diff options
Diffstat (limited to 'fs/bcachefs/btree_cache.c')
| -rw-r--r-- | fs/bcachefs/btree_cache.c | 1516 |
1 files changed, 0 insertions, 1516 deletions
diff --git a/fs/bcachefs/btree_cache.c b/fs/bcachefs/btree_cache.c deleted file mode 100644 index 83c9860e6b82..000000000000 --- a/fs/bcachefs/btree_cache.c +++ /dev/null @@ -1,1516 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 - -#include "bcachefs.h" -#include "bbpos.h" -#include "bkey_buf.h" -#include "btree_cache.h" -#include "btree_io.h" -#include "btree_iter.h" -#include "btree_locking.h" -#include "debug.h" -#include "errcode.h" -#include "error.h" -#include "journal.h" -#include "trace.h" - -#include <linux/prefetch.h> -#include <linux/sched/mm.h> -#include <linux/swap.h> - -const char * const bch2_btree_node_flags[] = { - "typebit", - "typebit", - "typebit", -#define x(f) [BTREE_NODE_##f] = #f, - BTREE_FLAGS() -#undef x - NULL -}; - -void bch2_recalc_btree_reserve(struct bch_fs *c) -{ - unsigned reserve = 16; - - if (!c->btree_roots_known[0].b) - reserve += 8; - - for (unsigned i = 0; i < btree_id_nr_alive(c); i++) { - struct btree_root *r = bch2_btree_id_root(c, i); - - if (r->b) - reserve += min_t(unsigned, 1, r->b->c.level) * 8; - } - - c->btree_cache.nr_reserve = reserve; -} - -static inline size_t btree_cache_can_free(struct btree_cache_list *list) -{ - struct btree_cache *bc = container_of(list, struct btree_cache, live[list->idx]); - - size_t can_free = list->nr; - if (!list->idx) - can_free = max_t(ssize_t, 0, can_free - bc->nr_reserve); - return can_free; -} - -static void btree_node_to_freedlist(struct btree_cache *bc, struct btree *b) -{ - BUG_ON(!list_empty(&b->list)); - - if (b->c.lock.readers) - list_add(&b->list, &bc->freed_pcpu); - else - list_add(&b->list, &bc->freed_nonpcpu); -} - -static void __bch2_btree_node_to_freelist(struct btree_cache *bc, struct btree *b) -{ - BUG_ON(!list_empty(&b->list)); - BUG_ON(!b->data); - - bc->nr_freeable++; - list_add(&b->list, &bc->freeable); -} - -void bch2_btree_node_to_freelist(struct bch_fs *c, struct btree *b) -{ - struct btree_cache *bc = &c->btree_cache; - - mutex_lock(&bc->lock); - __bch2_btree_node_to_freelist(bc, b); - mutex_unlock(&bc->lock); - - six_unlock_write(&b->c.lock); - six_unlock_intent(&b->c.lock); -} - -void __btree_node_data_free(struct btree *b) -{ - BUG_ON(!list_empty(&b->list)); - BUG_ON(btree_node_hashed(b)); - - /* - * This should really be done in slub/vmalloc, but we're using the - * kmalloc_large() path, so we're working around a slub bug by doing - * this here: - */ - if (b->data) - mm_account_reclaimed_pages(btree_buf_bytes(b) / PAGE_SIZE); - if (b->aux_data) - mm_account_reclaimed_pages(btree_aux_data_bytes(b) / PAGE_SIZE); - - EBUG_ON(btree_node_write_in_flight(b)); - - clear_btree_node_just_written(b); - - kvfree(b->data); - b->data = NULL; -#ifdef __KERNEL__ - kvfree(b->aux_data); -#else - munmap(b->aux_data, btree_aux_data_bytes(b)); -#endif - b->aux_data = NULL; -} - -static void btree_node_data_free(struct btree_cache *bc, struct btree *b) -{ - BUG_ON(list_empty(&b->list)); - list_del_init(&b->list); - - __btree_node_data_free(b); - - --bc->nr_freeable; - btree_node_to_freedlist(bc, b); -} - -static int bch2_btree_cache_cmp_fn(struct rhashtable_compare_arg *arg, - const void *obj) -{ - const struct btree *b = obj; - const u64 *v = arg->key; - - return b->hash_val == *v ? 