---

yaml
---
r: 140187
b: refs/heads/master
c: d9b9be0
h: refs/heads/master
i:
  140185: 2336081
  140183: b32e449
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 99360b4c18f7675b50d283301d46d755affe75fd
+refs/heads/master: d9b9be024a6628a01d8730d1fd0b5f25658a2794

trunk/Documentation/DocBook/.gitignore

@@ -4,3 +4,7 @@
 *.html
 *.9.gz
 *.9
+*.aux
+*.dvi
+*.log
+*.out

trunk/Documentation/RCU/listRCU.txt

@@ -118,7 +118,7 @@ Following are the RCU equivalents for these two functions:
 		list_for_each_entry(e, list, list) {
 			if (!audit_compare_rule(rule, &e->rule)) {
 				list_del_rcu(&e->list);
-				call_rcu(&e->rcu, audit_free_rule, e);
+				call_rcu(&e->rcu, audit_free_rule);
 				return 0;
 			}
 		}
@@ -206,7 +206,7 @@ RCU ("read-copy update") its name.  The RCU code is as follows:
 				ne->rule.action = newaction;
 				ne->rule.file_count = newfield_count;
 				list_replace_rcu(e, ne);
-				call_rcu(&e->rcu, audit_free_rule, e);
+				call_rcu(&e->rcu, audit_free_rule);
 				return 0;
 			}
 		}
@@ -283,7 +283,7 @@ flag under the spinlock as follows:
 				list_del_rcu(&e->list);
 				e->deleted = 1;
 				spin_unlock(&e->lock);
-				call_rcu(&e->rcu, audit_free_rule, e);
+				call_rcu(&e->rcu, audit_free_rule);
 				return 0;
 			}
 		}

trunk/Documentation/RCU/rcu.txt

@@ -81,7 +81,7 @@ o	I hear that RCU needs work in order to support realtime kernels?
 	This work is largely completed.  Realtime-friendly RCU can be
 	enabled via the CONFIG_PREEMPT_RCU kernel configuration parameter.
 	However, work is in progress for enabling priority boosting of
-	preempted RCU read-side critical sections.This is needed if you
+	preempted RCU read-side critical sections.  This is needed if you
 	have CPU-bound realtime threads.
 
 o	Where can I find more information on RCU?

trunk/Documentation/RCU/rculist_nulls.txt

@@ -21,7 +21,7 @@ if (obj) {
   /*
    * Because a writer could delete object, and a writer could
    * reuse these object before the RCU grace period, we
-   * must check key after geting the reference on object
+   * must check key after getting the reference on object
    */
   if (obj->key != key) { // not the object we expected
      put_ref(obj);
@@ -117,7 +117,7 @@ a race (some writer did a delete and/or a move of an object
 to another chain) checking the final 'nulls' value if
 the lookup met the end of chain. If final 'nulls' value
 is not the slot number, then we must restart the lookup at
-the begining. If the object was moved to same chain,
+the beginning. If the object was moved to the same chain,
 then the reader doesnt care : It might eventually
 scan the list again without harm.
 

trunk/Documentation/cgroups/cgroups.txt

@@ -333,12 +333,23 @@ The "xxx" is not interpreted by the cgroup code, but will appear in
 
 To mount a cgroup hierarchy with just the cpuset and numtasks
 subsystems, type:
-# mount -t cgroup -o cpuset,numtasks hier1 /dev/cgroup
+# mount -t cgroup -o cpuset,memory hier1 /dev/cgroup
 
 To change the set of subsystems bound to a mounted hierarchy, just
 remount with different options:
+# mount -o remount,cpuset,ns hier1 /dev/cgroup
 
-# mount -o remount,cpuset,ns  /dev/cgroup
+Now memory is removed from the hierarchy and ns is added.
+
+Note this will add ns to the hierarchy but won't remove memory or
+cpuset, because the new options are appended to the old ones:
+# mount -o remount,ns /dev/cgroup
+
+To Specify a hierarchy's release_agent:
+# mount -t cgroup -o cpuset,release_agent="/sbin/cpuset_release_agent" \
+  xxx /dev/cgroup
+
+Note that specifying 'release_agent' more than once will return failure.
 
 Note that changing the set of subsystems is currently only supported
 when the hierarchy consists of a single (root) cgroup. Supporting
@@ -349,6 +360,11 @@ Then under /dev/cgroup you can find a tree that corresponds to the
 tree of the cgroups in the system. For instance, /dev/cgroup
 is the cgroup that holds the whole system.
 
+If you want to change the value of release_agent:
+# echo "/sbin/new_release_agent" > /dev/cgroup/release_agent
+
+It can also be changed via remount.
+
 If you want to create a new cgroup under /dev/cgroup:
 # cd /dev/cgroup
 # mkdir my_cgroup
@@ -476,11 +492,13 @@ cgroup->parent is still valid. (Note - can also be called for a
 newly-created cgroup if an error occurs after this subsystem's
 create() method has been called for the new cgroup).
 
