Commit graph

68 commits

Author SHA1 Message Date
Chao Yu
bae0ee7a76 f2fs: check PageWriteback flag for ordered case
For all ordered cases in f2fs_wait_on_page_writeback(), we need to
check PageWriteback status, so let's clean up to relocate the check
into f2fs_wait_on_page_writeback().

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-12-26 15:16:56 -08:00
Chao Yu
7c1a000d46 f2fs: add SPDX license identifiers
Remove the verbose license text from f2fs files and replace them with
SPDX tags.  This does not change the license of any of the code.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-09-12 13:07:10 -07:00
Chao Yu
fd8c8caf7e f2fs: let checkpoint flush dnode page of regular
Fsyncer will wait on all dnode pages of regular writeback before flushing,
if there are async dnode pages blocked by IO scheduler, it may decrease
fsync's performance.

In this patch, we choose to let f2fs_balance_fs_bg() to trigger checkpoint
to flush these dnode pages of regular, so async IO of dnode page can be
elimitnated, making fsyncer only need to wait for sync IO.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-08-01 11:52:36 -07:00
Weichao Guo
54c55c4e4f f2fs: support in-memory inode checksum when checking consistency
Enable in-memory inode checksum to protect metadata blocks from
in-memory scribbles when checking consistency, which has no
performance requirements.

Signed-off-by: Weichao Guo <guoweichao@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-07-27 18:03:59 +09:00
Chao Yu
780de47cf6 f2fs: don't track new nat entry in nat set
Nat entry set is used only in checkpoint(), and during checkpoint() we
won't flush new nat entry with unallocated address, so we don't need to
add new nat entry into nat set, then nat_entry_set::entry_cnt can
indicate actual entry count we need to flush in checkpoint().

Signed-off-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-03-27 20:10:29 -07:00
Chao Yu
c56675750d f2fs: remove unneeded set_cold_node()
When setting COLD_BIT_SHIFT flag in node block, we only need to call
set_cold_node() in new_node_page() and recover_inode_page() during
node page initialization. So remove unneeded set_cold_node() in other
places.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-03-17 13:57:33 +09:00
Jaegeuk Kim
f236792311 f2fs: allow to recover node blocks given updated checkpoint
If fsck.f2fs changes crc, we have no way to recover some inode blocks by roll-
forward recovery. Let's relax the condition to recover them.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-01-22 14:56:59 -08:00
Jaegeuk Kim
57864ae5ce f2fs: limit # of inmemory pages
If some abnormal users try lots of atomic write operations, f2fs is able to
produce pinned pages in the main memory which affects system performance.
This patch limits that as 20% over total memory size, and if f2fs reaches
to the limit, it will drop all the inmemory pages.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-10-26 10:44:21 +02:00
Chao Yu
9a4ffdf558 f2fs: obsolete ALLOC_NID_LIST list
As Fan Li reported, there is no user traversing nid_list[ALLOC_NID_LIST]
which is used for tracking preallocated nids. Let's drop it, and only
track preallocated nids in free_nid_root radix-tree.

Reported-by: Fan Li <fanofcode.li@samsung.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-10-10 12:49:53 -07:00
Fan Li
72fdbe2efe f2fs: simplify the way of calulating next nat address
The index of segment which the next nat block is in has only one different
bit than the current one, so to get the next nat address, we can simply
alter that one bit.

Signed-off-by: Fan Li <fanofcode.li@samsung.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-07-04 02:11:34 -07:00
Tomohiro Kusumi
68afcf2d38 f2fs: guard macro variables with braces
Add braces around variables used within macros for those make sense
to do it. Many of the macros in f2fs already do this. What this commit
doesn't do is anything that changes line# as a result of adding braces,
which usually affects the binary via __LINE__.

Confirmed no diff in fs/f2fs/f2fs.ko before/after this commit on x86_64,
to make sure this has no functional change as well as there's been no
unexpected side effect due to callers' arithmetics within the existing
code.

Signed-off-by: Tomohiro Kusumi <tkusumi@tuxera.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-10 19:48:10 -07:00
Fan Li
8a6aa32502 f2fs: adjust the way of calculating nat block
use a slightly simpler expression to calculate nat block with nid.

