Christoph Hellwig [Wed, 31 May 2023 07:53:56 +0000 (09:53 +0200)]
btrfs: merge the two calls to btrfs_add_ordered_extent in run_delalloc_nocow
Refactor run_delalloc_nocow a little bit so that there is only a single
call to btrfs_add_ordered_extent instead of two.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 31 May 2023 07:53:55 +0000 (09:53 +0200)]
btrfs: limit write bios to a single ordered extent
Currently buffered writeback bios are allowed to span multiple
ordered_extents, although that basically never actually happens since
commit
4a445b7b6178 ("btrfs: don't merge pages into bio if their page
offset is not contiguous").
Supporting bios than span ordered_extents complicates the file
checksumming code, and prevents us from adding an ordered_extent pointer
to the btrfs_bio structure. Use the existing code to limit a bio to
single ordered_extent for zoned device writes for all writes.
This allows to remove the REQ_BTRFS_ONE_ORDERED flags, and the
handling of multiple ordered_extents in btrfs_csum_one_bio.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 31 May 2023 07:53:54 +0000 (09:53 +0200)]
btrfs: fix file_offset for REQ_BTRFS_ONE_ORDERED bios that get split
If a bio gets split, it needs to have a proper file_offset for checksum
validation and repair to work properly.
Based on feedback from Josef, commit
852eee62d31a ("btrfs: allow
btrfs_submit_bio to split bios") skipped this adjustment for ONE_ORDERED
bios. But if we actually ever need to split a ONE_ORDERED read bio, this
will lead to a wrong file offset in the repair code. Right now the only
user of the file_offset is logging of an error message so this is mostly
harmless, but the wrong offset might be more problematic for additional
users in the future.
Fixes:
852eee62d31a ("btrfs: allow btrfs_submit_bio to split bios")
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Wed, 31 May 2023 22:33:01 +0000 (00:33 +0200)]
btrfs: add block-group tree to lockdep classes
The block group tree was not present among the lockdep classes. We could
get potentially lockdep warnings but so far none has been seen, also
because block-group-tree is a relatively new feature.
CC: stable@vger.kernel.org # 6.1+
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 31 May 2023 06:05:02 +0000 (08:05 +0200)]
btrfs: don't treat zoned writeback as being from an async helper thread
When extent_write_locked_range was originally added, it was only used
writing back compressed pages from an async helper thread. But it is
now also used for writing back pages on zoned devices, where it is
called directly from the ->writepage context. In this case we want to
be able to pass on the writeback_control instead of creating a new one,
and more importantly want to use all the normal cgroup interaction
instead of potentially deferring writeback to another helper.
Fixes:
898793d992c2 ("btrfs: zoned: write out partially allocated region")
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 31 May 2023 06:05:01 +0000 (08:05 +0200)]
btrfs: only call __extent_writepage_io from extent_write_locked_range
__extent_writepage does a lot of things that make no sense for
extent_write_locked_range, given that extent_write_locked_range itself is
called from __extent_writepage either directly or through a workqueue,
and all this work has already been done in the first invocation and the
pages haven't been unlocked since. Call __extent_writepage_io directly
instead and open code the logic tracked in
btrfs_bio_ctrl::extent_locked.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 31 May 2023 06:05:00 +0000 (08:05 +0200)]
btrfs: move writeback_control::nr_to_write update to __extent_writepage
Move the nr_to_write accounting from __extent_writepage_io to
__extent_writepage_io as we'll grow another __extent_writepage_io that
doesn't want this accounting soon. Also drop the obsolete comment -
decrementing a counter in the on-stack writeback_control data structure
doesn't need the page lock.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 31 May 2023 06:04:59 +0000 (08:04 +0200)]
btrfs: remove non-standard extent handling in __extent_writepage_io
__extent_writepage_io is never called for compressed or inline extents,
or holes. Remove the not quite working code for them and replace it with
asserts that these cases don't happen.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 31 May 2023 06:04:58 +0000 (08:04 +0200)]
btrfs: remove PAGE_SET_ERROR
Now that the btrfs writeback code has stopped using PageError, using
PAGE_SET_ERROR to just set the per-address_space error flag is confusing.
Open code the mapping_set_error calls in the callers and remove
the PAGE_SET_ERROR flag.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 31 May 2023 06:04:57 +0000 (08:04 +0200)]
btrfs: stop setting PageError in the data I/O path
PageError is not used by the VFS/MM and deprecated because it uses up a
page bit and has no coherent rules. Instead read errors are usually
propagated by not setting or clearing the uptodate bit, and write errors
are propagated through the address_space. Btrfs now only sets the flag
and never clears it for data pages, so just remove all places setting it,
and the subpage error bit.
Note that the error propagation for superblock writes that work on the
block device mapping still uses PageError for now, but that will be
addressed in a separate series.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 31 May 2023 06:04:56 +0000 (08:04 +0200)]
btrfs: don't check PageError in __extent_writepage
__extent_writepage currenly sets PageError whenever any error happens,
and the also checks for PageError to decide if to call error handling.
This leads to very unclear responsibility for cleaning up on errors.
In the VM and generic writeback helpers the basic idea is that once
I/O is fired off all error handling responsibility is delegated to the
end I/O handler. But if that end I/O handler sets the PageError bit,
and the submitter checks it, the bit could in some cases leak into the
submission context for fast enough I/O.
Fix this by simply not checking PageError and just using the local
ret variable to check for submission errors. This also fundamentally
solves the long problem documented in a comment in __extent_writepage
by never leaking the error bit into the submission context.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 31 May 2023 06:04:55 +0000 (08:04 +0200)]
btrfs: rename cow_file_range_async to run_delalloc_compressed
cow_file_range_async is only used for compressed writeback. Rename it
to run_delalloc_compressed, which also fits in with run_delalloc_nocow
and run_delalloc_zoned.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 31 May 2023 06:04:54 +0000 (08:04 +0200)]
btrfs: don't fail writeback when allocating the compression context fails
If cow_file_range_async fails to allocate the asynchronous writeback
context, it currently returns an error and entirely fails the writeback.
This is not a good idea as a writeback failure is a non-temporary error
condition that will make the file system unusable. Just fall back to
synchronous uncompressed writeback instead. This requires us to delay
setting the BTRFS_INODE_HAS_ASYNC_EXTENT flag until we've committed to
the async writeback.
The compression checks INODE_NOCOMPRESS and FORCE_COMPRESS are moved
from cow_file_range_async to the preceding checks btrfs_run_delalloc_range().
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 31 May 2023 06:04:53 +0000 (08:04 +0200)]
btrfs: don't check PageError in btrfs_verify_page
btrfs_verify_page is called from the readpage completion handler, which
is only used to read pages, or parts of pages that aren't uptodate yet.
The only case where PageError could be set on a page in btrfs is if we
had a previous writeback error, but in that case we won't called readpage
on it, as it has previously been marked uptodate.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 31 May 2023 06:04:52 +0000 (08:04 +0200)]
btrfs: fix fsverify read error handling in end_page_read
Also clear the uptodate bit to make sure the page isn't seen as uptodate
in the page cache if fsverity verification fails.
Fixes:
146054090b08 ("btrfs: initial fsverity support")
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 31 May 2023 06:04:51 +0000 (08:04 +0200)]
btrfs: factor out a btrfs_verify_page helper
Split all the conditionals for the fsverity calls in end_page_read into
a btrfs_verify_page helper to keep the code readable and make additional
refactoring easier.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 31 May 2023 06:04:50 +0000 (08:04 +0200)]
btrfs: fix range_end calculation in extent_write_locked_range
The range_end field in struct writeback_control is inclusive, just like
the end parameter passed to extent_write_locked_range. Not doing this
could cause extra writeout, which is harmless but suboptimal.
