpu_ref_kill_and_confirm() can be hooked up
easily.This patch removes css_refcnt() which is used for rcu dereference
sanity check in css_id(). While we can add a percpu refcnt API to ask
the same question, css_id() itself is scheduled to be removed fairly
soon, so let's not bother with it. Just drop the sanity check and use
rcu_dereference_raw() instead.v2: - init_cgroup_css() was calling percpu_ref_init() without checking
the return value. This causes two problems - the obvious lack
of error handling and percpu_ref_init() being called from
cgroup_init_subsys() before the allocators are up, which
triggers warnings but doesn't cause actual problems as the
refcnt isn't used for roots anyway. Fix both by moving
percpu_ref_init() to cgroup_create().- The base references were put too early by
percpu_ref_kill_and_confirm() and cgroup_offline_fn() put the
refs one extra time. This wasn't noticeable because css's go
through another RCU grace period before being freed. Update
cgroup_destroy_locked() to grab an extra reference before
killing the refcnts. This problem was noticed by Kent.Signed-off-by: Tejun Heo
Reviewed-by: Kent Overstreet
Acked-by: Li Zefan
Cc: Michal Hocko
Cc: Mike Snitzer
Cc: Vivek Goyal
Cc: "Alasdair G. Kergon"
Cc: Jens Axboe
Cc: Mikulas Patocka
Cc: Glauber Costa -
This is to receive percpu_refcount which will replace atomic_t
reference count in cgroup_subsys_state.Signed-off-by: Tejun Heo
-
Split cgroup_destroy_locked() into two steps and put the latter half
into cgroup_offline_fn() which is executed from a work item. The
latter half is responsible for offlining the css's, removing the
cgroup from internal lists, and propagating release notification to
the parent. The separation is to allow using percpu refcnt for css.Note that this allows for other cgroup operations to happen between
the first and second halves of destruction, including creating a new
cgroup with the same name. As the target cgroup is marked DEAD in the
first half and cgroup internals don't care about the names of cgroups,
this should be fine. A comment explaining this will be added by the
next patch which implements the actual percpu refcnting.As RCU freeing is guaranteed to happen after the second step of
destruction, we can use the same work item for both. This patch
renames cgroup->free_work to ->destroy_work and uses it for both
purposes. INIT_WORK() is now performed right before queueing the work
item.Signed-off-by: Tejun Heo
Acked-by: Li Zefan -
This patch reorders the operations in cgroup_destroy_locked() such
that the userland visible parts happen before css offlining and
removal from the ->sibling list. This will be used to make css use
percpu refcnt.While at it, split out CGRP_DEAD related comment from the refcnt
deactivation one and correct / clarify how different guarantees are
met.While this patch changes the specific order of operations, it
shouldn't cause any noticeable behavior difference.Signed-off-by: Tejun Heo
Acked-by: Li Zefan -
cgroup->count tracks the number of css_sets associated with the cgroup
and used only to verify that no css_set is associated when the cgroup
is being destroyed. It's superflous as the destruction path can
simply check whether cgroup->cset_links is empty instead.Drop cgroup->count and check ->cset_links directly from
cgroup_destroy_locked().Signed-off-by: Tejun Heo
Acked-by: Li Zefan -
__put_css_set() does RCU read access on @cgrp across dropping
@cgrp->count so that it can continue accessing @cgrp even if the count
reached zero and destruction of the cgroup commenced. Given that both
sides - __css_put() and cgroup_destroy_locked() - are cold paths, this
is unnecessary. Just making cgroup_destroy_locked() grab css_set_lock
while checking @cgrp->count is enough.Remove the RCU read locking from __put_css_set() and make
cgroup_destroy_locked() read-lock css_set_lock when checking
@cgrp->count. This will also allow removing @cgrp->count.Signed-off-by: Tejun Heo
Acked-by: Li Zefan -
We will add another flag indicating that the cgroup is in the process
of being killed. REMOVING / REMOVED is more difficult to distinguish
and cgroup_is_removing()/cgroup_is_removed() are a bit awkward. Also,
later percpu_ref usage will involve "kill"ing the refcnt.s/CGRP_REMOVED/CGRP_DEAD/
s/cgroup_is_removed()/cgroup_is_dead()This patch is purely cosmetic.