Signed-off-by: Fan Li <fanofcode.li@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-03-21 22:34:27 -04:00
Kinglong Mee
ced2c7ea8e f2fs: new helper cur_cp_crc() getting crc in f2fs_checkpoint
There are four places that getting the crc value in f2fs_checkpoint,
just add a new helper cur_cp_crc for them.

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 10:07:47 -08:00
Hou Pengyang
6bfaf7b150 f2fs: remove unsafe bitmap checking
proc A:                      proc B:
- writeback_sb_inodes
- __writeback_single_inode
- do_writepages
- f2fs_write_node_pages
- f2fs_balance_fs_bg         - write_checkpoint
- build_free_nids            - flush_nat_entries
- __build_free_nids          - __flush_nat_entry_set
- ra_meta_pages              - get_next_nat_page
- current_nat_addr           - set_to_next_nat
[do nat_bitmap checking]     - f2fs_change_bit

For proc A, nat_bitmap and nat_bitmap_mir would be compared without lock_op and
nm_i->nat_tree_lock, while proc B is changing nat_bitmap/nat_bitmap_ver in cp.

So it is normal for nat_bitmap/nat_bitmap diffrence under such scenario.

This patch fix this by removing the monitoring point.

[Fix: 599a09b f2fs: check in-memory nat version bitmap]
Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 09:59:51 -08:00
Chao Yu
d260081ccf f2fs: change recovery policy of xattr node block
Currently, if we call fsync after updating the xattr date belongs to the
file, f2fs needs to trigger checkpoint to keep xattr data consistent. But,
this policy cause low performance as checkpoint will block most foreground
operations and cause unneeded and unrelated IOs around checkpoint.

This patch will reuse regular file recovery policy for xattr node block,
so, we change to write xattr node block tagged with fsync flag to warm
area instead of cold area, and during recovery, we search warm node chain
for fsynced xattr block, and do the recovery.

So, for below application IO pattern, performance can be improved
obviously:
- touch file
- create/update/delete xattr entry in file
- fsync file

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-23 10:10:52 -08:00
Chao Yu
599a09b2c1 f2fs: check in-memory nat version bitmap
This patch adds a mirror for nat version bitmap, and use it to detect
in-memory bitmap corruption which may be caused by bit-transition of
cache or memory overflow.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-22 18:48:49 -08:00
Chao Yu
939afa943c f2fs: clean up with list_{first, last}_entry
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-22 18:48:47 -08:00
Chao Yu
b8559dc242 f2fs: split free nid list
During free nid allocation, in order to do preallocation, we will tag free
nid entry as allocated one and still leave it in free nid list, for other
allocators who want to grab free nids, it needs to traverse the free nid
list for lookup. It becomes overhead in scenario of allocating free nid
intensively by multithreads.

This patch splits free nid list to two list: {free,alloc}_nid_list, to
keep free nids and preallocated free nids separately, after that, traverse
latency will be gone, besides split nid_cnt for separate statistic.

Additionally, introduce __insert_nid_to_list and __remove_nid_from_list for
cleanup.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
[Jaegeuk Kim: modify f2fs_bug_on to avoid needless branches]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-11-23 12:11:00 -08:00
Eric Biggers
0c0b471e43 f2fs: fix sparse warnings
f2fs contained a number of endianness conversion bugs.

Also, one function should have been 'static'.

Found with sparse by running 'make C=2 CF=-D__CHECK_ENDIAN__ fs/f2fs/'

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-11-23 12:10:57 -08:00
Chao Yu
aaec2b1d18 f2fs: introduce cp_lock to protect updating of ckpt_flags
This patch introduces spinlock to protect updating process of ckpt_flags
field in struct f2fs_checkpoint, it avoids incorrectly updating in race
condition.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
[Jaegeuk Kim: add __is_set_ckpt_flags likewise __set_ckpt_flags]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-09-30 17:34:20 -07:00
Jaegeuk Kim
a468f0ef51 f2fs: use crc and cp version to determine roll-forward recovery
Previously, we used cp_version only to detect recoverable dnodes.
In order to avoid same garbage cp_version, we needed to truncate the next
dnode during checkpoint, resulting in additional discard or data write.
If we can distinguish this by using crc in addition to cp_version, we can
remove this overhead.