0 : 1; -} - -static const struct rhashtable_params bch_btree_cache_params = { - .head_offset = offsetof(struct btree, hash), - .key_offset = offsetof(struct btree, hash_val), - .key_len = sizeof(u64), - .obj_cmpfn = bch2_btree_cache_cmp_fn, - .automatic_shrinking = true, -}; - -static int btree_node_data_alloc(struct bch_fs *c, struct btree *b, gfp_t gfp) -{ - BUG_ON(b->data || b->aux_data); - - gfp |= __GFP_ACCOUNT|__GFP_RECLAIMABLE; - - b->data = kvmalloc(btree_buf_bytes(b), gfp); - if (!b->data) - return bch_err_throw(c, ENOMEM_btree_node_mem_alloc); -#ifdef __KERNEL__ - b->aux_data = kvmalloc(btree_aux_data_bytes(b), gfp); -#else - b->aux_data = mmap(NULL, btree_aux_data_bytes(b), - PROT_READ|PROT_WRITE|PROT_EXEC, - MAP_PRIVATE|MAP_ANONYMOUS, 0, 0); - if (b->aux_data == MAP_FAILED) - b->aux_data = NULL; -#endif - if (!b->aux_data) { - kvfree(b->data); - b->data = NULL; - return bch_err_throw(c, ENOMEM_btree_node_mem_alloc); - } - - return 0; -} - -static struct btree *__btree_node_mem_alloc(struct bch_fs *c, gfp_t gfp) -{ - struct btree *b; - - b = kzalloc(sizeof(struct btree), gfp); - if (!b) - return NULL; - - bkey_btree_ptr_init(&b->key); - INIT_LIST_HEAD(&b->list); - INIT_LIST_HEAD(&b->write_blocked); - b->byte_order = ilog2(c->opts.btree_node_size); - return b; -} - -struct btree *__bch2_btree_node_mem_alloc(struct bch_fs *c) -{ - struct btree *b = __btree_node_mem_alloc(c, GFP_KERNEL); - if (!b) - return NULL; - - if (btree_node_data_alloc(c, b, GFP_KERNEL)) { - kfree(b); - return NULL; - } - - bch2_btree_lock_init(&b->c, 0, GFP_KERNEL); - return b; -} - -static inline bool __btree_node_pinned(struct btree_cache *bc, struct btree *b) -{ - struct bbpos pos = BBPOS(b->c.btree_id, b->key.k.p); - - u64 mask = bc->pinned_nodes_mask[!!b->c.level]; - - return ((mask & BIT_ULL(b->c.btree_id)) && - bbpos_cmp(bc->pinned_nodes_start, pos) < 0 && - bbpos_cmp(bc->pinned_nodes_end, pos) >= 0); -} - -void bch2_node_pin(struct bch_fs *c, struct btree *b) -{ - struct btree_cache *bc = &c->btree_cache; - - mutex_lock(&bc->lock); - if (b != btree_node_root(c, b) && !btree_node_pinned(b)) { - set_btree_node_pinned(b); - list_move(&b->list, &bc->live[1].list); - bc->live[0].nr--; - bc->live[1].nr++; - } - mutex_unlock(&bc->lock); -} - -void bch2_btree_cache_unpin(struct bch_fs *c) -{ - struct btree_cache *bc = &c->btree_cache; - struct btree *b, *n; - - mutex_lock(&bc->lock); - c->btree_cache.pinned_nodes_mask[0] = 0; - c->btree_cache.pinned_nodes_mask[1] = 0; - - list_for_each_entry_safe(b, n, &bc->live[1].list, list) { - clear_btree_node_pinned(b); - list_move(&b->list, &bc->live[0].list); - bc->live[0].nr++; - bc->live[1].nr--; - } - - mutex_unlock(&bc->lock); -} - -/* Btree in memory cache - hash table */ - -void __bch2_btree_node_hash_remove(struct btree_cache *bc, struct btree *b) -{ - lockdep_assert_held(&bc->lock); - - int ret = rhashtable_remove_fast(&bc->table, &b->hash, bch_btree_cache_params); - BUG_ON(ret); - - /* Cause future lookups for this node to fail: */ - b->hash_val = 0; - - if (b->c.btree_id < BTREE_ID_NR) - --bc->nr_by_btree[b->c.btree_id]; - --bc->live[btree_node_pinned(b)].nr; - list_del_init(&b->list); -} - -void bch2_btree_node_hash_remove(struct btree_cache *bc, struct btree *b) -{ - __bch2_btree_node_hash_remove(bc, b); - __bch2_btree_node_to_freelist(bc, b); -} - -int __bch2_btree_node_hash_insert(struct btree_cache *bc, struct btree *b) -{ - BUG_ON(!list_empty(&b->list)); - BUG_ON(b->hash_val); - - b->hash_val = btree_ptr_hash_val(&b->key); - int ret = rhashtable_lookup_insert_fast(&bc->table, &b->hash, - bch_btree_cache_params); - if (ret) - return ret; - - if (b->c.btree_id < BTREE_ID_NR) - bc->nr_by_btree[b->c.btree_id]++; - - bool p = __btree_node_pinned(bc, b); - mod_bit(BTREE_NODE_pinned, &b->flags, p); - - list_add_tail(&b->list, &bc->live[p].list); - bc->live[p].nr++; - return 0; -} - -int bch2_btree_node_hash_insert(struct btree_cache *bc, struct btree *b, - unsigned level, enum btree_id id) -{ - b->c.level = level; - b->c.btree_id = id; - - mutex_lock(&bc->lock); - int ret = __bch2_btree_node_hash_insert(bc, b); - mutex_unlock(&bc->lock); - - return