Merge tag 'v3.0' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 into for-linus

1 files changed, 22 insertions, 19 deletions

diff --git a/Documentation/cgroups/blkio-controller.txt b/Documentation/cgroups/blkio-controller.txt
index 465351d4cf85..84f0a15fc210 100644
--- a/Documentation/cgroups/blkio-controller.txt
+++ b/Documentation/cgroups/blkio-controller.txt
@@ -28,16 +28,19 @@ cgroups. Here is what you can do.
 - Enable group scheduling in CFQ
         CONFIG_CFQ_GROUP_IOSCHED=y
 
-- Compile and boot into kernel and mount IO controller (blkio).
+- Compile and boot into kernel and mount IO controller (blkio); see
+  cgroups.txt, Why are cgroups needed?.
 
-        mount -t cgroup -o blkio none /cgroup
+        mount -t tmpfs cgroup_root /sys/fs/cgroup
+        mkdir /sys/fs/cgroup/blkio
+        mount -t cgroup -o blkio none /sys/fs/cgroup/blkio
 
 - Create two cgroups
-        mkdir -p /cgroup/test1/ /cgroup/test2
+        mkdir -p /sys/fs/cgroup/blkio/test1/ /sys/fs/cgroup/blkio/test2
 
 - Set weights of group test1 and test2
-        echo 1000 > /cgroup/test1/blkio.weight
-        echo 500 > /cgroup/test2/blkio.weight
+        echo 1000 > /sys/fs/cgroup/blkio/test1/blkio.weight
+        echo 500 > /sys/fs/cgroup/blkio/test2/blkio.weight
 
 - Create two same size files (say 512MB each) on same disk (file1, file2) and
   launch two dd threads in different cgroup to read those files.
@@ -46,12 +49,12 @@ cgroups. Here is what you can do.
         echo 3 > /proc/sys/vm/drop_caches
 
         dd if=/mnt/sdb/zerofile1 of=/dev/null &
-        echo $! > /cgroup/test1/tasks
-        cat /cgroup/test1/tasks
+        echo $! > /sys/fs/cgroup/blkio/test1/tasks
+        cat /sys/fs/cgroup/blkio/test1/tasks
 
         dd if=/mnt/sdb/zerofile2 of=/dev/null &
-        echo $! > /cgroup/test2/tasks
-        cat /cgroup/test2/tasks
+        echo $! > /sys/fs/cgroup/blkio/test2/tasks
+        cat /sys/fs/cgroup/blkio/test2/tasks
 
 - At macro level, first dd should finish first. To get more precise data, keep
   on looking at (with the help of script), at blkio.disk_time and
@@ -68,13 +71,13 @@ Throttling/Upper Limit policy
 - Enable throttling in block layer
         CONFIG_BLK_DEV_THROTTLING=y
 
-- Mount blkio controller
-        mount -t cgroup -o blkio none /cgroup/blkio
+- Mount blkio controller (see cgroups.txt, Why are cgroups needed?)
+        mount -t cgroup -o blkio none /sys/fs/cgroup/blkio
 
 - Specify a bandwidth rate on particular device for root group. The format
   for policy is "<major>:<minor>  <byes_per_second>".
 
-        echo "8:16  1048576" > /cgroup/blkio/blkio.read_bps_device
+        echo "8:16  1048576" > /sys/fs/cgroup/blkio/blkio.throttle.read_bps_device
 
   Above will put a limit of 1MB/second on reads happening for root group
   on device having major/minor number 8:16.
@@ -87,7 +90,7 @@ Throttling/Upper Limit policy
         1024+0 records out
         4194304 bytes (4.2 MB) copied, 4.0001 s, 1.0 MB/s
 
- Limits for writes can be put using blkio.write_bps_device file.
+ Limits for writes can be put using blkio.throttle.write_bps_device file.
 
 Hierarchical Cgroups
 ====================
@@ -108,7 +111,7 @@ Hierarchical Cgroups
   CFQ and throttling will practically treat all groups at same level.
 
                                 pivot
-                             /  |   \  \
+                             /  /   \  \
                         root  test1 test2  test3
 
   Down the line we can implement hierarchical accounting/control support
@@ -149,7 +152,7 @@ Proportional weight policy files
 
           Following is the format.
 
-          #echo dev_maj:dev_minor weight > /path/to/cgroup/blkio.weight_device
+          # echo dev_maj:dev_minor weight > blkio.weight_device
           Configure weight=300 on /dev/sdb (8:16) in this cgroup
           # echo 8:16 300 > blkio.weight_device
           # cat blkio.weight_device
@@ -283,28 +286,28 @@ Throttling/Upper limit policy files
           specified in bytes per second. Rules are per deivce. Following is
           the format.
 
-  echo "<major>:<minor>  <rate_bytes_per_second>" > /cgrp/blkio.read_bps_device
+  echo "<major>:<minor>  <rate_bytes_per_second>" > /cgrp/blkio.throttle.read_bps_device
 
 - blkio.throttle.write_bps_device
         - Specifies upper limit on WRITE rate to the device. IO rate is
           specified in bytes per second. Rules are per deivce. Following is
           the format.
 
-  echo "<major>:<minor>  <rate_bytes_per_second>" > /cgrp/blkio.write_bps_device
+  echo "<major>:<minor>  <rate_bytes_per_second>" > /cgrp/blkio.throttle.write_bps_device
 
 - blkio.throttle.read_iops_device
         - Specifies upper limit on READ rate from the device. IO rate is
           specified in IO per second. Rules are per deivce. Following is
           the format.
 
-  echo "<major>:<minor>  <rate_io_per_second>" > /cgrp/blkio.read_iops_device
+  echo "<major>:<minor>  <rate_io_per_second>" > /cgrp/blkio.throttle.read_iops_device
 
 - blkio.throttle.write_iops_device
         - Specifies upper limit on WRITE rate to the device. IO rate is
           specified in io per second. Rules are per deivce. Following is
           the format.
 
-  echo "<major>:<minor>  <rate_io_per_second>" > /cgrp/blkio.write_iops_device
+  echo "<major>:<minor>  <rate_io_per_second>" > /cgrp/blkio.throttle.write_iops_device
 
 Note: If both BW and IOPS rules are specified for a device, then IO is
       subjectd to both the constraints.