There is backward compatibility concern where it changes node_footer layout.
So, this patch introduces a new checkpoint flag, CP_CRC_RECOVERY_FLAG, to
detect new layout. New layout will be activated only when this flag is set.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-09-30 10:05:46 -07:00
Jaegeuk Kim
ad4edb8314 f2fs: produce more nids and reduce readahead nats
The readahead nat pages are more likely to be reclaimed quickly, so it'd better
to gather more free nids in advance.

And, let's keep some free nids as much as possible.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-07-06 10:44:08 -07:00
Jaegeuk Kim
e589c2c477 f2fs: control not to exceed # of cached nat entries
This is to avoid cache entry management overhead including radix tree.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-06-07 10:18:08 -07:00
Jaegeuk Kim
29710bcf94 f2fs: fix wrong percentage
This should be 1%, 10MB / 1GB.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-06-07 09:45:41 -07:00
Jaegeuk Kim
fec1d6576c f2fs: use wait_for_stable_page to avoid contention
In write_begin, if storage supports stable_page, we don't need to wait for
writeback to update its contents.
This patch introduces to use wait_for_stable_page instead of
wait_on_page_writeback.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-02-22 16:07:23 -08:00
Jaegeuk Kim
2049d4fcb0 f2fs: avoid multiple node page writes due to inline_data
The sceanrio is:
1. create fully node blocks
2. flush node blocks
3. write inline_data for all the node blocks again
4. flush node blocks redundantly

So, this patch tries to flush inline_data when flushing node blocks.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-02-22 16:07:23 -08:00
Chao Yu
2304cb0c44 f2fs: export dirty_nats_ratio in sysfs
This patch exports a new sysfs entry 'dirty_nat_ratio' to control threshold
of dirty nat entries, if current ratio exceeds configured threshold,
checkpoint will be triggered in f2fs_balance_fs_bg for flushing dirty nats.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-02-22 16:07:23 -08:00
Chao Yu
7d768d2c26 f2fs: flush dirty nat entries when exceeding threshold
When testing f2fs with xfstest, generic/251 is stuck for long time,
the case uses below serials to obtain fresh released space in device,
in order to prepare for following fstrim test.

1. rm -rf /mnt/dir
2. mkdir /mnt/dir/
3. cp -axT `pwd`/ /mnt/dir/
4. goto 1

During preparing step, all nat entries will be cached in nat cache,
most of them are dirty entries with invalid blkaddr, which means
nodes related to these entries have been truncated, and they could
be reused after the dirty entries been checkpointed.

However, there was no checkpoint been triggered, so nid allocators
(e.g. mkdir, creat) will run into long journey of iterating all NAT
pages, looking for free nids in alloc_nid->build_free_nids.

Here, in f2fs_balance_fs_bg we give another chance to do checkpoint
to flush nat entries for reusing them in free nid cache when dirty
entry count exceeds 10% of max count.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-02-22 16:07:23 -08:00
Jaegeuk Kim
12719ae14e f2fs: avoid unnecessary f2fs_balance_fs calls
Only when node page is newly dirtied, it needs to check whether we need to do
f2fs_gc.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-01-08 11:45:22 -08:00
Chao Yu
3519e3f992 f2fs: use sbi->blocks_per_seg to avoid unnecessary calculation
Use sbi->blocks_per_seg directly to avoid unnecessary calculation when using
1 << sbi->log_blocks_per_seg.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-04 12:07:57 -08:00
Chao Yu
ea1a29a0bd f2fs: export ra_nid_pages to sysfs
After finishing building free nid cache, we will try to readahead
asynchronously 4 more pages for the next reloading, the count of
readahead nid pages is fixed.

In some case, like SMR drive, read less sectors with fixed count
each time we trigger RA may be low efficient, since we will face
high seeking overhead, so we'd better let user to configure this
parameter from sysfs in specific workload.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-10-12 14:03:43 -07:00
Jaegeuk Kim
a125702326 Revert "f2fs: do not skip dentry block writes"
The periodic checkpoint can resolve the previous issue.
So, now we can use this again to improve the reported performance regression:

https://lkml.org/lkml/2015/10/8/20

This reverts commit 15bec0ff5a9ba6d203178fa8772259df6207942a.
2015-10-12 13:38:02 -07:00
Jaegeuk Kim
90b803e6fb f2fs: do not skip dentry block writes
Previously, we skip dentry block writes when wbc is SYNC_NONE with no memory
pressure and the number of dirty pages is pretty small.

