This reports performance regression by Yuanhan Liu.
The basic idea was to reduce one-point mutex, but it turns out this causes
another contention like context swithes.
https://lkml.org/lkml/2015/4/21/11
Until finishing the analysis on this issue, I'd like to revert this for a while.
This reverts commit 78373b7319.
Pull f2fs updates from Jaegeuk Kim:
"New features:
- in-memory extent_cache
- fs_shutdown to test power-off-recovery
- use inline_data to store symlink path
- show f2fs as a non-misc filesystem
Major fixes:
- avoid CPU stalls on sync_dirty_dir_inodes
- fix some power-off-recovery procedure
- fix handling of broken symlink correctly
- fix missing dot and dotdot made by sudden power cuts
- handle wrong data index during roll-forward recovery
- preallocate data blocks for direct_io
... and a bunch of minor bug fixes and cleanups"
* tag 'for-f2fs-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (71 commits)
f2fs: pass checkpoint reason on roll-forward recovery
f2fs: avoid abnormal behavior on broken symlink
f2fs: flush symlink path to avoid broken symlink after POR
f2fs: change 0 to false for bool type
f2fs: do not recover wrong data index
f2fs: do not increase link count during recovery
f2fs: assign parent's i_mode for empty dir
f2fs: add F2FS_INLINE_DOTS to recover missing dot dentries
f2fs: fix mismatching lock and unlock pages for roll-forward recovery
f2fs: fix sparse warnings
f2fs: limit b_size of mapped bh in f2fs_map_bh
f2fs: persist system.advise into on-disk inode
f2fs: avoid NULL pointer dereference in f2fs_xattr_advise_get
f2fs: preallocate fallocated blocks for direct IO
f2fs: enable inline data by default
f2fs: preserve extent info for extent cache
f2fs: initialize extent tree with on-disk extent info of inode
f2fs: introduce __{find,grab}_extent_tree
f2fs: split set_data_blkaddr from f2fs_update_extent_cache
f2fs: enable fast symlink by utilizing inline data
...
The rw parameter to direct_IO is redundant with iov_iter->type, and
treated slightly differently just about everywhere it's used: some users
do rw & WRITE, and others do rw == WRITE where they should be doing a
bitwise check. Simplify this with the new iov_iter_rw() helper, which
always returns either READ or WRITE.
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Most filesystems call through to these at some point, so we'll start
here.
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Map bh over max size which caller defined is not needed, limit it in
f2fs_map_bh.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Normally, due to DIO_SKIP_HOLES flag is set by default, blockdev_direct_IO in
f2fs_direct_IO tries to skip DIO in holes when writing inside i_size, this
makes us falling back to buffered IO which shows lower performance.
So in commit 59b802e5a4 ("f2fs: allocate data blocks in advance for
f2fs_direct_IO"), we improve perfromance by allocating data blocks in advance
if we meet holes no matter in i_size or not, since with it we can avoid falling
back to buffered IO.
But we forget to consider for unwritten fallocated block in this commit.
This patch tries to fix it for fallocate case, this helps to improve
performance.
Test result:
Storage info: sandisk ultra 64G micro sd card.
touch /mnt/f2fs/file
truncate -s 67108864 /mnt/f2fs/file
fallocate -o 0 -l 67108864 /mnt/f2fs/file
time dd if=/dev/zero of=/mnt/f2fs/file bs=1M count=64 conv=notrunc oflag=direct
Time before applying the patch:
67108864 bytes (67 MB) copied, 36.16 s, 1.9 MB/s
real 0m36.162s
user 0m0.000s
sys 0m0.180s
Time after applying the patch:
67108864 bytes (67 MB) copied, 27.7776 s, 2.4 MB/s
real 0m27.780s
user 0m0.000s
sys 0m0.036s
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch tries to preserve last extent info in extent tree cache into on-disk
inode, so this can help us to reuse the last extent info next time for
performance.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
With normal extent info cache, we records largest extent mapping between logical
block and physical block into extent info, and we persist extent info in on-disk
inode.
When we enable extent tree cache, if extent info of on-disk inode is exist, and
the extent is not a small fragmented mapping extent. We'd better to load the
extent info into extent tree cache when inode is loaded. By this way we can have
more chance to hit extent tree cache rather than taking more time to read dnode
page for block address.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch introduces __{find,grab}_extent_tree for reusing by following
patches.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Split __set_data_blkaddr from f2fs_update_extent_cache for readability.
Additionally rename __set_data_blkaddr to set_data_blkaddr for exporting.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch is to avoid some punch_hole overhead when releasing volatile data.