Fixes:
771ed689d2cd ("Btrfs: Optimize compressed writeback and reads")
CC: stable@vger.kernel.org # 5.9+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Boris Burkov [Thu, 1 Jun 2023 18:55:14 +0000 (11:55 -0700)]
btrfs: insert tree mod log move in push_node_left
There is a fairly unlikely race condition in tree mod log rewind that
can result in a kernel panic which has the following trace:
[530.569] BTRFS critical (device sda3): unable to find logical 0 length 4096
[530.585] BTRFS critical (device sda3): unable to find logical 0 length 4096
[530.602] BUG: kernel NULL pointer dereference, address:
0000000000000002
[530.618] #PF: supervisor read access in kernel mode
[530.629] #PF: error_code(0x0000) - not-present page
[530.641] PGD 0 P4D 0
[530.647] Oops: 0000 [#1] SMP
[530.654] CPU: 30 PID: 398973 Comm: below Kdump: loaded Tainted: G S O K 5.12.0-0_fbk13_clang_7455_gb24de3bdb045 #1
[530.680] Hardware name: Quanta Mono Lake-M.2 SATA 1HY9U9Z001G/Mono Lake-M.2 SATA, BIOS F20_3A15 08/16/2017
[530.703] RIP: 0010:__btrfs_map_block+0xaa/0xd00
[530.755] RSP: 0018:
ffffc9002c2f7600 EFLAGS:
00010246
[530.767] RAX:
ffffffffffffffea RBX:
ffff888292e41000 RCX:
f2702d8b8be15100
[530.784] RDX:
ffff88885fda6fb8 RSI:
ffff88885fd973c8 RDI:
ffff88885fd973c8
[530.800] RBP:
ffff888292e410d0 R08:
ffffffff82fd7fd0 R09:
00000000fffeffff
[530.816] R10:
ffffffff82e57fd0 R11:
ffffffff82e57d70 R12:
0000000000000000
[530.832] R13:
0000000000001000 R14:
0000000000001000 R15:
ffffc9002c2f76f0
[530.848] FS:
00007f38d64af000(0000) GS:
ffff88885fd80000(0000) knlGS:
0000000000000000
[530.866] CS: 0010 DS: 0000 ES: 0000 CR0:
0000000080050033
[530.880] CR2:
0000000000000002 CR3:
00000002b6770004 CR4:
00000000003706e0
[530.896] DR0:
0000000000000000 DR1:
0000000000000000 DR2:
0000000000000000
[530.912] DR3:
0000000000000000 DR6:
00000000fffe0ff0 DR7:
0000000000000400
[530.928] Call Trace:
[530.934] ? btrfs_printk+0x13b/0x18c
[530.943] ? btrfs_bio_counter_inc_blocked+0x3d/0x130
[530.955] btrfs_map_bio+0x75/0x330
[530.963] ? kmem_cache_alloc+0x12a/0x2d0
[530.973] ? btrfs_submit_metadata_bio+0x63/0x100
[530.984] btrfs_submit_metadata_bio+0xa4/0x100
[530.995] submit_extent_page+0x30f/0x360
[531.004] read_extent_buffer_pages+0x49e/0x6d0
[531.015] ? submit_extent_page+0x360/0x360
[531.025] btree_read_extent_buffer_pages+0x5f/0x150
[531.037] read_tree_block+0x37/0x60
[531.046] read_block_for_search+0x18b/0x410
[531.056] btrfs_search_old_slot+0x198/0x2f0
[531.066] resolve_indirect_ref+0xfe/0x6f0
[531.076] ? ulist_alloc+0x31/0x60
[531.084] ? kmem_cache_alloc_trace+0x12e/0x2b0
[531.095] find_parent_nodes+0x720/0x1830
[531.105] ? ulist_alloc+0x10/0x60
[531.113] iterate_extent_inodes+0xea/0x370
[531.123] ? btrfs_previous_extent_item+0x8f/0x110
[531.134] ? btrfs_search_path_in_tree+0x240/0x240
[531.146] iterate_inodes_from_logical+0x98/0xd0
[531.157] ? btrfs_search_path_in_tree+0x240/0x240
[531.168] btrfs_ioctl_logical_to_ino+0xd9/0x180
[531.179] btrfs_ioctl+0xe2/0x2eb0
This occurs when logical inode resolution takes a tree mod log sequence
number, and then while backref walking hits a rewind on a busy node
which has the following sequence of tree mod log operations (numbers
filled in from a specific example, but they are somewhat arbitrary)
REMOVE_WHILE_FREEING slot 532
REMOVE_WHILE_FREEING slot 531
REMOVE_WHILE_FREEING slot 530
...
REMOVE_WHILE_FREEING slot 0
REMOVE slot 455
REMOVE slot 454
REMOVE slot 453
...
REMOVE slot 0
ADD slot 455
ADD slot 454
ADD slot 453
...
ADD slot 0
MOVE src slot 0 -> dst slot 456 nritems 533
REMOVE slot 455
REMOVE slot 454
REMOVE slot 453
...
REMOVE slot 0
When this sequence gets applied via btrfs_tree_mod_log_rewind, it
allocates a fresh rewind eb, and first inserts the correct key info for
the 533 elements, then overwrites the first 456 of them, then decrements
the count by 456 via the add ops, then rewinds the move by doing a
memmove from 456:988->0:532. We have never written anything past 532, so
that memmove writes garbage into the 0:532 range. In practice, this
results in a lot of fully 0 keys. The rewind then puts valid keys into
slots 0:455 with the last removes, but 456:532 are still invalid.
When search_old_slot uses this eb, if it uses one of those invalid
slots, it can then read the extent buffer and issue a bio for offset 0
which ultimately panics looking up extent mappings.
This bad tree mod log sequence gets generated when the node balancing
code happens to do a balance_node_right followed by a push_node_left
while logging in the tree mod log. Illustrated for ebs L and R (left and
right):
L R
start:
[XXX|YYY|...] [ZZZ|...|...]
balance_node_right:
[XXX|YYY|...] [...|ZZZ|...] move Z to make room for Y
[XXX|...|...] [YYY|ZZZ|...] copy Y from L to R
push_node_left:
[XXX|YYY|...] [...|ZZZ|...] copy Y from R to L
[XXX|YYY|...] [ZZZ|...|...] move Z into emptied space (NOT LOGGED!)
This is because balance_node_right logs a move, but push_node_left
explicitly doesn't. That is because logging the move would remove the
overwritten src < dst range in the right eb, which was already logged
when we called btrfs_tree_mod_log_eb_copy. The correct sequence would
include a move from 456:988 to 0:532 after remove 0:455 and before
removing 0:532. Reversing that sequence would entail creating keys for
0:532, then moving those keys out to 456:988, then creating more keys
for 0:455.
i.e.,
REMOVE_WHILE_FREEING slot 532
REMOVE_WHILE_FREEING slot 531
REMOVE_WHILE_FREEING slot 530
...
REMOVE_WHILE_FREEING slot 0
MOVE src slot 456 -> dst slot 0 nritems 533
REMOVE slot 455
REMOVE slot 454
REMOVE slot 453
...
REMOVE slot 0
ADD slot 455
ADD slot 454
ADD slot 453
...
ADD slot 0
MOVE src slot 0 -> dst slot 456 nritems 533
REMOVE slot 455
REMOVE slot 454
REMOVE slot 453
...
REMOVE slot 0
Fix this to log the move but avoid the double remove by putting all the
logging logic in btrfs_tree_mod_log_eb_copy which has enough information
to detect these cases and properly log moves, removes, and adds. Leave
btrfs_tree_mod_log_insert_move to handle insert_ptr and delete_ptr's
tree mod logging.
(Un)fortunately, this is quite difficult to reproduce, and I was only
able to reproduce it by adding sleeps in btrfs_search_old_slot that
would encourage more log rewinding during ino_to_logical ioctls. I was
able to hit the warning in the previous patch in the series without the
fix quite quickly, but not after this patch.
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
Boris Burkov [Thu, 1 Jun 2023 18:55:13 +0000 (11:55 -0700)]
btrfs: warn on invalid slot in tree mod log rewind
The way that tree mod log tracks the ultimate length of the eb, the
variable 'n', eventually turns up the correct value, but at intermediate
steps during the rewind, n can be inaccurate as a representation of the
end of the eb. For example, it doesn't get updated on move rewinds, and
it does get updated for add/remove in the middle of the eb.
To detect cases with invalid moves, introduce a separate variable called
max_slot which tries to track the maximum valid slot in the rewind eb.
We can then warn if we do a move whose src range goes beyond the max
valid slot.
There is a commented caveat that it is possible to have this value be an
overestimate due to the challenge of properly handling 'add' operations
in the middle of the eb, but in practice it doesn't cause enough of a
problem to throw out the max idea in favor of tracking every valid slot.
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Mon, 22 May 2023 14:51:10 +0000 (16:51 +0200)]
btrfs: disable allocation warnings for compression workspaces
The workspaces for compression are typically much larger than a page and
for high zstd levels in the range of megabytes. There's a fallback to
vmalloc but this can still fail (see the report).
Some of the workspaces are preallocated at module load time so we have a
safe fallback, otherwise when a new workspace is needed it's allocated
but if this fails then the process waits. Which means the warning is
only causing noise and we can use the GFP flag to disable it.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=217466
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 31 May 2023 04:17:39 +0000 (06:17 +0200)]
btrfs: open code need_full_stripe conditions
need_full_stripe is just a somewhat complicated way to say
"op != BTRFS_MAP_READ". Just spell that explicit check out, which makes
a lot of the code currently using the helper easier to understand.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 31 May 2023 04:17:38 +0000 (06:17 +0200)]
btrfs: open code btrfs_map_sblock
btrfs_map_sblock just hard codes three arguments and calls
btrfs_map_sblock. Remove it as it doesn't provide any real value, but
makes following the btrfs_map_block call chains harder.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 31 May 2023 04:17:37 +0000 (06:17 +0200)]
btrfs: rename __btrfs_map_block to btrfs_map_block
Now that the old btrfs_map_block is gone, drop the leading underscores
from __btrfs_map_block.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 31 May 2023 04:17:36 +0000 (06:17 +0200)]
btrfs: remove unused btrfs_map_block
There are no users of btrfs_map_block left, so remove it.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 31 May 2023 04:17:35 +0000 (06:17 +0200)]
btrfs: optimize simple reads in btrfsic_map_block
Pass a smap into __btrfs_map_block so that the usual case of a read that
doesn't require parity raid recovery doesn't need an extra memory
allocation for the btrfs_io_context.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 31 May 2023 04:17:34 +0000 (06:17 +0200)]
btrfs: remove unused BTRFS_MAP_DISCARD
BTRFS_MAP_DISCARD is never set, as REQ_OP_DISCARD is never passed to
btrfs_op() only only checked in two ASSERTS.
Remove it and let the catchall WARN_ON in btrfs_op() deal with accidental
REQ_OP_DISCARDs leaked into btrfs_op(). Last use was in
a4012f06f188
("btrfs: split discard handling out of btrfs_map_block").
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Mon, 3 Apr 2023 22:06:02 +0000 (00:06 +0200)]
btrfs: add xxhash to fast checksum implementations
The implementation of XXHASH is now CPU only but still fast enough to be
considered for the synchronous checksumming, like non-generic crc32c.
A userspace benchmark comparing it to various implementations (patched
hash-speedtest from btrfs-progs):
Block size: 4096
Iterations: 1000000
Implementation: builtin
Units: CPU cycles
NULL-NOP: cycles:
73384294, cycles/i 73
NULL-MEMCPY: cycles:
228033868, cycles/i 228, 61664.320 MiB/s
CRC32C-ref: cycles:
24758559416, cycles/i 24758, 567.950 MiB/s
CRC32C-NI: cycles:
1194350470, cycles/i 1194, 11773.433 MiB/s
CRC32C-ADLERSW: cycles:
6150186216, cycles/i 6150, 2286.372 MiB/s
CRC32C-ADLERHW: cycles:
626979180, cycles/i 626, 22427.453 MiB/s
CRC32C-PCL: cycles:
466746732, cycles/i 466, 30126.699 MiB/s
XXHASH: cycles:
860656400, cycles/i 860, 16338.188 MiB/s
Comparing purely software implementation (ref), current outdated
accelerated using crc32q instruction (NI), optimized implementations by
M. Adler (https://stackoverflow.com/questions/
17645167/implementing-sse-4-2s-crc32c-in-software/
17646775#
17646775)
and the best one that was taken from kernel using the PCLMULQDQ
instruction (PCL).
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 24 May 2023 15:03:17 +0000 (17:03 +0200)]
btrfs: pass the new logical address to split_extent_map
split_extent_map splits off the first chunk of an extent map into a new
one. One of the two users is the zoned I/O completion code that wants to
rewrite the logical block start address right after this split. Pass in
the logical address to be set in the split off first extent_map as an
argument to avoid an extra extent tree lookup for this case.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 24 May 2023 15:03:16 +0000 (17:03 +0200)]
btrfs: defer splitting of ordered extents until I/O completion
The btrfs zoned completion code currently needs an ordered_extent and
extent_map per bio so that it can account for the non-predictable
write location from Zone Append. To archive that it currently splits
the ordered_extent and extent_map at I/O submission time, and then
records the actual physical address in the ->physical field of the
ordered_extent.
This patch instead switches to record the "original" physical address
that the btrfs allocator assigned in spare space in the btrfs_bio,
and then rewrites the logical address in the btrfs_ordered_sum
structure at I/O completion time. This allows the ordered extent
completion handler to simply walk the list of ordered csums and
split the ordered extent as needed. This removes an extra ordered
extent and extent_map lookup and manipulation during the I/O
submission path, and instead batches it in the I/O completion path
where we need to touch these anyway.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 24 May 2023 15:03:15 +0000 (17:03 +0200)]
btrfs: handle completed ordered extents in btrfs_split_ordered_extent
To delay splitting ordered_extents to I/O completion time we need to be
able to handle fully completed ordered extents in
btrfs_split_ordered_extent. Besides a bit of accounting this primarily
involved moving over the csums to the split bio for the range that it
covers, which is simple enough because we always have one
btrfs_ordered_sum per bio.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 24 May 2023 15:03:14 +0000 (17:03 +0200)]
btrfs: atomically insert the new extent in btrfs_split_ordered_extent
Currently there is a small race window in btrfs_split_ordered_extent,
where the reduced old extent can be looked up on the per-inode rbtree
or the per-root list while the newly split out one isn't visible yet.
Fix this by open coding btrfs_alloc_ordered_extent in
btrfs_split_ordered_extent, and holding the tree lock and
root->ordered_extent_lock over the entire tree and extent manipulation.
Note that this introduces new lock ordering because previously
ordered_extent_lock was never held over the tree lock.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 24 May 2023 15:03:13 +0000 (17:03 +0200)]
btrfs: split btrfs_alloc_ordered_extent to allocation and insertion helpers
Split two low-level helpers out of btrfs_alloc_ordered_extent to allocate
and insert the logic extent. The pure alloc helper will be used to
improve btrfs_split_ordered_extent.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 24 May 2023 15:03:11 +0000 (17:03 +0200)]
btrfs: return the new ordered_extent from btrfs_split_ordered_extent
Return the ordered_extent split from the passed in one. This will be
needed to be able to store an ordered_extent in the btrfs_bio.
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 24 May 2023 15:03:10 +0000 (17:03 +0200)]
btrfs: reorder conditions in btrfs_extract_ordered_extent
There is no good reason for doing one before the other in terms of
failure implications, but doing the extent_map split first will
simplify some upcoming refactoring.
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 24 May 2023 15:03:09 +0000 (17:03 +0200)]
btrfs: move split_extent_map to extent_map.c
split_extent_map doesn't have anything to do with the other code in
inode.c, so move it to extent_map.c.
This also allows marking replace_extent_mapping static.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Fri, 9 Jun 2023 05:27:04 +0000 (07:27 +0200)]
btrfs: record orig_physical only for the original bio
btrfs_submit_dev_bio is also called for clone bios that aren't embedded
into a btrfs_bio structure, but previous commit "btrfs: optimize the
logical to physical mapping for zoned writes" added code to assign
btrfs_bio.orig_physical in it.
This is harmless right now as only the single data profile can be used
on zoned devices, but will blow up when the RAID stripe tree is added.
Move it out into the single I/O specific branch in the caller.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 24 May 2023 15:03:08 +0000 (17:03 +0200)]
btrfs: optimize the logical to physical mapping for zoned writes
The current code to store the final logical to physical mapping for a
zone append write in the extent tree is rather inefficient. It first has
to split the ordered extent so that there is one ordered extent per bio,
so that it can look up the ordered extent on I/O completion in
btrfs_record_physical_zoned and store the physical LBA returned by the
block driver in the ordered extent.
btrfs_rewrite_logical_zoned then has to do a lookup in the chunk tree to
see what physical address the logical address for this bio / ordered
extent is mapped to, and then rewrite it in the extent tree.
To optimize this process, we can store the physical address assigned in
the chunk tree to the original logical address and a pointer to
btrfs_ordered_sum structure the in the btrfs_bio structure, and then use
this information to rewrite the logical address in the btrfs_ordered_sum
structure directly at I/O completion time in btrfs_record_physical_zoned.
btrfs_rewrite_logical_zoned then simply updates the logical address in
the extent tree and the ordered_extent itself.
The code in btrfs_rewrite_logical_zoned now runs for all data I/O
completions in zoned file systems, which is fine as there is no remapping
to do for non-append writes to conventional zones or for relocation, and
the overhead for quickly breaking out of the loop is very low.
Because zoned file systems now need the ordered_sums structure to
record the actual write location returned by zone append, allocate dummy
structures without the csum array for them when the I/O doesn't use
checksums, and free them when completing the ordered_extent.
Note that the btrfs_bio doesn't grow as the new field are places into
a union that is so far not used for data writes and has plenty of space
left in it.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 24 May 2023 15:03:07 +0000 (17:03 +0200)]
btrfs: rename the bytenr field in struct btrfs_ordered_sum to logical
btrfs_ordered_sum::bytendr stores a logical address. Make that clear by
renaming it to ->logical.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 24 May 2023 15:03:06 +0000 (17:03 +0200)]
btrfs: mark the len field in struct btrfs_ordered_sum as unsigned
len can't ever be negative, so mark it as an u32 instead of int.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 24 May 2023 15:03:05 +0000 (17:03 +0200)]
btrfs: don't call btrfs_record_physical_zoned for failed append
When a zoned append command fails there is no written address reported,
so don't try to record it.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 24 May 2023 15:03:04 +0000 (17:03 +0200)]
btrfs: optimize out btrfs_is_zoned for !CONFIG_BLK_DEV_ZONED
Add an IS_ENABLED check for CONFIG_BLK_DEV_ZONED in addition to the
run-time check for the zone size. This will allow to make use of
compiler dead code elimination for code guarded by btrfs_is_zoned, and
for example provide just a dangling prototype for a function instead of
adding a stub.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Filipe Manana [Fri, 2 Jun 2023 11:19:42 +0000 (12:19 +0100)]
btrfs: make btrfs_destroy_delayed_refs() return void
btrfs_destroy_delayed_refs() always returns 0 and its single caller does
not check its return value, as it also returns void, and so does the
callers' caller and so on. This is because we are in the transaction abort
path, where we have no way to deal with errors (we are in a critical
situation) and all cleanup of resources works in a best effort fashion.
So make btrfs_destroy_delayed_refs() return void.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Filipe Manana [Mon, 29 May 2023 15:17:06 +0000 (16:17 +0100)]
btrfs: remove unnecessary prototype declarations at disk-io.c
We have a few static functions at disk-io.c for which we have a forward
declaration of their prototype, but it's not needed because all those
functions are defined before they are called, so remove them.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Filipe Manana [Mon, 29 May 2023 15:17:05 +0000 (16:17 +0100)]
btrfs: use a single switch statement when initializing delayed ref head
At init_delayed_ref_head(), we are using two separate if statements to
check the delayed ref head action, and initializing 'must_insert_reserved'
to false twice, once when the variable is declared and once again in an
else branch.
Make this simpler and more straightforward by having a single switch
statement, also moving the comment about a drop action to the
corresponding switch case to make it more clear and eliminating the
duplicated initialization of 'must_insert_reserved' to false.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Filipe Manana [Mon, 29 May 2023 15:17:04 +0000 (16:17 +0100)]
btrfs: use bool type for delayed ref head fields that are used as booleans
There's no point in have several fields defined as 1 bit unsigned int in
struct btrfs_delayed_ref_head, we can instead use a bool type, it makes
the code a bit more readable and it doesn't change the structure size.
So switch them to proper booleans.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Filipe Manana [Mon, 29 May 2023 15:17:03 +0000 (16:17 +0100)]
btrfs: assert correct lock is held at btrfs_select_ref_head()
The function btrfs_select_ref_head() iterates over the red black tree of
delayed reference heads, which is protected by the spinlock in the delayed
refs root. The function doesn't take the lock, it's taken by its single
caller, btrfs_obtain_ref_head(), because it needs to call that function
and btrfs_delayed_ref_lock() in the same critical section (delimited by
that spinlock). So assert at btrfs_select_ref_head() that we are holding
the expected lock.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Filipe Manana [Mon, 29 May 2023 15:17:02 +0000 (16:17 +0100)]
btrfs: get rid of label and goto at insert_delayed_ref()
At insert_delayed_ref() there's no point of having a label and goto in the
case we were able to insert the delayed ref head. We can just add the code
under label to the if statement's body and return immediately, and also
there is no need to track the return value in a variable, we can just
return a literal true or false value directly. So do those changes.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Filipe Manana [Mon, 29 May 2023 15:17:01 +0000 (16:17 +0100)]
btrfs: make insert_delayed_ref() return a bool instead of an int
insert_delayed_ref() can only return 0 or 1, to indicate if the given
delayed reference was added to the head reference or if it was merged
into an existing delayed ref, respectively. So just make it return a
boolean instead.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Filipe Manana [Mon, 29 May 2023 15:17:00 +0000 (16:17 +0100)]
btrfs: use a bool to track qgroup record insertion when adding ref head
We are using an integer as a boolean to track the qgroup record insertion
status when adding a delayed reference head. Since all we need is a
boolean, switch the type from int to bool to make it more obvious.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Filipe Manana [Mon, 29 May 2023 15:16:59 +0000 (16:16 +0100)]
btrfs: remove pointless in_tree field from struct btrfs_delayed_ref_node
The 'in_tree' field is really not needed in struct btrfs_delayed_ref_node,
as we can check whether a reference is in the tree or not simply by
checking its red black tree node member with RB_EMPTY_NODE(), as when we
remove it from the tree we always call RB_CLEAR_NODE(). So remove that
field and use RB_EMPTY_NODE().
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Filipe Manana [Mon, 29 May 2023 15:16:58 +0000 (16:16 +0100)]
btrfs: remove unused is_head field from struct btrfs_delayed_ref_node
The 'is_head' field of struct btrfs_delayed_ref_node is no longer after
commit
d278850eff30 ("btrfs: remove delayed_ref_node from ref_head"),
so remove it.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Filipe Manana [Mon, 29 May 2023 15:16:57 +0000 (16:16 +0100)]
btrfs: reorder some members of struct btrfs_delayed_ref_head
Currently struct delayed_ref_head has its 'bytenr' and 'href_node' members
in different cache lines (even on a release, non-debug, kernel). This is
not optimal because when iterating the red black tree of delayed ref heads
for inserting a new delayed ref head (htree_insert()) we have to pull in 2
cache lines of delayed ref heads we find in a patch, one for the tree node
(struct rb_node) and another one for the 'bytenr' field. The same applies
when searching for an existing delayed ref head (find_ref_head()).
On a release (non-debug) kernel, the structure also has two 4 bytes holes,
which makes it 8 bytes longer than necessary. Its current layout is the
following:
struct btrfs_delayed_ref_head {
u64 bytenr; /* 0 8 */
u64 num_bytes; /* 8 8 */
refcount_t refs; /* 16 4 */
/* XXX 4 bytes hole, try to pack */
struct mutex mutex; /* 24 32 */
spinlock_t lock; /* 56 4 */
/* XXX 4 bytes hole, try to pack */
/* --- cacheline 1 boundary (64 bytes) --- */
struct rb_root_cached ref_tree; /* 64 16 */
struct list_head ref_add_list; /* 80 16 */
struct rb_node href_node __attribute__((__aligned__(8))); /* 96 24 */
struct btrfs_delayed_extent_op * extent_op; /* 120 8 */
/* --- cacheline 2 boundary (128 bytes) --- */
int total_ref_mod; /* 128 4 */
int ref_mod; /* 132 4 */
unsigned int must_insert_reserved:1; /* 136: 0 4 */
unsigned int is_data:1; /* 136: 1 4 */
unsigned int is_system:1; /* 136: 2 4 */
unsigned int processing:1; /* 136: 3 4 */
/* size: 144, cachelines: 3, members: 15 */
/* sum members: 128, holes: 2, sum holes: 8 */
/* sum bitfield members: 4 bits (0 bytes) */
/* padding: 4 */
/* bit_padding: 28 bits */
/* forced alignments: 1 */
/* last cacheline: 16 bytes */
} __attribute__((__aligned__(8)));
This change reorders the 'href_node' and 'refs' members so that we have
the 'href_node' in the same cache line as the 'bytenr' field, while also
eliminating the two holes and reducing the structure size from 144 bytes
down to 136 bytes, so we can now have 30 ref heads per 4K page (on x86_64)
instead of 28. The new structure layout after this change is now:
struct btrfs_delayed_ref_head {
u64 bytenr; /* 0 8 */
u64 num_bytes; /* 8 8 */
struct rb_node href_node __attribute__((__aligned__(8))); /* 16 24 */
struct mutex mutex; /* 40 32 */
/* --- cacheline 1 boundary (64 bytes) was 8 bytes ago --- */
refcount_t refs; /* 72 4 */
spinlock_t lock; /* 76 4 */
struct rb_root_cached ref_tree; /* 80 16 */
struct list_head ref_add_list; /* 96 16 */
struct btrfs_delayed_extent_op * extent_op; /* 112 8 */
int total_ref_mod; /* 120 4 */
int ref_mod; /* 124 4 */
/* --- cacheline 2 boundary (128 bytes) --- */
unsigned int must_insert_reserved:1; /* 128: 0 4 */
unsigned int is_data:1; /* 128: 1 4 */
unsigned int is_system:1; /* 128: 2 4 */
unsigned int processing:1; /* 128: 3 4 */
/* size: 136, cachelines: 3, members: 15 */
/* padding: 4 */
/* bit_padding: 28 bits */
/* forced alignments: 1 */
/* last cacheline: 8 bytes */
} __attribute__((__aligned__(8)));
Running the following fs_mark test shows some significant improvement.
$ cat test.sh
#!/bin/bash
# 15G null block device
DEV=/dev/nullb0
MNT=/mnt/nullb0
FILES=100000
THREADS=$(nproc --all)
FILE_SIZE=0
echo "performance" | \
tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
mkfs.btrfs -f $DEV
mount -o ssd $DEV $MNT
OPTS="-S 0 -L 5 -n $FILES -s $FILE_SIZE -t $THREADS -k"
for ((i = 1; i <= $THREADS; i++)); do
OPTS="$OPTS -d $MNT/d$i"
done
fs_mark $OPTS
umount $MNT
Before this change:
FSUse% Count Size Files/sec App Overhead
10 1200000 0 112631.3
11928055
16 2400000 0 189943.8
12140777
23 3600000 0 150719.2
13178480
50 4800000 0 99137.3
12504293
53 6000000 0 111733.9
12670836
Total files/sec: 664165.5
After this change:
FSUse% Count Size Files/sec App Overhead
10 1200000 0 148589.5
11565889
16 2400000 0 227743.8
11561596
23 3600000 0 191590.5
12550755
30 4800000 0 179812.3
12629610
53 6000000 0 92471.4
12352383
Total files/sec: 840207.5
Measuring the execution times of htree_insert(), in nanoseconds, during
those fs_mark runs:
Before this change:
Range: 0.000 - 940647.000; Mean: 619.733; Median: 548.000; Stddev: 1834.231
Percentiles: 90th: 980.000; 95th: 1208.000; 99th: 2090.000
0.000 - 6.384: 257 |
6.384 - 26.259: 977 |
26.259 - 99.635: 4963 |
99.635 - 370.526: 136800 #############
370.526 - 1370.603: 566110 #####################################################
1370.603 - 5062.704: 24945 ##
5062.704 - 18693.248: 944 |
18693.248 - 69014.670: 211 |
69014.670 - 254791.959: 30 |
254791.959 - 940647.000: 4 |
After this change:
Range: 0.000 - 299200.000; Mean: 587.754; Median: 542.000; Stddev: 1030.422
Percentiles: 90th: 918.000; 95th: 1113.000; 99th: 1987.000
0.000 - 5.585: 163 |
5.585 - 20.678: 452 |
20.678 - 70.369: 1806 |
70.369 - 233.965: 26268 ####
233.965 - 772.564: 333519 #####################################################
772.564 - 2545.771: 91820 ###############
2545.771 - 8383.615: 2238 |
8383.615 - 27603.280: 170 |
27603.280 - 90879.297: 68 |
90879.297 - 299200.000: 12 |
Mean, percentiles, maximum times are all better, as well as a lower
standard deviation.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Qu Wenruo [Tue, 30 May 2023 01:45:28 +0000 (09:45 +0800)]
btrfs: use the same uptodate variable for end_bio_extent_readpage()
In function end_bio_extent_readpage() we call
endio_readpage_release_extent() to unlock the extent io tree.
However we pass PageUptodate(page) as @uptodate parameter for it, while
for previous end_page_read() call, we use a dedicated @uptodate local
variable.
This is not a big deal, as even for subpage cases, either the bio only
covers part of the page, then the @uptodate is always false, and the
subpage ranges can still be merged.
But for the sake of consistency, always use @uptodate variable when
possible.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Qu Wenruo [Tue, 30 May 2023 01:45:27 +0000 (09:45 +0800)]
btrfs: subpage: make alloc_extent_buffer() handle previously uptodate range efficiently
Currently alloc_extent_buffer() would make the extent buffer uptodate if
the corresponding pages are also uptodate.
But this check is only checking PageUptodate, which is fine for regular
cases, but not for subpage cases, as we can have multiple extent buffers
in the same page.
So here we go btrfs_page_test_uptodate() instead.
The old code doesn't cause any problem, but is not efficient, as it
would cause extra metadata read even if the range is already uptodate.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Wed, 3 May 2023 19:08:16 +0000 (21:08 +0200)]
btrfs: print assertion failure report and stack trace from the same line
Assertions reports are split into two parts, the exact file and location
of the condition and then the stack trace printed from
btrfs_assertfail(). This means all the stack traces report the same line
and this is what's typically reported by various tools, making it harder
to distinguish the reports.
[403.2467] assertion failed: refcount_read(&block_group->refs) == 1, in fs/btrfs/block-group.c:4259
[403.2479] ------------[ cut here ]------------
[403.2484] kernel BUG at fs/btrfs/messages.c:259!
[403.2488] invalid opcode: 0000 [#1] PREEMPT SMP KASAN
[403.2493] CPU: 2 PID: 23202 Comm: umount Not tainted 6.2.0-rc4-default+ #67
[403.2499] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552-rebuilt.opensuse.org 04/01/2014
[403.2509] RIP: 0010:btrfs_assertfail+0x19/0x1b [btrfs]
...
[403.2595] Call Trace:
[403.2598] <TASK>
[403.2601] btrfs_free_block_groups.cold+0x52/0xae [btrfs]
[403.2608] close_ctree+0x6c2/0x761 [btrfs]
[403.2613] ? __wait_for_common+0x2b8/0x360
[403.2618] ? btrfs_cleanup_one_transaction.cold+0x7a/0x7a [btrfs]
[403.2626] ? mark_held_locks+0x6b/0x90
[403.2630] ? lockdep_hardirqs_on_prepare+0x13d/0x200
[403.2636] ? __call_rcu_common.constprop.0+0x1ea/0x3d0
[403.2642] ? trace_hardirqs_on+0x2d/0x110
[403.2646] ? __call_rcu_common.constprop.0+0x1ea/0x3d0
[403.2652] generic_shutdown_super+0xb0/0x1c0
[403.2657] kill_anon_super+0x1e/0x40
[403.2662] btrfs_kill_super+0x25/0x30 [btrfs]
[403.2668] deactivate_locked_super+0x4c/0xc0
By making btrfs_assertfail a macro we'll get the same line number for
the BUG output:
[63.5736] assertion failed: 0, in fs/btrfs/super.c:1572
[63.5758] ------------[ cut here ]------------
[63.5782] kernel BUG at fs/btrfs/super.c:1572!
[63.5807] invalid opcode: 0000 [#2] PREEMPT SMP KASAN
[63.5831] CPU: 0 PID: 859 Comm: mount Tainted: G D 6.3.0-rc7-default+ #2062
[63.5868] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a-rebuilt.opensuse.org 04/01/2014
[63.5905] RIP: 0010:btrfs_mount+0x24/0x30 [btrfs]
[63.5964] RSP: 0018:
ffff88800e69fcd8 EFLAGS:
00010246
[63.5982] RAX:
000000000000002d RBX:
ffff888008fc1400 RCX:
0000000000000000
[63.6004] RDX:
0000000000000000 RSI:
ffffffffb90fd868 RDI:
ffffffffbcc3ff20
[63.6026] RBP:
ffffffffc081b200 R08:
0000000000000001 R09:
ffff88800e69fa27
[63.6046] R10:
ffffed1001cd3f44 R11:
0000000000000001 R12:
ffff888005a3c370
[63.6062] R13:
ffffffffc058e830 R14:
0000000000000000 R15:
00000000ffffffff
[63.6081] FS:
00007f7b3561f800(0000) GS:
ffff88806c600000(0000) knlGS:
0000000000000000
[63.6105] CS: 0010 DS: 0000 ES: 0000 CR0:
0000000080050033
[63.6120] CR2:
00007fff83726e10 CR3:
0000000002a9e000 CR4:
00000000000006b0
[63.6137] Call Trace:
[63.6143] <TASK>
[63.6148] legacy_get_tree+0x80/0xd0
[63.6158] vfs_get_tree+0x43/0x120
[63.6166] do_new_mount+0x1f3/0x3d0
[63.6176] ? do_add_mount+0x140/0x140
[63.6187] ? cap_capable+0xa4/0xe0
[63.6197] path_mount+0x223/0xc10
This comes at a cost of bloating the final btrfs.ko module due all the
inlining, as long as assertions are compiled in. This is a must for
debugging builds but this is often enabled on release builds too.
Release build:
text data bss dec hex filename
1251676 20317 16088 1288081 13a791 pre/btrfs.ko
1260612 29473 16088 1306173 13ee3d post/btrfs.ko
DELTA: +8936
CC: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: David Sterba <dsterba@suse.com>
Qu Wenruo [Fri, 26 May 2023 12:30:53 +0000 (20:30 +0800)]
btrfs: subpage: dump extra subpage bitmaps for debug
There is a bug report that assert_eb_page_uptodate() gets triggered for
free space tree metadata.
Without proper dump for the subpage bitmaps it's much harder to debug.
Thus this patch would dump all the subpage bitmaps (split them into
their own bitmaps) for a easier debugging.
The output would look like this:
(Dumped after a tree block got read from disk)
page:
000000006e34bf49 refcount:4 mapcount:0 mapping:
0000000067661ac4 index:0x1d1 pfn:0x110e9
memcg:
ffff0000d7d62000
aops:btree_aops [btrfs] ino:1
flags: 0x8000000000002002(referenced|private|zone=2)
page_type: 0xffffffff()
raw:
8000000000002002 0000000000000000 dead000000000122 ffff00000188bed0
raw:
00000000000001d1 ffff0000c7992700 00000004ffffffff ffff0000d7d62000
page dumped because: btrfs subpage dump
BTRFS warning (device dm-1): start=
30490624 len=16384 page=
30474240 bitmaps: uptodate=4-7 error= dirty= writeback= ordered= checked=
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Tejun Heo [Thu, 25 May 2023 23:33:08 +0000 (13:33 -1000)]
btrfs: use alloc_ordered_workqueue() to create ordered workqueues
BACKGROUND
==========
When multiple work items are queued to a workqueue, their execution order
doesn't match the queueing order. They may get executed in any order and
simultaneously. When fully serialized execution - one by one in the queueing
order - is needed, an ordered workqueue should be used which can be created
with alloc_ordered_workqueue().
However, alloc_ordered_workqueue() was a later addition. Before it, an
ordered workqueue could be obtained by creating an UNBOUND workqueue with
@max_active==1. This originally was an implementation side-effect which was
broken by
4c16bd327c74 ("workqueue: restore WQ_UNBOUND/max_active==1 to be
ordered"). Because there were users that depended on the ordered execution,
5c0338c68706 ("workqueue: restore WQ_UNBOUND/max_active==1 to be ordered")
made workqueue allocation path to implicitly promote UNBOUND workqueues w/
@max_active==1 to ordered workqueues.
While this has worked okay, overloading the UNBOUND allocation interface
this way creates other issues. It's difficult to tell whether a given
workqueue actually needs to be ordered and users that legitimately want a
min concurrency level wq unexpectedly gets an ordered one instead. With
planned UNBOUND workqueue updates to improve execution locality and more
prevalence of chiplet designs which can benefit from such improvements, this
isn't a state we wanna be in forever.
This patch series audits all call sites that create an UNBOUND workqueue w/
@max_active==1 and converts them to alloc_ordered_workqueue() as necessary.
BTRFS
=====
* fs_info->scrub_workers initialized in scrub_workers_get() was setting
@max_active to 1 when @is_dev_replace is set and it seems that the
workqueue actually needs to be ordered if @is_dev_replace. Update the code
so that alloc_ordered_workqueue() is used if @is_dev_replace.
* fs_info->discard_ctl.discard_workers initialized in
btrfs_init_workqueues() was directly using alloc_workqueue() w/
@max_active==1. Converted to alloc_ordered_workqueue().
* fs_info->fixup_workers and fs_info->qgroup_rescan_workers initialized in
btrfs_queue_work() use the btrfs's workqueue wrapper, btrfs_workqueue,
which are allocated with btrfs_alloc_workqueue().
btrfs_workqueue implements automatic @max_active adjustment which is
disabled when the specified max limit is below a certain threshold, so
calling btrfs_alloc_workqueue() with @limit_active==1 yields an ordered
workqueue whose @max_active won't be changed as the auto-tuning is
disabled.
This is rather brittle in that nothing clearly indicates that the two
workqueues should be ordered or btrfs_alloc_workqueue() must disable
auto-tuning when @limit_active==1.
This patch factors out the common btrfs_workqueue init code into
btrfs_init_workqueue() and add explicit btrfs_alloc_ordered_workqueue().
The two workqueues are converted to use the new ordered allocation
interface.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Wed, 24 May 2023 23:04:39 +0000 (01:04 +0200)]
btrfs: drop gfp from parameter extent state helpers
Now that all extent state bit helpers effectively take the GFP_NOFS mask
(and GFP_NOWAIT is encoded in the bits) we can remove the parameter.
This reduces stack consumption in many functions and simplifies a lot of
code.
Net effect on module on a release build:
text data bss dec hex filename
1250432 20985 16088 1287505 13a551 pre/btrfs.ko
1247074 20985 16088 1284147 139833 post/btrfs.ko
DELTA: -3358
Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Wed, 24 May 2023 23:04:37 +0000 (01:04 +0200)]
btrfs: pass NOWAIT for set/clear extent bits as another bit
The only flags we now pass to set_extent_bit/__clear_extent_bit are
GFP_NOFS and GFP_NOWAIT (a few functions handling mappings). This
requires an extra parameter to be passed everywhere but is almost always
the same.
Encode the GFP_NOWAIT as an artificial extent bit and extract the
real bits and gfp mask in the lowest level helpers. Now the passed
gfp mask is not actually used and can be removed.
Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Wed, 24 May 2023 23:04:34 +0000 (01:04 +0200)]
btrfs: drop NOFAIL from set_extent_bit allocation masks
The __GFP_NOFAIL passed to set_extent_bit first appeared in 2010
(commit
f0486c68e4bd9a ("Btrfs: Introduce contexts for metadata
reservation")), without any explanation why it would be needed.
Meanwhile we've updated the semantics of set_extent_bit to handle failed
allocations and do unlock, sleep and retry if needed. The use of the
NOFAIL flag is also an outlier, we never want any of the set/clear
extent bit helpers to fail, they're used for many critical changes like
extent locking, besides the extent state bit changes.
Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Wed, 24 May 2023 23:04:32 +0000 (01:04 +0200)]
btrfs: open code set_extent_bits
This helper calls set_extent_bit with two more parameters set to default
values, but otherwise it's purpose is not clear.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Wed, 24 May 2023 23:04:30 +0000 (01:04 +0200)]
btrfs: open code set_extent_bits_nowait
The helper only passes GFP_NOWAIT as gfp flags and is used two times.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Wed, 24 May 2023 23:04:28 +0000 (01:04 +0200)]
btrfs: open code set_extent_dirty
The helper is used a few times, that it's setting the DIRTY extent bit
is still clear.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Wed, 24 May 2023 23:04:26 +0000 (01:04 +0200)]
btrfs: open code set_extent_new
The helper is used only once.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Wed, 24 May 2023 23:04:23 +0000 (01:04 +0200)]
btrfs: open code set_extent_delalloc
The helper is used once in fs code and a few times in the self test
code.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Wed, 24 May 2023 23:04:21 +0000 (01:04 +0200)]
btrfs: open code set_extent_defrag
The helper is used only once.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Tue, 23 May 2023 08:40:20 +0000 (10:40 +0200)]
btrfs: remove a pointless NULL check in btrfs_lookup_fs_root
btrfs_grab_root already checks for a NULL root itself.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Tue, 23 May 2023 08:40:19 +0000 (10:40 +0200)]
btrfs: convert btrfs_get_global_root to use a switch statement
Use a switch statement instead of an endless chain of if statements
to make the code a little cleaner.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Tue, 23 May 2023 08:40:18 +0000 (10:40 +0200)]
btrfs: fix the btrfs_get_global_root return value
btrfs_grab_root returns either the root or NULL, and the callers of
btrfs_get_global_root expect it to return the same. But all the more
recently added roots instead return an ERR_PTR, so fix this.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Anand Jain [Wed, 24 May 2023 12:02:43 +0000 (20:02 +0800)]
btrfs: add and fix comments in btrfs_fs_devices
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Anand Jain [Wed, 24 May 2023 12:02:42 +0000 (20:02 +0800)]
btrfs: consolidate uuid comparisons in btrfs_validate_super
There are three ways the fsid is validated in btrfs_validate_super():
- verify that super_copy::fsid is the same as fs_devices::fsid
- if the metadata_uuid flag is set, verify if super_copy::metadata_uuid
and fs_devices::metadata_uuid are the same.
- a few lines below, often missed out, verify if dev_item::fsid is the
same as fs_devices::metadata_uuid.
The function btrfs_validate_super() contains multiple if-statements with
memcmp() to check UUIDs. This patch consolidates them into a single
location.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Anand Jain [Wed, 24 May 2023 12:02:41 +0000 (20:02 +0800)]
btrfs: simplify how changed fsid and metadata_uuid is checked
We often check if the metadata_uuid is not the same as fsid, and then we
check if the given fsid matches the metadata_uuid. This patch refactors
this logic into function match_fsid_changed and utilize it.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Anand Jain [Wed, 24 May 2023 12:02:40 +0000 (20:02 +0800)]
btrfs: simplify fsid and metadata_uuid comparisons
Refactor the functions find_fsid() and find_fsid_with_metadata_uuid(),
as they currently share a common set of code to compare the fsid and
metadata_uuid. Create a common helper function, match_fsid_fs_devices().
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Anand Jain [Wed, 24 May 2023 12:02:39 +0000 (20:02 +0800)]
btrfs: return bool from check_tree_block_fsid instead of int
Simplify the return type of check_tree_block_fsid() from int (1 or 0) to
bool. Its only user is interested in knowing the success or failure.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Anand Jain [Wed, 24 May 2023 12:02:38 +0000 (20:02 +0800)]
btrfs: add comment about metadata_uuid in btrfs_fs_devices
Add comment about metadata_uuid in btrfs_fs_devices.
No functional change.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Anand Jain [Wed, 24 May 2023 12:02:37 +0000 (20:02 +0800)]
btrfs: merge calls to alloc_fs_devices in device_list_add
Simplify has_metadata_uuid checks - by localizing the has_metadata_uuid
checked within alloc_fs_devices()'s second argument, it improves the
code readability.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Anand Jain [Wed, 24 May 2023 12:02:36 +0000 (20:02 +0800)]
btrfs: streamline fsid checks in alloc_fs_devices
We currently have redundant checks for the non-null value of fsid
simplify it.
And, no one is using alloc_fs_devices() with a NULL metadata_uuid
while fsid is not NULL, add an assert() to verify this condition.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Anand Jain [Wed, 24 May 2023 12:02:35 +0000 (20:02 +0800)]
btrfs: reduce struct btrfs_fs_devices size by moving fsid_change
Pack bool fsid_change and bool seeding with other bool declarations in the
struct btrfs_fs_devices, approximately 6 bytes is saved, depending on
the config.
