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2023-11-17bcachefs: Fix missing locking for dentry->d_parent accessKent Overstreet1-0/+9
Reported-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-15bcachefs: six locks: Fix lost wakeupKent Overstreet1-2/+5
In percpu reader mode, trylock() for read had a lost wakeup: on failure to get the lock, we may have caused a writer to fail to get the lock, because we temporarily elevated the reader count. We need to check for waiters after decrementing the read count - not before. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-15bcachefs: Fix no_data_io mode checksum checkKent Overstreet1-1/+1
In no_data_io mode, we expect data checksums to be wrong - don't want to spew the log with them. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-15bcachefs: Fix bch2_check_nlinks() for snapshotsKent Overstreet1-1/+1
When searching the link table for the matching inode, we were searching for a specific - incorrect - snapshot ID as well, causing us to fail to find the inode. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-15bcachefs: Don't decrease BTREE_ITER_MAX when LOCKDEP=yKent Overstreet1-4/+0
Running with fewer max btree paths doesn't work anymore when replication is enabled - as we've added e.g. the freespace and bucket gens btrees, we naturally end up needing more btree paths. This is an issue with lockdep, we end up taking more locks than lockdep will track (the MAX_LOCKD_DEPTH constant). But bcachefs as merged does not yet support lockdep anyways, so we can leave that for later. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-15bcachefs: Disable debug log statementsKent Overstreet1-0/+7
The journal read path had some informational log statements preperatory for ZNS support - they're not of interest to users, so we can turn them off. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-15bcachefs: Fix missing transaction commitKent Overstreet1-2/+4
In may_delete_deleted_inode(), there's a corner case when a snapshot was taken while we had an unlinked inode: we don't want to delete the inode in the internal (shared) snapshot node, since it might have been reattached in a descendent snapshot. Instead we propagate the key to any snapshot leaves it doesn't exist in, so that it can be deleted there if necessary, and then clear the unlinked flag in the internal node. But we forgot to commit after clearing the unlinked flag, causing us to go into an infinite loop. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-15bcachefs: Fix error path in bch2_mount()Kent Overstreet1-7/+1
This fixes a bug discovered by generic/388 where sb->s_fs_info was NULL while the superblock was still active - the error path was entirely fubar, and was trying to do something unclear and unecessary. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-15bcachefs: Fix potential sleeping during mountDaniel J Blueman1-0/+2
During mount, bcachefs mount option processing may sleep while allocating a string buffer. Fix this by reference counting in order to take the atomic path. Signed-off-by: Daniel J Blueman <daniel@quora.org> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-15bcachefs: Fix iterator leak in may_delete_deleted_inode()Kent Overstreet1-1/+1
may_delete_deleted_inode() was returning without exiting a btree iterator, eventually causing propagate_key_to_snaphot_leaves() to go into an infinite loop hitting btree_trans_too_many_iters(). Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-15bcachefs: Kill journal pre-reservationsKent Overstreet11-275/+19
This deletes the complicated and somewhat expensive journal pre-reservation machinery in favor of just using journal watermarks: when the journal is more than half full, we run journal reclaim more aggressively, and when the journal is more than 3/4s full we only allow journal reclaim to get new journal reservations. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-14bcachefs: Check for nonce offset inconsistency in data_update pathKent Overstreet1-0/+28
We've rarely been seeing a nonce offset inconsistency that doesn't show up in tests: this adds some extra verification code to the data update path that prints out more relevant info when it occurs. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-14bcachefs: Make sure to drop/retake btree locks before reclaimKent Overstreet1-6/+42
