89 Commits

Author SHA1 Message Date
Kent Overstreet
4e92cbb642 bcachefs: More debug code improvements
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:48 -04:00
Kent Overstreet
1c74cec10c bcachefs: Add more debug checks
tracking down a bug where we see a btree node pointer in the wrong node

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:47 -04:00
Kent Overstreet
0b5c9f5940 bcachefs: Set preallocated transaction mem to avoid restarts
this will reduce transaction restarts, from observation of tracepoints.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:47 -04:00
Kent Overstreet
6a747c4683 bcachefs: Add accounting for dirty btree nodes/keys
This lets us improve journal reclaim, so that it now tries to make sure
no more than 3/4s of the btree node cache and btree key cache are dirty
- ensuring the shrinkers can free memory.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:46 -04:00
Kent Overstreet
811d2bcd85 bcachefs: Drop typechecking from bkey_cmp_packed()
This only did anything in two places, and those can just be replaced
wiht bkey_cmp_left_packed()).

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:46 -04:00
Kent Overstreet
7807e14384 bcachefs: Convert various code to printbuf
printbufs know how big the buffer is that was allocated, so we can get
rid of the random PAGE_SIZEs all over the place.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:43 -04:00
Kent Overstreet
760992aac8 bcachefs: Ensure we wake up threads locking node when reusing it
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:43 -04:00
Kent Overstreet
4fe7efa177 bcachefs: Fix an error path
We were missing a 'goto retry' and continuing on with an error pointer.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:43 -04:00
Kent Overstreet
a2b5313a39 bcachefs: Fix a faulty assertion
Now that updates to interior nodes are journalled, we shouldn't be
checking topology of interior nodes until we've finished replaying
updates to that node.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:42 -04:00
Kent Overstreet
fff899b1d9 bcachefs: Mark btree nodes as needing rewrite when not all replicas are RW
This fixes a bug where recovery fails when one of the devices is read
only.

Also - consolidate the "must rewrite this node to insert it" behind a
new btree node flag.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:42 -04:00
Kent Overstreet
937f503605 bcachefs: Use btree reserve when appropriate
Whenever we're doing an update that has pointers, that generally means
we need to do the update in order to release open bucket references - so
we should be using the btree open bucket reserve.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:42 -04:00
Kent Overstreet
2ca88e5ad9 bcachefs: Btree key cache
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>
2023-10-22 17:08:41 -04:00
Kent Overstreet
bd2bb273a0 bcachefs: Don't deadlock when btree node reuse changes lock ordering
Btree node lock ordering is based on the logical key. However, 'struct
btree' may be reused for a different btree node under memory pressure.
This patch uses the new six lock callback to check if a btree node is no
longer the node we wanted to lock before blocking.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:41 -04:00
Kent Overstreet
4efe71a646 bcachefs: Always give out journal pre-res if we already have one
This is better than skipping the journal pre-reservation if we already
have one - we should still acount for the journal reservation we're
going to have to get.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:41 -04:00
Kent Overstreet
966885ee40 bcachefs: Fix a linked list bug
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:41 -04:00
Kent Overstreet
40ca39b564 bcachefs: btree_update_nodes_written() requires alloc reserve
Also, in the btree_update_start() path, if we already have a journal
pre-reservation we don't want to take another - that's a deadlock.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:40 -04:00
Kent Overstreet
00b8ccf707 bcachefs: Interior btree updates are now fully transactional
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>
2023-10-22 17:08:40 -04:00
Kent Overstreet
c823c3390b bcachefs: Factor out bch2_fs_btree_interior_update_init()
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:40 -04:00
Kent Overstreet
bc970cecd8 bcachefs: Fix two more deadlocks
Deadlock on shutdown:

btree_update_nodes_written() unblocks btree nodes from being written;
after doing so, it has to check if they were marked as needing to be
written and if so kick off those writes - if that doesn't happen, we'll
never release journal pins and shutdown will get stuck when flushing the
journal.

There was an error path where this didn't happen, because in the error
path we don't actually want those btree nodes write to happen; however,
we still have to kick off the write path so the journal pins get
released. The btree write path checks if we're in a journal error state
and doesn't do the actual write if we are.

