[PATCHSET] cgroup: cftype based file interface, take #2

[PATCHSET] cgroup: cftype based file interface, take #2

[Tejun Heo]

Hello,

This is the second take at improving cgroup file addition/removal
interface.  Changes from the last take[L] are,

* CGROUP_SUBSYS_CFTYPES[_COND]() dropped and
  cgroup_subsys->base_cftypes is added instead.  This works better for
  subsystems implemented as module.  tcp_memcontrol now uses an
  explicit __initcall() to register its cftypes.

* 0005-cgroup-relocate-cftype-and-cgroup_subsys-definitions.patch
  added as cleanup.

* 0007-memcg-always-create-memsw-files-if-CONFIG_CGROUP_MEM.patch
  added so that memsw files are always created if enabled in config as
  suggested by KAMEZAWA.

This patch replaces cgroup file interface with cftype based one which
allows dynamic additions and removals of cftype arrays whether the
target subsystem is attached or not.  This can be used to make subsys
rebinding via remount work properly but I intentionally avoided doing
that at the moment.

This makes cgroup population simpler for controllers and will be used
to allow controllers to be more dynamic.  e.g. blkio subsys has
sub-policies which may come and go while blkio subsys is attached and
it currently uses fixed set of files which stays blank if not in use.
This will also be useful for implementing unified hierarchy.

This patchset contains the following patches.

 0001-cgroup-move-cgroup_clear_directory-call-out-of-cgrou.patch
 0002-cgroup-build-list-of-all-cgroups-under-a-given-cgrou.patch
 0003-cgroup-implement-cgroup_add_cftypes-and-friends.patch
 0004-cgroup-merge-cft_release_agent-cftype-array-into-the.patch
 0005-cgroup-relocate-cftype-and-cgroup_subsys-definitions.patch
 0006-cgroup-convert-all-non-memcg-controllers-to-the-new-.patch
 0007-memcg-always-create-memsw-files-if-CONFIG_CGROUP_MEM.patch
 0008-cgroup-convert-memcg-controller-to-the-new-cftype-in.patch
 0009-cgroup-remove-cgroup_add_file-s.patch
 0010-cgroup-relocate-__d_cgrp-and-__d_cft.patch
 0011-cgroup-introduce-struct-cfent.patch
 0012-cgroup-implement-cgroup_rm_cftypes.patch

and is on top of

  cgroup/for-3.4 3ce3230a0cff484e5130153f244d4fb8a56b3a8b
+ [1] cgroup: deprecate remount option changes mount option

and is also available in the following git branch.

 git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc.git cgroup-cftype

Glauber, I think the cftypes registration for tcp_memcontrol is fine
as is in this patchset and we just need to move the init to the tail
of ->create().  Let's worry about memcg for module-loadable protocols
whey they are added.  Can you please send a patch to move init to
->create()?

If nobody objects && after Li comes back and acks the changes, I'll
route these through cgroup/for-3.5.

diffstat follows.

 block/blk-cgroup.c        |   45 ++---
 include/linux/cgroup.h    |   51 ++++--
 kernel/cgroup.c           |  359 +++++++++++++++++++++++++++++++++++-----------
 kernel/cgroup_freezer.c   |   11 -
 kernel/cpuset.c           |   31 +--
 kernel/sched/core.c       |   16 --
 mm/memcontrol.c           |   77 ++++-----
 net/core/netprio_cgroup.c |   30 +--
 net/ipv4/tcp_memcontrol.c |   71 ++++-----
 net/sched/cls_cgroup.c    |   31 +--
 security/device_cgroup.c  |   10 -
 11 files changed, 437 insertions(+), 295 deletions(-)

Thanks.

--
tejun

[L] http://thread.gmane.org/gmane.linux.kernel.containers/22623
[1] http://thread.gmane.org/gmane.linux.kernel.cgroups/1192/focus=22611

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Glauber Costa]

On 04/03/2012 10:52 PM, Tejun Heo wrote:
> On Tue, Apr 03, 2012 at 11:47:19AM -0700, Tejun Heo wrote:
>> Hello, Glauber.
>>
>> On Tue, Apr 03, 2012 at 07:22:59AM +0400, Glauber Costa wrote:
>>> Do I need to send you a patch to remove memcg's populate on top of this ?
>>
>> populate is already gone.  My memory is a bit fuzzy now.  Can you spot
>> something broken / to be improved re. memcg cftypes in the current
>> cgroup/for-3.5 branch?
>
> Ugh... brainfart.  Please disregard the previous message.  Can you
> please resend the patches on top of cgroup/for-3.5 and use Li's new
> address - lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org ?
>
> Thanks.
>
All right.
I'll give a new test to make sure it is still okay, and send shortly

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Glauber Costa]

On 04/03/2012 10:52 PM, Tejun Heo wrote:
> On Tue, Apr 03, 2012 at 11:47:19AM -0700, Tejun Heo wrote:
>> Hello, Glauber.
>>
>> On Tue, Apr 03, 2012 at 07:22:59AM +0400, Glauber Costa wrote:
>>> Do I need to send you a patch to remove memcg's populate on top of this ?
>>
>> populate is already gone.  My memory is a bit fuzzy now.  Can you spot
>> something broken / to be improved re. memcg cftypes in the current
>> cgroup/for-3.5 branch?
>
> Ugh... brainfart.  Please disregard the previous message.  Can you
> please resend the patches on top of cgroup/for-3.5 and use Li's new
> address - lizefan@huawei.com ?
>
> Thanks.
>
All right.
I'll give a new test to make sure it is still okay, and send shortly