We really don't want to be invoking memory reclaim with btree locks held: even aside from (solvable, but tricky) recursion issues, it can cause painful to diagnose performance edge cases. This fixes a recently reported issue in btree_key_can_insert_cached(). Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev> Reported-by: Mateusz Guzik <mjguzik@gmail.com> Fixes: https://lore.kernel.org/linux-bcachefs/CAGudoHEsb_hGRMeWeXh+UF6po0qQuuq_NKSEo+s1sEb6bDLjpA@mail.gmail.com/T/
2023-11-14bcachefs: btree_trans->write_lockedKent Overstreet2-36/+50
As prep work for the next patch to fix a key cache reclaim issue, we need to start tracking whether we're currently holding write locks - so that we can release and retake the before calling into memory reclaim. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-14bcachefs: Run btree key cache shrinker less aggressivelyKent Overstreet2-4/+23
The btree key cache maintains lists of items that have been freed, but can't yet be reclaimed because a bch2_trans_relock() call might find them - we're waiting for SRCU readers to release. Previously, we wouldn't count these items against the number we're attempting to scan for, which would mean we'd evict more live key cache entries - doing quite a bit of potentially unecessary work. With recent work to make sure we don't hold SRCU locks for too long, it should be safe to count all the items on the freelists against number to scan - even if we can't reclaim them yet, we will be able to soon. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-14bcachefs: Split out btree_key_cache_types.hKent Overstreet2-26/+31
More consistent organization. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-14bcachefs: Guard against insufficient devices to create stripesKent Overstreet1-2/+14
We can't create stripes if we don't have enough devices - this manifested as an integer underflow bug later. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-14bcachefs: Fix null ptr deref in bch2_backpointer_get_node()Kent Overstreet1-5/+5
bch2_btree_iter_peek_node() can return a NULL ptr (when the tree is shorter than the search depth); handle this with an early return. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev> Reported-by: Dan Carpenter <dan.carpenter@linaro.org> Fixes: https://lore.kernel.org/linux-bcachefs/5fc3c28b-c232-4ec7-b0ac-4ef220ddf976@moroto.mountain/T/ Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-14bcachefs: Fix multiple -Warray-bounds warningsGustavo A. R. Silva1-1/+1
Transform zero-length array `entries` into a proper flexible-array member in `struct journal_seq_blacklist_table`; and fix the following -Warray-bounds warnings: fs/bcachefs/journal_seq_blacklist.c:148:26: warning: array subscript idx is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=] fs/bcachefs/journal_seq_blacklist.c:150:30: warning: array subscript idx is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=] fs/bcachefs/journal_seq_blacklist.c:154:27: warning: array subscript idx is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=] fs/bcachefs/journal_seq_blacklist.c:176:27: warning: array subscript i is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=] fs/bcachefs/journal_seq_blacklist.c:177:27: warning: array subscript i is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=] fs/bcachefs/journal_seq_blacklist.c:297:34: warning: array subscript i is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=] fs/bcachefs/journal_seq_blacklist.c:298:34: warning: array subscript i is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=] fs/bcachefs/journal_seq_blacklist.c:300:31: warning: array subscript i is outside array bounds of 'struct journal_seq_blacklist_table_entry[0]' [-Warray-bounds=] This results in no differences in binary output. This helps with the ongoing efforts to globally enable -Warray-bounds. Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-14bcachefs: Use DECLARE_FLEX_ARRAY() helper and fix multiple -Warray-bounds ↵Gustavo A. R. Silva1-1/+1