But, we didn't skip for normal data writes, which gives us not much big impact
on overall performance.
Moreover, by skipping some data writes, kworker falls into infinite loop to try
to write blocks, when many dir inodes have only one dentry block.

So, this patch removes skipping data writes.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-10-09 16:20:54 -07:00
Jaegeuk Kim
b5492af78c f2fs: move existing definitions into f2fs.h
This patch moves some inode-related definitions from node.h to f2fs.h to
add new features.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:27 -07:00
Chao Yu
13054c548a f2fs: introduce infra macro and data structure of rb-tree extent cache
Introduce infra macro and data structure for rb-tree based extent cache:

Macros:
 * EXT_TREE_VEC_SIZE: indicate vector size for gang lookup in extent tree.
 * F2FS_MIN_EXTENT_LEN: indicate minimum length of extent managed in cache.
 * EXTENT_CACHE_SHRINK_NUMBER: indicate number of extent in cache will be shrunk.

Basic data structures for extent cache:
 * struct extent_tree: extent tree entry per inode.
 * struct extent_node: extent info node linked in extent tree.

Besides, adding new extent cache related fields in f2fs_sb_info.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-03-03 09:58:46 -08:00
Jaegeuk Kim
7aed0d4537 f2fs: free radix_tree_nodes used by nat_set entries
In the normal case, the radix_tree_nodes are freed successfully.
But, when cp_error was detected, we should destroy them forcefully.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-01-09 17:02:28 -08:00
Jaegeuk Kim
09eb483e89 f2fs: fix missing cold bit during recovery
In do_recover_data, we find and update previous node pages after updating
its new block addresses.
After then, we call fill_node_footer without reset field, we erase its
cold bit so that this new cold node block is written to wrong log area.
This patch fixes not to miss its old flag.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-01-09 17:02:25 -08:00
Chao Yu
5c27f4ee44 f2fs: merge two uchar variable in struct node_info to reduce memory cost
This patch moves one member of struct nat_entry: _flag_ to struct node_info,
so _version_ in struct node_info and _flag_ which are unsigned char type will
merge to one 32-bit space in register/memory. So the size of nat_entry will be
reduced from 28 bytes to 24 bytes (for 64-bit machine, reduce its size from 40
bytes to 32 bytes) and then slab memory using by f2fs will be reduced.

changes from v2:
 o update description of memory usage gain for 64-bit machine suggested by
   Changman Lee.
changes from v1:
 o introduce inline copy_node_info() to copy valid data from node info suggested
   by Jaegeuk Kim, it can avoid bug.

Reviewed-by: Changman Lee <cm224.lee@samsung.com>
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
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
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
Gu Zheng
c6ac4c0ec4 f2fs: introduce f2fs_change_bit to simplify the change bit logic
Introduce f2fs_change_bit to simplify the change bit logic in
function set_to_next_nat{sit}.

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
Jaegeuk Kim
120c2cba1d f2fs: remove unused return value
Don't return any value without any usage.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-10-05 21:05:15 -07:00
Jaegeuk Kim
309cc2b6e7 f2fs: refactor flush_nat_entries to remove costly reorganizing ops
Previously, f2fs tries to reorganize the dirty nat entries into multiple sets
according to its nid ranges. This can improve the flushing nat pages, however,
if there are a lot of cached nat entries, it becomes a bottleneck.

This patch introduces a new set management flow by removing dirty nat list and
adding a series of set operations when the nat entry becomes dirty.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-09-30 15:30:41 -07:00
Jaegeuk Kim
88bd02c947 f2fs: fix conditions to remain recovery information in f2fs_sync_file
This patch revisited whole the recovery information during the f2fs_sync_file.