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Glauber Costa]

On 04/03/2012 10:52 PM, Tejun Heo wrote:
> On Tue, Apr 03, 2012 at 11:47:19AM -0700, Tejun Heo wrote:
>> Hello, Glauber.
>>
>> On Tue, Apr 03, 2012 at 07:22:59AM +0400, Glauber Costa wrote:
>>> Do I need to send you a patch to remove memcg's populate on top of this ?
>>
>> populate is already gone.  My memory is a bit fuzzy now.  Can you spot
>> something broken / to be improved re. memcg cftypes in the current
>> cgroup/for-3.5 branch?
>
> Ugh... brainfart.  Please disregard the previous message.  Can you
> please resend the patches on top of cgroup/for-3.5 and use Li's new
> address - lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org ?
>
> Thanks.
>
All right.
I'll give a new test to make sure it is still okay, and send shortly

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Tejun Heo]

On Tue, Apr 03, 2012 at 11:47:19AM -0700, Tejun Heo wrote:
> Hello, Glauber.
> 
> On Tue, Apr 03, 2012 at 07:22:59AM +0400, Glauber Costa wrote:
> > Do I need to send you a patch to remove memcg's populate on top of this ?
> 
> populate is already gone.  My memory is a bit fuzzy now.  Can you spot
> something broken / to be improved re. memcg cftypes in the current
> cgroup/for-3.5 branch?

Ugh... brainfart.  Please disregard the previous message.  Can you
please resend the patches on top of cgroup/for-3.5 and use Li's new
address - lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org ?

Thanks.

-- 
tejun

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Tejun Heo]

On Tue, Apr 03, 2012 at 11:47:19AM -0700, Tejun Heo wrote:
> Hello, Glauber.
> 
> On Tue, Apr 03, 2012 at 07:22:59AM +0400, Glauber Costa wrote:
> > Do I need to send you a patch to remove memcg's populate on top of this ?
> 
> populate is already gone.  My memory is a bit fuzzy now.  Can you spot
> something broken / to be improved re. memcg cftypes in the current
> cgroup/for-3.5 branch?

Ugh... brainfart.  Please disregard the previous message.  Can you
please resend the patches on top of cgroup/for-3.5 and use Li's new
address - lizefan@huawei.com ?

Thanks.

-- 
tejun

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Tejun Heo]

On Tue, Apr 03, 2012 at 11:47:19AM -0700, Tejun Heo wrote:
> Hello, Glauber.
> 
> On Tue, Apr 03, 2012 at 07:22:59AM +0400, Glauber Costa wrote:
> > Do I need to send you a patch to remove memcg's populate on top of this ?
> 
> populate is already gone.  My memory is a bit fuzzy now.  Can you spot
> something broken / to be improved re. memcg cftypes in the current
> cgroup/for-3.5 branch?

Ugh... brainfart.  Please disregard the previous message.  Can you
please resend the patches on top of cgroup/for-3.5 and use Li's new
address - lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org ?

Thanks.

-- 
tejun

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Tejun Heo]

Hello, Glauber.

On Tue, Apr 03, 2012 at 07:22:59AM +0400, Glauber Costa wrote:
> Do I need to send you a patch to remove memcg's populate on top of this ?

populate is already gone.  My memory is a bit fuzzy now.  Can you spot
something broken / to be improved re. memcg cftypes in the current
cgroup/for-3.5 branch?

Thanks.

-- 
tejun

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Tejun Heo]

Hello, Glauber.

On Tue, Apr 03, 2012 at 07:22:59AM +0400, Glauber Costa wrote:
> Do I need to send you a patch to remove memcg's populate on top of this ?

populate is already gone.  My memory is a bit fuzzy now.  Can you spot
something broken / to be improved re. memcg cftypes in the current
cgroup/for-3.5 branch?

Thanks.

-- 
tejun

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Glauber Costa]

On 03/31/2012 02:29 AM, Tejun Heo wrote:
> On Wed, Mar 21, 2012 at 03:17:33PM -0700, Tejun Heo wrote:
>> and is also available in the following git branch.
>>
>>   git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc.git cgroup-cftype
>
> Branch has been refreshed on top of the current mainline and with the
> updated patch.
>
> Thanks.
>
Do I need to send you a patch to remove memcg's populate on top of this ?

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Glauber Costa]

On 03/31/2012 02:29 AM, Tejun Heo wrote:
> On Wed, Mar 21, 2012 at 03:17:33PM -0700, Tejun Heo wrote:
>> and is also available in the following git branch.
>>
>>   git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc.git cgroup-cftype
>
> Branch has been refreshed on top of the current mainline and with the
> updated patch.
>
> Thanks.
>
Do I need to send you a patch to remove memcg's populate on top of this ?

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Glauber Costa]

On 03/31/2012 02:29 AM, Tejun Heo wrote:
> On Wed, Mar 21, 2012 at 03:17:33PM -0700, Tejun Heo wrote:
>> and is also available in the following git branch.
>>
>>   git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc.git cgroup-cftype
>
> Branch has been refreshed on top of the current mainline and with the
> updated patch.
>
> Thanks.
>
Do I need to send you a patch to remove memcg's populate on top of this ?

