---

yaml
---
r: 116190
b: refs/heads/master
c: ed402af
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 40e24c403f325715f9c43b9fed2068641201ee0b
+refs/heads/master: ed402af3c23a4804b3f8899263e8d0f97c62ab49

trunk/.mailmap

@@ -66,6 +66,7 @@ Kenneth W Chen <kenneth.w.chen@intel.com>
 Koushik <raghavendra.koushik@neterion.com>
 Leonid I Ananiev <leonid.i.ananiev@intel.com>
 Linas Vepstas <linas@austin.ibm.com>
+Mark Brown <broonie@sirena.org.uk>
 Matthieu CASTET <castet.matthieu@free.fr>
 Michael Buesch <mb@bu3sch.de>
 Michael Buesch <mbuesch@freenet.de>

trunk/Documentation/cgroups/freezer-subsystem.txt

@@ -0,0 +1,99 @@
+	The cgroup freezer is useful to batch job management system which start
+and stop sets of tasks in order to schedule the resources of a machine
+according to the desires of a system administrator. This sort of program
+is often used on HPC clusters to schedule access to the cluster as a
+whole. The cgroup freezer uses cgroups to describe the set of tasks to
+be started/stopped by the batch job management system. It also provides
+a means to start and stop the tasks composing the job.
+
+	The cgroup freezer will also be useful for checkpointing running groups
+of tasks. The freezer allows the checkpoint code to obtain a consistent
+image of the tasks by attempting to force the tasks in a cgroup into a
+quiescent state. Once the tasks are quiescent another task can
+walk /proc or invoke a kernel interface to gather information about the
+quiesced tasks. Checkpointed tasks can be restarted later should a
+recoverable error occur. This also allows the checkpointed tasks to be
+migrated between nodes in a cluster by copying the gathered information
+to another node and restarting the tasks there.
+
+	Sequences of SIGSTOP and SIGCONT are not always sufficient for stopping
+and resuming tasks in userspace. Both of these signals are observable
+from within the tasks we wish to freeze. While SIGSTOP cannot be caught,
+blocked, or ignored it can be seen by waiting or ptracing parent tasks.
+SIGCONT is especially unsuitable since it can be caught by the task. Any
+programs designed to watch for SIGSTOP and SIGCONT could be broken by
+attempting to use SIGSTOP and SIGCONT to stop and resume tasks. We can
+demonstrate this problem using nested bash shells:
+
+	$ echo $$
+	16644
+	$ bash
+	$ echo $$
+	16690
+
+	From a second, unrelated bash shell:
+	$ kill -SIGSTOP 16690
+	$ kill -SIGCONT 16990
+
+	<at this point 16990 exits and causes 16644 to exit too>
+
+	This happens because bash can observe both signals and choose how it
+responds to them.
+
+	Another example of a program which catches and responds to these
+signals is gdb. In fact any program designed to use ptrace is likely to
+have a problem with this method of stopping and resuming tasks.
+
+	 In contrast, the cgroup freezer uses the kernel freezer code to
+prevent the freeze/unfreeze cycle from becoming visible to the tasks
+being frozen. This allows the bash example above and gdb to run as
+expected.
+
+	The freezer subsystem in the container filesystem defines a file named
+freezer.state. Writing "FROZEN" to the state file will freeze all tasks in the
+cgroup. Subsequently writing "THAWED" will unfreeze the tasks in the cgroup.
+Reading will return the current state.
+
+* Examples of usage :
+
+   # mkdir /containers/freezer
+   # mount -t cgroup -ofreezer freezer  /containers
+   # mkdir /containers/0
+   # echo $some_pid > /containers/0/tasks
+
+to get status of the freezer subsystem :
+
+   # cat /containers/0/freezer.state
+   THAWED
+
+to freeze all tasks in the container :
+
+   # echo FROZEN > /containers/0/freezer.state
+   # cat /containers/0/freezer.state
+   FREEZING
+   # cat /containers/0/freezer.state
+   FROZEN
+
+to unfreeze all tasks in the container :
+
+   # echo THAWED > /containers/0/freezer.state
+   # cat /containers/0/freezer.state
+   THAWED
+
+This is the basic mechanism which should do the right thing for user space task
+in a simple scenario.
+
+It's important to note that freezing can be incomplete. In that case we return
+EBUSY. This means that some tasks in the cgroup are busy doing something that
+prevents us from completely freezing the cgroup at this time. After EBUSY,
+the cgroup will remain partially frozen -- reflected by freezer.state reporting
+"FREEZING" when read. The state will remain "FREEZING" until one of these
+things happens:
+
+	1) Userspace cancels the freezing operation by writing "THAWED" to
+		the freezer.state file
+	2) Userspace retries the freezing operation by writing "FROZEN" to
+		the freezer.state file (writing "FREEZING" is not legal
+		and returns EIO)
+	3) The tasks that blocked the cgroup from entering the "FROZEN"
+		state disappear from the cgroup's set of tasks.

trunk/Documentation/controllers/memory.txt

@@ -112,14 +112,22 @@ the per cgroup LRU.
 