In this patch, there are three information to make a decision.

a) IS_CHECKPOINTED,	/* is it checkpointed before? */
b) HAS_FSYNCED_INODE,	/* is the inode fsynced before? */
c) HAS_LAST_FSYNC,	/* has the latest node fsync mark? */

And, the scenarios for our rule are based on:

[Term] F: fsync_mark, D: dentry_mark

1. inode(x) | CP | inode(x) | dnode(F)
2. inode(x) | CP | inode(F) | dnode(F)
3. inode(x) | CP | dnode(F) | inode(x) | inode(F)
4. inode(x) | CP | dnode(F) | inode(F)
5. CP | inode(x) | dnode(F) | inode(DF)
6. CP | inode(DF) | dnode(F)
7. CP | dnode(F) | inode(DF)
8. CP | dnode(F) | inode(x) | inode(DF)

For example, #3, the three conditions should be changed as follows.

   inode(x) | CP | dnode(F) | inode(x) | inode(F)
a)    x       o      o          o          o
b)    x       x      x          x          o
c)    x       o      o          x          o

If f2fs_sync_file stops   ------^,
 it should write inode(F)    --------------^

So, the need_inode_block_update should return true, since
 c) get_nat_flag(e, HAS_LAST_FSYNC), is false.

For example, #8,
      CP | alloc | dnode(F) | inode(x) | inode(DF)
a)    o      x        x          x          x
b)    x               x          x          o
c)    o               o          x          o

If f2fs_sync_file stops   -------^,
 it should write inode(DF)    --------------^

Note that, the roll-forward policy should follow this rule, which means,
if there are any missing blocks, we doesn't need to recover that inode.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-09-23 11:10:15 -07:00
Jaegeuk Kim
7ef35e3b9e f2fs: introduce a flag to represent each nat entry information
This patch introduces a flag in the nat entry structure to merge various
information such as checkpointed and fsync_done marks.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-09-23 11:10:14 -07:00
Huang Ying
c6e489305e f2fs: fix a race condition in next_free_nid
The nm_i->fcnt checking is executed before spin_lock, so if another
thread delete the last free_nid from the list, the wrong nid may be
gotten.  So fix the race condition by moving the nm_i->fnct checking
into spin_lock.

Signed-off-by: Huang, Ying <ying.huang@intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-09-16 04:10:46 -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
Chao Yu
aec71382c6 f2fs: refactor flush_nat_entries codes for reducing NAT writes
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.

In this patch we merge dirty entries located in same NAT block to nat entry set,
and linked all set to list, sorted ascending order by entries' count of set.
Later we flush entries in sparse set into journal as many as we can, and then
flush merged entries to disk. In this way we can not only gain in performance,
but also save lifetime of flash device.

In my testing environment, it shows this patch can help to reduce NAT block
writes obviously. In hard disk test case: cost time of fsstress is stablely
reduced by about 5%.

1. virtual machine + hard disk:
fsstress -p 20 -n 200 -l 5
		node num	cp count	nodes/cp
based		4599.6		1803.0		2.551
patched		2714.6		1829.6		1.483

2. virtual machine + 32g micro SD card:
fsstress -p 20 -n 200 -l 1 -w -f chown=0 -f creat=4 -f dwrite=0
-f fdatasync=4 -f fsync=4 -f link=0 -f mkdir=4 -f mknod=4 -f rename=5
-f rmdir=5 -f symlink=0 -f truncate=4 -f unlink=5 -f write=0 -S

		node num	cp count	nodes/cp
based		84.5		43.7		1.933
patched		49.2		40.0		1.23

Our latency of merging op shows not bad when handling extreme case like:
merging a great number of dirty nats:
latency(ns)	dirty nat count
3089219		24922
5129423		27422
4000250		24523

change log from v1:
 o fix wrong logic in add_nat_entry when grab a new nat entry set.
 o swith to create slab cache in create_node_manager_caches.
 o use GFP_ATOMIC instead of GFP_NOFS to avoid potential long latency.

change log from v2:
 o make comment position more appropriate suggested by Jaegeuk Kim.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-07-09 14:04:25 -07:00
Zhang Zhen
8b376249e7 f2fs: fix checkpatch warning
fix the following checkpatch warning:
WARNING: do {} while (0) macros should not be semicolon terminated

Signed-off-by: Zhang Zhen <zhenzhang.zhang@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2014-05-07 10:21:59 +09:00
Jaegeuk Kim
54b591dfda f2fs: split grab_cache_page and wait_on_page_writeback for node pages
This patch splits grab_cache_page_write_begin into grab_cache_page and
wait_on_page_writeback for node pages.

This patch intends to enhance the latency to get node pages by alleviating
unnecessary wait_on_page_writeback.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2014-05-07 10:21:58 +09:00