warnings Transform zero-length array `s` into a proper flexible-array member in `struct snapshot_table` via the DECLARE_FLEX_ARRAY() helper; and fix tons of the following -Warray-bounds warnings: fs/bcachefs/snapshot.h:36:21: warning: array subscript <unknown> is outside array bounds of 'struct snapshot_t[0]' [-Warray-bounds=] fs/bcachefs/snapshot.h:36:21: warning: array subscript <unknown> is outside array bounds of 'struct snapshot_t[0]' [-Warray-bounds=] fs/bcachefs/snapshot.c:135:70: warning: array subscript <unknown> is outside array bounds of 'struct snapshot_t[0]' [-Warray-bounds=] fs/bcachefs/snapshot.h:36:21: warning: array subscript <unknown> is outside array bounds of 'struct snapshot_t[0]' [-Warray-bounds=] fs/bcachefs/snapshot.h:36:21: warning: array subscript <unknown> is outside array bounds of 'struct snapshot_t[0]' [-Warray-bounds=] fs/bcachefs/snapshot.h:36:21: warning: array subscript <unknown> is outside array bounds of 'struct snapshot_t[0]' [-Warray-bounds=] This helps with the ongoing efforts to globally enable -Warray-bounds. Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-14bcachefs: Use correct fgf_t type as function argumentKent Overstreet2-2/+2
This quiets a sparse complaint. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-14bcachefs: make bch2_target_to_text_sb staticJiapeng Chong1-1/+1
The bch2_target_to_text_sb are not used outside the file disk_groups.c, so the modification is defined as static. fs/bcachefs/disk_groups.c:583:6: warning: no previous prototype for ‘bch2_target_to_text_sb’. Reported-by: Abaci Robot <abaci@linux.alibaba.com> Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=7144 Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com> Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-11-07Merge tag 'bcachefs-2023-11-5' of https://evilpiepirate.org/git/bcachefsLinus Torvalds107-2291/+3966
Pull more bcachefs updates from Kent Overstreet: "Here's the second big bcachefs pull request. This brings your tree up to date with my master branch, which is what existing bcachefs users are currently running. New features: - rebalance_work btree (and metadata version 1.3): the rebalance thread no longer has to scan to find extents that need processing - big scalability improvement. - sb_errors superblock section: this adds counters for each fsck error type, since filesystem creation, along with the date of the most recent error. It'll get us better bug reports (since users do not typically report errors that fsck was able to fix), and I might add telemetry for this in the future. Fixes include: - multiple snapshot deletion fixes - members_v2 fixups - deleted_inodes btree fixes - copygc thread no longer spins when a device is full but has no fragmented buckets (i.e. rebalance needs to move data around instead) - a fix for a memory reclaim issue with the btree key cache: we're now careful not to hold the srcu read lock that blocks key cache reclaim for too long - an early allocator locking fix, from Brian - endianness fixes, from Brian - CONFIG_BCACHEFS_DEBUG_TRANSACTIONS no longer defaults to y, a big performance improvement on multithreaded workloads" * tag 'bcachefs-2023-11-5' of https://evilpiepirate.org/git/bcachefs: (70 commits) bcachefs: Improve stripe checksum error message bcachefs: Simplify, fix bch2_backpointer_get_key() bcachefs: kill thing_it_points_to arg to backpointer_not_found() bcachefs: bch2_ec_read_extent() now takes btree_trans bcachefs: bch2_stripe_to_text() now prints ptr gens bcachefs: Don't iterate over journal entries just for btree roots bcachefs: Break up bch2_journal_write() bcachefs: Replace ERANGE with private error codes bcachefs: bkey_copy() is no longer a macro bcachefs: x-macro-ify inode flags enum bcachefs: Convert bch2_fs_open() to darray bcachefs: Move __bch2_members_v2_get_mut to sb-members.h bcachefs: bch2_prt_datetime() bcachefs: CONFIG_BCACHEFS_DEBUG_TRANSACTIONS no longer defaults to y bcachefs: Add a comment for BTREE_INSERT_NOJOURNAL usage bcachefs: rebalance_work btree is not a snapshots btree bcachefs: Add missing printk newlines bcachefs: Fix recovery when forced to use JSET_NO_FLUSH journal entry bcachefs: .get_parent() should return an error pointer bcachefs: Fix bch2_delete_dead_inodes() ...
