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Commit Graph

152 Commits

Author SHA1 Message Date
Wanpeng Li
2b11a74b21 f2fs: don't need to collect dirty sit entries and flush journal when there's no dirty sit entries
Don't need to collect dirty sit entries and flush sit journal to sit
 entries when there's no dirty sit entries. This patch check dirty_sentries
 earlier just like flush_nat_entries.

Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com>
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-04-10 15:08:29 -07:00
Chao Yu
1dcc336b02 f2fs: enable rb-tree extent cache
This patch enables rb-tree based extent cache in f2fs.

When we mount with "-o extent_cache", f2fs will try to add recently accessed
page-block mappings into rb-tree based extent cache as much as possible, instead
of original one extent info cache.

By this way, f2fs can support more effective cache between dnode page cache and
disk. It will supply high hit ratio in the cache with fewer memory when dnode
page cache are reclaimed in environment of low memory.

Storage: Sandisk sd card 64g
1.append write file (offset: 0, size: 128M);
2.override write file (offset: 2M, size: 1M);
3.override write file (offset: 4M, size: 1M);
...
4.override write file (offset: 48M, size: 1M);
...
5.override write file (offset: 112M, size: 1M);
6.sync
7.echo 3 > /proc/sys/vm/drop_caches
8.read file (size:128M, unit: 4k, count: 32768)
(time dd if=/mnt/f2fs/128m bs=4k count=32768)

Extent Hit Ratio:
		before		patched
Hit Ratio	121 / 1071	1071 / 1071

Performance:
		before		patched
real    	0m37.051s	0m35.556s
user    	0m0.040s	0m0.026s
sys     	0m2.990s	0m2.251s

Memory Cost:
		before		patched
Tree Count:	0		1 (size: 24 bytes)
Node Count:	0		45 (size: 1440 bytes)

v3:
 o retest and given more details of test result.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-03-03 09:58:47 -08:00
Chao Yu
1a118ccfd6 f2fs: use spinlock for segmap_lock instead of rwlock
rwlock can provide better concurrency when there are much more readers than
writers because readers can hold the rwlock simultaneously.

But now, for segmap_lock rwlock in struct free_segmap_info, there is only one
reader 'mount' from below call path:
->f2fs_fill_super
  ->build_segment_manager
    ->build_dirty_segmap
      ->init_dirty_segmap
        ->find_next_inuse
          read_lock
          ...
          read_unlock

Now that our concurrency can not be improved since there is no other reader for
this lock, we do not need to use rwlock_t type for segmap_lock, let's replace it
with spinlock_t type.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-02-11 17:04:51 -08:00
Jaegeuk Kim
60a3b782b1 f2fs: avoid variable length array
Instead of using variable length array, this patch let preallocate memory for
them.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-02-11 17:04:50 -08:00
Jaegeuk Kim
f7ef9b83b5 f2fs: introduce macros to convert bytes and blocks in f2fs
This patch adds two macros for transition between byte and block offsets.
Currently, f2fs only supports 4KB blocks, so use the default size for now.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-02-11 17:04:48 -08:00
Jaegeuk Kim
bba681cbb2 f2fs: introduce a batched trim
This patch introduces a batched trimming feature, which submits split discard
commands.

This is to avoid long latency due to huge trim commands.
If fstrim was triggered ranging from 0 to the end of device, we should lock
all the checkpoint-related mutexes, resulting in very long latency.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-02-11 17:04:44 -08:00
Jaegeuk Kim
119ee91445 f2fs: split UMOUNT and FASTBOOT flags
This patch adds FASTBOOT flag into checkpoint as follows.

 - CP_UMOUNT_FLAG is set when system is umounted.
 - CP_FASTBOOT_FLAG is set when intermediate checkpoint having node summaries
   was done.

