This introduces bch2_bucket_sectors() and bch2_bucket_sectors_dirty(),
prep work for separately accounting stripe sectors.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This fixes a bug where going read-only was taking longer than it should
have due to copygc forgetting to check kthread_should_stop()
Additionally: fix a missing is_kthread check in bch2_move_ratelimit().
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
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>
data_progress_list is gone - it was redundant with moving_context_list
The upcoming rebalance rewrite is going to have it using two different
move_stats objects with the same moving_context, depending on whether
it's scanning or using the rebalance_work btree - this patch plumbs
stats around a bit differently so that will work.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
btree_trans and moving_context are used together, and having the
moving_context owns the transaction object reduces some plumbing.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
We're using more stack than we'd like in a number of functions, and
btree_trans is the biggest object that we stack allocate.
But we have to do a heap allocatation to initialize it anyways, so
there's no real downside to heap allocating the entire thing.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
When building bcachefs for 32-bit ARM, there is a warning when using
max() to compare an expression involving 'size_t' with an 'unsigned
long' literal:
fs/bcachefs/movinggc.c:159:21: error: comparison of distinct pointer types ('typeof (16UL) *' (aka 'unsigned long *') and 'typeof (buckets_in_flight->nr / 4) *' (aka 'unsigned int *')) [-Werror,-Wcompare-distinct-pointer-types]
159 | size_t nr_to_get = max(16UL, buckets_in_flight->nr / 4);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:76:19: note: expanded from macro 'max'
76 | #define max(x, y) __careful_cmp(x, y, >)
| ^~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:38:24: note: expanded from macro '__careful_cmp'
38 | __builtin_choose_expr(__safe_cmp(x, y), \
| ^~~~~~~~~~~~~~~~
include/linux/minmax.h:28:4: note: expanded from macro '__safe_cmp'
28 | (__typecheck(x, y) && __no_side_effects(x, y))
| ^~~~~~~~~~~~~~~~~
include/linux/minmax.h:22:28: note: expanded from macro '__typecheck'
22 | (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
| ~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~
1 error generated.
On 64-bit architectures, size_t is 'unsigned long', so there is no
warning when comparing these two expressions. Use max_t(size_t, ...) for
this situation, eliminating the warning.
Fixes: dd49018737d4 ("bcachefs: Rhashtable based buckets_in_flight for copygc")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
More reorganization, this splits up io.c into
- io_read.c
- io_misc.c - fallocate, fpunch, truncate
- io_write.c
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Now that we have journal watermarks and alloc watermarks unified,
BTREE_INSERT_USE_RESERVE is redundant and can be deleted.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This unifies JOURNAL_WATERMARK with BCH_WATERMARK; we're working towards
specifying watermarks once in the transaction commit path.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
As with previous conversions, replace -ENOENT uses with more informative
private error codes.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Introduce new helpers for a common pattern:
bch2_trans_iter_init();
bch2_btree_iter_peek_slot();
- bch2_bkey_get_iter_type() returns -ENOENT if it doesn't find a key of
the correct type
- bch2_bkey_get_val_typed() copies the val out of the btree to a
(typically stack allocated) variable; it handles the case where the
value in the btree is smaller than the current version of the type,
zeroing out the remainder.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
With backpointers, it's now impossible for bch2_evacuate_bucket() to be
completely reliable: it can race with an extent being partially
overwritten or split, which needs a new write buffer flush for the
backpointer to be seen.
This shouldn't be a real issue in practice; the previous patch added a
new tracepoint so we'll be able to see more easily if it is.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Previously, copygc used a fifo for tracking buckets in flight - this had
the disadvantage of being fixed size, since we pass references to
elements into the move code.
This restructures it to be a hash table and linked list, since with
erasure coding we need to be able to pipeline across an arbitrary number
of buckets.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This just adds a line for how long copygc has been waiting to sysfs
copygc_wait, helpful for debugging why copygc isn't running.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
We're not supposed to have nested (locked) btree_trans on the stack:
this means copygc shutdown needs to exit our btree_trans before exiting
the move_ctxt, which calls bch2_write().
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
BTREE_ITER_CACHED should really be the default for cached btrees - this
is an easy mistake to make.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This improves copygc pipelining across multiple buckets: we now track
each in flight bucket we're evacuating, with separate moving_contexts.
This means that whereas previously we had to wait for outstanding moves
to complete to ensure we didn't try to evacuate the same bucket twice,
we can now just check buckets we want to evacuate against the pending
list.
This also mean we can run the verify_bucket_evacuated() check without
killing pipelining - meaning it can now always be enabled, not just on
debug builds.
This is going to be important for the upcoming erasure coding work,
where moving IOs that are being erasure coded will now skip the initial
replication step; instead the IOs will wait on the stripe to complete.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Currently, we don't use bucket data type for tracking whether buckets
are part of a stripe; parity buckets are BCH_DATA_parity, but data
buckets in a stripe are BCH_DATA_user. There's a separate counter,
buckets_ec, outside the BCH_DATA_TYPES system for tracking number of
buckets on a device that are part of a stripe.
The trouble with this approach is that it's too coarse grained, and we
need better information on fragmentation for debugging copygc.
With this patch, data buckets in a stripe are now tracked as
BCH_DATA_stripe buckets.