2023-11-05bcachefs: Improve stripe checksum error messageKent Overstreet1-8/+13
We now include the name of the device in the error message - and also increment the number of checksum errors on that device. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: Simplify, fix bch2_backpointer_get_key()Kent Overstreet1-44/+33
- backpointer_not_found() checks backpointers_no_use_write_buffer, no need to do it inbackpointer_get_key(). - always use backpointer_get_node() for pointers to nodes: backpointer_get_key() was sometimes returning the key from the root node unlocked. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: kill thing_it_points_to arg to backpointer_not_found()Kent Overstreet1-7/+6
This can be calculated locally. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: bch2_ec_read_extent() now takes btree_transKent Overstreet3-9/+5
We're not supposed to have more than one btree_trans at a time in a given thread - that causes recursive locking deadlocks. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: bch2_stripe_to_text() now prints ptr gensKent Overstreet1-0/+1
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: Don't iterate over journal entries just for btree rootsKent Overstreet4-40/+29
Small performance optimization, and a bit of a code cleanup too. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: Break up bch2_journal_write()Kent Overstreet1-71/+92
Split up bch2_journal_write() to simplify locking: - bch2_journal_write_pick_flush(), which needs j->lock - bch2_journal_write_prep, which operates on the journal buffer to be written and will need the upcoming buf_lock for synchronization with the btree write buffer flush path Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: Replace ERANGE with private error codesKent Overstreet2-2/+4
We avoid using standard error codes: private, per-callsite error codes make debugging easier. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: bkey_copy() is no longer a macroKent Overstreet4-19/+15
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: x-macro-ify inode flags enumKent Overstreet9-83/+89
This lets us use bch2_prt_bitflags to print them out. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: Convert bch2_fs_open() to darrayKent Overstreet2-32/+34
Open coded dynamic arrays are deprecated. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: Move __bch2_members_v2_get_mut to sb-members.hKent Overstreet2-14/+14
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: bch2_prt_datetime()Kent Overstreet5-26/+22
Improved, better named version of pr_time(). Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: CONFIG_BCACHEFS_DEBUG_TRANSACTIONS no longer defaults to yKent Overstreet1-1/+0
BCACHEFS_DEBUG_TRANSACTIONS is useful, but it's too expensive to have on by default - and it hasn't been coming up in bug reports. Turn it off by default until we figure out a way to make it cheaper. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: Add a comment for BTREE_INSERT_NOJOURNAL usageKent Overstreet4-4/+14
BTREE_INSERT_NOJOURNAL is primarily used for a performance optimization related to inode updates and fsync - document it. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: rebalance_work btree is not a snapshots btreeKent Overstreet5-12/+31
rebalance_work entries may refer to entries in the extents btree, which is a snapshots btree, or they may also refer to entries in the reflink btree, which is not. Hence rebalance_work keys may use the snapshot field but it's not required to be nonzero - add a new btree flag to reflect this. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: Add missing printk newlinesKent Overstreet1-3/+3
This was causing error messages in -tools to not get printed. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: Fix recovery when forced to use JSET_NO_FLUSH journal entryKent Overstreet1-0/+7
When we didn't find anything in the journal that we'd like to use, and we're forced to use whatever we can find - that entry will have been a JSET_NO_FLUSH entry with a garbage last_seq value, since it's not normally used. Initialize it to something sane, for bch2_fs_journal_start(). Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: .get_parent() should return an error pointerKent Overstreet1-3/+0
Delete the useless check for inum == 0; we'll return -ENOENT without it, which is what we want. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: Fix bch2_delete_dead_inodes()Kent Overstreet2-22/+69
- the fsck_err() check for the filesystem being clean was incorrect, causing us to always fail to delete unlinked inodes - if a snapshot had been taken, the unlinked inode needs to be propagated to snapshot leaves so the unlink can happen there - fixed. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: use swab40 for bch_backpointer.bucket_offset bitfieldBrian Foster3-10/+10
The bucket_offset field of bch_backpointer is a 40-bit bitfield, but the bch2_backpointer_swab() helper uses swab32. This leads to inconsistency when an on-disk fs is accessed from an opposite endian machine. As it turns out, we already have an internal swab40() helper that is used from the bch_alloc_v4 swab callback. Lift it into the backpointers header file and use it consistently in both places. Signed-off-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: byte order swap bch_alloc_v4.fragmentation_lru fieldBrian Foster1-0/+1
