Especially in userspace, we sometime run into resource exhaustion issues
with starting up threads after mark and sweep/fsck.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This fixes a regression from the patch
bcachefs: Fix copygc dying on startup
In general only the allocator thread itself should be updating
ca->allocator_state, the thread waking up the allocator setting it is an
ugly hack only needed to avoid racing with the copygc threads when we're
first starting up.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
We have a separate mechanism for ratelimiting copygc now - the pd
controller has only been causing problems.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
We're seeing failures to mount because of a failure to start the
allocator threads, which currently happens fairly late in the mount
process, after walking all metadata, and kthread_create() fails if
something has tried to kill the mount process, which is probably not
what we want.
This patch avoids this issue by creating, but not starting, the
allocator threads when we preallocate all of our other in memory data
structures.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
When the replicas mechanism was added, for tracking data by which drives
it's replicated on, the check for whether we have sufficient devices was
never updated to make use of it. This patch finally does that.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This fixes some arithmetic bugs in "bcachefs: Journal updates to dev
usage" - additionally, it cleans things up by switching everything that
goes in every journal entry to the journal_entry_res mechanism.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This eliminates the need to scan every bucket to regenerate dev_usage at
mount time.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Originally, bcachefs - going back to bcache - stored, for each bucket, a
16 bit counter corresponding to how long it had been since the bucket
was read from. But, this required periodically rescaling counters on
every bucket to avoid wraparound. That wasn't an issue in bcache, where
we'd perodically rewrite the per bucket metadata all at once, but in
bcachefs we're trying to avoid having to walk every single bucket.
This patch switches to persisting 64 bit io clocks, corresponding to the
64 bit bucket timestaps introduced in the previous patch with
KEY_TYPE_alloc_v2.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Some errors may need to be fixed in order for GC to successfully run -
walk and mark all metadata. But we can't start the allocators and do
normal btree updates until after GC has completed, and allocation
information is known to be consistent, so we need a different method of
doing btree updates.
Fortunately, we already have code for walking the btree while overlaying
keys from the journal to be replayed. This patch adds an update path
that adds keys to the list of keys to be replayed by journal replay, and
also fixes up iterators.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
More work towards getting rid of the in memory struct bucket: this path
adds code for marking superblock and journal buckets via the btree, and
uses it in the device add and journal resize paths.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This is to make it more amenable for serialization.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
There was a race: btree node writes drop their reference on journal pins
before clearing the btree_node_write_in_flight flag.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Various filesystem usage counters are kept in percpu counters, with one
set per in flight journal buffer. Right now all the code that deals with
it assumes that there's only two buffers/sets of counters, but the
number of journal bufs is getting increased to 4 in the next patch - so
refactor that code to not assume a constant.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
We allocate a lot of these, and we're seeing sporading OOMs - this will
help with tracking those down.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Previous varint implementation used by the inode code was not nearly as
fast as it could have been; partly because it was attempting to encode
integers up to 96 bits (for timestamps) but this meant that encoding and
decoding the length required a table lookup.
Instead, we'll just encode timestamps greater than 64 bits as two
separate varints; this will make decoding/encoding of inodes
significantly faster overall.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Allocating our array of btree iters is a big enough allocation that it
hits the buddy allocator, and we're seeing lots of lock contention.
Sticking a single element buffer in front of it should help.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This shards new inodes into different btree nodes by using the processor
ID for the high bits of the new inode number. Much faster than the
previous inode create optimization - this also helps with sharding in
the other btrees that index by inode number.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
With the btree key cache code, journal reclaim now has a lot more work
to do. It could be the case that after journal reclaim has finished one
iteration there's already more work to do, so put it in a loop to check
for that.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
On workloads that do a lot of multithreaded creates all at once, lock
contention on the inodes btree turns out to still be an issue.
This patch adds a small buffer of inode numbers that are known to be
free, so that we can avoid touching the btree on every create. Also,
this changes inode creates to update via the btree key cache for the
initial create.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This fixes a bug where the clock hands in the journal and superblock
didn't match, because we were still incrementing the read clock hand
while read-only.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Now that we've got transactional alloc info updates (and have for
awhile), we don't need to write it out on shutdown, and we don't need to
write it out on startup except when GC found errors - this is a big
improvement to mount/unmount performance.
This patch also fixes a few bugs where we weren't writing out alloc
info (on new filesystems, and new devices) and should have been.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
The copygc threads errors out and makes the filesystem go RO if it ever
tries to run and discovers it has no reserve allocated - which is a
problem if it races with the allocator thread and its reserve hasn't
been filled yet.
The allocator thread doesn't start filling the copygc reserve until
after BCH_FS_STARTED has been set, so make sure to wake up the allocator
threads after setting that and before starting copygc.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
At some point bch2_fs_alloc() was changed to always call bch2_fs_free()
in the error path, which means we need c->cl to always be initialized.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
There was a long standing race in the mount/unmount code - the VFS
intends for mount/unmount synchronizatino to be handled by the list of
superblocks, but we were still holding devices open after tearing down
our superblock in the unmount path.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Also - make sure to show the devices we actually have open in /proc
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Previously, we would start doing btree updates before writing the first
journal entry; if this was after an unclean shutdown, this could cause
those btree updates to not be blacklisted.
Also, move some code to headers for userspace debug tools.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Per device copygc threads don't move data to different devices and they
make fragmentation works - they don't make much sense anymore.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This is mainly to solve a lock ordering issue, and also simplifies the
code a bit.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Soon we'll be able to modify existing stripes - replacing empty blocks
with new blocks and new p/q blocks. This patch updates the trigger code
to handle pointers changing in an existing stripe; also, it
significantly improves how the stripes heap works, which means we can
get rid of the stripe creation/deletion lock.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This introduces a new kind of btree iterator, cached iterators, which
point to keys cached in a hash table. The cache also acts as a write
cache - in the update path, we journal the update but defer updating the
btree until the cached entry is flushed by journal reclaim.
Cache coherency is for now up to the users to handle, which isn't ideal
but should be good enough for now.
These new iterators will be used for updating inodes and alloc info (the
alloc and stripes btrees).
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
It's not needed anymore since we can now write to buckets before
updating the alloc btree.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Now that interior btree updates are fully transactional, we don't need
to write out alloc info in a loop. However, interior btree updates do
put more things in the journal, so we still need a loop in the RO
sequence.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
We now update the alloc info (bucket sector counts) atomically with
journalling the update to the interior btree nodes, and we also set new
btree roots atomically with the journalled part of the btree update.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
When updates to interior nodes started being journalled, that meant that
after an unclean shutdown, until journal replay is done we can't walk
the btree without overlaying the updates from the journal.
The initial btree gc was changed to walk the btree overlaying keys from
the journal - but bch2_alloc_read() and bch2_stripes_read() were missed.
Major whoops...
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Previously, there was at least one error path where we could mark the
filesystem clean when we hadn't sucessfully written out alloc info.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
- Always pass BTREE_INSERT_USE_RESERVE when writing alloc btree keys
- Don't strand buckest on the copygc freelist until after recovery is
done and we're starting copygc.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This will be used by the userspace debug tools.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This will help for debugging hangs during unmount
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Prep work for journalling updates to interior nodes - enforcing ordering
will greatly simplify those changes.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
The device remove test was sporadically failing, because we hadn't
finished dropping btree sector counts for the device when
bch2_replicas_gc2() was called - mainly due to in flight journal writes.
We don't yet have a good mechanism for flushing the counts that
correspend to open journal entries yet.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
BTREE_INSERT_LAZY_RW was added for this since this code was written; use
it instead.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Long overdue cleanup - this converts btree_node_iter_large uses to
sort_iter.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This implements code for storing small bkeys on the stack and allocating
out of a mempool if they're too big.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
We weren't checking for errors when trying to delet stripes, which meant
ec_stripe_delete_work() would spin trying to delete the same stripe over
and over.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
mark_lock is a frequently taken lock, and there's also potential for
deadlocks since currently bch2_clear_page_bits which is called from
memory reclaim has to take it to drop disk reservations.
The disk reservation get path takes it when it recalculates the number
of sectors known to be available, but it's not really needed for
consistency. We just want to make sure we only have one thread updating
the sectors_available count, which we can do with a dedicated mutex.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Now, we store blacklisted journal sequence numbers in the superblock,
not the journal: this helps to greatly simplify the code, and more
importantly it's now implemented in a way that doesn't require all btree
nodes to be visited before starting the journal - instead, we
unconditionally blacklist the next 4 journal sequence numbers after an
unclean shutdown.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
In flight btree updates could update alloc info until they're flushed -
so we have to try writing again after they've been flushed.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
- Does not persist alloc info for stripes yet
- Also does not yet include filesystem block/sector counts yet, from
struct fs_usage
- Not made use of just yet
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
journal reclaim writes btree nodes, which can end up waiting for in
flight btree writes to complete, and btree write completions run out of
workqueues - so we can't run out of the same workqueue or we risk
deadlock
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
this lets us get rid of a lot of extra switch statements - in a lot of
places we dispatch on the btree node type, and then the key type, so
this is a nice cleanup across a lot of code.
Also improve the on disk format versioning stuff.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This means we can now use gc to verify the allocation information -
important for testing persistant alloc info
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This way the last mount time is actually meaningful instead of just being
various times from 1970 (which happens with the monotonic clock).
Also, roundup_pow_of_two() is undefined when passed in 0, so check before
calling it.
Signed-off-by: Tim Schlueter <schlueter.tim@linux.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Due to compression, the different replicas of a replicated extent don't
necessarily have to take up the same amount of space - so replicated
data sector counts shouldn't be stored divided by the number of
replicas.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Initially forked from drivers/md/bcache, bcachefs is a new copy-on-write
filesystem with every feature you could possibly want.
Website: https://bcachefs.org
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
