This patch adds core functions including slab cache init function and
init/lookup/update/shrink/destroy function for rb-tree based extent cache.
Thank Jaegeuk Kim and Changman Lee as they gave much suggestion about detail
design and implementation of extent cache.
Todo:
* register rb-based extent cache shrink with mm shrink interface.
v2:
o move set_extent_info and __is_{extent,back,front}_mergeable into f2fs.h.
o introduce __{attach,detach}_extent_node for code readability.
o add cond_resched() when fail to invoke kmem_cache_alloc/radix_tree_insert.
o fix some coding style and typo issues.
v3:
o fix oops due to using an unassigned pointer.
o use list_del to remove extent node in shrink list.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
[Jaegeuk Kim: add static for some funcitons and declare in f2fs.h]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch fixes the following test.
This causes:
attempt to access beyond end of device
sdb2: rw=16384, want=14413962000, limit=16777216
The reason is:
- f2fs_write_begin
- f2fs_convert_inline_inode returns -ENOSPC
- f2fs_write_failed
- truncate_blocks
- truncate_partial_data_page
- find_data_page
- get_dnode_of_data returns wrong data index retrieved from inline_data
- f2fs_submit_page_bio(wrong data index)
- submit_bio(wrong data index)
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In get_node_page, if the page is up-to-date, we assumed that the page was not
reclaimed at all.
But, sometimes it was reported that its contents was missing.
So, just for sure, let's check its mapping and contents.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch merges ->{invalidate,release}page function for meta/node/data pages.
After this, duplication of codes could be removed.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Currently, there are several variables with Boolean type as below:
struct f2fs_sb_info {
...
int s_dirty;
bool need_fsck;
bool s_closing;
...
bool por_doing;
...
}
For this there are some issues:
1. there are some space of f2fs_sb_info is wasted due to aligning after Boolean
type variables by compiler.
2. if we continuously add new flag into f2fs_sb_info, structure will be messed
up.
So in this patch, we try to:
1. switch s_dirty to Boolean type variable since it has two status 0/1.
2. merge s_dirty/need_fsck/s_closing/por_doing variables into s_flag.
3. introduce an enum type which can indicate different states of sbi.
4. use new introduced universal interfaces is_sbi_flag_set/{set,clear}_sbi_flag
to operate flags for sbi.
After that, above issues will be fixed.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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>
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>
Use more common function ra_meta_pages() with META_POR to readahead node blocks
in restore_node_summary() instead of ra_sum_pages(), hence we can simplify the
readahead code there, and also we can remove unused function ra_sum_pages().
changes from v2:
o use invalidate_mapping_pages as before suggested by Changman Lee.
changes from v1:
o fix one bug when using truncate_inode_pages_range which is pointed out by
Jaegeuk Kim.
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>
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>
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>
We don't need to force to write dirty_exceeded for f2fs_balance_fs_bg.
This flag was only meaningful to write bypassing conditions.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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>
This patch tries to fix:
BUG: using smp_processor_id() in preemptible [00000000] code: f2fs_gc-254:0/384
(radix_tree_node_alloc+0x14/0x74) from [<c033d8a0>] (radix_tree_insert+0x110/0x200)
(radix_tree_insert+0x110/0x200) from [<c02e8264>] (gc_data_segment+0x340/0x52c)
(gc_data_segment+0x340/0x52c) from [<c02e8658>] (f2fs_gc+0x208/0x400)
(f2fs_gc+0x208/0x400) from [<c02e8a98>] (gc_thread_func+0x248/0x28c)
(gc_thread_func+0x248/0x28c) from [<c0139944>] (kthread+0xa0/0xac)
(kthread+0xa0/0xac) from [<c0105ef8>] (ret_from_fork+0x14/0x3c)
The reason is that f2fs calls radix_tree_insert under enabled preemption.
So, before calling it, we need to call radix_tree_preload.