Also - there was another deadlock because btree_update_nodes_written()
was taking the btree update off of the unwritten_list too soon - before
getting a journal reservation, which could fail and have to be retried.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:39 -04:00
Kent Overstreet
5b6d505a77 bcachefs: Fix another deadlock in btree_update_nodes_written()
We also can't be blocking on btree node write locks while holding
btree_interior_update_lock.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:39 -04:00
Kent Overstreet
297604c923 bcachefs: Add a few tracepoints
Transaction restart tracing should probably be overhaulled at some
point.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:38 -04:00
Kent Overstreet
58fb3e519a bcachefs: Fix another deadlock in the btree interior update path
Can't take read locks on btree nodes while holding
btree_interior_update_lock. Also, fix a bug where we were leaking
journal prereservations.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:38 -04:00
Kent Overstreet
0f9dda478f bcachefs: Fix a deadlock on starting an interior btree update
Not legal to block on a journal prereservation with btree locks held.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:38 -04:00
Kent Overstreet
1e3b1f9a22 bcachefs: Fix a debug mode assertion
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:38 -04:00
Kent Overstreet
8707ab0df2 bcachefs: Fix another error path locking bug
btree_update_nodes_written() was leaking a btree node lock on failure to
get a journal reservation.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:38 -04:00
Kent Overstreet
501e1bda3e bcachefs: Fix journalling of interior node updates
We weren't journalling updates done while splitting/compacting nodes -
oops.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:38 -04:00
Kent Overstreet
a0e491c099 bcachefs: Don't allocate memory while holding journal reservation
This fixes a lockdep splat - allocating memory can call
bch2_clear_page_bits() which takes mark_lock.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:37 -04:00
Kent Overstreet
39fb2983c5 bcachefs: Kill bkey_type_successor
Previously, BTREE_ID_INODES was special - inodes were indexed by the
inode field, which meant the offset field of struct bpos wasn't used,
which led to special cases in e.g. the btree iterator code.

Now, inodes in the inodes btree are indexed by the offset field.

Also: prevously min_key was special for extents btrees, min_key for
extents would equal max_key for the previous node. Now, min_key =
bkey_successor() of the previous node, same as non extent btrees.

This means we can completely get rid of
btree_type_sucessor/predecessor.

Also make some improvements to the metadata IO validate/compat code.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:37 -04:00
Kent Overstreet
56a40fbc4e bcachefs: Various fixes for interior update path
The locking was wrong, and we could get a use after free in the error
path where we weren't taking the entrie being freed off the unwritten
list.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:37 -04:00
Kent Overstreet
6357d6071f bcachefs: Journal updates to interior nodes
Previously, the btree has always been self contained and internally
consistent on disk without anything from the journal - the journal just
contained pointers to the btree roots.

However, this meant that btree node split or compact operations - i.e.
anything that changes btree node topology and involves updates to
interior nodes - would require that interior btree node to be written
immediately, which means emitting a btree node write that's mostly empty
(using 4k of space on disk if the filesystemm blocksize is 4k to only
write perhaps ~100 bytes of new keys).

More importantly, this meant most btree node writes had to be FUA, and
consumer drives have a history of slow and/or buggy FUA support - other
filesystes have been bit by this.

This patch changes the interior btree update path to journal updates to
interior nodes, after the writes for the new btree nodes have completed.
Best of all, it turns out to simplify the interior node update path
somewhat.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:37 -04:00
Kent Overstreet
e62d65f2fb bcachefs: trans_commit() path can now insert to interior nodes
This will be needed for the upcoming patches to journal updates to
interior btree nodes.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:37 -04:00
Kent Overstreet
2dac0eae78 bcachefs: Iterator debug code improvements
More aggressively checking iterator invariants, and fixing the resulting
bugs. Also greatly simplifying iter_next() and iter_next_slot() - they
were hyper optimized before, but the optimizations were getting too
brittle.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:36 -04:00
Kent Overstreet
3f58a19763 bcachefs: Journal pin cleanups
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:36 -04:00
Kent Overstreet
00aad62aaf bcachefs: Fix incorrect initialization of btree_node_old_extent_overwrite()
b->level and b->btree_id weren't set when the code was checking
btree_node_is_extents()