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Tejun Heo]

On Wed, Mar 21, 2012 at 03:17:33PM -0700, Tejun Heo wrote:
> This is the second take at improving cgroup file addition/removal
> interface.  Changes from the last take[L] are,

Applied to cgroup/for-3.5 w/ Li's acks added.

Thanks.

-- 
tejun

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Tejun Heo]

On Wed, Mar 21, 2012 at 03:17:33PM -0700, Tejun Heo wrote:
> This is the second take at improving cgroup file addition/removal
> interface.  Changes from the last take[L] are,

Applied to cgroup/for-3.5 w/ Li's acks added.

Thanks.

-- 
tejun

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Tejun Heo]

On Wed, Mar 21, 2012 at 03:17:33PM -0700, Tejun Heo wrote:
> This is the second take at improving cgroup file addition/removal
> interface.  Changes from the last take[L] are,

Applied to cgroup/for-3.5 w/ Li's acks added.

Thanks.

-- 
tejun

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Tejun Heo]

Hello,

On Sat, Mar 31, 2012 at 08:44:23PM +0800, Li Zefan wrote:
> I've gone through the whole patchset, feel free to add my acks.

I'll add acked-by's to all patches including the remount deprecation
patch and start cgroup/for-3.5 branch.  If there's any disagreement,
please scream.

Thanks.

-- 
tejun

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Tejun Heo]

Hello,

On Sat, Mar 31, 2012 at 08:44:23PM +0800, Li Zefan wrote:
> I've gone through the whole patchset, feel free to add my acks.

I'll add acked-by's to all patches including the remount deprecation
patch and start cgroup/for-3.5 branch.  If there's any disagreement,
please scream.

Thanks.

-- 
tejun

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Tejun Heo]

Hello,

On Sat, Mar 31, 2012 at 08:44:23PM +0800, Li Zefan wrote:
> I've gone through the whole patchset, feel free to add my acks.

I'll add acked-by's to all patches including the remount deprecation
patch and start cgroup/for-3.5 branch.  If there's any disagreement,
please scream.

Thanks.

-- 
tejun

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Tejun Heo]

Hello,

On Sat, Mar 31, 2012 at 08:56:36PM +0800, Li Zefan wrote:
> > Subsys can't be changed if any non-root cgroup exists.
> 
> Ah, this is a long-standing defect, which is documented in Doc/../cgroups.txt.
> It's not trivial to fix it, and I never heard someone request it to be fixed.

Yeah, it was a bit of head scratcher.  If it can be done only when
there's no cgroup configured, one might as well unmount and mount w/
new subsys instead of remounting.  There's the minute difference that
existing root cgroup state is preserved but that hardly justifies the
crippled feature.  IMHO, lack of fix request indicates the feature not
being used rather than anything else, so the deprecation proposal.

Thanks.

-- 
tejun

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Tejun Heo]

Hello,

On Sat, Mar 31, 2012 at 08:56:36PM +0800, Li Zefan wrote:
> > Subsys can't be changed if any non-root cgroup exists.
> 
> Ah, this is a long-standing defect, which is documented in Doc/../cgroups.txt.
> It's not trivial to fix it, and I never heard someone request it to be fixed.

Yeah, it was a bit of head scratcher.  If it can be done only when
there's no cgroup configured, one might as well unmount and mount w/
new subsys instead of remounting.  There's the minute difference that
existing root cgroup state is preserved but that hardly justifies the
crippled feature.  IMHO, lack of fix request indicates the feature not
being used rather than anything else, so the deprecation proposal.

Thanks.

-- 
tejun

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Tejun Heo]

Hello,

On Sat, Mar 31, 2012 at 08:56:36PM +0800, Li Zefan wrote:
> > Subsys can't be changed if any non-root cgroup exists.
> 
> Ah, this is a long-standing defect, which is documented in Doc/../cgroups.txt.
> It's not trivial to fix it, and I never heard someone request it to be fixed.

Yeah, it was a bit of head scratcher.  If it can be done only when
there's no cgroup configured, one might as well unmount and mount w/
new subsys instead of remounting.  There's the minute difference that
existing root cgroup state is preserved but that hardly justifies the
crippled feature.  IMHO, lack of fix request indicates the feature not
being used rather than anything else, so the deprecation proposal.

Thanks.

-- 
tejun

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Li Zefan]

Tejun Heo wrote:

> Hey, Li.
> 
> On Fri, Mar 30, 2012 at 08:42:07PM +0800, Li Zefan wrote:
>>> This patch replaces cgroup file interface with cftype based one which
>>> allows dynamic additions and removals of cftype arrays whether the
>>> target subsystem is attached or not.  This can be used to make subsys
>>> rebinding via remount work properly but I intentionally avoided doing
>>> that at the moment.
>>
>> What's the problem with remount?
> 
> Subsys can't be changed if any non-root cgroup exists.
> 


Ah, this is a long-standing defect, which is documented in Doc/../cgroups.txt.
It's not trivial to fix it, and I never heard someone request it to be fixed.