So, if you get CP_UMOUNT_FLAG from checkpoint, the system was umounted cleanly.
Instead, if there was sudden-power-off, you can get CP_FASTBOOT_FLAG or nothing.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-02-11 17:04:41 -08:00
Jaegeuk Kim
38aa0889b2 f2fs: align direct_io'ed data to section
This patch aligns the start block address of a file for direct io to the f2fs's
section size.

Some flash devices manage an over 4KB-sized page as a write unit, and if the
direct_io'ed data are written but not aligned to that unit, the performance can
be degraded due to the partial page copies.

Thus, since f2fs has a section that is well aligned to FTL units, we can align
the block address to the section size so that f2fs avoids this misalignment.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-01-09 17:02:27 -08:00
Jaegeuk Kim
e1509cf294 f2fs: clean up to remove parameter
This patch uses dn->data_blkaddr as a parameter for the destination block
address.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-01-09 17:02:26 -08:00
Changman Lee
b9a2c25207 f2fs: add block count by in-place-update in stat info
This patch adds block count by in-place-update in stat.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-01-09 17:02:25 -08:00
Jaegeuk Kim
9e4ded3f30 f2fs: activate f2fs_trace_pid
This patch activates f2fs_trace_pid.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-01-09 17:02:24 -08:00
Jaegeuk Kim
cf04e8eb55 f2fs: use f2fs_io_info to clean up messy parameters during IO path
This patch cleans up parameters on IO paths.
The key idea is to use f2fs_io_info adding a parameter, block address, and then
use this structure as parameters.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-01-09 17:02:23 -08:00
Chao Yu
3fa06d7bc9 f2fs: readahead contiguous current summary blocks in checkpoint
Let's add readahead code for reading contiguous compact/normal summary blocks
in checkpoint, then we will gain better performance in mount procedure.

Changes from v1
  o remove inappropriate 'unlikely' in npages_for_summary_flush.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-01-09 17:02:23 -08:00
Jaegeuk Kim
042b7816aa f2fs: remove unnecessary call to invalidate inmemory pages
Now we use inmemory pages for atomic write only and provide abort procedure,
we don't need to truncate them explicitly.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-01-09 17:02:22 -08:00
Jaegeuk Kim
d7bc2484b8 f2fs: fix small discards not to issue redundantly
The ckpt_valid_map and cur_valid_map are synced by seg_info_to_raw_sit.

In the case of small discards, the candidates are selected before sync,
while fitrim selects candidates after sync.

So, for small discards, we need to add candidates only just being obsoleted.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-01-09 17:02:22 -08:00
Jaegeuk Kim
1e84371ffe f2fs: change atomic and volatile write policies
This patch adds two new ioctls to release inmemory pages grabbed by atomic
writes.
 o f2fs_ioc_abort_volatile_write
  - If transaction was failed, all the grabbed pages and data should be written.
 o f2fs_ioc_release_volatile_write
  - This is to enhance the performance of PERSIST mode in sqlite.

In order to avoid huge memory consumption which causes OOM, this patch changes
volatile writes to use normal dirty pages, instead blocked flushing to the disk
as long as system does not suffer from memory pressure.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-01-09 17:02:22 -08:00
Jaegeuk Kim
70c640b1d6 f2fs: don't need to call lock_op and lock_page for abort
We don't need to call lock_op and lock_page at the aborting path.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-01-09 17:02:21 -08:00
Jaegeuk Kim
88a70a69c0 f2fs: fix wrong condition check to trigger f2fs_sync_fs
If there is not enough available memory, we need to trigger f2fs_sync_fs.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-01-09 17:02:21 -08:00
Jaegeuk Kim
8dcf2ff721 f2fs: count the number of inmemory pages
This patch adds counting # of inmemory pages in the page cache.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-12-08 10:35:15 -08:00
Jaegeuk Kim
0722b1011a f2fs: set page private for inmemory pages for truncation
The inmemory pages should be handled by invalidate_page since it needs to be
released int the truncation path.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-12-08 10:35:14 -08:00
Jaegeuk Kim
9be32d72be f2fs: do retry operations with cond_resched
This patch revists retrial paths in f2fs.
The basic idea is to use cond_resched instead of retrying from the very early
stage.