Signed-off-by: Tejun Heo
Acked-by: Li Zefan -
There's no point in using kmalloc() instead of the clearing variant
for trivial stuff. We can live dangerously elsewhere. Use kzalloc()
instead and drop 0 inits.While at it, do trivial code reorganization in cgroup_file_open().
This patch doesn't introduce any functional changes.
v2: I was caught in the very distant past where list_del() didn't
poison and the initial version converted list_del()s to
list_del_init()s too. Li and Kent took me out of the stasis
chamber.Signed-off-by: Tejun Heo
Cc: Kent Overstreet
Acked-by: Li Zefan -
cgroups and css_sets are mapped M:N and this M:N mapping is
represented by struct cg_cgroup_link which forms linked lists on both
sides. The naming around this mapping is already confusing and struct
cg_cgroup_link exacerbates the situation quite a bit.>From cgroup side, it starts off ->css_sets and runs through
->cgrp_link_list. From css_set side, it starts off ->cg_links and
runs through ->cg_link_list. This is rather reversed as
cgrp_link_list is used to iterate css_sets and cg_link_list cgroups.
Also, this is the only place which is still using the confusing "cg"
for css_sets. This patch cleans it up a bit.* s/cgroup->css_sets/cgroup->cset_links/
s/css_set->cg_links/css_set->cgrp_links/
s/cgroup_iter->cg_link/cgroup_iter->cset_link/* s/cg_cgroup_link/cgrp_cset_link/
* s/cgrp_cset_link->cg/cgrp_cset_link->cset/
s/cgrp_cset_link->cgrp_link_list/cgrp_cset_link->cset_link/
s/cgrp_cset_link->cg_link_list/cgrp_cset_link->cgrp_link/* s/init_css_set_link/init_cgrp_cset_link/
s/free_cg_links/free_cgrp_cset_links/
s/allocate_cg_links/allocate_cgrp_cset_links/* s/cgl[12]/link[12]/ in compare_css_sets()
* s/saved_link/tmp_link/ s/tmp/tmp_links/ and a couple similar
adustments.* Comment and whiteline adjustments.
After the changes, we have
list_for_each_entry(link, &cont->cset_links, cset_link) {
struct css_set *cset = link->cset;instead of
list_for_each_entry(link, &cont->css_sets, cgrp_link_list) {
struct css_set *cset = link->cg;This patch is purely cosmetic.
v2: Fix broken sentences in the patch description.
Signed-off-by: Tejun Heo
Acked-by: Li Zefan -
cgroup.c uses @cg for most struct css_set variables, which in itself
could be a bit confusing, but made much worse by the fact that there
are places which use @cg for struct cgroup variables.
compare_css_sets() epitomizes this confusion - @[old_]cg are struct
css_set while @cg[12] are struct cgroup.It's not like the whole deal with cgroup, css_set and cg_cgroup_link
isn't already confusing enough. Let's give it some sanity by
uniformly using @cset for all struct css_set variables.* s/cg/cset/ for all css_set variables.
* s/oldcg/old_cset/ s/oldcgrp/old_cgrp/. The same for the ones
prefixed with "new".* s/cg/cgrp/ for cgroup variables in compare_css_sets().
* s/css/cset/ for the cgroup variable in task_cgroup_from_root().
* Whiteline adjustments.
This patch is purely cosmetic.
Signed-off-by: Tejun Heo
Acked-by: Li Zefan -
Signed-off-by: Tejun Heo
Acked-by: Li Zefan
06 Jun, 2013
2 commits
-
* Rename it from files[] (really?) to cgroup_base_files[].
* Drop CGROUP_FILE_GENERIC_PREFIX which was defined as "cgroup." and
used inconsistently. Just use "cgroup." directly.* Collect insane files at the end. Note that only the insane ones are
missing "cgroup." prefix.This patch doesn't introduce any functional changes.
Signed-off-by: Tejun Heo
Acked-by: Li Zefan -
The empty cgroup notification mechanism currently implemented in
cgroup is tragically outdated. Forking and execing userland process
stopped being a viable notification mechanism more than a decade ago.
We're gonna have a saner mechanism. Let's make it clear that this
abomination is going away.Mark "notify_on_release" and "release_agent" with CFTYPE_INSANE.
Signed-off-by: Tejun Heo
Acked-by: Li Zefan