 2.2.1 Accounting details
 
-All mapped pages (RSS) and unmapped user pages (Page Cache) are accounted.
-RSS pages are accounted at the time of page_add_*_rmap() unless they've already
-been accounted for earlier. A file page will be accounted for as Page Cache;
-it's mapped into the page tables of a process, duplicate accounting is carefully
-avoided. Page Cache pages are accounted at the time of add_to_page_cache().
-The corresponding routines that remove a page from the page tables or removes
-a page from Page Cache is used to decrement the accounting counters of the
-cgroup.
+All mapped anon pages (RSS) and cache pages (Page Cache) are accounted.
+(some pages which never be reclaimable and will not be on global LRU
+ are not accounted. we just accounts pages under usual vm management.)
+
+RSS pages are accounted at page_fault unless they've already been accounted
+for earlier. A file page will be accounted for as Page Cache when it's
+inserted into inode (radix-tree). While it's mapped into the page tables of
+processes, duplicate accounting is carefully avoided.
+
+A RSS page is unaccounted when it's fully unmapped. A PageCache page is
+unaccounted when it's removed from radix-tree.
+
+At page migration, accounting information is kept.
+
+Note: we just account pages-on-lru because our purpose is to control amount
+of used pages. not-on-lru pages are tend to be out-of-control from vm view.
 
 2.3 Shared Page Accounting
 

trunk/Documentation/cpusets.txt

@@ -48,7 +48,7 @@ hooks, beyond what is already present, required to manage dynamic
 job placement on large systems.
 
 Cpusets use the generic cgroup subsystem described in
-Documentation/cgroup.txt.
+Documentation/cgroups/cgroups.txt.
 
 Requests by a task, using the sched_setaffinity(2) system call to
 include CPUs in its CPU affinity mask, and using the mbind(2) and

trunk/Documentation/filesystems/ext3.txt

@@ -96,6 +96,11 @@ errors=remount-ro(*)	Remount the filesystem read-only on an error.
 errors=continue		Keep going on a filesystem error.
 errors=panic		Panic and halt the machine if an error occurs.
 
+data_err=ignore(*)	Just print an error message if an error occurs
+			in a file data buffer in ordered mode.
+data_err=abort		Abort the journal if an error occurs in a file
+			data buffer in ordered mode.
+
 grpid			Give objects the same group ID as their creator.
 bsdgroups
 

trunk/Documentation/filesystems/proc.txt

@@ -1384,15 +1384,18 @@ causes the kernel to prefer to reclaim dentries and inodes.
 dirty_background_ratio
 ----------------------
 
-Contains, as a percentage of total system memory, the number of pages at which
-the pdflush background writeback daemon will start writing out dirty data.
+Contains, as a percentage of the dirtyable system memory (free pages + mapped
+pages + file cache, not including locked pages and HugePages), the number of
+pages at which the pdflush background writeback daemon will start writing out
+dirty data.
 
 dirty_ratio
 -----------------
 
-Contains, as a percentage of total system memory, the number of pages at which
-a process which is generating disk writes will itself start writing out dirty
-data.
+Contains, as a percentage of the dirtyable system memory (free pages + mapped
+pages + file cache, not including locked pages and HugePages), the number of
+pages at which a process which is generating disk writes will itself start
+writing out dirty data.
 
 dirty_writeback_centisecs
 -------------------------
@@ -2412,24 +2415,29 @@ will be dumped when the <pid> process is dumped. coredump_filter is a bitmask
 of memory types. If a bit of the bitmask is set, memory segments of the
 corresponding memory type are dumped, otherwise they are not dumped.
 
-The following 4 memory types are supported:
+The following 7 memory types are supported:
   - (bit 0) anonymous private memory
   - (bit 1) anonymous shared memory
   - (bit 2) file-backed private memory
   - (bit 3) file-backed shared memory
   - (bit 4) ELF header pages in file-backed private memory areas (it is
             effective only if the bit 2 is cleared)
+  - (bit 5) hugetlb private memory
+  - (bit 6) hugetlb shared memory
 
   Note that MMIO pages such as frame buffer are never dumped and vDSO pages
   are always dumped regardless of the bitmask status.
 
-Default value of coredump_filter is 0x3; this means all anonymous memory
-segments are dumped.
+  Note bit 0-4 doesn't effect any hugetlb memory. hugetlb memory are only
+  effected by bit 5-6.
+
+Default value of coredump_filter is 0x23; this means all anonymous memory
+segments and hugetlb private memory are dumped.
 
 If you don't want to dump all shared memory segments attached to pid 1234,
-write 1 to the process's proc file.
+write 0x21 to the process's proc file.
 
-  $ echo 0x1 > /proc/1234/coredump_filter
+  $ echo 0x21 > /proc/1234/coredump_filter
 
 When a new process is created, the process inherits the bitmask status from its
 parent. It is useful to set up coredump_filter before the program runs.

trunk/Documentation/kernel-parameters.txt

@@ -690,7 +690,7 @@ and is between 256 and 4096 characters. It is defined in the file
 			See Documentation/block/as-iosched.txt and
 			Documentation/block/deadline-iosched.txt for details.
 
-	elfcorehdr=	[X86-32, X86_64]
+	elfcorehdr=	[IA64,PPC,SH,X86-32,X86_64]
 			Specifies physical address of start of kernel core
 			image elf header. Generally kexec loader will
 			pass this option to capture kernel.