If volatile data was not written yet, we just can make the first page as zero.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Previously, f2fs_write_data_pages has a mutex, sbi->writepages, to serialize
data writes to maximize write bandwidth, while sacrificing multi-threads
performance.
Practically, however, multi-threads environment is much more important for
users. So this patch tries to remove the mutex.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch modifies to call set_buffer_new, if new blocks are allocated.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In __allocate_data_blocks, we should check current blkaddr which is located at
ofs_in_node of dnode page instead of checking first blkaddr all the time.
Otherwise we can only allocate one blkaddr in each dnode page. Fix it.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If a page is cached but its block was deallocated, we don't need to make
the page dirty again by gc and truncate_partial_data_page.
In that case, it needs to check its block allocation all the time instead
of giving up-to-date page.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If page's on-disk block was deallocated, let's remove up-to-date flag to avoid
further access with wrong contents.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
struct kiocb now is a generic I/O container, so move it to fs.h.
Also do a #include diet for aio.h while we're at it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
We update extent cache for all user inode of f2fs including dir inode, so this
patch gives another chance to try to get physical address of page from extent
cache for dir inode.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch switch to check FI_NO_EXTENT in f2fs_{lookup,update}_extent_cache
instead of f2fs_{lookup,update}_extent_tree or {lookup,update}_extent_info.
No functionality modification in this patch.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch adds a fast lookup path for rb-tree extent cache.
In this patch we add a recently accessed extent node pointer 'cached_en' in
extent tree. In lookup path of extent cache, we will firstly lookup the last
accessed extent node which cached_en points, if we do not hit in this node,
we will try to lookup extent node in rb-tree.
By this way we can avoid unnecessary slow lookup in rb-tree sometimes.
Note that, side-effect of this patch is that we will increase memory cost,
because we will store a pointer variable in each struct extent tree
additionally.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch adds trace for lookup/update/shrink/destroy ops in rb-tree extent cache.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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>
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>
In this patch, we do these jobs:
1. rename {check,update}_extent_cache to {lookup,update}_extent_info;
2. introduce universal lookup/update interface of extent cache:
f2fs_{lookup,update}_extent_cache including above two real functions, then
export them to function callers.
So after above cleanup, we can add new rb-tree based extent cache into exported
interfaces.
v2:
o remove "f2fs_" for inner function {lookup,update}_extent_info suggested by
Jaegeuk Kim.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch introduces f2fs_map_bh to clean codes of check_extent_cache.
v2:
o cleanup f2fs_map_bh pointed out by Jaegeuk Kim.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Rename a filed name from 'blk_addr' to 'blk' in struct {f2fs_extent,extent_info}
as annotation of this field descripts its meaning well to us.
By this way, we can avoid long statement in code of following patches.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Move ext_lock out of struct extent_info, then in the following patches we can
use variables with struct extent_info type as a parameter to pass pure data.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch fixes wrong handling of buffer_new flag in get_block.
If f2fs allocates new blocks and mapped buffer_head, it needs to set buffer_new
for the bh_result.
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>
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>
Cleanup parameters for trace_f2fs_submit_{read_,write_,page_,page_m}bio with fio
as one parameter.
Suggested-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch adds missing parameter _type_ for trace_f2fs_submit_page_bio, then
use DECLARE_EVENT_CLASS/DEFINE_EVENT_CONDITION pair to cleanup some trace event
code related to f2fs_submit_page_{m,}bio.
Additionally, after we remove redundant code, size of code can be reduced:
text data bss dec hex filename
176787 8712 56 185555 2d4d3 f2fs.ko.org
174408 8648 56 183112 2cb48 f2fs.ko
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
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>
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>
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>
Fix the wrong error number in error path of f2fs_write_begin.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
A deadlock can be occurred:
Thread 1] Thread 2]
- f2fs_write_data_pages - f2fs_write_begin
- lock_page(page #0)
- grab_cache_page(page #X)
- get_node_page(inode_page)
- grab_cache_page(page #0)
: to convert inline_data
- f2fs_write_data_page
- f2fs_write_inline_data
- get_node_page(inode_page)
In this case, trying to lock inode_page and page #0 causes deadlock.
In order to avoid this, this patch adds a rule for this locking policy,
which is that page #0 should be locked followed by inode_page lock.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
__submit_merged_bio f2fs_write_end_io f2fs_write_end_io
wait_io = X wait_io = x
complete(X) complete(X)
wait_io = NULL
wait_for_completion()
free(X)
spin_lock(X)
kernel panic
In order to avoid this, this patch removes the wait_io facility.
Instead, we can use wait_on_all_pages_writeback(sbi) to wait for end_ios.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
