Commit Graph

52 Commits

Author SHA1 Message Date
Jaegeuk Kim
b29555505d f2fs: add key functions for small discards
This patch adds key functions to activate the small discard feature.

Note that this procedure is conducted during the checkpoint only.

In flush_sit_entries(), when a new dirty sit entry is flushed, f2fs calls
add_discard_addrs() which searches candidates to be discarded.
The candidates should be marked *invalidated* and also previous checkpoint
recognizes it as *valid*.

At the end of a checkpoint procedure, f2fs throws discards based on the
discard entry list.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-12-23 10:18:00 +09:00
Jaegeuk Kim
7fd9e544fb f2fs: add a slab cache entry for small discards
This patch adds a slab cache entry for small discards.

Each entry consists of:

struct discard_entry {
	struct list_head list;	/* list head */
	block_t blkaddr;	/* block address to be discarded */
	int len;		/* # of consecutive blocks of the discard */
};

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-12-23 10:18:00 +09:00
Changman Lee
e81c93cf8c f2fs: improve searching speed of __next_free_blkoff
To find a zero bit using the result of OR operation between ckpt_valid_map
and cur_valid_map is more fast than find a zero bit in each bitmap.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
[Jaegeuk Kim: adjust changed function name]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-12-23 10:17:59 +09:00
Changman Lee
9a7f143ab5 f2fs: introduce __find_rev_next(_zero)_bit
When f2fs_set_bit is used, in a byte MSB and LSB is reversed,
in that case we can use __find_rev_next_bit or __find_rev_next_zero_bit.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
[Jaegeuk Kim: change the function names]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-12-23 10:17:59 +09:00
Changman Lee
29e59c14ae f2fs: issue more large discard command
o Changes from v1
  Use find_next(_zero)_bit suggested by jg.kim

When f2fs issues discard command, if segment is contiguous,
let's issue more large segment to gather adjacent segments.

** blktrace **
179,1    0     5859    42.619023770   971  C   D 131072 + 2097152 [0]
179,1    0    33665   108.840475468   971  C   D 2228224 + 2494464 [0]
179,1    0    33671   109.131616427   971  C   D 14909440 + 344064 [0]
179,1    0    33677   109.137100677   971  C   D 15261696 + 4096 [0]

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-11-11 09:36:32 +09:00
Changman Lee
fb51b5ef9c f2fs: cleanup waiting routine for writeback pages in cp
use genernal method supported by kernel

 o changes from v1
   If any waiter exists at end io, wake up it.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-11-08 14:10:29 +09:00
Chao Yu
3b03f72445 f2fs: avoid to use a NULL point in destroy_segment_manager
A NULL point should avoid to be used in destroy_segment_manager after allocating
memory fail for f2fs_sm_info.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-11-06 16:37:44 +09:00
Fan Li
9a47938b22 f2fs: change the method of calculating the number summary blocks
npages_for_summary_flush uses (SUMMARY_SIZE + 1) as the size of a f2fs_summary
while its actual size is  SUMMARY_SIZE. So the result sometimes is bigger than
actual number by one, which causes checkpoint can't be written into disk
contiguously, and sometimes summary blocks can't be compacted like they should.
Besides, when writing summary blocks into pages, if remain space in a page
isn't big enough for one f2fs_summary, it will be left unused, current code
seems not to take it into account.

Signed-off-by: Fan Li <fanofcode.li@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-30 12:17:58 +09:00
Jaegeuk Kim
5d56b6718a f2fs: add an option to avoid unnecessary BUG_ONs
If you want to remove unnecessary BUG_ONs, you can just turn off F2FS_CHECK_FS
in your kernel config.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-29 15:44:38 +09:00
Changman Lee
4625d6aac2 f2fs: remove unnecessary segment bitmap updates
Only one dirty type is set in __locate_dirty_segment and we can know
dirty type of segment. So we don't need to check other dirty types.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-28 13:38:16 +09:00
Chao Yu
e8d61a7488 f2fs: remove redundant set_page_dirty from write_compacted_summaries
Previously, set_page_dirty is called every time after writting one summary info
into compacted summary page,
To avoid redundant set_page_dirty, we only call set_page_dirty before release
page.