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:35 -04:00
Kent Overstreet
ac7c51b218 bcachefs: Seralize btree_update operations at btree_update_nodes_written()
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>
2023-10-22 17:08:35 -04:00
Kent Overstreet
548b3d209f bcachefs: btree_ptr_v2
Add a new btree ptr type which contains the sequence number (random 64
bit cookie, actually) for that btree node - this lets us verify that
when we read in a btree node it really is the btree node we wanted.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:35 -04:00
Kent Overstreet
237e80483a bcachefs: introduce b->hash_val
This is partly prep work for introducing bch_btree_ptr_v2, but it'll
also be a bit of a performance boost by moving the full key out of the
hot part of struct btree.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:35 -04:00
Kent Overstreet
5525f632dc bcachefs: Change btree split threshold to be in u64s
This fixes a bug with very small btree nodes where splitting would end
up with one of the new nodes empty.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:34 -04:00
Kent Overstreet
9626aeb167 bcachefs: Rework iter->pos handling
- Rework some of the helper comparison functions for consistency

- Currently trying to refactor all the logic that's different for
extents in the btree iterator code. The main difference is that for non
extents we search for a key greater than or equal to the search key,
while for extents we search for a key strictly greater than the search
key (iter->pos).

So that logic is now handled by btree_iter_search_key(), which computes
the real search key based on iter->pos and whether or not we're
searching for a key >= or > iter->pos.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:34 -04:00
Kent Overstreet
2d594dfb53 bcachefs: Split out btree_trigger_flags
The trigger flags really belong with individual btree_insert_entries,
not the transaction commit flags - this splits out those  flags and
unifies them with the BCH_BUCKET_MARK flags. Todo - split out
btree_trigger.c from buckets.c

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:33 -04:00
Kent Overstreet
bcd6f3e06f bcachefs: Use KEY_TYPE_deleted whitouts for extents
Previously, partial overwrites of existing extents were handled
implicitly by the btree code; when reading in a btree node, we'd do a
mergesort of the different bsets and detect and fix partially
overlapping extents during that mergesort.

That approach won't work with snapshots: this changes extents to work
like regular keys as far as the btree code is concerned, where a 0 size
KEY_TYPE_deleted whiteout will completely overwrite an existing extent.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:33 -04:00
Kent Overstreet
27b3e52388 bcachefs: Add an assertion to track down a heisenbug
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:33 -04:00
Kent Overstreet
ad44bdc351 bcachefs: bkey noops
For upcoming inline data extents, we're going to need to be able to
shorten the value of existing bkeys in the btree - and to make that work
we're going to be able to need to pad out the space the value previously
took up with something.

This patch changes the various code that iterates over bkeys to handle
k->u64s == 0 as meaning "skip the next 8 bytes".

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:32 -04:00
Justin Husted
928c839cc9 bcachefs: Initialize btree_node flags field in bch2_btree_root_alloc.
Valgrind data indicated that the flags field was only partially
initialized when written to disk.

Signed-off-by: Justin Husted <sigstop@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:30 -04:00
Kent Overstreet
ea3532cbf7 bcachefs: Fix a subtle race in the btree split path
We have to free the old (in memory) btree node _before_ unlocking the
new nodes - else, some other thread with a read lock on the old node
could see stale data after another thread has already updated the new
node.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:29 -04:00
Kent Overstreet
2cbe5cfe27 bcachefs: Rework calling convention for marking overwrites
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:25 -04:00
Kent Overstreet
6e738539cd bcachefs: Improve key marking interface
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:22 -04:00
Kent Overstreet
20bceecb31 bcachefs: More work to avoid transaction restarts
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:22 -04:00
Kent Overstreet
58fbf80834 bcachefs: Delete duplicate code
Also rename for consistency

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:22 -04:00
Kent Overstreet
ed8413fdab bcachefs: improved btree locking tracepoints
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:22 -04:00