Suggested-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-12-08 10:35:05 -08:00
Jaegeuk Kim
0341845efc f2fs: fix livelock calling f2fs_iget during f2fs_evict_inode
In f2fs_evict_inode,
 commit_inmemory_pages
   f2fs_gc
     f2fs_iget
       iget_locked
         -> wait for inode free

Here, if the inode is same as the one to be evicted, f2fs should wait forever.
Actually, we should not call f2fs_balance_fs during f2fs_evict_inode to avoid
this.

But, the commit_inmem_pages calls f2fs_balance_fs by default, even if
f2fs_evict_inode wants to free inmemory pages only.

Hence, this patch adds to trigger f2fs_balance_fs only when there is something
to write.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-23 21:51:57 -08:00
Changman Lee
c9ee00857c f2fs: fix wrong data structure when create slab
It used nat_entry_set when create slab for sit_entry_set.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-23 21:48:49 -08:00
Jaegeuk Kim
e5e7ea3c86 f2fs: control the memory footprint used by ino entries
This patch adds to control the memory footprint used by ino entries.
This will conduct best effort, not strictly.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-06 15:24:46 -08:00
Jaegeuk Kim
a344b9fda0 f2fs: disable roll-forward when active_logs = 2
The roll-forward mechanism should be activated when the number of active
logs is not 2.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-05 20:05:53 -08:00
Jaegeuk Kim
adf4983bde f2fs: send discard commands in larger extent
If there is a chance to make a huge sized discard command, we don't need
to split it out, since each blkdev_issue_discard should wait one at a
time.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-04 17:34:13 -08:00
Jaegeuk Kim
e3fb1b794b f2fs: do not discard data protected by the previous checkpoint
We should not discard any data protected by the previous checkpoint all
the time.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-03 16:07:38 -08:00
Jaegeuk Kim
ca4b02eeed f2fs: call write_checkpoint under disabled gc
During the write_checkpoint, we should avoid f2fs_gc trigger to avoid any
filesystem consistency.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-03 16:07:37 -08:00
Gu Zheng
2cc2218611 f2fs: use current_sit_addr to replace the open code
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-03 16:07:37 -08:00
Gu Zheng
52aca07425 f2fs: rename f2fs_set/clear_bit to f2fs_test_and_set/clear_bit
Rename f2fs_set/clear_bit to f2fs_test_and_set/clear_bit, which mean
set/clear bit and return the old value, for better readability.

Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-03 16:07:36 -08:00
Jan Kara
9bd27ae4aa f2fs: avoid returning uninitialized value to userspace from f2fs_trim_fs()
If user specifies too low end sector for trimming, f2fs_trim_fs() will
use uninitialized value as a number of trimmed blocks and returns it to
userspace. Initialize number of trimmed blocks early to avoid the
problem.

Coverity-id: 1248809
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-03 16:07:35 -08:00
Jaegeuk Kim
4a257ed677 f2fs: avoid build warning
This patch removes build warning.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-03 16:07:30 -08:00
Jaegeuk Kim
cbcb2872e3 f2fs: invalidate inmemory page
If user truncates file's data, we should truncate inmemory pages too.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-03 16:07:29 -08:00
Jaegeuk Kim
34ba94bac9 f2fs: do not make dirty any inmemory pages
This patch let inmemory pages be clean all the time.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-03 16:07:29 -08:00
Jaegeuk Kim
88b88a6679 f2fs: support atomic writes
This patch introduces a very limited functionality for atomic write support.
In order to support atomic write, this patch adds two ioctls:
 o F2FS_IOC_START_ATOMIC_WRITE
 o F2FS_IOC_COMMIT_ATOMIC_WRITE

The database engine should be aware of the following sequence.
1. open
 -> ioctl(F2FS_IOC_START_ATOMIC_WRITE);
2. writes
  : all the written data will be treated as atomic pages.
3. commit
 -> ioctl(F2FS_IOC_COMMIT_ATOMIC_WRITE);
  : this flushes all the data blocks to the disk, which will be shown all or
  nothing by f2fs recovery procedure.
4. repeat to #2.