Signed-off-by: Yu Chao <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-25 16:54:39 +09:00
Jaegeuk Kim
4660f9c0fe f2fs: introduce f2fs_balance_fs_bg for some background jobs
This patch merges some background jobs into this new function.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-25 16:54:38 +09:00
Jaegeuk Kim
81eb8d6e28 f2fs: reclaim prefree segments periodically
Previously, f2fs postpones reclaiming prefree segments into free segments
as much as possible.
However, if user writes and deletes a bunch of data without any sync or fsync
calls, some flash storages can suffer from garbage collections.

So, this patch adds the reclaiming codes to f2fs_write_node_pages and background
GC thread.

If there are a lot of prefree segments, let's do checkpoint so that f2fs
submits discard commands for the prefree regions to the flash storage.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-25 16:54:37 +09:00
Jaegeuk Kim
dcdfff6527 f2fs: clean up several status-related operations
This patch cleans up improper definitions that update some status information.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-25 16:54:08 +09:00
Haicheng Li
435f2a1b58 f2fs: no need to check other dirty_segmap when the seg has been found
Because one dirty seg can only be mapped to one dirty_type. Otherwise, it's a bug.

Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
[Jaegeuk Kim: modify a comment related to this patch]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-22 19:57:31 +09:00
Haicheng Li
cffbfa6648 f2fs: use true and false for boolean value
Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-22 19:49:39 +09:00
Gu Zheng
e234088758 f2fs: avoid wait if IO end up when do_checkpoint for better performance
Previously, do_checkpoint() will call congestion_wait() for waiting the pages
(previous submitted node/meta/data pages) to be written back.
Because congestion_wait() will set a regular period (e.g. HZ / 50 ) for waiting, and
no additional wake up mechanism was introduced if IO ends up before regular period costed.
Yuan Zhong found there is a situation that after the pages have been written back,
but the checkpoint thread still wait for congestion_wait to exit.

So here we store checkpoint task into f2fs_sb when doing checkpoint, it'll wait for IO completes
if there's IO going on, and in the end IO path, wake up checkpoint task when IO ends up.

Thanks to Yuan Zhong's pre work about this problem.

Reported-by: Yuan Zhong <yuan.mark.zhong@samsung.com>
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-18 09:44:14 +09:00
Chao Yu
cc7b1bb173 f2fs: avoid allocating failure in bio_alloc
This patch add macro MAX_BIO_BLOCKS to limit value of npages in
f2fs_bio_alloc, it can avoid allocating failure in bio_alloc caused by
npages is larger than BIO_MAX_PAGES.

Signed-off-by: Yu Chao <chao2.yu@samsung.com>
Reviewed-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-09-24 17:45:48 +09:00
Gu Zheng
7b40527508 f2fs: fix a compound statement label error
An error "label at end of compound statement" will occur if CONFIG_F2FS_STAT_FS
disabled.
fs/f2fs/segment.c:556:1: error: label at end of compound statement
So clean up the 'out' label to fix it.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-08-19 11:51:08 +09:00
Gu Zheng
41dfde135f f2fs: clean up the needless end 'return' of void function
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-08-12 11:49:22 +09:00
Jin Xu
a569469e96 f2fs: fix a deadlock in fsync
This patch fixes a deadlock bug that occurs quite often when there are
concurrent write and fsync on a same file.

