Serialize data/node IOs by using fifo list instead of mutex lock,
it will help to enhance concurrency of f2fs, meanwhile keeping LFS
IO semantics.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch add a new method get_ssr_cost to select
SSR segment more accurately.
Signed-off-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Currently, if we do get_node_of_data before f2fs_lock_op, there may be dead lock
as follows, where process A would be in infinite loop, and B will NOT be awaked.
Process A(cp): Process B:
f2fs_lock_all(sbi)
get_dnode_of_data <---- lock dn.node_page
flush_nodes f2fs_lock_op
So, this patch adds f2fs_trylock_op to avoid f2fs_lock_op done by IPU.
Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Split DATA/NODE type bio cache according to different temperature,
so write IOs with the same temperature can be merged in corresponding
bio cache as much as possible, otherwise, different temperature write
IOs submitting into one bio cache will always cause split of bio.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Merged IO flow doesn't need to care about read IOs.
f2fs_submit_merged_bio -> f2fs_submit_merged_write
f2fs_submit_merged_bios -> f2fs_submit_merged_writes
f2fs_submit_merged_bio_cond -> f2fs_submit_merged_write_cond
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
By default, f2fs_gc returns -EINVAL in general error cases, e.g., no victim
was selected. However, the default errno may be overwritten in two cases:
gc_more and BG_GC -> FG_GC. We should return consistent errno in such cases.
Signed-off-by: Weichao Guo <guoweichao@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
We don't need to rewrite the page under cp_rwsem and dnode locks.
Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If a page is cold, NOT atomit written and need_ipu now, there is
a high probability that IPU should be adapted. For IPU, we try to
check extent tree to get the block index first, instead of reading
the dnode page, where may lead to an useless dnode IO, since no need to
update the dnode index for IPU.
Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch adds an ioctl to flush data in faster device to cold area. User can
give device number and number of segments to move. It doesn't move it if there
is only one device.
The parameter looks like:
struct f2fs_flush_device {
u32 dev_num; /* device number to flush */
u32 segments; /* # of segments to flush */
};
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Now we're doing SSR aggressively more than ever before, so once we reach to
the reserved_segment, f2fs_balance_fs will call f2fs_gc, which triggers
checkpoint everytime. We actually must avoid that.
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
- has_not_enough_free_secs
node_secs: 0 dent_secs: 0 freed:0 free_segments:103 reserved:104
- f2fs_gc
- get_victim_by_default
alloc_mode 0, gc_mode 1, max_search 2672, offset 4654, ofs_unit 1
- do_garbage_collect
start_segno 3976, end_segno 3977 type 0
- is_alive
nid 22797, blkaddr 2131882, ofs_in_node 0, version 0x8/0x0
- gc_data_segment 766, segno 3976, block 512/426 not alive
So, this patch fixes subtle corrupted case where node version does not match
to summary version which results in infinite loop by gc.
Reported-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In order to give more spatial locality, this patch changes the block allocation
policy which assigns beginning of partition for small and hot data/node blocks.
In order to do this, we set noheap allocation by default and introduce another
mount option, heap, to reset it back.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch fixes missing increased max cost caused by a patch that we increased
cose of data segments in greedy algorithm.
Cc: <stable@vger.kernel.org> # v4.10+
Fixes: b9cd20619 "f2fs: node segment is prior to data segment selected victim"
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
When doing garbage collection, we try to record segment offset which
locates at next one of last victim, using it as the start offset in
next searching.
But in some corner cases, recorded offset may cross the end of main
segment area, it will cause incorrectly searching in dirty_segmap
bitmap. This patch adds modular operation to avoid this issue.
Reported-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
fix such pclint warning:
...
Loss of precision (arg. no. 2) (unsigned long long to unsigned int))
Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
We use has_not_enough_free_secs to check if there are enough free segments,
(free_sections(sbi) + freed) <=
(node_secs + 2 * dent_secs + imeta_secs +
reserved_sections(sbi) + needed);
Under scenario with large number of dirty nodes, these nodes would be flushed
during cp, as a result, right side of the inequality would be decreased, while
left side stays unchanged if these nodes are flushed in SSR way, which means
there are enough free segments after this cp.
For this case, we just do a bggc instead of fggc.
Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Previously kernel message can show that in which function we do the
injection, but unfortunately, most of the caller are the same, for
tracking more information of injection path, it needs to show upper
caller's name. This patch supports that ability.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Since has_not_enough_free_secs(sbi, 0, 0) must be true if has_not_enough_
free_secs(sbi, sec_freed, 0) is true, write_checkpoint is sure to execute in
both conditions.
Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
As data segment gc may lead dnode dirty, so the greedy cost for data segment
should be valid blocks * 2, that is data segment is prior to node segment.
Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
For foreground gc, greedy algorithm should be adapted, which makes
this formula work well:
(2 * (100 / config.overprovision + 1) + 6)
But currently, we fg_gc have a prior to select bg_gc victim segments to gc
first, these victims are selected by cost-benefit algorithm, we can't guarantee
such segments have the small valid blocks, which may destroy the f2fs rule, on
the worstest case, would consume all the free segments.
This patch fix this by add a filter in check_bg_victims, if segment's has # of
valid blocks over overprovision ratio, skip such segments.
Cc: <stable@vger.kernel.org>
Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch introduces a new flag to indicate inode status of doing atomic
write committing, so that, we can keep atomic write status for inode
during atomic committing, then we can skip GCing pages of atomic write inode,
that avoids random GCed datas being mixed with current transaction, so
isolation of transaction can be kept.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch series contains several performance tuning patches regarding to the
IO submission flow, in addition to supporting new features such as a ZBC-base
drive and multiple devices.
It also includes some major bug fixes such as:
- checkpoint version control
- fdatasync-related roll-forward recovery routine
- memory boundary or null-pointer access in corner cases
- missing error cases
It has various minor clean-up patches as well.
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Merge tag 'for-f2fs-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"This patch series contains several performance tuning patches
regarding to the IO submission flow, in addition to supporting new
features such as a ZBC-base drive and multiple devices.
It also includes some major bug fixes such as:
- checkpoint version control
- fdatasync-related roll-forward recovery routine
- memory boundary or null-pointer access in corner cases
- missing error cases
It has various minor clean-up patches as well"
* tag 'for-f2fs-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (66 commits)
f2fs: fix a missing size change in f2fs_setattr
f2fs: fix to access nullified flush_cmd_control pointer
f2fs: free meta pages if sanity check for ckpt is failed
f2fs: detect wrong layout
f2fs: call sync_fs when f2fs is idle
Revert "f2fs: use percpu_counter for # of dirty pages in inode"
f2fs: return AOP_WRITEPAGE_ACTIVATE for writepage
f2fs: do not activate auto_recovery for fallocated i_size
f2fs: fix to determine start_cp_addr by sbi->cur_cp_pack
f2fs: fix 32-bit build
f2fs: set ->owner for debugfs status file's file_operations
f2fs: fix incorrect free inode count in ->statfs
f2fs: drop duplicate header timer.h
f2fs: fix wrong AUTO_RECOVER condition
f2fs: do not recover i_size if it's valid
f2fs: fix fdatasync
f2fs: fix to account total free nid correctly
f2fs: fix an infinite loop when flush nodes in cp
f2fs: don't wait writeback for datas during checkpoint
f2fs: fix wrong written_valid_blocks counting
...
Pull block layer updates from Jens Axboe:
"This is the main block pull request this series. Contrary to previous
release, I've kept the core and driver changes in the same branch. We
always ended up having dependencies between the two for obvious
reasons, so makes more sense to keep them together. That said, I'll
probably try and keep more topical branches going forward, especially
for cycles that end up being as busy as this one.
The major parts of this pull request is:
- Improved support for O_DIRECT on block devices, with a small
private implementation instead of using the pig that is
fs/direct-io.c. From Christoph.
- Request completion tracking in a scalable fashion. This is utilized
by two components in this pull, the new hybrid polling and the
writeback queue throttling code.
- Improved support for polling with O_DIRECT, adding a hybrid mode
that combines pure polling with an initial sleep. From me.
- Support for automatic throttling of writeback queues on the block
side. This uses feedback from the device completion latencies to
scale the queue on the block side up or down. From me.
- Support from SMR drives in the block layer and for SD. From Hannes
and Shaun.
- Multi-connection support for nbd. From Josef.
- Cleanup of request and bio flags, so we have a clear split between
which are bio (or rq) private, and which ones are shared. From
Christoph.
- A set of patches from Bart, that improve how we handle queue
stopping and starting in blk-mq.
- Support for WRITE_ZEROES from Chaitanya.
- Lightnvm updates from Javier/Matias.
- Supoort for FC for the nvme-over-fabrics code. From James Smart.
- A bunch of fixes from a whole slew of people, too many to name
here"
* 'for-4.10/block' of git://git.kernel.dk/linux-block: (182 commits)
blk-stat: fix a few cases of missing batch flushing
blk-flush: run the queue when inserting blk-mq flush
elevator: make the rqhash helpers exported
blk-mq: abstract out blk_mq_dispatch_rq_list() helper
blk-mq: add blk_mq_start_stopped_hw_queue()
block: improve handling of the magic discard payload
blk-wbt: don't throttle discard or write zeroes
nbd: use dev_err_ratelimited in io path
nbd: reset the setup task for NBD_CLEAR_SOCK
nvme-fabrics: Add FC LLDD loopback driver to test FC-NVME
nvme-fabrics: Add target support for FC transport
nvme-fabrics: Add host support for FC transport
nvme-fabrics: Add FC transport LLDD api definitions
nvme-fabrics: Add FC transport FC-NVME definitions
nvme-fabrics: Add FC transport error codes to nvme.h
Add type 0x28 NVME type code to scsi fc headers
nvme-fabrics: patch target code in prep for FC transport support
nvme-fabrics: set sqe.command_id in core not transports
parser: add u64 number parser
nvme-rdma: align to generic ib_event logging helper
...
Normally, while committing checkpoint, we will wait on all pages to be
writebacked no matter the page is data or metadata, so in scenario where
there are lots of data IO being submitted with metadata, we may suffer
long latency for waiting writeback during checkpoint.
Indeed, we only care about persistence for pages with metadata, but not
pages with data, as file system consistent are only related to metadate,
so in order to avoid encountering long latency in above scenario, let's
recognize and reference metadata in submitted IOs, wait writeback only
for metadatas.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If many threads hit has_not_enough_free_secs() in f2fs_balance_fs() at the same
time, all the threads would do FG_GC or BG_GC.
In this critical path, we totally don't need to do BG_GC at all.
Let's avoid that.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If one block has been to written to a new place, just return
in move data process. This patch check it again with holding
page lock.
Signed-off-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If there is no dirty pages in inode, we should give a chance to detach
the inode from global dirty list, otherwise it needs to call another
unnecessary .writepages for detaching.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Remove the WRITE_* and READ_SYNC wrappers, and just use the flags
directly. Where applicable this also drops usage of the
bio_set_op_attrs wrapper.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
This patch adds to support checkpoint error injection in f2fs for testing
fatal error tolerance, it will be useful that it can simulate abnormal
power off by f2fs itself instead of calling godown ioctl by running apps.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Previously, we only support global fault injection configuration, so that
when we configure type/rate of fault injection through sysfs, mount
option, it will influence all f2fs partition which is being used.
It is not make sence, since it will be not convenient if developer want
to test separated partitions with different fault injection rate/type
simultaneously, also it's not possible to enable fault injection in one
partition and disable fault injection in other one.
>From now on, we move global configuration of fault injection in module
into per-superblock, hence injection testing can be more flexible.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Otherwise, we can hit
f2fs_bug_on(sbi, !PageUptodate(sum_page));
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
We should call put_page for preloaded summary pages in do_garbage_collect.
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch adds a return value of write_checkpoint for f2fs_gc.
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch changes to check valid block number of one GCed section
directly instead of checking the number in all segments of section
one by one in order to clean up codes of foreground GC.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
replacing redundant inode page updates with mark_inode_dirty calls. And we tried
to reduce lock contentions as well to improve filesystem scalability.
Other feature is setting F2FS automatically when detecting host-managed SMR.
= Enhancement =
- ioctl to move a range of data between files
- inject orphan inode errors
- avoid flush commands congestion
- support lazytime
= Bug fixes =
- return proper results for some dentry operations
- fix deadlock in add_link failure
- disable extent_cache for fcollapse/finsert
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Merge tag 'for-f2fs-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"The major change in this version is mitigating cpu overheads on write
paths by replacing redundant inode page updates with mark_inode_dirty
calls. And we tried to reduce lock contentions as well to improve
filesystem scalability. Other feature is setting F2FS automatically
when detecting host-managed SMR.
Enhancements:
- ioctl to move a range of data between files
- inject orphan inode errors
- avoid flush commands congestion
- support lazytime
Bug fixes:
- return proper results for some dentry operations
- fix deadlock in add_link failure
- disable extent_cache for fcollapse/finsert"
* tag 'for-f2fs-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (68 commits)
f2fs: clean up coding style and redundancy
f2fs: get victim segment again after new cp
f2fs: handle error case with f2fs_bug_on
f2fs: avoid data race when deciding checkpoin in f2fs_sync_file
f2fs: support an ioctl to move a range of data blocks
f2fs: fix to report error number of f2fs_find_entry
f2fs: avoid memory allocation failure due to a long length
f2fs: reset default idle interval value
f2fs: use blk_plug in all the possible paths
f2fs: fix to avoid data update racing between GC and DIO
f2fs: add maximum prefree segments
f2fs: disable extent_cache for fcollapse/finsert inodes
f2fs: refactor __exchange_data_block for speed up
f2fs: fix ERR_PTR returned by bio
f2fs: avoid mark_inode_dirty
f2fs: move i_size_write in f2fs_write_end
f2fs: fix to avoid redundant discard during fstrim
f2fs: avoid mismatching block range for discard
f2fs: fix incorrect f_bfree calculation in ->statfs
f2fs: use percpu_rw_semaphore
...
Previous selected segment may become free after write_checkpoint,
if we do garbage collect on this segment, and then new_curseg happen
to reuse it, it may cause f2fs_bug_on as below.
panic+0x154/0x29c
do_garbage_collect+0x15c/0xaf4
f2fs_gc+0x2dc/0x444
f2fs_balance_fs.part.22+0xcc/0x14c
f2fs_balance_fs+0x28/0x34
f2fs_map_blocks+0x5ec/0x790
f2fs_preallocate_blocks+0xe0/0x100
f2fs_file_write_iter+0x64/0x11c
new_sync_write+0xac/0x11c
vfs_write+0x144/0x1e4
SyS_write+0x60/0xc0
Here, maybe we check sit and ssa type during reset_curseg. So, we check
segment is stale or not, and select a new victim to avoid this.
Signed-off-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
These two are confusing leftover of the old world order, combining
values of the REQ_OP_ and REQ_ namespaces. For callers that don't
special case we mostly just replace bi_rw with bio_data_dir or
op_is_write, except for the few cases where a switch over the REQ_OP_
values makes more sense. Any check for READA is replaced with an
explicit check for REQ_RAHEAD. Also remove the READA alias for
REQ_RAHEAD.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This patch reverts 19a5f5e2ef (f2fs: drop any block plugging),
and adds blk_plug in write paths additionally.
The main reason is that blk_start_plug can be used to wake up from low-power
mode before submitting further bios.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Datas in file can be operated by GC and DIO simultaneously, so we will
face race case as below:
For write case:
Thread A Thread B
- generic_file_direct_write
- invalidate_inode_pages2_range
- f2fs_direct_IO
- do_blockdev_direct_IO
- do_direct_IO
- get_more_blocks
- f2fs_gc
- do_garbage_collect
- gc_data_segment
- move_data_page
- do_write_data_page
migrate data block to new block address
- dio_bio_submit
update user data to old block address
For read case:
Thread A Thread B
- generic_file_direct_write
- invalidate_inode_pages2_range
- f2fs_direct_IO
- do_blockdev_direct_IO
- do_direct_IO
- get_more_blocks
- f2fs_balance_fs
- f2fs_gc
- do_garbage_collect
- gc_data_segment
- move_data_page
- do_write_data_page
migrate data block to new block address
- write_checkpoint
- do_checkpoint
- clear_prefree_segments
- f2fs_issue_discard
discard old block adress
- dio_bio_submit
update user buffer from obsolete block address
In order to fix this, for one file, we should let DIO and GC getting exclusion
against with each other.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If we fail to move data page during foreground GC, we should give another
chance to writeback that page which was set dirty previously by writer.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In procedure of synchonized read, after sending out the read request, reader
will try to lock the page for waiting device to finish the read jobs and
unlock the page, but meanwhile, truncater will race with reader, so after
reader get lock of the page, it should check page's mapping to detect
whether someone has truncated the page in advance, then reader has the
chance to do the retry if truncation was done, otherwise read can be failed
due to previous condition check.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Chao Yu