---

yaml
---
r: 232372
b: refs/heads/master
c: bba9587
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 6d2ae89c36e2adab5cfa69fecb11290082817ac6
+refs/heads/master: bba958783b1b4cb0a9420f4e11082467132a334c

trunk/Documentation/cgroups/memory.txt

@@ -385,6 +385,10 @@ mapped_file	- # of bytes of mapped file (includes tmpfs/shmem)
 pgpgin		- # of pages paged in (equivalent to # of charging events).
 pgpgout		- # of pages paged out (equivalent to # of uncharging events).
 swap		- # of bytes of swap usage
+dirty		- # of bytes that are waiting to get written back to the disk.
+writeback	- # of bytes that are actively being written back to the disk.
+nfs_unstable	- # of bytes sent to the NFS server, but not yet committed to
+		the actual storage.
 inactive_anon	- # of bytes of anonymous memory and swap cache memory on
 		LRU list.
 active_anon	- # of bytes of anonymous and swap cache memory on active
@@ -406,6 +410,9 @@ total_mapped_file	- sum of all children's "cache"
 total_pgpgin		- sum of all children's "pgpgin"
 total_pgpgout		- sum of all children's "pgpgout"
 total_swap		- sum of all children's "swap"
+total_dirty		- sum of all children's "dirty"
+total_writeback		- sum of all children's "writeback"
+total_nfs_unstable	- sum of all children's "nfs_unstable"
 total_inactive_anon	- sum of all children's "inactive_anon"
 total_active_anon	- sum of all children's "active_anon"
 total_inactive_file	- sum of all children's "inactive_file"
@@ -453,6 +460,73 @@ memory under it will be reclaimed.
 You can reset failcnt by writing 0 to failcnt file.
 # echo 0 > .../memory.failcnt
 
+5.5 dirty memory
+
+Control the maximum amount of dirty pages a cgroup can have at any given time.
+
+Limiting dirty memory is like fixing the max amount of dirty (hard to reclaim)
+page cache used by a cgroup.  So, in case of multiple cgroup writers, they will
+not be able to consume more than their designated share of dirty pages and will
+be forced to perform write-out if they cross that limit.
+
+The interface is equivalent to the procfs interface: /proc/sys/vm/dirty_*.  It
+is possible to configure a limit to trigger both a direct writeback or a
+background writeback performed by per-bdi flusher threads.  The root cgroup
+memory.dirty_* control files are read-only and match the contents of
+the /proc/sys/vm/dirty_* files.
+
+Per-cgroup dirty limits can be set using the following files in the cgroupfs:
+
+- memory.dirty_ratio: the amount of dirty memory (expressed as a percentage of
+  cgroup memory) at which a process generating dirty pages will itself start
+  writing out dirty data.
+
+- memory.dirty_limit_in_bytes: the amount of dirty memory (expressed in bytes)
+  in the cgroup at which a process generating dirty pages will start itself
+  writing out dirty data.  Suffix (k, K, m, M, g, or G) can be used to indicate
+  that value is kilo, mega or gigabytes.
+
+  Note: memory.dirty_limit_in_bytes is the counterpart of memory.dirty_ratio.
+  Only one of them may be specified at a time.  When one is written it is
+  immediately taken into account to evaluate the dirty memory limits and the
+  other appears as 0 when read.
+
+- memory.dirty_background_ratio: the amount of dirty memory of the cgroup
+  (expressed as a percentage of cgroup memory) at which background writeback
+  kernel threads will start writing out dirty data.
+
+- memory.dirty_background_limit_in_bytes: the amount of dirty memory (expressed
+  in bytes) in the cgroup at which background writeback kernel threads will
+  start writing out dirty data.  Suffix (k, K, m, M, g, or G) can be used to
+  indicate that value is kilo, mega or gigabytes.
+
+  Note: memory.dirty_background_limit_in_bytes is the counterpart of
+  memory.dirty_background_ratio.  Only one of them may be specified at a time.
+  When one is written it is immediately taken into account to evaluate the dirty
+  memory limits and the other appears as 0 when read.
+
+A cgroup may contain more dirty memory than its dirty limit.  This is possible
+because of the principle that the first cgroup to touch a page is charged for
+it.  Subsequent page counting events (dirty, writeback, nfs_unstable) are also
+counted to the originally charged cgroup.
+
+Example: If page is allocated by a cgroup A task, then the page is charged to
+cgroup A.  If the page is later dirtied by a task in cgroup B, then the cgroup A
+dirty count will be incremented.  If cgroup A is over its dirty limit but cgroup
+B is not, then dirtying a cgroup A page from a cgroup B task may push cgroup A
+over its dirty limit without throttling the dirtying cgroup B task.
+
+When use_hierarchy=0, each cgroup has dirty memory usage and limits.
+System-wide dirty limits are also consulted.  Dirty memory consumption is
+checked against both system-wide and per-cgroup dirty limits.
+
+The current implementation does not enforce per-cgroup dirty limits when
+use_hierarchy=1.  System-wide dirty limits are used for processes in such
+cgroups.  Attempts to read memory.dirty_* files return the system-wide
+values.  Writes to the memory.dirty_* files return error.  An enhanced
+implementation is needed to check the chain of parents to ensure that no
+dirty limit is exceeded.
+
 6. Hierarchy support
 