>> and is it important enough that it should be fixed even the feature
>> is marked as deprecated?
> 
> I'm not sure.  We *might* need it during multi-mount -> single-mount
> transition depending on how that's implemented, so the "at the moment"
> qualifier.  It probably won't be fixed but I'm not fully sure.
> 


fine.

>>> This makes cgroup population simpler for controllers and will be used
>>> to allow controllers to be more dynamic.  e.g. blkio subsys has
>>> sub-policies which may come and go while blkio subsys is attached and
>>> it currently uses fixed set of files which stays blank if not in use.
>>
>> Dynamic cgroup files was mentioned before. The scenario in mind was blkio
>> control files can be added/removed automatically as devices come and ago.
>>
>> So this time blkio subsystem is really going to be made more dynamic
>> soon?
> 
> Patchset already posted.
> 
>   http://thread.gmane.org/gmane.linux.kernel.cgroups/1376
> 


Thanks!

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Li Zefan]

Tejun Heo wrote:

> Hey, Li.
> 
> On Fri, Mar 30, 2012 at 08:42:07PM +0800, Li Zefan wrote:
>>> This patch replaces cgroup file interface with cftype based one which
>>> allows dynamic additions and removals of cftype arrays whether the
>>> target subsystem is attached or not.  This can be used to make subsys
>>> rebinding via remount work properly but I intentionally avoided doing
>>> that at the moment.
>>
>> What's the problem with remount?
> 
> Subsys can't be changed if any non-root cgroup exists.
> 


Ah, this is a long-standing defect, which is documented in Doc/../cgroups.txt.
It's not trivial to fix it, and I never heard someone request it to be fixed.

>> and is it important enough that it should be fixed even the feature
>> is marked as deprecated?
> 
> I'm not sure.  We *might* need it during multi-mount -> single-mount
> transition depending on how that's implemented, so the "at the moment"
> qualifier.  It probably won't be fixed but I'm not fully sure.
> 


fine.

>>> This makes cgroup population simpler for controllers and will be used
>>> to allow controllers to be more dynamic.  e.g. blkio subsys has
>>> sub-policies which may come and go while blkio subsys is attached and
>>> it currently uses fixed set of files which stays blank if not in use.
>>
>> Dynamic cgroup files was mentioned before. The scenario in mind was blkio
>> control files can be added/removed automatically as devices come and ago.
>>
>> So this time blkio subsystem is really going to be made more dynamic
>> soon?
> 
> Patchset already posted.
> 
>   http://thread.gmane.org/gmane.linux.kernel.cgroups/1376
> 


Thanks!

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Li Zefan]

Tejun Heo wrote:

> Hey, Li.
> 
> On Fri, Mar 30, 2012 at 08:42:07PM +0800, Li Zefan wrote:
>>> This patch replaces cgroup file interface with cftype based one which
>>> allows dynamic additions and removals of cftype arrays whether the
>>> target subsystem is attached or not.  This can be used to make subsys
>>> rebinding via remount work properly but I intentionally avoided doing
>>> that at the moment.
>>
>> What's the problem with remount?
> 
> Subsys can't be changed if any non-root cgroup exists.
> 


Ah, this is a long-standing defect, which is documented in Doc/../cgroups.txt.
It's not trivial to fix it, and I never heard someone request it to be fixed.

>> and is it important enough that it should be fixed even the feature
>> is marked as deprecated?
> 
> I'm not sure.  We *might* need it during multi-mount -> single-mount
> transition depending on how that's implemented, so the "at the moment"
> qualifier.  It probably won't be fixed but I'm not fully sure.
> 


fine.

>>> This makes cgroup population simpler for controllers and will be used
>>> to allow controllers to be more dynamic.  e.g. blkio subsys has
>>> sub-policies which may come and go while blkio subsys is attached and
>>> it currently uses fixed set of files which stays blank if not in use.
>>
>> Dynamic cgroup files was mentioned before. The scenario in mind was blkio
>> control files can be added/removed automatically as devices come and ago.
>>
>> So this time blkio subsystem is really going to be made more dynamic
>> soon?
> 
> Patchset already posted.
> 
>   http://thread.gmane.org/gmane.linux.kernel.cgroups/1376
> 


Thanks!

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Li Zefan]

Tejun Heo wrote:

> On Wed, Mar 21, 2012 at 03:17:33PM -0700, Tejun Heo wrote:
>> and is also available in the following git branch.
>>
>>  git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc.git cgroup-cftype
> 
> Branch has been refreshed on top of the current mainline and with the
> updated patch.
> 


I've gone through the whole patchset, feel free to add my acks.

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Li Zefan]

Tejun Heo wrote:

> On Wed, Mar 21, 2012 at 03:17:33PM -0700, Tejun Heo wrote:
>> and is also available in the following git branch.
>>
>>  git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc.git cgroup-cftype
> 
> Branch has been refreshed on top of the current mainline and with the
> updated patch.
> 


I've gone through the whole patchset, feel free to add my acks.

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Tejun Heo]

On Wed, Mar 21, 2012 at 03:17:33PM -0700, Tejun Heo wrote:
> and is also available in the following git branch.
> 
>  git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc.git cgroup-cftype

Branch has been refreshed on top of the current mainline and with the
updated patch.

Thanks.