Otherwise, we should use _GFP_WAIT for the radix tree, and use mutex or
semaphore to cover the radix tree operations.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Previoulsy, we used rwlock for nat_entry lock.
But, now we have a lot of complex operations in set_node_addr.
(e.g., allocating kernel memories, handling radix_trees, and so on)
So, this patches tries to change spinlock to rw_semaphore to give CPUs to other
threads.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
After flushing dirty nat entries, it has to be no more dirty nat
entries.
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
It's meaningless to check dirty_nat_cnt after re-dirtying nat entries in
journal. And although there are rooms for dirty nat entires if dirty_nat_cnt
is zero, it's also meaningless to check __has_cursum_space.
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Two jump labels were adjusted in the implementation of the
create_node_manager_caches() function because these identifiers
contained typos.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If a node page is request to be written during the reclaiming path, we should
submit the bio to avoid pending to recliam it.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Now in f2fs, we have three inode cache: ORPHAN_INO, APPEND_INO, UPDATE_INO,
and we manage fields related to inode cache separately in struct f2fs_sb_info
for each inode cache type.
This makes codes a bit messy, so that this patch intorduce a new struct
inode_management to wrap inner fields as following which make codes more neat.
/* for inner inode cache management */
struct inode_management {
struct radix_tree_root ino_root; /* ino entry array */
spinlock_t ino_lock; /* for ino entry lock */
struct list_head ino_list; /* inode list head */
unsigned long ino_num; /* number of entries */
};
struct f2fs_sb_info {
...
struct inode_management im[MAX_INO_ENTRY]; /* manage inode cache */
...
}
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
It needs to write node pages if checkpoint is not doing in order to avoid
memory pressure.
Reviewed-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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>
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>
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>
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>
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>
This verifies to truncate any allocated blocks, offset[0], by inline_data.
Not figured out, but for making sure.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Theoretically, our total inodes number is the same as total node number, but
there are three node ids are reserved in f2fs, they are 0, 1 (node nid), and 2
(meta nid), and they should never be used by user, so our total/free inode
number calculated in ->statfs is wrong.
This patch indroduces F2FS_RESERVED_NODE_NUM and then fixes this issue by
recalculating total/free inode number with the macro.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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>
There are two rules when EIO is occurred.
1. don't write any checkpoint data to preserve the previous checkpoint
2. don't lose the cached dentry/node/meta pages
So, at first, this patch adds set_page_dirty in f2fs_write_end_io's failure.
Then, writing checkpoint/dentry/node blocks is not allowed.
Note that, for the data pages, we can't just throw away by redirtying them.
Otherwise, kworker can fall into infinite loop to flush them.
(Ref. xfstests/019)
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch fixes not to skip xattr recovery and inline xattr/data recovery
order.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
During the recovery, we should clear the inline_xattr flag if its xattr node
block is recovered.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If a new inode page is needed for recover_dentry, we should assing i_inline
as zero.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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>
When we recover data of inode in roll-forward procedure, and the inode has both
inline data and inline xattr. We may skip recovering inline xattr if we recover
inline data form node page first.
This patch will fix the problem that we lost inline xattr data in above
scenario.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
We do not need to block on ->node_write among different node page writers e.g.
fsync/flush, unless we have a node page writer from write_checkpoint.
So it's better use rw_semaphore instead of mutex type for ->node_write to
promote performance.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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>
If we don't check the current backing device status, balance_dirty_pages can
fall into infinite pausing routine.
This can be occurred when a lot of directories make a small number of dirty
dentry pages including files.
Reported-by: Brian Chadwick <brianchad@westnet.com.au>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch-set includes the following major enhancement patches.
o enhance wait_on_page_writeback
o support SEEK_DATA and SEEK_HOLE
o enhance readahead flows
o enhance IO flushes
o support fiemap
o add some tracepoints
The other bug fixes are as follows.
o fix to support a large volume > 2TB correctly
o recovery bug fix wrt fallocated space
o fix recursive lock on xattr operations
o fix some cases on the remount flow
And, there are a bunch of cleanups.