-void pre_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp);
+int pre_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp);
 
 Called before checking the reference count on each subsystem. This may
 be useful for subsystems which have some extra references even if
-there are not tasks in the cgroup.
+there are not tasks in the cgroup. If pre_destroy() returns error code,
+rmdir() will fail with it. From this behavior, pre_destroy() can be
+called multiple times against a cgroup.
 
 int can_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
 	       struct task_struct *task)

trunk/Documentation/cgroups/memcg_test.txt

@@ -1,5 +1,5 @@
 Memory Resource Controller(Memcg)  Implementation Memo.
-Last Updated: 2009/1/19
+Last Updated: 2009/1/20
 Base Kernel Version: based on 2.6.29-rc2.
 
 Because VM is getting complex (one of reasons is memcg...), memcg's behavior
@@ -360,3 +360,21 @@ Under below explanation, we assume CONFIG_MEM_RES_CTRL_SWAP=y.
 	# kill malloc task.
 
 	Of course, tmpfs v.s. swapoff test should be tested, too.
+
+ 9.8 OOM-Killer
+	Out-of-memory caused by memcg's limit will kill tasks under
+	the memcg. When hierarchy is used, a task under hierarchy
+	will be killed by the kernel.
+	In this case, panic_on_oom shouldn't be invoked and tasks
+	in other groups shouldn't be killed.
+
+	It's not difficult to cause OOM under memcg as following.
+	Case A) when you can swapoff
+	#swapoff -a
+	#echo 50M > /memory.limit_in_bytes
+	run 51M of malloc
+
+	Case B) when you use mem+swap limitation.
+	#echo 50M > memory.limit_in_bytes
+	#echo 50M > memory.memsw.limit_in_bytes
+	run 51M of malloc

trunk/Documentation/feature-removal-schedule.txt

@@ -255,6 +255,16 @@ Who:	Jan Engelhardt <jengelh@computergmbh.de>
 
 ---------------------------
 
+What:	GPIO autorequest on gpio_direction_{input,output}() in gpiolib
+When:	February 2010
+Why:	All callers should use explicit gpio_request()/gpio_free().
+	The autorequest mechanism in gpiolib was provided mostly as a
+	migration aid for legacy GPIO interfaces (for SOC based GPIOs).
+	Those users have now largely migrated.  Platforms implementing
+	the GPIO interfaces without using gpiolib will see no changes.
+Who:	David Brownell <dbrownell@users.sourceforge.net>
+---------------------------
+
 What:	b43 support for firmware revision < 410
 When:	The schedule was July 2008, but it was decided that we are going to keep the
         code as long as there are no major maintanance headaches.