before: 512 bytes
after: 496 bytes
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 3 May 2023 15:24:41 +0000 (17:24 +0200)]
btrfs: merge write_one_subpage_eb into write_one_eb
Most of the code in write_one_subpage_eb and write_one_eb is shared,
so merge the two functions into one.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 3 May 2023 15:24:40 +0000 (17:24 +0200)]
btrfs: use per-buffer locking for extent_buffer reading
Instead of locking and unlocking every page or the extent, just add a
new EXTENT_BUFFER_READING bit that mirrors EXTENT_BUFFER_WRITEBACK
for synchronizing threads trying to read an extent_buffer and to wait
for I/O completion.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 3 May 2023 15:24:39 +0000 (17:24 +0200)]
btrfs: stop using lock_extent in btrfs_buffer_uptodate
The only other place that locks extents on the btree inode is
read_extent_buffer_subpage while reading in the partial page for a
buffer. This means locking the extent in btrfs_buffer_uptodate does not
synchronize with anything on non-subpage file systems, and on subpage
file systems it only waits for a parallel read(-ahead) to finish,
which seems to be counter to what the callers actually expect.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 3 May 2023 15:24:38 +0000 (17:24 +0200)]
btrfs: don't check for uptodate pages in read_extent_buffer_pages
The only place that reads in pages and thus marks them uptodate for
the btree inode is read_extent_buffer_pages. Which means that either
pages are already uptodate from an old buffer when creating a new
one in alloc_extent_buffer, or they will be updated by ca call
to read_extent_buffer_pages. This means the checks for uptodate
pages in read_extent_buffer_pages and read_extent_buffer_subpage are
superfluous and can be removed.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 3 May 2023 15:24:37 +0000 (17:24 +0200)]
btrfs: stop using PageError for extent_buffers
PageError is only used to limit the uptodate check in
assert_eb_page_uptodate. But we have a much more useful flag indicating
the exact condition we are about with the EXTENT_BUFFER_WRITE_ERR flag,
so use that instead and help the kernel toward eventually removing
PageError.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 3 May 2023 15:24:36 +0000 (17:24 +0200)]
btrfs: remove the io_pages field in struct extent_buffer
No need to track the number of pages under I/O now that each
extent_buffer is read and written using a single bio. For the
read side we need to grab an extra reference for the duration of
the I/O to prevent eviction, though.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 3 May 2023 15:24:35 +0000 (17:24 +0200)]
btrfs: remove the extent_buffer lookup in btree block checksumming
The checksumming of btree blocks always operates on the entire
extent_buffer, and because btree blocks are always allocated contiguously
on disk they are never split by btrfs_submit_bio.
Simplify the checksumming code by finding the extent_buffer in the
btrfs_bio private data instead of trying to search through the bio_vec.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 3 May 2023 15:24:34 +0000 (17:24 +0200)]
btrfs: use a separate end_io handler for extent_buffer writing
Now that we always use a single bio to write an extent_buffer, the buffer
can be passed to the end_io handler as private data. This allows
to simplify the metadata write end I/O handler, and merge the subpage
end_io handler into the main one.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 3 May 2023 15:24:33 +0000 (17:24 +0200)]
btrfs: don't use btrfs_bio_ctrl for extent buffer writing
The btrfs_bio_ctrl machinery is overkill for writing extent_buffers
as we always operate on PAGE_SIZE chunks (or one smaller one for the
subpage case) that are contiguous and are guaranteed to fit into a
single bio. Replace it with open coded btrfs_bio_alloc, __bio_add_page
and btrfs_submit_bio calls.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 3 May 2023 15:24:32 +0000 (17:24 +0200)]
btrfs: move page locking from lock_extent_buffer_for_io to write_one_eb
Locking the pages in lock_extent_buffer_for_io only for the non-subpage
case is very confusing. Move it to write_one_eb to mirror the subpage
case and simplify the code. Now lock_extent_buffer_for_io does not leave
all the pages locked and each is individually locked/unlocked in
write_one_eb.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 3 May 2023 15:24:31 +0000 (17:24 +0200)]
btrfs: submit a writeback bio per extent_buffer
Stop trying to cluster writes of multiple extent_buffers into a single
bio. There is no need for that as the blk_plug mechanism used all the
way up in writeback_inodes_wb gives us the same I/O pattern even with
multiple bios. Removing the clustering simplifies
lock_extent_buffer_for_io a lot and will also allow passing the eb
as private data to the end I/O handler.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 3 May 2023 15:24:30 +0000 (17:24 +0200)]
btrfs: return bool from lock_extent_buffer_for_io
lock_extent_buffer_for_io never returns a negative error value, so switch
the return value to a simple bool.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
[ keep noinline_for_stack ]
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 3 May 2023 15:24:29 +0000 (17:24 +0200)]
btrfs: do not try to unlock the extent for non-subpage metadata reads
Only subpage metadata reads lock the extent. Don't try to unlock it and
waste cycles in the extent tree lookup for PAGE_SIZE or larger metadata.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 3 May 2023 15:24:28 +0000 (17:24 +0200)]
btrfs: use a separate end_io handler for read_extent_buffer
Now that we always use a single bio to read an extent_buffer, the buffer
can be passed to the end_io handler as private data. This allows
implementing a much simplified dedicated end I/O handler for metadata
reads.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 3 May 2023 15:24:27 +0000 (17:24 +0200)]
btrfs: remove the mirror_num argument to btrfs_submit_compressed_read
Given that read recovery for data I/O is handled in the storage layer,
the mirror_num argument to btrfs_submit_compressed_read is always 0,
so remove it.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 3 May 2023 15:24:26 +0000 (17:24 +0200)]
btrfs: don't use btrfs_bio_ctrl for extent buffer reading
The btrfs_bio_ctrl machinery is overkill for reading extent_buffers
as we always operate on PAGE_SIZE chunks (or one smaller one for the
subpage case) that are contiguous and are guaranteed to fit into a
single bio. Replace it with open coded btrfs_bio_alloc, __bio_add_page
and btrfs_submit_bio calls in a helper function shared between
the subpage and node size >= PAGE_SIZE cases.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 3 May 2023 15:24:25 +0000 (17:24 +0200)]
btrfs: always read the entire extent_buffer
Currently read_extent_buffer_pages skips pages that are already uptodate
when reading in an extent_buffer. While this reduces the amount of data
read, it increases the number of I/O operations as we now need to do
multiple I/Os when reading an extent buffer with one or more uptodate
pages in the middle of it. On any modern storage device, be that hard
drives or SSDs this actually decreases I/O performance. Fortunately
this case is pretty rare as the pages are always initially read together
and then aged the same way. Besides simplifying the code a bit as-is
this will allow for major simplifications to the I/O completion handler
later on.
Note that the case where all pages are uptodate is still handled by an
optimized fast path that does not read any data from disk.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 3 May 2023 15:24:24 +0000 (17:24 +0200)]
btrfs: merge verify_parent_transid and btrfs_buffer_uptodate
verify_parent_transid is only called by btrfs_buffer_uptodate, which
confusingly inverts the return value. Merge the two functions and
reflow the parent_transid so that error handling is in a branch.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 3 May 2023 15:24:23 +0000 (17:24 +0200)]
btrfs: move setting the buffer uptodate out of validate_extent_buffer
Setting the buffer uptodate in a function that is named as a validation
helper is a it confusing. Move the call from validate_extent_buffer to
the one of its two callers that didn't already have a duplicate call
to set_extent_buffer_uptodate.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 3 May 2023 15:24:22 +0000 (17:24 +0200)]
btrfs: subpage: fix error handling in end_bio_subpage_eb_writepage
Call btrfs_page_clear_uptodate instead of ClearPageUptodate to properly
manage the uptodate bit for the subpage case.
Reported-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Christoph Hellwig [Wed, 3 May 2023 15:24:21 +0000 (17:24 +0200)]
btrfs: mark extent_buffer_under_io static
extent_buffer_under_io is only used in extent_io.c, so mark it static.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Qu Wenruo [Thu, 11 May 2023 23:42:05 +0000 (07:42 +0800)]
btrfs: trigger orphan inode cleanup during START_SYNC ioctl
There is an internal error report that scrub found an error in an orphan
inode's data.
However there are very limited ways to cleanup such orphan inodes:
- btrfs_start_pre_rw_mount()
This happens at either mount, or RO->RW switch.
This is not a viable solution for root fs which may not be unmounted
or RO mounted.
Furthermore this doesn't cover every subvolume, it only covers the
currently cached subvolumes.
- btrfs_lookup_dentry()
This happens when we first lookup the subvolume dentry.
But dentry can be cached thus it's not ensured to be triggered every
time.
- create_snapshot()
This only happens for the created snapshot, not the source one.
This means if we didn't trigger orphan items cleanup, there is really no
other way to manually trigger it. Add this step to the START_SYNC ioctl.
This is a slight change in the semantics of the ioctl but as sync can be
potentially slow and is usually paired with WAIT_SYNC ioctl.
The errors are not handled because the main point of the ioctl is the
async commit, orphan cleanup is a side effect.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>