-- 
tejun

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Tejun Heo]

On Wed, Mar 21, 2012 at 03:17:33PM -0700, Tejun Heo wrote:
> and is also available in the following git branch.
> 
>  git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc.git cgroup-cftype

Branch has been refreshed on top of the current mainline and with the
updated patch.

Thanks.

-- 
tejun

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Tejun Heo]

Hey, Li.

On Fri, Mar 30, 2012 at 08:42:07PM +0800, Li Zefan wrote:
> > This patch replaces cgroup file interface with cftype based one which
> > allows dynamic additions and removals of cftype arrays whether the
> > target subsystem is attached or not.  This can be used to make subsys
> > rebinding via remount work properly but I intentionally avoided doing
> > that at the moment.
> 
> What's the problem with remount?

Subsys can't be changed if any non-root cgroup exists.

> and is it important enough that it should be fixed even the feature
> is marked as deprecated?

I'm not sure.  We *might* need it during multi-mount -> single-mount
transition depending on how that's implemented, so the "at the moment"
qualifier.  It probably won't be fixed but I'm not fully sure.

> > This makes cgroup population simpler for controllers and will be used
> > to allow controllers to be more dynamic.  e.g. blkio subsys has
> > sub-policies which may come and go while blkio subsys is attached and
> > it currently uses fixed set of files which stays blank if not in use.
> 
> Dynamic cgroup files was mentioned before. The scenario in mind was blkio
> control files can be added/removed automatically as devices come and ago.
> 
> So this time blkio subsystem is really going to be made more dynamic
> soon?

Patchset already posted.

  http://thread.gmane.org/gmane.linux.kernel.cgroups/1376

Thanks.

-- 
tejun

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Tejun Heo]

Hey, Li.

On Fri, Mar 30, 2012 at 08:42:07PM +0800, Li Zefan wrote:
> > This patch replaces cgroup file interface with cftype based one which
> > allows dynamic additions and removals of cftype arrays whether the
> > target subsystem is attached or not.  This can be used to make subsys
> > rebinding via remount work properly but I intentionally avoided doing
> > that at the moment.
> 
> What's the problem with remount?

Subsys can't be changed if any non-root cgroup exists.

> and is it important enough that it should be fixed even the feature
> is marked as deprecated?

I'm not sure.  We *might* need it during multi-mount -> single-mount
transition depending on how that's implemented, so the "at the moment"
qualifier.  It probably won't be fixed but I'm not fully sure.

> > This makes cgroup population simpler for controllers and will be used
> > to allow controllers to be more dynamic.  e.g. blkio subsys has
> > sub-policies which may come and go while blkio subsys is attached and
> > it currently uses fixed set of files which stays blank if not in use.
> 
> Dynamic cgroup files was mentioned before. The scenario in mind was blkio
> control files can be added/removed automatically as devices come and ago.
> 
> So this time blkio subsystem is really going to be made more dynamic
> soon?

Patchset already posted.

  http://thread.gmane.org/gmane.linux.kernel.cgroups/1376

Thanks.

-- 
tejun

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Li Zefan]

Tejun Heo wrote:

> Hello,
> 
> This is the second take at improving cgroup file addition/removal
> interface.  Changes from the last take[L] are,
> 
> * CGROUP_SUBSYS_CFTYPES[_COND]() dropped and
>   cgroup_subsys->base_cftypes is added instead.  This works better for
>   subsystems implemented as module.  tcp_memcontrol now uses an
>   explicit __initcall() to register its cftypes.
> 
> * 0005-cgroup-relocate-cftype-and-cgroup_subsys-definitions.patch
>   added as cleanup.
> 
> * 0007-memcg-always-create-memsw-files-if-CONFIG_CGROUP_MEM.patch
>   added so that memsw files are always created if enabled in config as
>   suggested by KAMEZAWA.
> 
> This patch replaces cgroup file interface with cftype based one which
> allows dynamic additions and removals of cftype arrays whether the
> target subsystem is attached or not.  This can be used to make subsys
> rebinding via remount work properly but I intentionally avoided doing
> that at the moment.
> 


What's the problem with remount? and is it important enough that it
should be fixed even the feature is marked as deprecated?

> This makes cgroup population simpler for controllers and will be used
> to allow controllers to be more dynamic.  e.g. blkio subsys has
> sub-policies which may come and go while blkio subsys is attached and
> it currently uses fixed set of files which stays blank if not in use.


Dynamic cgroup files was mentioned before. The scenario in mind was blkio
control files can be added/removed automatically as devices come and ago.

So this time blkio subsystem is really going to be made more dynamic
soon?

> This will also be useful for implementing unified hierarchy.
> 

> This patchset contains the following patches.

> 


I'll look into the patches tomorrow.

>  0001-cgroup-move-cgroup_clear_directory-call-out-of-cgrou.patch
>  0002-cgroup-build-list-of-all-cgroups-under-a-given-cgrou.patch
>  0003-cgroup-implement-cgroup_add_cftypes-and-friends.patch
>  0004-cgroup-merge-cft_release_agent-cftype-array-into-the.patch
>  0005-cgroup-relocate-cftype-and-cgroup_subsys-definitions.patch
>  0006-cgroup-convert-all-non-memcg-controllers-to-the-new-.patch
>  0007-memcg-always-create-memsw-files-if-CONFIG_CGROUP_MEM.patch
>  0008-cgroup-convert-memcg-controller-to-the-new-cftype-in.patch
>  0009-cgroup-remove-cgroup_add_file-s.patch
>  0010-cgroup-relocate-__d_cgrp-and-__d_cft.patch
>  0011-cgroup-introduce-struct-cfent.patch
>  0012-cgroup-implement-cgroup_rm_cftypes.patch
> 
> and is on top of
> 
>   cgroup/for-3.4 3ce3230a0cff484e5130153f244d4fb8a56b3a8b
> + [1] cgroup: deprecate remount option changes mount option
> 
> and is also available in the following git branch.
> 
>  git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc.git cgroup-cftype
> 
> Glauber, I think the cftypes registration for tcp_memcontrol is fine
> as is in this patchset and we just need to move the init to the tail
> of ->create().  Let's worry about memcg for module-loadable protocols
> whey they are added.  Can you please send a patch to move init to
> ->create()?
> 
> If nobody objects && after Li comes back and acks the changes, I'll
> route these through cgroup/for-3.5.

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Li Zefan]

Tejun Heo wrote:

> Hello,
> 
> This is the second take at improving cgroup file addition/removal
> interface.  Changes from the last take[L] are,
> 
> * CGROUP_SUBSYS_CFTYPES[_COND]() dropped and
>   cgroup_subsys->base_cftypes is added instead.  This works better for
>   subsystems implemented as module.  tcp_memcontrol now uses an
>   explicit __initcall() to register its cftypes.
> 
> * 0005-cgroup-relocate-cftype-and-cgroup_subsys-definitions.patch
>   added as cleanup.
> 
> * 0007-memcg-always-create-memsw-files-if-CONFIG_CGROUP_MEM.patch
>   added so that memsw files are always created if enabled in config as
>   suggested by KAMEZAWA.
> 
> This patch replaces cgroup file interface with cftype based one which
> allows dynamic additions and removals of cftype arrays whether the
> target subsystem is attached or not.  This can be used to make subsys
> rebinding via remount work properly but I intentionally avoided doing
> that at the moment.
> 


What's the problem with remount? and is it important enough that it
should be fixed even the feature is marked as deprecated?

> This makes cgroup population simpler for controllers and will be used
> to allow controllers to be more dynamic.  e.g. blkio subsys has
> sub-policies which may come and go while blkio subsys is attached and
> it currently uses fixed set of files which stays blank if not in use.


Dynamic cgroup files was mentioned before. The scenario in mind was blkio
control files can be added/removed automatically as devices come and ago.

So this time blkio subsystem is really going to be made more dynamic
soon?

> This will also be useful for implementing unified hierarchy.
> 

> This patchset contains the following patches.

> 


I'll look into the patches tomorrow.

>  0001-cgroup-move-cgroup_clear_directory-call-out-of-cgrou.patch
>  0002-cgroup-build-list-of-all-cgroups-under-a-given-cgrou.patch
>  0003-cgroup-implement-cgroup_add_cftypes-and-friends.patch
>  0004-cgroup-merge-cft_release_agent-cftype-array-into-the.patch
>  0005-cgroup-relocate-cftype-and-cgroup_subsys-definitions.patch
>  0006-cgroup-convert-all-non-memcg-controllers-to-the-new-.patch
>  0007-memcg-always-create-memsw-files-if-CONFIG_CGROUP_MEM.patch
>  0008-cgroup-convert-memcg-controller-to-the-new-cftype-in.patch
>  0009-cgroup-remove-cgroup_add_file-s.patch
>  0010-cgroup-relocate-__d_cgrp-and-__d_cft.patch
>  0011-cgroup-introduce-struct-cfent.patch
>  0012-cgroup-implement-cgroup_rm_cftypes.patch
> 
> and is on top of
> 
>   cgroup/for-3.4 3ce3230a0cff484e5130153f244d4fb8a56b3a8b
> + [1] cgroup: deprecate remount option changes mount option
> 
> and is also available in the following git branch.
> 
>  git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc.git cgroup-cftype
> 
> Glauber, I think the cftypes registration for tcp_memcontrol is fine
> as is in this patchset and we just need to move the init to the tail
> of ->create().  Let's worry about memcg for module-loadable protocols
> whey they are added.  Can you please send a patch to move init to
> ->create()?
> 
> If nobody objects && after Li comes back and acks the changes, I'll
> route these through cgroup/for-3.5.

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Li Zefan]

Tejun Heo wrote:

> Hello,
> 
> This is the second take at improving cgroup file addition/removal
> interface.  Changes from the last take[L] are,
> 
> * CGROUP_SUBSYS_CFTYPES[_COND]() dropped and
>   cgroup_subsys->base_cftypes is added instead.  This works better for
>   subsystems implemented as module.  tcp_memcontrol now uses an
>   explicit __initcall() to register its cftypes.
> 
> * 0005-cgroup-relocate-cftype-and-cgroup_subsys-definitions.patch
>   added as cleanup.
> 
> * 0007-memcg-always-create-memsw-files-if-CONFIG_CGROUP_MEM.patch
>   added so that memsw files are always created if enabled in config as
>   suggested by KAMEZAWA.
> 
> This patch replaces cgroup file interface with cftype based one which
> allows dynamic additions and removals of cftype arrays whether the
> target subsystem is attached or not.  This can be used to make subsys
> rebinding via remount work properly but I intentionally avoided doing
> that at the moment.
> 


What's the problem with remount? and is it important enough that it
should be fixed even the feature is marked as deprecated?