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Merge tag 'for-f2fs-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"In this round, there is no special interesting feature, but we've
investigated a couple of tuning points with respect to the I/O flow.
Several major bug fixes and a bunch of clean-ups also have been made.
This patch-set includes the following major enhancement patches:
- enhance wait_on_page_writeback
- support SEEK_DATA and SEEK_HOLE
- enhance readahead flows
- enhance IO flushes
- support fiemap
- add some tracepoints
The other bug fixes are as follows:
- fix to support a large volume > 2TB correctly
- recovery bug fix wrt fallocated space
- fix recursive lock on xattr operations
- fix some cases on the remount flow
And, there are a bunch of cleanups"
* tag 'for-f2fs-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (52 commits)
f2fs: support f2fs_fiemap
f2fs: avoid not to call remove_dirty_inode
f2fs: recover fallocated space
f2fs: fix to recover data written by dio
f2fs: large volume support
f2fs: avoid crash when trace f2fs_submit_page_mbio event in ra_sum_pages
f2fs: avoid overflow when large directory feathure is enabled
f2fs: fix recursive lock by f2fs_setxattr
MAINTAINERS: add a co-maintainer from samsung for F2FS
MAINTAINERS: change the email address for f2fs
f2fs: use inode_init_owner() to simplify codes
f2fs: avoid to use slab memory in f2fs_issue_flush for efficiency
f2fs: add a tracepoint for f2fs_read_data_page
f2fs: add a tracepoint for f2fs_write_{meta,node,data}_pages
f2fs: add a tracepoint for f2fs_write_{meta,node,data}_page
f2fs: add a tracepoint for f2fs_write_end
f2fs: add a tracepoint for f2fs_write_begin
f2fs: fix checkpatch warning
f2fs: deactivate inode page if the inode is evicted
f2fs: decrease the lock granularity during write_begin
...
aops->write_begin may allocate a new page and make it visible only to have
mark_page_accessed called almost immediately after. Once the page is
visible the atomic operations are necessary which is noticable overhead
when writing to an in-memory filesystem like tmpfs but should also be
noticable with fast storage. The objective of the patch is to initialse
the accessed information with non-atomic operations before the page is
visible.
The bulk of filesystems directly or indirectly use
grab_cache_page_write_begin or find_or_create_page for the initial
allocation of a page cache page. This patch adds an init_page_accessed()
helper which behaves like the first call to mark_page_accessed() but may
called before the page is visible and can be done non-atomically.
The primary APIs of concern in this care are the following and are used
by most filesystems.
find_get_page
find_lock_page
find_or_create_page
grab_cache_page_nowait
grab_cache_page_write_begin
All of them are very similar in detail to the patch creates a core helper
pagecache_get_page() which takes a flags parameter that affects its
behavior such as whether the page should be marked accessed or not. Then
old API is preserved but is basically a thin wrapper around this core
function.
Each of the filesystems are then updated to avoid calling
mark_page_accessed when it is known that the VM interfaces have already
done the job. There is a slight snag in that the timing of the
mark_page_accessed() has now changed so in rare cases it's possible a page
gets to the end of the LRU as PageReferenced where as previously it might
have been repromoted. This is expected to be rare but it's worth the
filesystem people thinking about it in case they see a problem with the
timing change. It is also the case that some filesystems may be marking
pages accessed that previously did not but it makes sense that filesystems
have consistent behaviour in this regard.
The test case used to evaulate this is a simple dd of a large file done
multiple times with the file deleted on each iterations. The size of the
file is 1/10th physical memory to avoid dirty page balancing. In the
async case it will be possible that the workload completes without even
hitting the disk and will have variable results but highlight the impact
of mark_page_accessed for async IO. The sync results are expected to be
more stable. The exception is tmpfs where the normal case is for the "IO"
to not hit the disk.