trunk/Documentation/filesystems/exofs.txt

@@ -0,0 +1,176 @@
+===============================================================================
+WHAT IS EXOFS?
+===============================================================================
+
+exofs is a file system that uses an OSD and exports the API of a normal Linux
+file system. Users access exofs like any other local file system, and exofs
+will in turn issue commands to the local OSD initiator.
+
+OSD is a new T10 command set that views storage devices not as a large/flat
+array of sectors but as a container of objects, each having a length, quota,
+time attributes and more. Each object is addressed by a 64bit ID, and is
+contained in a 64bit ID partition. Each object has associated attributes
+attached to it, which are integral part of the object and provide metadata about
+the object. The standard defines some common obligatory attributes, but user
+attributes can be added as needed.
+
+===============================================================================
+ENVIRONMENT
+===============================================================================
+
+To use this file system, you need to have an object store to run it on.  You
+may download a target from:
+http://open-osd.org
+
+See Documentation/scsi/osd.txt for how to setup a working osd environment.
+
+===============================================================================
+USAGE
+===============================================================================
+
+1. Download and compile exofs and open-osd initiator:
+  You need an external Kernel source tree or kernel headers from your
+  distribution. (anything based on 2.6.26 or later).
+
+  a. download open-osd including exofs source using:
+     [parent-directory]$ git clone git://git.open-osd.org/open-osd.git
+
+  b. Build the library module like this:
+     [parent-directory]$ make -C KSRC=$(KER_DIR) open-osd
+
+     This will build both the open-osd initiator as well as the exofs kernel
+     module. Use whatever parameters you compiled your Kernel with and
+     $(KER_DIR) above pointing to the Kernel you compile against. See the file
+     open-osd/top-level-Makefile for an example.
+
+2. Get the OSD initiator and target set up properly, and login to the target.
+  See Documentation/scsi/osd.txt for farther instructions. Also see ./do-osd
+  for example script that does all these steps.
+
+3. Insmod the exofs.ko module:
+   [exofs]$ insmod exofs.ko
+
+4. Make sure the directory where you want to mount exists. If not, create it.
+   (For example, mkdir /mnt/exofs)
+
+5. At first run you will need to invoke the mkfs.exofs application
+
+   As an example, this will create the file system on:
+   /dev/osd0 partition ID 65536
+
+   mkfs.exofs --pid=65536 --format /dev/osd0
+
+   The --format is optional if not specified no OSD_FORMAT will be
+   preformed and a clean file system will be created in the specified pid,
+   in the available space of the target. (Use --format=size_in_meg to limit
+   the total LUN space available)
+
+   If pid already exist it will be deleted and a new one will be created in it's
+   place. Be careful.
+
+   An exofs lives inside a single OSD partition. You can create multiple exofs
+   filesystems on the same device using multiple pids.
+
+   (run mkfs.exofs without any parameters for usage help message)
+
+6. Mount the file system.
+
+   For example, to mount /dev/osd0, partition ID 0x10000 on /mnt/exofs:
+
+	mount -t exofs -o pid=65536 /dev/osd0 /mnt/exofs/
+
+7. For reference (See do-exofs example script):
+	do-exofs start - an example of how to perform the above steps.
+	do-exofs stop -  an example of how to unmount the file system.
+	do-exofs format - an example of how to format and mkfs a new exofs.
+
+8. Extra compilation flags (uncomment in fs/exofs/Kbuild):
+	CONFIG_EXOFS_DEBUG - for debug messages and extra checks.
+
+===============================================================================
+exofs mount options
+===============================================================================
+Similar to any mount command:
+	mount -t exofs -o exofs_options /dev/osdX mount_exofs_directory
+
+Where:
+    -t exofs: specifies the exofs file system
+
+    /dev/osdX: X is a decimal number. /dev/osdX was created after a successful
+               login into an OSD target.
+
+    mount_exofs_directory: The directory to mount the file system on
+
+    exofs specific options: Options are separated by commas (,)
+		pid=<integer> - The partition number to mount/create as
+                                container of the filesystem.
+                                This option is mandatory
+                to=<integer>  - Timeout in ticks for a single command
+                                default is (60 * HZ) [for debugging only]
+
+===============================================================================
+DESIGN
+===============================================================================
+
+* The file system control block (AKA on-disk superblock) resides in an object
+  with a special ID (defined in common.h).
+  Information included in the file system control block is used to fill the
+  in-memory superblock structure at mount time. This object is created before
+  the file system is used by mkexofs.c It contains information such as:
+	- The file system's magic number
+	- The next inode number to be allocated
+
+* Each file resides in its own object and contains the data (and it will be
+  possible to extend the file over multiple objects, though this has not been
+  implemented yet).
+
+* A directory is treated as a file, and essentially contains a list of <file
+  name, inode #> pairs for files that are found in that directory. The object
+  IDs correspond to the files' inode numbers and will be allocated according to
+  a bitmap (stored in a separate object). Now they are allocated using a
+  counter.
+
+* Each file's control block (AKA on-disk inode) is stored in its object's
+  attributes. This applies to both regular files and other types (directories,
+  device files, symlinks, etc.).
+
+* Credentials are generated per object (inode and superblock) when they is
+  created in memory (read off disk or created). The credential works for all
+  operations and is used as long as the object remains in memory.
+
+* Async OSD operations are used whenever possible, but the target may execute
+  them out of order. The operations that concern us are create, delete,
+  readpage, writepage, update_inode, and truncate. The following pairs of
+  operations should execute in the order written, and we need to prevent them
+  from executing in reverse order:
+	- The following are handled with the OBJ_CREATED and OBJ_2BCREATED
+	  flags. OBJ_CREATED is set when we know the object exists on the OSD -
+	  in create's callback function, and when we successfully do a read_inode.
+	  OBJ_2BCREATED is set in the beginning of the create function, so we
+	  know that we should wait.
+		- create/delete: delete should wait until the object is created
+		  on the OSD.
+		- create/readpage: readpage should be able to return a page
+		  full of zeroes in this case. If there was a write already
+		  en-route (i.e. create, writepage, readpage) then the page
+		  would be locked, and so it would really be the same as
+		  create/writepage.
+		- create/writepage: if writepage is called for a sync write, it
+		  should wait until the object is created on the OSD.
+		  Otherwise, it should just return.
+		- create/truncate: truncate should wait until the object is
+		  created on the OSD.
+		- create/update_inode: update_inode should wait until the
+		  object is created on the OSD.
+	- Handled by VFS locks:
+		- readpage/delete: shouldn't happen because of page lock.
+		- writepage/delete: shouldn't happen because of page lock.
+		- readpage/writepage: shouldn't happen because of page lock.
+
+===============================================================================
+LICENSE/COPYRIGHT
+===============================================================================
+The exofs file system is based on ext2 v0.5b (distributed with the Linux kernel
+version 2.6.10).  All files include the original copyrights, and the license
+is GPL version 2 (only version 2, as is true for the Linux kernel).  The
+Linux kernel can be downloaded from www.kernel.org.