> This makes cgroup population simpler for controllers and will be used
> to allow controllers to be more dynamic.  e.g. blkio subsys has
> sub-policies which may come and go while blkio subsys is attached and
> it currently uses fixed set of files which stays blank if not in use.


Dynamic cgroup files was mentioned before. The scenario in mind was blkio
control files can be added/removed automatically as devices come and ago.

So this time blkio subsystem is really going to be made more dynamic
soon?

> This will also be useful for implementing unified hierarchy.
> 

> This patchset contains the following patches.

> 


I'll look into the patches tomorrow.

>  0001-cgroup-move-cgroup_clear_directory-call-out-of-cgrou.patch
>  0002-cgroup-build-list-of-all-cgroups-under-a-given-cgrou.patch
>  0003-cgroup-implement-cgroup_add_cftypes-and-friends.patch
>  0004-cgroup-merge-cft_release_agent-cftype-array-into-the.patch
>  0005-cgroup-relocate-cftype-and-cgroup_subsys-definitions.patch
>  0006-cgroup-convert-all-non-memcg-controllers-to-the-new-.patch
>  0007-memcg-always-create-memsw-files-if-CONFIG_CGROUP_MEM.patch
>  0008-cgroup-convert-memcg-controller-to-the-new-cftype-in.patch
>  0009-cgroup-remove-cgroup_add_file-s.patch
>  0010-cgroup-relocate-__d_cgrp-and-__d_cft.patch
>  0011-cgroup-introduce-struct-cfent.patch
>  0012-cgroup-implement-cgroup_rm_cftypes.patch
> 
> and is on top of
> 
>   cgroup/for-3.4 3ce3230a0cff484e5130153f244d4fb8a56b3a8b
> + [1] cgroup: deprecate remount option changes mount option
> 
> and is also available in the following git branch.
> 
>  git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc.git cgroup-cftype
> 
> Glauber, I think the cftypes registration for tcp_memcontrol is fine
> as is in this patchset and we just need to move the init to the tail
> of ->create().  Let's worry about memcg for module-loadable protocols
> whey they are added.  Can you please send a patch to move init to
> ->create()?
> 
> If nobody objects && after Li comes back and acks the changes, I'll
> route these through cgroup/for-3.5.

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Glauber Costa]

On 03/22/2012 02:17 AM, Tejun Heo wrote:
> Can you please send a patch to move init to
> ->create()?

Yes.

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Glauber Costa]

On 03/22/2012 02:17 AM, Tejun Heo wrote:
> Can you please send a patch to move init to
> ->create()?

Yes.

Re: [PATCHSET] cgroup: cftype based file interface, take #2

[Glauber Costa]

On 03/22/2012 02:17 AM, Tejun Heo wrote:
> Can you please send a patch to move init to
> ->create()?

Yes.

[PATCHSET] cgroup: cftype based file interface, take #2

[Tejun Heo]

Hello,

This is the second take at improving cgroup file addition/removal
interface.  Changes from the last take[L] are,

* CGROUP_SUBSYS_CFTYPES[_COND]() dropped and
  cgroup_subsys->base_cftypes is added instead.  This works better for
  subsystems implemented as module.  tcp_memcontrol now uses an
  explicit __initcall() to register its cftypes.

* 0005-cgroup-relocate-cftype-and-cgroup_subsys-definitions.patch
  added as cleanup.

* 0007-memcg-always-create-memsw-files-if-CONFIG_CGROUP_MEM.patch
  added so that memsw files are always created if enabled in config as
  suggested by KAMEZAWA.

This patch replaces cgroup file interface with cftype based one which
allows dynamic additions and removals of cftype arrays whether the
target subsystem is attached or not.  This can be used to make subsys
rebinding via remount work properly but I intentionally avoided doing
that at the moment.

This makes cgroup population simpler for controllers and will be used
to allow controllers to be more dynamic.  e.g. blkio subsys has
sub-policies which may come and go while blkio subsys is attached and
it currently uses fixed set of files which stays blank if not in use.
This will also be useful for implementing unified hierarchy.

This patchset contains the following patches.

 0001-cgroup-move-cgroup_clear_directory-call-out-of-cgrou.patch
 0002-cgroup-build-list-of-all-cgroups-under-a-given-cgrou.patch
 0003-cgroup-implement-cgroup_add_cftypes-and-friends.patch
 0004-cgroup-merge-cft_release_agent-cftype-array-into-the.patch
 0005-cgroup-relocate-cftype-and-cgroup_subsys-definitions.patch
 0006-cgroup-convert-all-non-memcg-controllers-to-the-new-.patch
 0007-memcg-always-create-memsw-files-if-CONFIG_CGROUP_MEM.patch
 0008-cgroup-convert-memcg-controller-to-the-new-cftype-in.patch
 0009-cgroup-remove-cgroup_add_file-s.patch
 0010-cgroup-relocate-__d_cgrp-and-__d_cft.patch
 0011-cgroup-introduce-struct-cfent.patch
 0012-cgroup-implement-cgroup_rm_cftypes.patch

and is on top of

  cgroup/for-3.4 3ce3230a0cff484e5130153f244d4fb8a56b3a8b
+ [1] cgroup: deprecate remount option changes mount option

and is also available in the following git branch.

 git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc.git cgroup-cftype

Glauber, I think the cftypes registration for tcp_memcontrol is fine
as is in this patchset and we just need to move the init to the tail
of ->create().  Let's worry about memcg for module-loadable protocols
whey they are added.  Can you please send a patch to move init to
->create()?