This doesn't yet differentiate between erasure coded and non-erasure
coded data in a stripe bucket, nor do we yet track empty data buckets in
stripes.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Now that we have much more efficient updates to the LRU btree, this
patch adds a new LRU that indexes buckets by fragmentation.
This means copygc no longer has to scan every bucket to find buckets
that need to be evacuated.
Changes:
- A new field in bch_alloc_v4, fragmentation_lru - this corresponds to
the bucket's position in the fragmentation LRU. We add a new field
for this instead of calculating it as needed because we may make the
fragmentation LRU optional; this field indicates whether a bucket is
on the fragmentation LRU.
Also, zoned devices will introduce variable bucket sizes; explicitly
recording the LRU position will be safer for them.
- A new copygc path for using the fragmentation LRU instead of
scanning every bucket and building up an in-memory heap.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Previously, copygc needed to walk the entire extents & reflink btrees to
find extents that needed to be moved.
Now that we have backpointers, this patch implements
bch2_evacuate_bucket() in the move code, which copygc now uses for
evacuating mostly empty buckets.
Also, thanks to the new backpointers code, copygc can now move btree
nodes.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This separates out the slowpath into a separate function, and inlines
bch2_alloc_v4_mut into bch2_trans_start_alloc_update(), the main place
it's called.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This isn't actually an error condition, this just indicates a normal
shutdown - no reason for these to be in the log.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
- Marking a non-static function as inline doesn't actually work and is
now causing problems - drop that
- Introduce BCACHEFS_LOG_PREFIX for when we want to prefix log messages
with bcachefs (filesystem name)
- Userspace doesn't have real percpu variables (maybe we can get this
fixed someday), put an #ifdef around bch2_disk_reservation_add()
fastpath
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Also, do some reorganizing/renaming, convert atomic counters in bch_fs
to persistent counters, and add a few missing counters.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
- add bch2_moving_ctxt_(init|exit)
- split out __bch2_evacutae_bucket() which takes an existing
moving_ctxt, this will be used for improving copygc performance by
pipelining across multiple buckets
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
move_ratelimit() now has a bool that specifies whether we want to
wait for copygc to finish.
When copygc is running, we're probably low on free buckets instead
of consuming the remaining buckets, we want to wait for copygc to
finish.
This should help with performance, and run away bucket fragmentation.
Signed-off-by: Daniel Hill <daniel@gluo.nz>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This patch significantly cleans up and simplifies the data_update
interface. Instead of only being able to specify a single pointer by
device to rewrite, we're now able to specify any or all of the pointers
in the original extent to be rewrited, as a bitmask.
data_cmd is no more: the various pred functions now just return true if
the extent should be moved/updated. All the data_update path does is
rewrite existing replicas, or add new ones.
This fixes a bug where with background compression on replicated
filesystems, where rebalance -> data_update would incorrectly drop the
wrong old replica, and keep trying to recompress an extent pointer and
each time failing to drop the right replica. Oops.
Now, the data update path doesn't look at the io options to decide which
pointers to keep and which to drop - it only goes off of the
data_update_options passed to it.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
This improves the "copygc requested to run but no buckets found" to show
the device that requires copygc to be run on - we'll definitely need to
improve this more.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Previously, we were missing accounting for buckets in need_gc_gens and
need_discard states. This matters because buckets in those states need
other btree operations done before they can be used, so they can't be
conuted when checking current number of free buckets against the
allocation watermark.
Also, we weren't directly counting free buckets at all. Now, data type 0
== BCH_DATA_free, and free buckets are counted; this means we can get
rid of the separate (poorly defined) count of unavailable buckets.
This is a new on disk format version, with upgrade and fsck required for
the accounting changes.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Now that we have new persistent data structures for the allocator, this
patch converts the allocator to use them.
Now, foreground bucket allocation uses the freespace btree to find
buckets to allocate, instead of popping buckets off the freelist.
The background allocator threads are no longer needed and are deleted,
as well as the allocator freelists. Now we only need background tasks
for invalidating buckets containing cached data (when we are low on
empty buckets), and for issuing discards.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This introduces a new alloc key which doesn't use varints. Soon we'll be
adding backpointers and storing them in alloc keys, which means our
pack/unpack workflow for alloc keys won't really work - we'll need to be
mutating alloc keys in place.
Instead of bch2_alloc_unpack(), we now have bch2_alloc_to_v4() that
converts older types of alloc keys to v4 if needed.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Since journal reclaim -> btree key cache flushing may require the
allocation of new btree nodes, it has an implicit dependency on copygc
in order to make forward progress - so we should avoid blocking copygc
unless the journal is really close to full.
This introduces watermarks to replace our single MAY_GET_UNRESERVED bit
in the journal, and adds a watermark for copygc and plumbs it through.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This converts the copygc code to use the alloc btree directly to find
buckets that need to be evacuated instead of the in-memory bucket array,
which is finally going away soon.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Previously, bucket fragmentation was considered to be bucket size -
total amount of live data, both dirty and cached.
This meant that if a bucket was full but only a small amount of data in
it was dirty - the rest cached, we'd get stuck: copygc wouldn't move the
dirty data out of the bucket and the allocator wouldn't be able to
invalidate and drop the cached data.
This changes fragmentation to exclude cached data, so that copygc will
evacuate these buckets and copygc/the allocator will always be able to
make forward progress.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
