linux.git/include/linux/cgroup.h, branch v2.6.26-rc2

cgroups: add an owner to the mm_struct

2008-04-29T15:06:10+00:00

Remove the mem_cgroup member from mm_struct and instead adds an owner.

This approach was suggested by Paul Menage.  The advantage of this approach
is that, once the mm->owner is known, using the subsystem id, the cgroup
can be determined.  It also allows several control groups that are
virtually grouped by mm_struct, to exist independent of the memory
controller i.e., without adding mem_cgroup's for each controller, to
mm_struct.

A new config option CONFIG_MM_OWNER is added and the memory resource
controller selects this config option.

This patch also adds cgroup callbacks to notify subsystems when mm->owner
changes.  The mm_cgroup_changed callback is called with the task_lock() of
the new task held and is called just prior to changing the mm->owner.

I am indebted to Paul Menage for the several reviews of this patchset and
helping me make it lighter and simpler.

This patch was tested on a powerpc box, it was compiled with both the
MM_OWNER config turned on and off.

After the thread group leader exits, it's moved to init_css_state by
cgroup_exit(), thus all future charges from runnings threads would be
redirected to the init_css_set's subsystem.

Signed-off-by: Balbir Singh 
Cc: Pavel Emelianov 
Cc: Hugh Dickins 
Cc: Sudhir Kumar 
Cc: YAMAMOTO Takashi 
Cc: Hirokazu Takahashi 
Cc: David Rientjes ,
Cc: Balbir Singh 
Acked-by: KAMEZAWA Hiroyuki 
Acked-by: Pekka Enberg 
Reviewed-by: Paul Menage 
Cc: Oleg Nesterov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

cgroups: introduce cft->read_seq()

2008-04-29T15:06:10+00:00

Introduce a read_seq() helper in cftype, which uses seq_file to print out
lists.  Use it in the devices cgroup.  Also split devices.allow into two
files, so now devices.deny and devices.allow are the ones to use to manipulate
the whitelist, while devices.list outputs the cgroup's current whitelist.

Signed-off-by: Serge E. Hallyn 
Acked-by: Paul Menage 
Cc: Balbir Singh 
Cc: KAMEZAWA Hiroyuki 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

cgroups: remove the css_set linked-list

2008-04-29T15:06:10+00:00

Now we can run through the hash table instead of running through the
linked-list.

Signed-off-by: Li Zefan 
Reviewed-by: Paul Menage 
Cc: Balbir Singh 
Cc: Pavel Emelyanov 
Cc: KAMEZAWA Hiroyuki 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

cgroups: use a hash table for css_set finding

2008-04-29T15:06:09+00:00

When we attach a process to a different cgroup, the css_set linked-list will
be run through to find a suitable existing css_set to use.  This patch
implements a hash table for better performance.

The following benchmarks have been tested:

For N in 1, 5, 10, 50, 100, 500, 1000, create N cgroups with one sleeping
task in each, and then move an additional task through each cgroup in
turn.

Here is a test result:

N	Loop	orig - Time(s)	hash - Time(s)
----------------------------------------------
1	10000	1.201231728	1.196311177
5	2000	1.065743872	1.040566424
10	1000	0.991054735	0.986876440
50	200	0.976554203	0.969608733
100	100	0.998504680	0.969218270
500	20	1.157347764	0.962602963
1000	10	1.619521852	1.085140172

Signed-off-by: Li Zefan 
Reviewed-by: Paul Menage 
Cc: Balbir Singh 
Cc: Pavel Emelyanov 
Cc: KAMEZAWA Hiroyuki 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

cgroups: add the trigger callback to struct cftype

2008-04-29T15:06:09+00:00

Trigger callback can be used to receive a kick-up from the user space.  The
string written is ignored.

The cftype->private is used for multiplexing events.

Signed-off-by: Pavel Emelyanov 
Acked-by: Paul Menage 
Acked-by: KAMEZAWA Hiroyuki 
Cc: Balbir Singh 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

CGroups _s64 files: add cgroups read_s64/write_s64 file methods

2008-04-29T15:06:09+00:00

These patches add cgroups read_s64 and write_s64 control file methods (the
signed equivalent of read_u64/write_u64) and use them to implement the
cpu.rt_runtime_us control file in the CFS cgroup subsystem.