A simple test to populate a filesystem on one CPU architecture and fsck on an arch of the opposite byte order produces errors related to the fragmentation LRU. This occurs because the 64-bit fragmentation_lru field is not byte-order swapped when reads detect that the on-disk/bset key values were written in opposite byte-order of the current CPU. Update the bch2_alloc_v4 swab callback to handle fragmentation_lru as is done for other multi-byte fields. This doesn't affect existing filesystems when accessed by CPUs of the same endianness because the ->swab() callback is only called when the bset flags indicate an endianness mismatch between the CPU and on-disk data. Signed-off-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: allow writeback to fill bio completelyBrian Foster1-3/+16
The bcachefs folio writeback code includes a bio full check as well as a fixed size check to determine when to split off and submit writeback I/O. The inclusive check of the latter against the limit means that writeback can submit slightly prematurely. This is not a functional problem, but results in unnecessarily split I/Os and extent merging. This can be observed with a buffered write sized exactly to the current maximum value (1MB) and with key_merging_disabled=1. The latter prevents the merge from the second write such that a subsequent check of the extent list shows a 1020k extent followed by a contiguous 4k extent. The purpose for the fixed size check is also undocumented and somewhat obscure. Lift this check into a new helper that wraps the bio check, fix the comparison logic, and add a comment to document the purpose and how we might improve on this in the future. Signed-off-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: fix odebug warn and lockdep splat due to on-stack rhashtableBrian Foster1-10/+14
Guenter Roeck reports a lockdep splat and DEBUG_OBJECTS_WORK related warning when bch2_copygc_thread() initializes its rhashtable. The lockdep splat relates to a warning print caused by the fact that the rhashtable exists on the stack but is not annotated as so. This is something that could be addressed by INIT_WORK_ONSTACK(), but rhashtable doesn't expose that control and probably isnt worth the churn for just one user. Instead, dynamically allocate the buckets_in_flight structure and avoid the splat that way. Reported-by: Guenter Roeck <linux@roeck-us.net> Tested-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: update alloc cursor in early bucket allocatorBrian Foster1-4/+6
A recent bug report uncovered a scenario where a filesystem never runs with freespace_initialized, and therefore the user observes significantly degraded write performance by virtue of running the early bucket allocator. The associated bug aside, the primary cause of the performance drop in this particular instance is that the early bucket allocator does not update the allocation cursor. This means that every allocation walks the alloc btree from the first bucket of the associated device looking for a bucket marked as free space. Update the early allocator code to set the alloc cursor to the last processed position in the tree, similar to how the freelist allocator behaves. With the alloc_cursor being updated, the retry logic also needs to be updated to restart from the beginning of the device when a free bucket is not available between the cursor and the end of the device. Track the restart position in a first_bucket variable to make the code a bit more easily readable and consistent with the freelist allocator. Signed-off-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: serialize on cached key in early bucket allocatorBrian Foster1-3/+25
bcachefs had a transient bug where freespace_initialized was not properly being set, which lead to unexpected use of the early bucket allocator at runtime. This issue has been fixed, but the existence of it uncovered a coherency issue in the early bucket allocation code that is somewhat related to how uncached iterators deal with the key cache. The problem itself manifests as occasional failure of generic/113 due to corruption, often seen as a duplicate backpointer or multiple data types per-bucket error. The immediate cause of the error is a racing bucket allocation along the lines of the following sequence: - Task 1 selects key A in bch2_bucket_alloc_early() and schedules. - Task 2 selects the same key A, but proceeds to complete the allocation and associated I/O, after which it releases the open_bucket. - Task 1 resumes with key A, but does not recognize the bucket is now allocated because the open_bucket has been removed from the hash when it was released in the previous step. This generally shouldn't happen because the allocating task updates the alloc btree key before releasing the bucket. This is not sufficient in this particular instance, however, because an uncached iterator for a cached btree doesn't actually lock the key cache slot when no key exists for a given slot in the cache. Thus the fact that the allocation side updates the cached key means that multiple uncached iters can stumble across the same alloc key and duplicate the bucket allocation as described above. This is something that probably needs a longer term fix in the iterator code. As a short term fix, close the race through explicit use of a cached iterator for likely allocation candidates. We don't want to scan the btree with a cached iterator because that would unnecessarily pollute the cache. This mitigates cache pollution by primarily scanning the tree with an uncached iterator, but closes the race by creating a key cache entry for any prospective slot prior to the bucket allocation attempt (also similar to how _alloc_freelist() works via try_alloc_bucket()). This survives many iterations of generic/113 on a kernel hacked to always use the early bucket allocator. Signed-off-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-05bcachefs: Data move path now uses bch2_trans_unlock_long()Kent Overstreet5-9/+23
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>