For normal inodes, their pages are allocated with __GFP_FS, which can cause
filesystem calls when reclaiming memory.
This can incur a dead lock condition accordingly.
So, this patch addresses this problem by introducing
f2fs_grab_cache_page(.., bool for_write), which calls
grab_cache_page_write_begin() with AOP_FLAG_NOFS.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch introduces a tracepoint to monitor background gc behaviors.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch drops in batches gc triggered through ioctl, since user
can easily control the gc by designing the loop around the ->ioctl.
We support synchronous gc by forcing using FG_GC in f2fs_gc, so with
it, user can make sure that in this round all blocks gced were
persistent in the device until ioctl returned.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
When searching victim during gc, if there are no dirty segments in
filesystem, we will still take the time to search the whole dirty segment
map, it's not needed, it's better to skip in this condition.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
When doing gc, we search a victim in dirty map, starting from position of
last victim, we will reset the current searching position until we touch
the end of dirty map, and then search the whole diryt map. So sometimes we
will search the range [victim, last] twice, it's redundant, this patch
avoids this issue.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If we do not call get_victim first, we cannot get a new victim for retrial
path.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch fixes to maintain the right section count freed in garbage
collecting when triggering a foreground gc.
Besides, when a foreground gc is running on current selected section, once
we fail to gc one segment, it's better to abandon gcing the left segments
in current section, because anyway we will select next victim for
foreground gc, so gc on the left segments in previous section will become
overhead and also cause the long latency for caller.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If FG_GC failed to reclaim one section, let's retry with another section
from the start, since we can get anoterh good candidate.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If node blocks were already moved, we don't need to move them again.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
We should avoid needless checkpoints when there is no dirty and prefree segment.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
That encrypted page is used temporarily, so we don't need to mark it accessed.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This makes the function check_dnode have a return type of bool
due to this particular function only ever returning either one
or zero as its return value and changes the name of the function
to is_alive in order to better explain this function's intended
work of checking if a dnode is still in use by the filesystem.
Signed-off-by: Nicholas Krause <xerofoify@gmail.com>
[Jaegeuk Kim: change the return value check for the renamed function]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch adds encryption support in read and write paths.
Note that, in f2fs, we need to consider cleaning operation.
In cleaning procedure, we must avoid encrypting and decrypting written blocks.
So, this patch implements move_encrypted_block().
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch splits find_data_page as follows.
1. f2fs_gc
- use get_read_data_page() with read only
2. find_in_level
- use find_data_page without locked page
3. truncate_partial_page
- In the case cache_only mode, just drop cached page.
- Ohterwise, use get_lock_data_page() and guarantee to truncate
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch adds f2fs_sb_info and page pointers in f2fs_io_info structure.
With this change, we can reduce a lot of parameters for IO functions.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch is for looking into gc performance of f2fs in detail.
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
[Jaegeuk Kim: fix build errors]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch adds FASTBOOT flag into checkpoint as follows.
- CP_UMOUNT_FLAG is set when system is umounted.
- CP_FASTBOOT_FLAG is set when intermediate checkpoint having node summaries
was done.
So, if you get CP_UMOUNT_FLAG from checkpoint, the system was umounted cleanly.
Instead, if there was sudden-power-off, you can get CP_FASTBOOT_FLAG or nothing.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Use pointer parameter @wait to pass result in {in,de}create_sleep_time for
cleanup.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
No modification in functionality, just clean codes with f2fs_radix_tree_insert.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
There are two slab cache inode_entry_slab and winode_slab using the same
structure as below:
struct dir_inode_entry {
struct list_head list; /* list head */
struct inode *inode; /* vfs inode pointer */
};
struct inode_entry {
struct list_head list;
struct inode *inode;
};
It's a little waste that the two cache can not share their memory space for each
other.
So in this patch we remove one redundant winode_slab slab cache, then use more
universal name struct inode_entry as remaining data structure name of slab,
finally we reuse the inode_entry_slab to store dirty dir item and gc item for
more effective.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
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>
If there are many inodes that have data blocks in victim segment,
it takes long time to find a inode in gc_inode list.
Let's use radix_tree to reduce lookup time.
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Little cleanup to distinguish each phase easily
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
[Jaegeuk Kim: modify indentation for code readability]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In f2fs_remount, we will stop gc thread and set need_restart_gc as true when new
option is set without BG_GC, then if any error occurred in the following
procedure, we can restore to start the gc thread.
But after that, We will fail to restore gc thread in start_gc_thread as BG_GC is
not set in new option, so we'd better move this condition judgment out of
start_gc_thread to fix this issue.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If a system wants to reduce the booting time as a top priority, now we can
use a mount option, -o fastboot.
With this option, f2fs conducts a little bit slow write_checkpoint, but
it can avoid the node page reads during the next mount time.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Remove the unneeded argument 'type' from __get_victim, use
NO_CHECK_TYPE directly when calling v_ops->get_victim().
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch add a new data structure to control checkpoint parameters.