ret; -} - -void bch2_btree_node_update_key_early(struct btree_trans *trans, - enum btree_id btree, unsigned level, - struct bkey_s_c old, struct bkey_i *new) -{ - struct bch_fs *c = trans->c; - struct btree *b; - struct bkey_buf tmp; - int ret; - - bch2_bkey_buf_init(&tmp); - bch2_bkey_buf_reassemble(&tmp, c, old); - - b = bch2_btree_node_get_noiter(trans, tmp.k, btree, level, true); - if (!IS_ERR_OR_NULL(b)) { - mutex_lock(&c->btree_cache.lock); - - __bch2_btree_node_hash_remove(&c->btree_cache, b); - - bkey_copy(&b->key, new); - ret = __bch2_btree_node_hash_insert(&c->btree_cache, b); - BUG_ON(ret); - - mutex_unlock(&c->btree_cache.lock); - six_unlock_read(&b->c.lock); - } - - bch2_bkey_buf_exit(&tmp, c); -} - -__flatten -static inline struct btree *btree_cache_find(struct btree_cache *bc, - const struct bkey_i *k) -{ - u64 v = btree_ptr_hash_val(k); - - return rhashtable_lookup_fast(&bc->table, &v, bch_btree_cache_params); -} - -static int __btree_node_reclaim_checks(struct bch_fs *c, struct btree *b, - bool flush, bool locked) -{ - struct btree_cache *bc = &c->btree_cache; - - lockdep_assert_held(&bc->lock); - - if (btree_node_noevict(b)) { - bc->not_freed[BCH_BTREE_CACHE_NOT_FREED_noevict]++; - return bch_err_throw(c, ENOMEM_btree_node_reclaim); - } - if (btree_node_write_blocked(b)) { - bc->not_freed[BCH_BTREE_CACHE_NOT_FREED_write_blocked]++; - return bch_err_throw(c, ENOMEM_btree_node_reclaim); - } - if (btree_node_will_make_reachable(b)) { - bc->not_freed[BCH_BTREE_CACHE_NOT_FREED_will_make_reachable]++; - return bch_err_throw(c, ENOMEM_btree_node_reclaim); - } - - if (btree_node_dirty(b)) { - if (!flush) { - bc->not_freed[BCH_BTREE_CACHE_NOT_FREED_dirty]++; - return bch_err_throw(c, ENOMEM_btree_node_reclaim); - } - - if (locked) { - /* - * Using the underscore version because we don't want to compact - * bsets after the write, since this node is about to be evicted - * - unless btree verify mode is enabled, since it runs out of - * the post write cleanup: - */ - if (static_branch_unlikely(&bch2_verify_btree_ondisk)) - bch2_btree_node_write(c, b, SIX_LOCK_intent, - BTREE_WRITE_cache_reclaim); - else - __bch2_btree_node_write(c, b, - BTREE_WRITE_cache_reclaim); - } - } - - if (b->flags & ((1U << BTREE_NODE_read_in_flight)| - (1U << BTREE_NODE_write_in_flight))) { - if (!flush) { - if (btree_node_read_in_flight(b)) - bc->not_freed[BCH_BTREE_CACHE_NOT_FREED_read_in_flight]++; - else if (btree_node_write_in_flight(b)) - bc->not_freed[BCH_BTREE_CACHE_NOT_FREED_write_in_flight]++; - return bch_err_throw(c, ENOMEM_btree_node_reclaim); - } - - if (locked) - return -EINTR; - - /* XXX: waiting on IO with btree cache lock held */ - bch2_btree_node_wait_on_read(b); - bch2_btree_node_wait_on_write(b); - } - - return 0; -} - -/* - * this version is for btree nodes that have already been freed (we're not - * reaping a real btree node) - */ -static int __btree_node_reclaim(struct bch_fs *c, struct btree *b, bool flush) -{ - struct btree_cache *bc = &c->btree_cache; - int ret = 0; - - lockdep_assert_held(&bc->lock); -retry_unlocked: - ret = __btree_node_reclaim_checks(c, b, flush, false); - if (ret) - return ret; - - if (!six_trylock_intent(&b->c.lock)) { - bc->not_freed[BCH_BTREE_CACHE_NOT_FREED_lock_intent]++; - return bch_err_throw(c, ENOMEM_btree_node_reclaim); - } - - if (!six_trylock_write(&b->c.lock)) { - bc->not_freed[BCH_BTREE_CACHE_NOT_FREED_lock_write]++; - six_unlock_intent(&b->c.lock); - return bch_err_throw(c, ENOMEM_btree_node_reclaim); - } - - /* recheck under lock */ - ret = __btree_node_reclaim_checks(c, b, flush, true); - if (ret) { - six_unlock_write(&b->c.lock); - six_unlock_intent(&b->c.lock); - if (ret == -EINTR) - goto retry_unlocked; - return ret; - } - - if (b->hash_val && !ret) - trace_and_count(c, btree_cache_reap, c, b); - return 0; -} - -static int btree_node_reclaim(struct bch_fs *c, struct btree *b) -{ - return __btree_node_reclaim(c, b, false); -} - -static int btree_node_write_and_reclaim(struct bch_fs *c, struct btree *b) -{ - return __btree_node_reclaim(c, b, true); -} - -static unsigned long bch2_btree_cache_scan(struct shrinker *shrink, - struct shrink_control *sc) -{ - struct btree_cache_list *list = shrink->private_data; - struct btree_cache *bc = container_of(list, struct btree_cache, live[list->idx]); - struct bch_fs *c = container_of(bc, struct bch_fs, btree_cache); - struct btree *b, *t; - unsigned long nr = sc->nr_to_scan; - unsigned long can_free = 0; - unsigned long freed = 0; - unsigned long touched = 0; - unsigned i, flags; - unsigned long ret = SHRINK_STOP; - bool trigger_writes = atomic_long_read(&bc->nr_dirty) + nr >= list->nr * 3 / 4; - - if (static_branch_unlikely(&bch2_btree_shrinker_disabled)) - return SHRINK_STOP; - - mutex_lock(&bc->lock); - flags = memalloc_nofs_save(); - - /* - * It's _really_ critical that we don't free too many btree nodes - we - * have to always leave ourselves a reserve. The reserve is how we - * guarantee that allocating memory for a new btree node can always - * succeed, so that inserting keys into the btree can always succeed and - * IO can always make forward progress: - */ - can_free = btree_cache_can_free(list); - if (nr > can_free) { - bc->not_freed[BCH_BTREE_CACHE_NOT_FREED_cache_reserve] += nr - can_free; - nr = can_free; - } - - i = 0; - list_for_each_entry_safe(b, t, &bc->freeable, list) { - /* - * Leave a few nodes on the freeable list, so that a btree split - * won't have to hit the system allocator: - */ - if (++i <= 3) - continue; - - touched++; - - if (touched >= nr) - goto out; - - if (!btree_node_reclaim(c, b)) { - btree_node_data_free(bc, b); - six_unlock_write(&b->c.lock); - six_unlock_intent(&b->c.lock); - freed++; - bc->nr_freed++; - } - } -restart: - list_for_each_entry_safe(b, t, &list->list, list) { - touched++; - - if (btree_node_accessed(b)) { - clear_btree_node_accessed(b); - bc->not_freed[BCH_BTREE_CACHE_NOT_FREED_access_bit]++; - --touched;; - } else if (!btree_node_reclaim(c, b)) { - __bch2_btree_node_hash_remove(bc, b); - __btree_node_data_free(b); - btree_node_to_freedlist(bc, b); - - freed++; - bc->nr_freed++; - - six_unlock_write(&b->c.lock); - six_unlock_intent(&b->c.lock); - - if (freed == nr) - goto out_rotate; - } else if (trigger_writes && - btree_node_dirty(b) && - !btree_node_will_make_reachable(b) && - !btree_node_write_blocked(b) && - six_trylock_read(&b->c.lock)) { - list_move(&list->list, &b->list); - mutex_unlock(&bc->lock); - __bch2_btree_node_write(c, b, BTREE_WRITE_cache_reclaim); - six_unlock_read(&b->c.lock); - if (touched >= nr) - goto out_nounlock; - mutex_lock(&bc->lock); - goto restart; - } - - if (touched >= nr) - break; - } -out_rotate: - if (&t->list != &list->list) - list_move_tail(&list->list, &t->list); -out: - mutex_unlock(&bc->lock); -out_nounlock: - ret = freed; - memalloc_nofs_restore(flags); - trace_and_count(c, btree_cache_scan, sc->nr_to_scan, can_free, ret); - return ret; -} - -static unsigned long bch2_btree_cache_count(struct shrinker *shrink, - struct shrink_control *sc) -{ - struct btree_cache_list *list = shrink->private_data; - - if (static_branch_unlikely(&bch2_btree_shrinker_disabled)) - return 0; - - return btree_cache_can_free(list); -} - -void bch2_fs_btree_cache_exit(struct bch_fs *c) -{ - struct btree_cache *bc = &c->btree_cache; - struct btree *b, *t; - unsigned long flags; - - shrinker_free(bc->live[1].shrink); - shrinker_free(bc->live[0].shrink); - - /* vfree() can allocate memory: */ - flags = memalloc_nofs_save(); - mutex_lock(&bc->lock); - - if (c->verify_data) - list_move(&c->verify_data->list, &bc->live[0].list); - - kvfree(c->verify_ondisk); - - for (unsigned i = 0; i < btree_id_nr_alive(c); i++) { - struct btree_root *r = bch2_btree_id_root(c, i); - - if (r->b) - list_add(&r->b->list, &bc->live[0].list); - } - - list_for_each_entry_safe(b, t, &bc->live[1].list, list) - bch2_btree_node_hash_remove(bc, b); - list_for_each_entry_safe(b, t, &bc->live[0].list, list) - bch2_btree_node_hash_remove(bc, b); - - list_for_each_entry_safe(b, t, &bc->freeable, list) { - BUG_ON(btree_node_read_in_flight(b) || - btree_node_write_in_flight(b)); - - btree_node_data_free(bc, b); - cond_resched(); - } - - BUG_ON(!bch2_journal_error(&c->journal) && - atomic_long_read(&c->btree_cache.nr_dirty)); - - list_splice(&bc->freed_pcpu, &bc->freed_nonpcpu); - - list_for_each_entry_safe(b, t, &bc->freed_nonpcpu, list) { - list_del(&b->list); - six_lock_exit(&b->c.lock); - kfree(b); - } - - mutex_unlock(&bc->lock); - memalloc_nofs_restore(flags); - - for (unsigned i = 0; i < ARRAY_SIZE(bc->nr_by_btree); i++) - BUG_ON(bc->nr_by_btree[i]); - BUG_ON(bc->live[0].nr); - BUG_ON(bc->live[1].nr); - BUG_ON(bc->nr_freeable); - - if (bc->table_init_done) - rhashtable_destroy(&bc->table); -} - -int bch2_fs_btree_cache_init(struct bch_fs *c) -{ - struct btree_cache *bc = &c->btree_cache; - struct shrinker *shrink; - unsigned i; - int ret = 0; - - ret = rhashtable_init(&bc->table, &bch_btree_cache_params); - if (ret) - goto err; - - bc->table_init_done = true; - - bch2_recalc_btree_reserve(c); - - for (i = 0; i < bc->nr_reserve; i++) { - struct btree *b = __bch2_btree_node_mem_alloc(c); - if (!b) - goto err; - __bch2_btree_node_to_freelist(bc, b); - } - - list_splice_init(&bc->live[0].list, &bc->freeable); - - mutex_init(&c->verify_lock); - - shrink = shrinker_alloc(0, "%s-btree_cache", c->name); - if (!shrink) - goto err; - bc->live[0].shrink = shrink; - shrink->count_objects = bch2_btree_cache_count; - shrink->scan_objects = bch2_btree_cache_scan; - shrink->seeks = 2; - shrink->private_data = &bc->live[0]; - shrinker_register(shrink); - - shrink = shrinker_alloc(0, "%s-btree_cache-pinned", c->name); - if (!shrink) - goto err; - bc->live[1].shrink = shrink; - shrink->count_objects = bch2_btree_cache_count; - shrink->scan_objects = bch2_btree_cache_scan; - shrink->seeks = 8; - shrink->private_data = &bc->live[1]; - shrinker_register(shrink); - - return 0; -err: - return bch_err_throw(c, ENOMEM_fs_btree_cache_init); -} - -void bch2_fs_btree_cache_init_early(struct btree_cache *bc) -{ - mutex_init(&bc->lock); - for (unsigned i = 0; i < ARRAY_SIZE(bc->live); i++) { - bc->live[i].idx = i; - INIT_LIST_HEAD(&bc->live[i].list); - } - INIT_LIST_HEAD(&bc->freeable); - INIT_LIST_HEAD(&bc->freed_pcpu); - INIT_LIST_HEAD(&bc->freed_nonpcpu); -} - -/* - * We can only have one thread cannibalizing other cached btree nodes at a time, - * or we'll deadlock. We use an open coded mutex to ensure that, which a - * cannibalize_bucket() will take. This means every time we unlock the root of - * the btree, we need to release this lock if we have it held. - */ -void bch2_btree_cache_cannibalize_unlock(struct btree_trans *trans) -{ - struct bch_fs *c = trans->c; - struct btree_cache *bc = &c->btree_cache; - - if (bc->alloc_lock == current) { - trace_and_count(c, btree_cache_cannibalize_unlock, trans); - bc->alloc_lock = NULL; - closure_wake_up(&bc->alloc_wait); - } -} - -int bch2_btree_cache_cannibalize_lock(struct btree_trans *trans, struct closure *cl) -{ - struct bch_fs *c = trans->c; - struct btree_cache *bc = &c->btree_cache; - struct task_struct *old; - - old = NULL; - if (try_cmpxchg(&bc->alloc_lock, &old, current) || old == current) - goto