 The memory controller supports a deep hierarchy and hierarchical accounting.

trunk/Documentation/device-mapper/dm-crypt.txt

@@ -8,7 +8,7 @@ Parameters: <cipher> <key> <iv_offset> <device path> <offset>
 
 <cipher>
     Encryption cipher and an optional IV generation mode.
-    (In format cipher-chainmode-ivopts:ivmode).
+    (In format cipher[:keycount]-chainmode-ivopts:ivmode).
     Examples:
        des
        aes-cbc-essiv:sha256
@@ -20,6 +20,11 @@ Parameters: <cipher> <key> <iv_offset> <device path> <offset>
     Key used for encryption. It is encoded as a hexadecimal number.
     You can only use key sizes that are valid for the selected cipher.
 
+<keycount>
+    Multi-key compatibility mode. You can define <keycount> keys and
+    then sectors are encrypted according to their offsets (sector 0 uses key0;
+    sector 1 uses key1 etc.).  <keycount> must be a power of two.
+
 <iv_offset>
     The IV offset is a sector count that is added to the sector number
     before creating the IV.

trunk/Documentation/device-mapper/dm-raid.txt

@@ -0,0 +1,70 @@
+Device-mapper RAID (dm-raid) is a bridge from DM to MD.  It
+provides a way to use device-mapper interfaces to access the MD RAID
+drivers.
+
+As with all device-mapper targets, the nominal public interfaces are the
+constructor (CTR) tables and the status outputs (both STATUSTYPE_INFO
+and STATUSTYPE_TABLE).  The CTR table looks like the following:
+
+1: <s> <l> raid \
+2:      <raid_type> <#raid_params> <raid_params> \
+3:      <#raid_devs> <meta_dev1> <dev1> .. <meta_devN> <devN>
+
+Line 1 contains the standard first three arguments to any device-mapper
+target - the start, length, and target type fields.  The target type in
+this case is "raid".
+
+Line 2 contains the arguments that define the particular raid
+type/personality/level, the required arguments for that raid type, and
+any optional arguments.  Possible raid types include: raid4, raid5_la,
+raid5_ls, raid5_rs, raid6_zr, raid6_nr, and raid6_nc.  (raid1 is
+planned for the future.)  The list of required and optional parameters
+is the same for all the current raid types.  The required parameters are
+positional, while the optional parameters are given as key/value pairs.
+The possible parameters are as follows:
+ <chunk_size>           Chunk size in sectors.
+ [[no]sync]             Force/Prevent RAID initialization
+ [rebuild <idx>]        Rebuild the drive indicated by the index
+ [daemon_sleep <ms>]    Time between bitmap daemon work to clear bits
+ [min_recovery_rate <kB/sec/disk>]      Throttle RAID initialization
+ [max_recovery_rate <kB/sec/disk>]      Throttle RAID initialization
+ [max_write_behind <sectors>]           See '-write-behind=' (man mdadm)
+ [stripe_cache <sectors>]               Stripe cache size for higher RAIDs
+
+Line 3 contains the list of devices that compose the array in
+metadata/data device pairs.  If the metadata is stored separately, a '-'
+is given for the metadata device position.  If a drive has failed or is