Currently, it presents the reason of checkpoint such as is_umount and normal
sync.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In ->get_victim we get max_search value from dirty_i->nr_dirty without
protection of seglist_lock, after that, nr_dirty can be increased/decreased
before we hold seglist_lock lock.
Then in main loop we attempt to traverse all dirty section one time to find
victim section, but it's not accurate to use max_search as the total loop count,
because we might lose checking several sections or check sections redundantly
for the case of nr_dirty are increased or decreased previously.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Previously f2fs only counts dirty dentry pages, but there is no reason not to
expand the scope.
This patch changes the names on the management of dirty pages and to count
dirty pages in each inode info as well.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In gc_node_segment, if node page gc is run concurrently with node page
writeback, and check_valid_map and get_node_page run after page locked
and before cur_valid_map is updated as below, it is possible for the
page to be written twice unnecessarily.
sync_node_pages
try_lock_page
...
check_valid_map f2fs_write_node_page
...
write_node_page
do_write_page
allocate_data_block
...
refresh_sit_entry /* update cur_valid_map */
...
...
unlock_page
get_node_page
...
set_page_dirty
...
f2fs_put_page
unlock_page
This can be solved via calling check_valid_map after get_node_page again.
Signed-off-by: Huang, Ying <ying.huang@intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
As the race condition on the inode cache, following scenario can appear:
[Thread a] [Thread b]
->f2fs_mkdir
->f2fs_add_link
->__f2fs_add_link
->init_inode_metadata failed here
->gc_thread_func
->f2fs_gc
->do_garbage_collect
->gc_data_segment
->f2fs_iget
->iget_locked
->wait_on_inode
->unlock_new_inode
->move_data_page
->make_bad_inode
->iput
When we fail in create/symlink/mkdir/mknod/tmpfile, the new allocated inode
should be set as bad to avoid being accessed by other thread. But in above
scenario, it allows f2fs to access the invalid inode before this inode was set
as bad.
This patch fix the potential problem, and this issue was found by code review.
change log from v1:
o Add condition judgment in gc_data_segment() suggested by Changman Lee.
o use iget_failed to simplify code.
Signed-off-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>
This patch uses for_each_set_bit to simplify some codes in f2fs.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If there are multi segments in one section, we will read those SSA blocks which
have contiguous address one by one in f2fs_gc. It may lost performance, let's
read ahead SSA blocks by merge multi read request.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
If f2fs entered errorneous checkpoint status, it should skip writing meta
pages instead of redirtying the pages out.
Otherwise, it cannot unmount the partition even though f2fs is under read-only
status.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
"boo sync" parameter is never referenced in f2fs_wait_on_page_writeback.
We should remove this parameter.
Signed-off-by: Yuan Zhong <yuan.mark.zhong@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Previously during SSR and GC, the maximum number of retrials to find a victim
segment was hard-coded by MAX_VICTIM_SEARCH, 4096 by default.
This number makes an effect on IO locality, when SSR mode is activated, which
results in performance fluctuation on some low-end devices.
If max_victim_search = 4, the victim will be searched like below.
("D" represents a dirty segment, and "*" indicates a selected victim segment.)
D1 D2 D3 D4 D5 D6 D7 D8 D9
[ * ]
[ * ]
[ * ]
[ ....]
This patch adds a sysfs entry to control the number dynamically through:
/sys/fs/f2fs/$dev/max_victim_search
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
When using the f2fs_io_info in the low level, we still need to merge the
rw and rw_flag, so use the rw to hold all the io flags directly,
and remove the rw_flag field.
ps.It is based on the previous patch:
f2fs: move all the bio initialization into __bio_alloc
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This patch introduces f2fs_io_info to mitigate the complex parameter list.
struct f2fs_io_info {
enum page_type type; /* contains DATA/NODE/META/META_FLUSH */
int rw; /* contains R/RS/W/WS */
int rw_flag; /* contains REQ_META/REQ_PRIO */
}
1. f2fs_write_data_pages
- DATA
- WRITE_SYNC is set when wbc->WB_SYNC_ALL.
2. sync_node_pages
- NODE
- WRITE_SYNC all the time
3. sync_meta_pages
- META
- WRITE_SYNC all the time
- REQ_META | REQ_PRIO all the time
** f2fs_submit_merged_bio() handles META_FLUSH.
4. ra_nat_pages, ra_sit_pages, ra_sum_pages
- META
- READ_SYNC
Cc: Fan Li <fanofcode.li@samsung.com>
Cc: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Previously f2fs submits most of write requests using WRITE_SYNC, but f2fs_write_data_pages
submits last write requests by sync_mode flags callers pass.
This causes a performance problem since continuous pages with different sync flags
can't be merged in cfq IO scheduler(thanks yu chao for pointing it out), and synchronous
requests often take more time.
This patch makes the following modifies to DATA writebacks:
1. every page will be written back using the sync mode caller pass.
2. only pages with the same sync mode can be merged in one bio request.
These changes are restricted to DATA pages.Other types of writebacks are modified
To remain synchronous.
In my test with tiotest, f2fs sequence write performance is improved by about 7%-10% ,
and this patch has no obvious impact on other performance tests.
Signed-off-by: Fan Li <fanofcode.li@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