Following is the simplified call trace when tasks get hung.

fsync thread:
- f2fs_sync_file
 ...
 - f2fs_write_data_pages
 ...
  - update_extent_cache
  ...
   - update_inode
    - wait_on_page_writeback

bdi writeback thread
- __writeback_single_inode
 - f2fs_write_data_pages
  - mutex_lock(sbi->writepages)

The deadlock happens when the fsync thread waits on a inode page that has
been added to the f2fs' cached bio sbi->bio[NODE], and unfortunately,
no one else could be able to submit the cached bio to block layer for
writeback. This is because the fsync thread already hold a sbi->fs_lock and
the sbi->writepages lock, causing the bdi thread being blocked when attempt
to write data pages for the same inode. At the same time, f2fs_gc thread
does not notice the situation and could not help. Even the sync syscall
gets blocked.

To fix it, we could submit the cached bio first before waiting on a inode page
that is being written back.

Signed-off-by: Jin Xu <jinuxstyle@gmail.com>
[Jaegeuk Kim: add more cases to use f2fs_wait_on_page_writeback]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-08-06 22:00:36 +09:00
Gu Zheng
d8207f6958 f2fs: move bio_private allocation out of f2fs_bio_alloc()
bio->bi_private is not always needed. As in the reading data path,
end_read_io does not need bio_private for further using, so moving
bio_private allocation out of f2fs_bio_alloc(). Alloc it in the
submit_write_page(), and ignore it in the f2fs_readpage().

Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-07-30 15:17:03 +09:00
Jaegeuk Kim
763bfe1bc5 f2fs: remove reusing any prefree segments
This patch removes check_prefree_segments initially designed to enhance the
performance by narrowing the range of LBA usage across the whole block device.

When allocating a new segment, previous f2fs tries to find proper prefree
segments, and then, if finds a segment, it reuses the segment for further
data or node block allocation.

However, I found that this was totally wrong approach since the prefree segments
have several data or node blocks that will be used by the roll-forward mechanism
operated after sudden-power-off.

Let's assume the following scenario.

/* write 8MB with fsync */
for (i = 0; i < 2048; i++) {
	offset = i * 4096;
	write(fd, offset, 4KB);
	fsync(fd);
}

In this case, naive segment allocation sequence will be like:
 data segment: x, x+1, x+2, x+3
 node segment: y, y+1, y+2, y+3.

But, if we can reuse prefree segments, the sequence can be like:
 data segment: x, x+1, y, y+1
 node segment: y, y+1, y+2, y+3.
Because, y, y+1, and y+2 became prefree segments one by one, and those are
reused by data allocation.

After conducting this workload, we should consider how to recover the latest
inode with its data.
If we reuse the prefree segments such as y or y+1, we lost the old node blocks
so that f2fs even cannot start roll-forward recovery.

Therefore, I suggest that we should remove reusing prefree segments.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-07-02 08:48:15 +09:00
Namjae Jeon
8736fbf003 f2fs: optimize the init_dirty_segmap function
Optimize the while loop condition

Since this condition will always be true and while loop will
be terminated by the following condition in code:

if (segno >= TOTAL_SEGS(sbi))
    break;
Hence we can replace the while loop condition with while(1)
instead of always checking for segno to be less than Total segs.

Also we do not need to use TOTAL_SEGS() everytime. We can store
this value in a local variable since this value is constant.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Pankaj Kumar <pankaj.km@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-07-02 08:48:14 +09:00
Jaegeuk Kim
354a3399dc f2fs: recover wrong pino after checkpoint during fsync
If a file is linked, f2fs loose its parent inode number so that fsync calls
for the linked file should do checkpoint all the time.
But, if we can recover its parent inode number after the checkpoint, we can
adjust roll-forward mechanism for the further fsync calls, which is able to
improve the fsync performance significatly.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-06-14 09:04:45 +09:00
Haicheng Li
8d8451af68 f2fs: make locate_dirty_segment() as static
It's used only locally and could be static.

Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-06-14 09:04:44 +09:00
Haicheng Li
e79efe3b69 f2fs: remove unnecessary parameter "offset" from __add_sum_entry()
We can get the value directly from pointer "curseg".

Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-06-14 09:04:43 +09:00
Namjae Jeon
35b09d82c3 f2fs: push some variables to debug part
Some, counters are needed only for the statistical information
while debugging.
So, those can be controlled using CONFIG_F2FS_STAT_FS,
pushing the usage for few variables under this flag.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-05-28 15:03:05 +09:00
Haicheng Li
81fb5e8746 f2fs: remove unecessary variable and code
Code cleanup without behavior changed.

Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-05-28 15:03:02 +09:00
Jaegeuk Kim
ac5d156c78 f2fs: modify the number of issued pages to merge IOs
When testing f2fs on an SSD, I found some 128 page IOs followed by 1 page IO
were issued by f2fs_write_node_pages.
This means that there were some mishandling flows which degrades performance.

Previous f2fs_write_node_pages determines the number of pages to be written,
nr_to_write, as follows.

1. The bio_get_nr_vecs returns 129 pages.
2. The bio_alloc makes a room for 128 pages.
3. The initial 128 pages go into one bio.
4. The existing bio is submitted, and a new bio is prepared for the last 1 page.
5. Finally, sync_node_pages submits the last 1 page bio.

The problem is from the use of bio_get_nr_vecs, so this patch replace it
with max_hw_blocks using queue_max_sectors.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-30 12:07:32 +09:00
Namjae Jeon
8680441caa f2fs: add REQ_META about metadata requests for submit
Adding REQ_META for all the metadata requests can help in improving the
FS performance, if the underlying device supports TAGGING.
So, when considering the submit_bio path for all the f2fs requests. We can
add REQ_META for all the META requests.
As a precursor to this change we considered the commit
4265900e0b 'mmc: MMC-4.5 Data Tag Support'

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-26 10:35:11 +09:00
Namjae Jeon
6ec178dac6 f2fs: add tracepoints for write page operations
Add tracepoints to debug the various page write operation
like data pages, meta pages.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Pankaj Kumar <pankaj.km@samsung.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
[Jaegeuk: remove unnecessary tracepoints]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-23 18:15:17 +09:00
Jaegeuk Kim
b2f2c390c5 f2fs: fix the bitmap consistency of dirty segments
Like below, there are 8 segment bitmaps for SSR victim candidates.

enum dirty_type {
	DIRTY_HOT_DATA,		/* dirty segments assigned as hot data logs */
	DIRTY_WARM_DATA,	/* dirty segments assigned as warm data logs */
	DIRTY_COLD_DATA,	/* dirty segments assigned as cold data logs */
	DIRTY_HOT_NODE,		/* dirty segments assigned as hot node logs */
	DIRTY_WARM_NODE,	/* dirty segments assigned as warm node logs */
	DIRTY_COLD_NODE,	/* dirty segments assigned as cold node logs */
	DIRTY,			/* to count # of dirty segments */
	PRE,			/* to count # of entirely obsolete segments */
	NR_DIRTY_TYPE
};

The upper 6 bitmaps indicates segments dirtied by active log areas respectively.
And, the DIRTY bitmap integrates all the 6 bitmaps.

For example,
 o DIRTY_HOT_DATA : 1010000
 o DIRTY_WARM_DATA: 0100000
 o DIRTY_COLD_DATA: 0001000
 o DIRTY_HOT_NODE : 0000010
 o DIRTY_WARM_NODE: 0000001
 o DIRTY_COLD_NODE: 0000000
In this case,
 o DIRTY          : 1111011,

 which means that we should guarantee the consistency between DIRTY and other
 bitmaps concreately.

However, the SSR mode selects victims freely from any log types, which can set
multiple bits across the various bitmap types.

So, this patch eliminates this inconsistency.

Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-03 17:27:51 +09:00
Jaegeuk Kim
60374688a1 f2fs: allocate remained free segments in the LFS mode
This patch adds a new condition that allocates free segments in the current
active section even if SSR is needed.
Otherwise, f2fs cannot allocate remained free segments in the section since
SSR finds dirty segments only.

Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-03 17:27:50 +09:00
Jaegeuk Kim
5ec4e49f9b f2fs: change GC bitmaps to apply the section granularity
This patch removes a bitmap for victim segments selected by foreground GC, and
modifies the other bitmap for victim segments selected by background GC.

1) foreground GC bitmap
 : We don't need to manage this, since we just only one previous victim section
   number instead of the whole victim history.
   The f2fs uses the victim section number in order not to allocate currently
   GC'ed section to current active logs.

2) background GC bitmap
 : This bitmap is used to avoid selecting victims repeatedly by background GCs.
   In addition, the victims are able to be selected by foreground GCs, since
   there is no need to read victim blocks during foreground GCs.

   By the fact that the foreground GC reclaims segments in a section unit, it'd
   be better to manage this bitmap based on the section granularity.

Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-03 17:27:49 +09:00
Jaegeuk Kim
33afa7fde0 f2fs: allocate new segment aligned with sections
When allocating a new segment under the LFS mode, we should keep the section
boundary.

Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-03 17:27:49 +09:00
Jaegeuk Kim
53cf95222f f2fs: introduce TOTAL_SECS macro
Let's use a macro to get the total number of sections.

Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-03 16:23:10 +09:00
Alexandru Gheorghiu
79b5793be4 f2fs: use kmemdup
Use kmemdup instead of kzalloc and memcpy.

Signed-off-by: Alexandru Gheorghiu <gheorghiuandru@gmail.com>
Acked-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-03-31 09:12:18 +09:00
Jaegeuk Kim
437275272f f2fs: clarify and enhance the f2fs_gc flow
This patch makes clearer the ambiguous f2fs_gc flow as follows.

1. Remove intermediate checkpoint condition during f2fs_gc
 (i.e., should_do_checkpoint() and GC_BLOCKED)

2. Remove unnecessary return values of f2fs_gc because of #1.
 (i.e., GC_NODE, GC_OK, etc)

3. Simplify write_checkpoint() because of #2.

4. Clarify the main f2fs_gc flow.
 o monitor how many freed sections during one iteration of do_garbage_collect().
 o do GC more without checkpoints if we can't get enough free sections.
 o do checkpoint once we've got enough free sections through forground GCs.

5. Adopt thread-logging (Slack-Space-Recycle) scheme more aggressively on data
  log types. See. get_ssr_segement()

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-02-12 07:15:02 +09:00
Jaegeuk Kim
577e349514 f2fs: prevent checkpoint once any IO failure is detected
This patch enhances the checkpoint routine to cope with IO errors.

Basically f2fs detects IO errors from end_io_write, and the errors are able to
be occurred during one of data, node, and meta page writes.

In the previous code, when an IO error is occurred during writes, f2fs sets a
flag, CP_ERROR_FLAG, in the raw ckeckpoint buffer which will be written to disk.
Afterwards, write_checkpoint() will check the flag and remount f2fs as a
read-only (ro) mode.

However, even once f2fs is remounted as a ro mode, dirty checkpoint pages are
freely able to be written to disk by flusher or kswapd in background.
In such a case, after cold reboot, f2fs would restore the checkpoint data having
CP_ERROR_FLAG, resulting in disabling write_checkpoint and remounting f2fs as
a ro mode again.

Therefore, let's prevent any checkpoint page (meta) writes once an IO error is
occurred, and remount f2fs as a ro mode right away at that moment.

Reported-by: Oliver Winker <oliver@oli1170.net>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
2013-02-12 07:15:00 +09:00
Jaegeuk Kim
408e937561 f2fs: revisit the f2fs_gc flow
I'd like to revisit the f2fs_gc flow and rewrite as follows.