+missing at creation time, a '-' can be given for both the metadata and
+data drives for a given position.
+
+NB. Currently all metadata devices must be specified as '-'.
+
+Examples:
+# RAID4 - 4 data drives, 1 parity
+# No metadata devices specified to hold superblock/bitmap info
+# Chunk size of 1MiB
+# (Lines separated for easy reading)
+0 1960893648 raid \
+        raid4 1 2048 \
+        5 - 8:17 - 8:33 - 8:49 - 8:65 - 8:81
+
+# RAID4 - 4 data drives, 1 parity (no metadata devices)
+# Chunk size of 1MiB, force RAID initialization,
+#       min recovery rate at 20 kiB/sec/disk
+0 1960893648 raid \
+        raid4 4 2048 min_recovery_rate 20 sync\
+        5 - 8:17 - 8:33 - 8:49 - 8:65 - 8:81
+
+Performing a 'dmsetup table' should display the CTR table used to
+construct the mapping (with possible reordering of optional
+parameters).
+
+Performing a 'dmsetup status' will yield information on the state and
+health of the array.  The output is as follows:
+1: <s> <l> raid \
+2:      <raid_type> <#devices> <1 health char for each dev> <resync_ratio>
+
+Line 1 is standard DM output.  Line 2 is best shown by example:
+        0 1960893648 raid raid4 5 AAAAA 2/490221568
+Here we can see the RAID type is raid4, there are 5 devices - all of
+which are 'A'live, and the array is 2/490221568 complete with recovery.

trunk/Documentation/filesystems/proc.txt

@@ -375,6 +375,7 @@ Anonymous:             0 kB
 Swap:                  0 kB
 KernelPageSize:        4 kB
 MMUPageSize:           4 kB
+Locked:              374 kB
 
 The first of these lines shows the same information as is displayed for the
 mapping in /proc/PID/maps.  The remaining lines show the size of the mapping
@@ -670,6 +671,8 @@ varies by architecture and compile options.  The following is from a
 
 > cat /proc/meminfo
 
+The "Locked" indicates whether the mapping is locked in memory or not.
+
 
 MemTotal:     16344972 kB
 MemFree:      13634064 kB
@@ -1320,6 +1323,10 @@ scaled linearly with /proc/<pid>/oom_score_adj.
 Writing to /proc/<pid>/oom_score_adj or /proc/<pid>/oom_adj will change the
 other with its scaled value.
 
+The value of /proc/<pid>/oom_score_adj may be reduced no lower than the last
+value set by a CAP_SYS_RESOURCE process. To reduce the value any lower
+requires CAP_SYS_RESOURCE.
+
 NOTICE: /proc/<pid>/oom_adj is deprecated and will be removed, please see
 Documentation/feature-removal-schedule.txt.
 

trunk/Documentation/gpio.txt

@@ -135,7 +135,7 @@ setting up a platform_device using the GPIO, is mark its direction:
 	int gpio_direction_input(unsigned gpio);
 	int gpio_direction_output(unsigned gpio, int value);
 
-The return value is zero for success, else a negative errno.  It must
+The return value is zero for success, else a negative errno.  It should
 be checked, since the get/set calls don't have error returns and since
 misconfiguration is possible.  You should normally issue these calls from
 a task context.  However, for spinlock-safe GPIOs it's OK to use them