Merge pull request #55 from Rover-Yu/master

backport the remaining part of SO_REUSEPORT features
config: add missing CONFIG_EXT4_FS_SUBTREE in kernel config file

After applied ext4 subtree id patch, we need to update kernel config
file to enable it.  But currently there is not CONFIG_EXT4_FS_SUBTREE
entry in kernel config file.  So fix it.

Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
mm: compaction: fix special case -1 order checks

Prevent division-by-zero panic when compaction was explicitely
requested through the procfs knob: /proc/sys/vm/compact_memory.

Backport from updtream commits 82478fb7 and 3957c776.

Signed-off-by: Sha Zhengju <handai.szj@taobao.com>
Merge pull request #56 from gnehzuil/enable-ext4-subtree

config: add missing CONFIG_EXT4_FS_SUBTREE in kernel config file
mm: compaction: add compaction sysctl

Add a new sysctl to enable/disable memory compaction and
the default is enabled.

Signed-off-by: Sha Zhengju <handai.szj@taobao.com>
Merge pull request #58 from shazj99/compaction

Memory compaction enhancement
Backport "mm: export generic_pipe_buf_*() to modules" to prefare for
LTTng support

commit f0d902f497ee2fb747086322a31925c7fb351d7a
Author: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date:   Sat Sep 1 17:47:36 2012 -0700

    mm: export generic_pipe_buf_*() to modules

    Backport for 2.6.32.x to 2.6.34.x of commits:

    commit 51921cb746f56983db5a373ca68deb2b0d3ddf01
    Author: Miklos Szeredi <mszeredi@suse.cz>
    Date:   Wed May 26 08:44:22 2010 +0200

        mm: export generic_pipe_buf_*() to modules

        This is needed by fuse device code which wants to create pipe
buffers.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Backport-by: Ren Zhen Yu <zhenyu.ren@aliyun-inc.com>
Backport "tracing: Let tracepoints have data passed to tracepoint
callbacks" for LTTng kmods support

Total, this patch backport v2.6.35 tracepoint ABI/API to taobao kernel,
which is the reason of odd names like kabi_2635_tracepoint_*().

The information of original commit is:

commit 2c2a566b64b4254c530fb0c2222b30e8a739bac9
Author: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date:   Sat Sep 1 17:45:09 2012 -0700

    tracing: Let tracepoints have data passed to tracepoint callbacks

    Backport of commit 38516ab59fbc5b3bb278cf5e1fe2867c70cff32e for
    2.6.32.x and 2.6.33.x. Keeping kABI compatibility.

    Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Backport-by: Ren Zhen Yu <zhenyu.ren@aliyun-inc.com>