1. In practical, the nGC parameter of f2fs_gc is meaningless. So, let's
  remove it.
2. Background GC marks victim blocks as dirty one at a time.
3. Foreground GC should do cleaning job until acquiring enough free
  sections. Afterwards, it needs to do checkpoint.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-01-10 07:42:59 +09:00
Namjae Jeon
344324f10f f2fs: remove unneeded initialization of nr_dirty in dirty_seglist_info
Since, the memory for the object of dirty_seglist_info is allocated
using kzalloc - which returns zeroed out memory. So, there is no need
to initialize the nr_dirty values with zeroes.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-12-28 11:27:05 +09:00
Jaegeuk Kim
029cd28c1f f2fs: fix equation of has_not_enough_free_secs()
Practically, has_not_enough_free_secs() should calculate with the numbers of
current node and directory data blocks together.
Actually the equation was implemented in need_to_flush().

So, this patch removes need_flush() and moves the equation into
has_not_enough_free_secs().

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-12-28 11:24:10 +09:00
Jaegeuk Kim
12a67146e3 f2fs: return a default value for non-void function
This patch resolves a build warning reported by kbuild test robot.

"
fs/f2fs/segment.c: In function '__get_segment_type':
fs/f2fs/segment.c:806:1: warning: control reaches end of non-void
function [-Wreturn-type]
"

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-12-28 11:24:09 +09:00
Geert Uytterhoeven
690e4a3ead f2fs: add missing #include <linux/prefetch.h>
m68k allmodconfig:

fs/f2fs/data.c: In function ‘read_end_io’:
fs/f2fs/data.c:311: error: implicit declaration of function ‘prefetchw’

fs/f2fs/segment.c: In function ‘f2fs_end_io_write’:
fs/f2fs/segment.c:628: error: implicit declaration of function ‘prefetchw’

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-12-28 11:22:43 +09:00
Jaegeuk Kim
dfb7c0ceab f2fs: remove set_page_dirty for atomic f2fs_end_io_write
We should guarantee not to do *scheduling while atomic*.
I found, in atomic f2fs_end_io_write(), there is a set_page_dirty() call
to deal with IO errors.

But, set_page_dirty() calls:
 -> f2fs_set_data_page_dirty()
   -> set_dirty_dir_page()
      -> cond_resched() which results in scheduling.

In order to avoid this, I'd like to remove simply set_page_dirty(),
since the page is already marked as ERROR and f2fs will be operated
as the read-only mode as well.
So, there is no recovery issue with this.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-12-26 10:39:51 +09:00
Jaegeuk Kim
3cd8a23948 f2fs: cleanup the f2fs_bio_alloc routine
Do cleanup more for better code readability.

- Change the parameter set of f2fs_bio_alloc()
  This function should allocate a bio only since it is not something like
  f2fs_bio_init(). Instead, the caller should initialize the allocated bio.

- Introduce SECTOR_FROM_BLOCK
  This macro translates a block address to its sector address.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
2012-12-11 13:43:45 +09:00
Namjae Jeon
c212991a6b f2fs: rewrite f2fs_bio_alloc to make it simpler
Since, GFP_NOFS(__GFP_WAIT) is used for allocation requests of bio in f2fs.
So, there is no chance of returning NULL from the BIO allocation.

Making the bio allocation routine for f2fs simpler.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
2012-12-11 13:43:44 +09:00
Namjae Jeon
1042d60f91 f2fs: remove unneeded initialization
No need to initialize  "struct f2fs_gc_kthread *gc_th = NULL",
as gc_th = NULL, will be taken care by the return values of kmalloc().
And fix codes in other places.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
2012-12-11 13:43:44 +09:00
Jaegeuk Kim
0a8165d7c2 f2fs: adjust kernel coding style
As pointed out by Randy Dunlap, this patch removes all usage of "/**" for comment
blocks. Instead, just use "/*".

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-12-11 13:43:42 +09:00