The test machine was single socket and UMA to avoid any scheduling or NUMA
artifacts. Throughput and wall times are presented for sync IO, only wall
times are shown for async as the granularity reported by dd and the
variability is unsuitable for comparison. As async results were variable
do to writback timings, I'm only reporting the maximum figures. The sync
results were stable enough to make the mean and stddev uninteresting.
The performance results are reported based on a run with no profiling.
Profile data is based on a separate run with oprofile running.
async dd
3.15.0-rc3 3.15.0-rc3
vanilla accessed-v2
ext3 Max elapsed 13.9900 ( 0.00%) 11.5900 ( 17.16%)
tmpfs Max elapsed 0.5100 ( 0.00%) 0.4900 ( 3.92%)
btrfs Max elapsed 12.8100 ( 0.00%) 12.7800 ( 0.23%)
ext4 Max elapsed 18.6000 ( 0.00%) 13.3400 ( 28.28%)
xfs Max elapsed 12.5600 ( 0.00%) 2.0900 ( 83.36%)
The XFS figure is a bit strange as it managed to avoid a worst case by
sheer luck but the average figures looked reasonable.
samples percentage
ext3 86107 0.9783 vmlinux-3.15.0-rc4-vanilla mark_page_accessed
ext3 23833 0.2710 vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed
ext3 5036 0.0573 vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed
ext4 64566 0.8961 vmlinux-3.15.0-rc4-vanilla mark_page_accessed
ext4 5322 0.0713 vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed
ext4 2869 0.0384 vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed
xfs 62126 1.7675 vmlinux-3.15.0-rc4-vanilla mark_page_accessed
xfs 1904 0.0554 vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed
xfs 103 0.0030 vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed
btrfs 10655 0.1338 vmlinux-3.15.0-rc4-vanilla mark_page_accessed
btrfs 2020 0.0273 vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed
btrfs 587 0.0079 vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed
tmpfs 59562 3.2628 vmlinux-3.15.0-rc4-vanilla mark_page_accessed
tmpfs 1210 0.0696 vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed
tmpfs 94 0.0054 vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed
[akpm@linux-foundation.org: don't run init_page_accessed() against an uninitialised pointer]
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Jan Kara <jack@suse.cz>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Tested-by: Prabhakar Lad <prabhakar.csengg@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If data are overwritten through dio, previous f2fs doesn't remain the fsync mark
due to no additional node writes.
Note that this patch should resolve the xfstests:311.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Previously we allocate pages with no mapping in ra_sum_pages(), so we may
encounter a crash in event trace of f2fs_submit_page_mbio where we access
mapping data of the page.
We'd better allocate pages in bd_inode mapping and invalidate these pages after
we restore data from pages. It could avoid crash in above scenario.
Changes from V1
o remove redundant code in ra_sum_pages() suggested by Jaegeuk Kim.
Call Trace:
[<f1031630>] ? ftrace_raw_event_f2fs_write_checkpoint+0x80/0x80 [f2fs]
[<f10377bb>] f2fs_submit_page_mbio+0x1cb/0x200 [f2fs]
[<f103c5da>] restore_node_summary+0x13a/0x280 [f2fs]
[<f103e22d>] build_curseg+0x2bd/0x620 [f2fs]
[<f104043b>] build_segment_manager+0x1cb/0x920 [f2fs]
[<f1032c85>] f2fs_fill_super+0x535/0x8e0 [f2fs]
[<c115b66a>] mount_bdev+0x16a/0x1a0
[<f102f63f>] f2fs_mount+0x1f/0x30 [f2fs]
[<c115c096>] mount_fs+0x36/0x170
[<c1173635>] vfs_kern_mount+0x55/0xe0
[<c1175388>] do_mount+0x1e8/0x900
[<c1175d72>] SyS_mount+0x82/0xc0
[<c16059cc>] sysenter_do_call+0x12/0x22
Suggested-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