This patch:

These are the signed equivalents of the read_u64/write_u64 methods

Signed-off-by: Paul Menage 
Acked-by: Peter Zijlstra 
Cc: Ingo Molnar 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

CGroup API files: move "releasable" to cgroup_debug subsystem

2008-04-29T15:06:09+00:00

The "releasable" control file provided by the cgroup framework exports the
state of a per-cgroup flag that's related to the notify-on-release feature.
This isn't really generally useful, unless you're trying to debug this
particular feature of cgroups.

This patch moves the "releasable" file to the cgroup_debug subsystem.

Signed-off-by: Paul Menage 
Cc: "Li Zefan" 
Cc: Balbir Singh 
Cc: Paul Jackson 
Cc: Pavel Emelyanov 
Cc: KAMEZAWA Hiroyuki 
Cc: "YAMAMOTO Takashi" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

CGroup API files: add cgroup map data type

2008-04-29T15:06:08+00:00

Adds a new type of supported control file representation, a map from strings
to u64 values.

Each map entry is printed as a line in a similar format to /proc/vmstat, i.e.
"$key $value\n"

Signed-off-by: Paul Menage 
Cc: "Li Zefan" 
Cc: Balbir Singh 
Cc: Paul Jackson 
Cc: Pavel Emelyanov 
Cc: KAMEZAWA Hiroyuki 
Cc: "YAMAMOTO Takashi" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

CGroup API files: rename read/write_uint methods to read_write_u64

2008-04-29T15:06:07+00:00

Several people have justifiably complained that the "_uint" suffix is
inappropriate for functions that handle u64 values, so this patch just renames
all these functions and their users to have the suffic _u64.

[peterz@infradead.org: build fix]
Signed-off-by: Paul Menage 
Cc: "Li Zefan" 
Cc: Balbir Singh 
Cc: Paul Jackson 
Cc: Pavel Emelyanov 
Cc: KAMEZAWA Hiroyuki 
Cc: "YAMAMOTO Takashi" 
Signed-off-by: Peter Zijlstra 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

cgroups: add cgroup support for enabling controllers at boot time

2008-04-04T21:46:26+00:00

The effects of cgroup_disable=foo are:

- foo isn't auto-mounted if you mount all cgroups in a single hierarchy
- foo isn't visible as an individually mountable subsystem

As a result there will only ever be one call to foo->create(), at init time;
all processes will stay in this group, and the group will never be mounted on
a visible hierarchy.  Any additional effects (e.g.  not allocating metadata)
are up to the foo subsystem.

This doesn't handle early_init subsystems (their "disabled" bit isn't set be,
but it could easily be extended to do so if any of the early_init systems
wanted it - I think it would just involve some nastier parameter processing
since it would occur before the command-line argument parser had been run.

Hugh said:

  Ballpark figures, I'm trying to get this question out rather than
  processing the exact numbers: CONFIG_CGROUP_MEM_RES_CTLR adds 15% overhead
  to the affected paths, booting with cgroup_disable=memory cuts that back to
  1% overhead (due to slightly bigger struct page).

  I'm no expert on distros, they may have no interest whatever in
  CONFIG_CGROUP_MEM_RES_CTLR=y; and the rest of us can easily build with or
  without it, or apply the cgroup_disable=memory patches.

Unix bench's execl test result on x86_64 was

== just after boot without mounting any cgroup fs.==
mem_cgorup=off : Execl Throughput       43.0     3150.1      732.6
mem_cgroup=on  : Execl Throughput       43.0     2932.6      682.0
==

[lizf@cn.fujitsu.com: fix boot option parsing]
Signed-off-by: Balbir Singh 
Cc: Paul Menage 
Cc: Balbir Singh 
Cc: Pavel Emelyanov 
Cc: KAMEZAWA Hiroyuki 
Cc: Hugh Dickins 
Cc: Sudhir Kumar 
Cc: YAMAMOTO Takashi 
Cc: David Rientjes 
Signed-off-by: Li Zefan 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds