We track the node sizes per-root, but they never vary from the values
in the superblock. This patch messes with the 80-column style a bit,
but subsequent patches to factor out root->fs_info into a convenience
variable fix it up again.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The io_ctl->root member was only being used to access root->fs_info.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The root is never used. We substitute extent_root in for the
reada_find_extent call, since it's only ever used to obtain the node
size. This call site will be changed to use fs_info in a later patch.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The root member is never used except for obtaining an fs_info pointer.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Even though a separate root is passed in, we're still operating on the
extent root. Let's use that for the trace point.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_init_new_device only uses the root passed in via the ioctl to
start the transaction. Nothing else that happens is related to whatever
root the user used to initiate the ioctl. We can drop the root requirement
and just use fs_info->dev_root instead.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There are many functions that are always called with the same root
argument. Rather than passing the same root every time, we can
pass an fs_info pointer instead and have the function get the root
pointer itself.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There are 11 functions that accept a root parameter and immediately
overwrite it. We can pass those an fs_info pointer instead.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This issue was found when I tried to delete a heavily reflinked file,
when deleting such files, other transaction operation will not have a
chance to make progress, for example, start_transaction() will blocked
in wait_current_trans(root) for long time, sometimes it even triggers
soft lockups, and the time taken to delete such heavily reflinked file
is also very large, often hundreds of seconds. Using perf top, it reports
that:
PerfTop: 7416 irqs/sec kernel:99.8% exact: 0.0% [4000Hz cpu-clock], (all, 4 CPUs)
---------------------------------------------------------------------------------------
84.37% [btrfs] [k] __btrfs_run_delayed_refs.constprop.80
11.02% [kernel] [k] delay_tsc
0.79% [kernel] [k] _raw_spin_unlock_irq
0.78% [kernel] [k] _raw_spin_unlock_irqrestore
0.45% [kernel] [k] do_raw_spin_lock
0.18% [kernel] [k] __slab_alloc
It seems __btrfs_run_delayed_refs() took most cpu time, after some debug
work, I found it's select_delayed_ref() causing this issue, for a delayed
head, in our case, it'll be full of BTRFS_DROP_DELAYED_REF nodes, but
select_delayed_ref() will firstly try to iterate node list to find
BTRFS_ADD_DELAYED_REF nodes, obviously it's a disaster in this case, and
waste much time.
To fix this issue, we introduce a new ref_add_list in struct btrfs_delayed_ref_head,
then in select_delayed_ref(), if this list is not empty, we can directly use
nodes in this list. With this patch, it just took about 10~15 seconds to
delte the same file. Now using perf top, it reports that:
PerfTop: 2734 irqs/sec kernel:99.5% exact: 0.0% [4000Hz cpu-clock], (all, 4 CPUs)
----------------------------------------------------------------------------------------
20.74% [kernel] [k] _raw_spin_unlock_irqrestore
16.33% [kernel] [k] __slab_alloc
5.41% [kernel] [k] lock_acquired
4.42% [kernel] [k] lock_acquire
4.05% [kernel] [k] lock_release
3.37% [kernel] [k] _raw_spin_unlock_irq
For normal files, this patch also gives help, at least we do not need to
iterate whole list to found BTRFS_ADD_DELAYED_REF nodes.
Signed-off-by: Wang Xiaoguang <wangxg.fnst@cn.fujitsu.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Commit 62b99540a1 (btrfs: relocation: Fix leaking qgroups numbers
on data extents) only fixes the problem partly.
The previous fix is to trace all new data extents at transaction commit
time when balance finishes.
However balance is not done in a large transaction, every path
replacement can happen in its own transaction.
This makes the fix useless if transaction commits during relocation.
For example:
relocate_block_group()
|-merge_reloc_roots()
| |- merge_reloc_root()
| |- btrfs_start_transaction() <- Trans X
| |- replace_path() <- Cause leak
| |- btrfs_end_transaction_throttle() <- Trans X commits here
| | Leak not fixed
| |
| |- btrfs_start_transaction() <- Trans Y
| |- replace_path() <- Cause leak
| |- btrfs_end_transaction_throttle() <- Trans Y ends
| but not committed
|-btrfs_join_transaction() <- Still trans Y
|-qgroup_fix() <- Only fixes data leak
| in trans Y
|-btrfs_commit_transaction() <- Trans Y commits
In that case, qgroup fixup can only fix data leak in trans Y, data leak
in trans X is out of fix.
So the correct fix should happen in the same transaction of
replace_path().
This patch fixes it by tracing both subtrees of tree block swap, so it
can fix the problem and ensure all leaking and fix are in the same
transaction, so no leak again.
Reported-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-and-Tested-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Move account_shared_subtree() to qgroup.c and rename it to
btrfs_qgroup_trace_subtree().
Do the same thing for account_leaf_items() and rename it to
btrfs_qgroup_trace_leaf_items().
Since all these functions are only for qgroup, move them to qgroup.c and
export them is more appropriate.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-and-Tested-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Rename btrfs_qgroup_insert_dirty_extent(_nolock) to
btrfs_qgroup_trace_extent(_nolock), according to the new
reserve/trace/account naming schema.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-and-Tested-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add explaination how btrfs qgroups work.
Qgroup is split into 3 main phrases:
1) Reserve
To ensure qgroup doesn't exceed its limit
2) Trace
To info qgroup to trace which extent
3) Account
Calculate qgroup number change for each traced extent.
This should save quite some time for new developers.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
And remove the bogus check for a NULL return value from kmap, which
can't happen. While we're at it: I don't think that kmapping up to 256
will work without deadlocks on highmem machines, a better idea would
be to use vm_map_ram to map all of them into a single virtual address
range. Incidentally that would also simplify the code a lot.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Rework the loop a little bit to use the generic bio_for_each_segment_all
helper for iterating over the bio.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Use the bvec offset and len members to prepare for multipage bvecs.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
Instead of using bi_vcnt to calculate it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Use bio_for_each_segment_all to iterate over the segments instead.
This requires a bit of reshuffling so that we only lookup up the ordered
item once inside the bio_for_each_segment_all loop.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Just use bio_for_each_segment_all to iterate over all segments.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Just use bio_for_each_segment_all to iterate over all segments.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pass the full bio to the decompression routines and use bio iterators
to iterate over the data in the bio.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
This fixes the WARN_ON on BTRFS_I(inode)->reserved_extents in
btrfs_destroy_inode and the WARN_ON on nonzero delalloc bytes on umount
with qgroups enabled.
I was able to reproduce this by setting up a small (~500kb) quota limit
and writing a file one byte at a time until I hit the limit. The warnings
would all hit on umount.
The root cause is that we would reserve a block-sized range in both
the reservation and the quota in btrfs_check_data_free_space, but if we
encountered a problem (like e.g. EDQUOT), we would only release the single
byte in the qgroup reservation. That caused an iotree state split, which
increased the number of outstanding extents, in turn disallowing releasing
the metadata reservation.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
At this point we will have dropped extent entries from the file, so if we fail
to insert the new hole entries then we are leaving the fs in a corrupt state
(albeit an easily fixed one). Abort the transaciton if this happens so we can
avoid corrupting the fs. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>