If nobody objects && after Li comes back and acks the changes, I'll
route these through cgroup/for-3.5.

diffstat follows.

 block/blk-cgroup.c        |   45 ++---
 include/linux/cgroup.h    |   51 ++++--
 kernel/cgroup.c           |  359 +++++++++++++++++++++++++++++++++++-----------
 kernel/cgroup_freezer.c   |   11 -
 kernel/cpuset.c           |   31 +--
 kernel/sched/core.c       |   16 --
 mm/memcontrol.c           |   77 ++++-----
 net/core/netprio_cgroup.c |   30 +--
 net/ipv4/tcp_memcontrol.c |   71 ++++-----
 net/sched/cls_cgroup.c    |   31 +--
 security/device_cgroup.c  |   10 -
 11 files changed, 437 insertions(+), 295 deletions(-)

Thanks.

--
tejun

[L] http://thread.gmane.org/gmane.linux.kernel.containers/22623
[1] http://thread.gmane.org/gmane.linux.kernel.cgroups/1192/focus=22611

[PATCHSET] cgroup: cftype based file interface, take #2

[Tejun Heo]

Hello,

This is the second take at improving cgroup file addition/removal
interface.  Changes from the last take[L] are,

* CGROUP_SUBSYS_CFTYPES[_COND]() dropped and
  cgroup_subsys->base_cftypes is added instead.  This works better for
  subsystems implemented as module.  tcp_memcontrol now uses an
  explicit __initcall() to register its cftypes.

* 0005-cgroup-relocate-cftype-and-cgroup_subsys-definitions.patch
  added as cleanup.

* 0007-memcg-always-create-memsw-files-if-CONFIG_CGROUP_MEM.patch
  added so that memsw files are always created if enabled in config as
  suggested by KAMEZAWA.

This patch replaces cgroup file interface with cftype based one which
allows dynamic additions and removals of cftype arrays whether the
target subsystem is attached or not.  This can be used to make subsys
rebinding via remount work properly but I intentionally avoided doing
that at the moment.

This makes cgroup population simpler for controllers and will be used
to allow controllers to be more dynamic.  e.g. blkio subsys has
sub-policies which may come and go while blkio subsys is attached and
it currently uses fixed set of files which stays blank if not in use.
This will also be useful for implementing unified hierarchy.

This patchset contains the following patches.

 0001-cgroup-move-cgroup_clear_directory-call-out-of-cgrou.patch
 0002-cgroup-build-list-of-all-cgroups-under-a-given-cgrou.patch
 0003-cgroup-implement-cgroup_add_cftypes-and-friends.patch
 0004-cgroup-merge-cft_release_agent-cftype-array-into-the.patch
 0005-cgroup-relocate-cftype-and-cgroup_subsys-definitions.patch
 0006-cgroup-convert-all-non-memcg-controllers-to-the-new-.patch
 0007-memcg-always-create-memsw-files-if-CONFIG_CGROUP_MEM.patch
 0008-cgroup-convert-memcg-controller-to-the-new-cftype-in.patch
 0009-cgroup-remove-cgroup_add_file-s.patch
 0010-cgroup-relocate-__d_cgrp-and-__d_cft.patch
 0011-cgroup-introduce-struct-cfent.patch
 0012-cgroup-implement-cgroup_rm_cftypes.patch

and is on top of

  cgroup/for-3.4 3ce3230a0cff484e5130153f244d4fb8a56b3a8b
+ [1] cgroup: deprecate remount option changes mount option

and is also available in the following git branch.

 git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc.git cgroup-cftype

Glauber, I think the cftypes registration for tcp_memcontrol is fine
as is in this patchset and we just need to move the init to the tail
of ->create().  Let's worry about memcg for module-loadable protocols
whey they are added.  Can you please send a patch to move init to
->create()?

If nobody objects && after Li comes back and acks the changes, I'll
route these through cgroup/for-3.5.

diffstat follows.

 block/blk-cgroup.c        |   45 ++---
 include/linux/cgroup.h    |   51 ++++--
 kernel/cgroup.c           |  359 +++++++++++++++++++++++++++++++++++-----------
 kernel/cgroup_freezer.c   |   11 -
 kernel/cpuset.c           |   31 +--
 kernel/sched/core.c       |   16 --
 mm/memcontrol.c           |   77 ++++-----
 net/core/netprio_cgroup.c |   30 +--
 net/ipv4/tcp_memcontrol.c |   71 ++++-----
 net/sched/cls_cgroup.c    |   31 +--
 security/device_cgroup.c  |   10 -
 11 files changed, 437 insertions(+), 295 deletions(-)

Thanks.

--
tejun

[L] http://thread.gmane.org/gmane.linux.kernel.containers/22623
[1] http://thread.gmane.org/gmane.linux.kernel.cgroups/1192/focus=22611