The IO pattens should be:

  ,- START_ATOMIC_WRITE                  ,- COMMIT_ATOMIC_WRITE
 CP | D D D D D D | FSYNC | D D D D | FSYNC ...
                      `- COMMIT_ATOMIC_WRITE

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-10-06 17:39:50 -07:00
Jaegeuk Kim
7cd8558baa f2fs: check the use of macros on block counts and addresses
This patch cleans up the existing and new macros for readability.

Rule is like this.

         ,-----------------------------------------> MAX_BLKADDR -,
         |  ,------------- TOTAL_BLKS ----------------------------,
         |  |                                                     |
         |  ,- seg0_blkaddr   ,----- sit/nat/ssa/main blkaddress  |
block    |  | (SEG0_BLKADDR)  | | | |   (e.g., MAIN_BLKADDR)      |
address  0..x................ a b c d .............................
            |                                                     |
global seg# 0...................... m .............................
            |                       |                             |
            |                       `------- MAIN_SEGS -----------'
            `-------------- TOTAL_SEGS ---------------------------'
                                    |                             |
 seg#                               0..........xx..................

= Note =
 o GET_SEGNO_FROM_SEG0 : blk address -> global segno
 o GET_SEGNO           : blk address -> segno
 o START_BLOCK         : segno -> starting block address

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-09-30 15:34:47 -07:00
Jaegeuk Kim
4b2fecc846 f2fs: introduce FITRIM in f2fs_ioctl
This patch introduces FITRIM in f2fs_ioctl.
In this case, f2fs will issue small discards and prefree discards as many as
possible for the given area.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-09-30 15:06:09 -07:00
Jaegeuk Kim
9b5f136fd4 f2fs: change the ipu_policy option to enable combinations
This patch changes the ipu_policy setting to use any combination of orthogonal policies.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-09-23 11:10:24 -07:00
Chao Yu
55cf9cb63f f2fs: support large sector size
Block size in f2fs is 4096 bytes, so theoretically, f2fs can support 4096 bytes
sector device at maximum. But now f2fs only support 512 bytes size sector, so
block device such as zRAM which uses page cache as its block storage space will
not be mounted successfully as mismatch between sector size of zRAM and sector
size of f2fs supported.

In this patch we support large sector size in f2fs, so block device with sector
size of 512/1024/2048/4096 bytes can be supported in f2fs.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-09-23 11:10:20 -07:00
Jaegeuk Kim
90a893c749 f2fs: use MAX_BIO_BLOCKS(sbi)
This patch cleans up a simple macro.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-09-23 11:10:18 -07:00
Jaegeuk Kim
c1ce1b02bb f2fs: give an option to enable in-place-updates during fsync to users
If user wrote F2FS_IPU_FSYNC:4 in /sys/fs/f2fs/ipu_policy, f2fs_sync_file
only starts to try in-place-updates.
And, if the number of dirty pages is over /sys/fs/f2fs/min_fsync_blocks, it
keeps out-of-order manner. Otherwise, it triggers in-place-updates.

This may be used by storage showing very high random write performance.

For example, it can be used when,

Seq. writes (Data) + wait + Seq. writes (Node)

is pretty much slower than,

Rand. writes (Data)

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-09-16 04:10:44 -07:00
Gu Zheng
721bd4d5c3 f2fs: use lock-less list(llist) to simplify the flush cmd management
We use flush cmd control to collect many flush cmds, and flush them
together. In this case, we use two list to manage the flush cmds
(collect and dispatch), and one spin lock is used to protect this.
In fact, the lock-less list(llist) is very suitable to this case,
and we use simplify this routine.

-
v2:
-use llist_for_each_entry_safe to fix possible use-after-free issue.
-remove the unused field from struct flush_cmd.
Thanks for Yu's suggestion.
-

Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-09-09 13:15:06 -07:00
Chao Yu
184a5cd2ce f2fs: refactor flush_sit_entries codes for reducing SIT writes
In commit aec71382c6 ("f2fs: refactor flush_nat_entries codes for reducing NAT
writes"), we descripte the issue as below:

"Although building NAT journal in cursum reduce the read/write work for NAT
block, but previous design leave us lower performance when write checkpoint
frequently for these cases:
1. if journal in cursum has already full, it's a bit of waste that we flush all
   nat entries to page for persistence, but not to cache any entries.
2. if journal in cursum is not full, we fill nat entries to journal util
   journal is full, then flush the left dirty entries to disk without merge
   journaled entries, so these journaled entries may be flushed to disk at next
   checkpoint but lost chance to flushed last time."

Actually, we have the same problem in using SIT journal area.

In this patch, firstly we will update sit journal with dirty entries as many as
possible. Secondly if there is no space in sit journal, we will remove all
entries in journal and walk through the whole dirty entry bitmap of sit,
accounting dirty sit entries located in same SIT block to sit entry set. All
entry sets are linked to list sit_entry_set in sm_info, sorted ascending order
by count of entries in set. Later we flush entries in set which have fewest
entries into journal as many as we can, and then flush dense set with merged
entries to disk.

In this way we can use sit journal area more effectively, also we will reduce
SIT update, result in gaining in performance and saving lifetime of flash
device.

In my testing environment, it shows this patch can help to reduce SIT block
update obviously.

virtual machine + hard disk:
fsstress -p 20 -n 400 -l 5
		sit page num	cp count	sit pages/cp
based		2006.50		1349.75		1.486
patched		1566.25		1463.25		1.070

Our latency of merging op is small when handling a great number of dirty SIT
entries in flush_sit_entries:
latency(ns)	dirty sit count
36038		2151
49168		2123
37174		2232

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-09-09 13:15:05 -07:00
Chao Yu
d3a14afd5e f2fs: remove unneeded sit_i in macro SIT_BLOCK_OFFSET/START_SEGNO
sit_i in macro SIT_BLOCK_OFFSET/START_SEGNO is not used, remove it.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-09-09 13:15:05 -07:00
Jaegeuk Kim
ec325b5270 f2fs: handle bug cases by letting fsck.f2fs initiate
This patch adds to handle corner buggy cases for fsck.f2fs.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-09-09 13:15:03 -07:00
Jaegeuk Kim
05796763b8 f2fs: add BUG cases to initiate fsck.f2fs
This patch replaces BUG cases with f2fs_bug_on to remain fsck.f2fs information.
And it implements some void functions to initiate fsck.f2fs too.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-09-09 13:15:03 -07:00
Jaegeuk Kim
9850cf4a89 f2fs: need fsck.f2fs when f2fs_bug_on is triggered
If any f2fs_bug_on is triggered, fsck.f2fs is needed.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-09-09 13:15:02 -07:00
Jaegeuk Kim
4081363fbe f2fs: introduce F2FS_I_SB, F2FS_M_SB, and F2FS_P_SB
This patch adds three inline functions to clean up dirty casting codes.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-09-03 17:37:13 -07:00
Jaegeuk Kim
202095a7a0 f2fs: remove rewrite_node_page
I think we need to let the dirty node pages remain in the page cache instead
of rewriting them in their places.
So, after done with successful recovery, write_checkpoint will flush all of them
through the normal write path.
Through this, we can avoid potential error cases in terms of block allocation.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-08-21 13:57:02 -07:00
arter97
e1c4204520 f2fs: fix typo
Fix typo and some grammatical errors.

The words "filesystem" and "readahead" are being used without the space treewide.

Signed-off-by: Park Ju Hyung <qkrwngud825@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-08-19 10:01:33 -07:00