success; - - if (!cl) { - trace_and_count(c, btree_cache_cannibalize_lock_fail, trans); - return bch_err_throw(c, ENOMEM_btree_cache_cannibalize_lock); - } - - closure_wait(&bc->alloc_wait, cl); - - /* Try again, after adding ourselves to waitlist */ - old = NULL; - if (try_cmpxchg(&bc->alloc_lock, &old, current) || old == current) { - /* We raced */ - closure_wake_up(&bc->alloc_wait); - goto success; - } - - trace_and_count(c, btree_cache_cannibalize_lock_fail, trans); - return bch_err_throw(c, btree_cache_cannibalize_lock_blocked); - -success: - trace_and_count(c, btree_cache_cannibalize_lock, trans); - return 0; -} - -static struct btree *btree_node_cannibalize(struct bch_fs *c) -{ - struct btree_cache *bc = &c->btree_cache; - struct btree *b; - - for (unsigned i = 0; i < ARRAY_SIZE(bc->live); i++) - list_for_each_entry_reverse(b, &bc->live[i].list, list) - if (!btree_node_reclaim(c, b)) - return b; - - while (1) { - for (unsigned i = 0; i < ARRAY_SIZE(bc->live); i++) - list_for_each_entry_reverse(b, &bc->live[i].list, list) - if (!btree_node_write_and_reclaim(c, b)) - return b; - - /* - * Rare case: all nodes were intent-locked. - * Just busy-wait. - */ - WARN_ONCE(1, "btree cache cannibalize failed\n"); - cond_resched(); - } -} - -struct btree *bch2_btree_node_mem_alloc(struct btree_trans *trans, bool pcpu_read_locks) -{ - struct bch_fs *c = trans->c; - struct btree_cache *bc = &c->btree_cache; - struct list_head *freed = pcpu_read_locks - ? &bc->freed_pcpu - : &bc->freed_nonpcpu; - struct btree *b, *b2; - u64 start_time = local_clock(); - - mutex_lock(&bc->lock); - - /* - * We never free struct btree itself, just the memory that holds the on - * disk node. Check the freed list before allocating a new one: - */ - list_for_each_entry(b, freed, list) - if (!btree_node_reclaim(c, b)) { - list_del_init(&b->list); - goto got_node; - } - - b = __btree_node_mem_alloc(c, GFP_NOWAIT|__GFP_NOWARN); - if (b) { - bch2_btree_lock_init(&b->c, pcpu_read_locks ? SIX_LOCK_INIT_PCPU : 0, GFP_NOWAIT); - } else { - mutex_unlock(&bc->lock); - bch2_trans_unlock(trans); - b = __btree_node_mem_alloc(c, GFP_KERNEL); - if (!b) - goto err; - bch2_btree_lock_init(&b->c, pcpu_read_locks ? SIX_LOCK_INIT_PCPU : 0, GFP_KERNEL); - mutex_lock(&bc->lock); - } - - BUG_ON(!six_trylock_intent(&b->c.lock)); - BUG_ON(!six_trylock_write(&b->c.lock)); - -got_node: - /* - * btree_free() doesn't free memory; it sticks the node on the end of - * the list. Check if there's any freed nodes there: - */ - list_for_each_entry(b2, &bc->freeable, list) - if (!btree_node_reclaim(c, b2)) { - swap(b->data, b2->data); - swap(b->aux_data, b2->aux_data); - - list_del_init(&b2->list); - --bc->nr_freeable; - btree_node_to_freedlist(bc, b2); - mutex_unlock(&bc->lock); - - six_unlock_write(&b2->c.lock); - six_unlock_intent(&b2->c.lock); - goto got_mem; - } - - mutex_unlock(&bc->lock); - - if (btree_node_data_alloc(c, b, GFP_NOWAIT|__GFP_NOWARN)) { - bch2_trans_unlock(trans); - if (btree_node_data_alloc(c, b, GFP_KERNEL|__GFP_NOWARN)) - goto err; - } - -got_mem: - BUG_ON(!list_empty(&b->list)); - BUG_ON(btree_node_hashed(b)); - BUG_ON(btree_node_dirty(b)); - BUG_ON(btree_node_write_in_flight(b)); -out: - b->flags = 0; - b->written = 0; - b->nsets = 0; - b->sib_u64s[0] = 0; - b->sib_u64s[1] = 0; - b->whiteout_u64s = 0; - bch2_btree_keys_init(b); - - bch2_time_stats_update(&c->times[BCH_TIME_btree_node_mem_alloc], - start_time); - - int ret = bch2_trans_relock(trans); - if (unlikely(ret)) { - bch2_btree_node_to_freelist(c, b); - return ERR_PTR(ret); - } - - return b; -err: - mutex_lock(&bc->lock); - - /* Try to cannibalize another cached btree node: */ - if (bc->alloc_lock == current) { - b2 = btree_node_cannibalize(c); - clear_btree_node_just_written(b2); - __bch2_btree_node_hash_remove(bc, b2); - - if (b) { - swap(b->data, b2->data); - swap(b->aux_data, b2->aux_data); - btree_node_to_freedlist(bc, b2); - six_unlock_write(&b2->c.lock); - six_unlock_intent(&b2->c.lock); - } else { - b = b2; - } - - BUG_ON(!list_empty(&b->list)); - mutex_unlock(&bc->lock); - - trace_and_count(c, btree_cache_cannibalize, trans); - goto out; - } - - mutex_unlock(&bc->lock); - return ERR_PTR(-BCH_ERR_ENOMEM_btree_node_mem_alloc); -} - -/* Slowpath, don't want it inlined into btree_iter_traverse() */ -static noinline struct btree *bch2_btree_node_fill(struct btree_trans *trans, - struct btree_path *path, - const struct bkey_i *k, - enum btree_id btree_id, - unsigned level, - enum six_lock_type lock_type, - bool sync) -{ - struct bch_fs *c = trans->c; - struct btree_cache *bc = &c->btree_cache; - struct btree *b; - - if (unlikely(level >= BTREE_MAX_DEPTH)) { - int ret = bch2_fs_topology_error(c, "attempting to get btree node at level %u, >= max depth %u", - level, BTREE_MAX_DEPTH); - return ERR_PTR(ret); - } - - if (unlikely(!bkey_is_btree_ptr(&k->k))) { - struct printbuf buf = PRINTBUF; - bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(k)); - - int ret = bch2_fs_topology_error(c, "attempting to get btree node with non-btree key %s", buf.buf); - printbuf_exit(&buf); - return ERR_PTR(ret); - } - - if (unlikely(k->k.u64s > BKEY_BTREE_PTR_U64s_MAX)) { - struct printbuf buf = PRINTBUF; - bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(k)); - - int ret = bch2_fs_topology_error(c, "attempting to get btree node with too big key %s", buf.buf); - printbuf_exit(&buf); - return ERR_PTR(ret); - } - - /* - * Parent node must be locked, else we could read in a btree node that's - * been freed: - */ - if (path && !bch2_btree_node_relock(trans, path, level + 1)) { - trace_and_count(c, trans_restart_relock_parent_for_fill, trans, _THIS_IP_, path); - return ERR_PTR(btree_trans_restart(trans, BCH_ERR_transaction_restart_fill_relock)); - } - - b = bch2_btree_node_mem_alloc(trans, level != 0); - - if (bch2_err_matches(PTR_ERR_OR_ZERO(b), ENOMEM)) { - if (!path) - return b; - - trans->memory_allocation_failure = true; - trace_and_count(c, trans_restart_memory_allocation_failure, trans, _THIS_IP_, path); - return ERR_PTR(btree_trans_restart(trans, BCH_ERR_transaction_restart_fill_mem_alloc_fail)); - } - - if (IS_ERR(b)) - return b; - - bkey_copy(&b->key, k); - if (bch2_btree_node_hash_insert(bc, b, level, btree_id)) { - /* raced with another fill: */ - - /* mark as unhashed... */ - b->hash_val = 0; - - mutex_lock(&bc->lock); - __bch2_btree_node_to_freelist(bc, b); - mutex_unlock(&bc->lock); - - six_unlock_write(&b->c.lock); - six_unlock_intent(&b->c.lock); - return NULL; - } - - set_btree_node_read_in_flight(b); - six_unlock_write(&b->c.lock); - - if (path) { - u32 seq = six_lock_seq(&b->c.lock); - - /* Unlock before doing IO: */ - six_unlock_intent(&b->c.lock); - bch2_trans_unlock(trans); - - bch2_btree_node_read(trans, b, sync); - - int ret = bch2_trans_relock(trans); - if (ret) - return ERR_PTR(ret); - - if (!sync) - return NULL; - - if (!six_relock_type(&b->c.lock, lock_type, seq)) - b = NULL; - } else { - bch2_btree_node_read(trans, b, sync); - if (lock_type == SIX_LOCK_read) - six_lock_downgrade(&b->c.lock); - } - - return b; -} - -static noinline void btree_bad_header(struct bch_fs *c, struct btree *b) -{ - struct printbuf buf = PRINTBUF; - - if (c->recovery.pass_done < BCH_RECOVERY_PASS_check_allocations) - return; - - prt_printf(&buf, - "btree node header doesn't match ptr: "); - bch2_btree_id_level_to_text(&buf, b->c.btree_id, b->c.level); - prt_str(&buf, "\nptr: "); - bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(&b->key)); - - prt_str(&buf, "\nheader: "); - bch2_btree_id_level_to_text(&buf, BTREE_NODE_ID(b->data), BTREE_NODE_LEVEL(b->data)); - prt_str(&buf, "\nmin "); - bch2_bpos_to_text(&buf, b->data->min_key); - - prt_printf(&buf, "\nmax "); - bch2_bpos_to_text(&buf, b->data->max_key); - - bch2_fs_topology_error(c, "%s", buf.buf); - - printbuf_exit(&buf); -} - -static inline void btree_check_header(struct bch_fs *c, struct btree *b) -{ - if (b->c.btree_id != BTREE_NODE_ID(b->data) || - b->c.level != BTREE_NODE_LEVEL(b->data) || - !bpos_eq(b->data->max_key, b->key.k.p) || - (b->key.k.type == KEY_TYPE_btree_ptr_v2 && - !bpos_eq(b->data->min_key, - bkey_i_to_btree_ptr_v2(&b->key)->v.min_key))) - btree_bad_header(c, b); -} - -static struct btree *__bch2_btree_node_get(struct btree_trans *trans, struct btree_path *path, - const struct bkey_i *k, unsigned level, - enum six_lock_type lock_type, - unsigned long trace_ip) -{ - struct bch_fs *c = trans->c; - struct btree_cache *bc = &c->btree_cache; - struct btree *b; - bool need_relock = false; - int ret; - - EBUG_ON(level >= BTREE_MAX_DEPTH); -retry: - b = btree_cache_find(bc, k); - if (unlikely(!b)) { - /* - * We must have the parent locked to call bch2_btree_node_fill(), - * else we could read in a btree node from disk that's been - * freed: - */ - b = bch2_btree_node_fill(trans, path, k, path->btree_id, - level, lock_type, true); - need_relock = true; - - /* We raced and found the btree node in the cache */ - if (!b) - goto retry; - - if (IS_ERR(b)) - return b; - } else { - if (btree_node_read_locked(path, level + 1)) - btree_node_unlock(trans, path, level + 1); - - ret = btree_node_lock(trans, path, &b->c, level, lock_type, trace_ip); - if (bch2_err_matches(ret, BCH_ERR_transaction_restart)) - return ERR_PTR(ret); - - BUG_ON(ret); - - if (unlikely(b->hash_val != btree_ptr_hash_val(k) || - b->c.level != level || - race_fault())) { - six_unlock_type(&b->c.lock, lock_type); - if (bch2_btree_node_relock(trans, path, level + 1)) - goto retry; - - trace_and_count(c, trans_restart_btree_node_reused, trans, trace_ip, path); - return ERR_PTR(btree_trans_restart(trans, BCH_ERR_transaction_restart_lock_node_reused)); - } - - /* avoid atomic set bit if it's not needed: */ - if (!btree_node_accessed(b)) - set_btree_node_accessed(b); - } - - if (unlikely(btree_node_read_in_flight(b))) { - u32 seq = six_lock_seq(&b->c.lock); - - six_unlock_type(&b->c.lock, lock_type); - bch2_trans_unlock(trans); - need_relock = true; - - bch2_btree_node_wait_on_read(b); - - ret = bch2_trans_relock(trans); - if (ret) - return ERR_PTR(ret); - - /* - * should_be_locked is not set on this path yet, so we need to - * relock it specifically: - */ - if (!six_relock_type(&b->c.lock, lock_type, seq)) - goto retry; - } - - if (unlikely(need_relock)) { - ret = bch2_trans_relock(trans) ?: - bch2_btree_path_relock_intent(trans, path); - if (ret) { - six_unlock_type(&b->c.lock, lock_type); - return ERR_PTR(ret); - } - } - - prefetch(b->aux_data); - - for_each_bset(b, t) { - void *p = (u64 *) b->aux_data + t->aux_data_offset; - - prefetch(p + L1_CACHE_BYTES * 0); - prefetch(p + L1_CACHE_BYTES * 1); - prefetch(p + L1_CACHE_BYTES * 2); - } - - if (unlikely(btree_node_read_error(b))) { - six_unlock_type(&b->c.lock, lock_type); - return ERR_PTR(-BCH_ERR_btree_node_read_err_cached); - } - - EBUG_ON(b->c.btree_id != path->btree_id); - EBUG_ON(BTREE_NODE_LEVEL(b->data) != level); - btree_check_header(c, b); - - return b; -} - -/** - * bch2_btree_node_get - find a btree node in the cache and lock it, reading it - * in from disk if necessary. - * - * @trans: btree transaction object - * @path: btree_path being traversed - * @k: pointer to btree node (generally KEY_TYPE_btree_ptr_v2) - * @level: level of btree node being looked up (0 == leaf node) - * @lock_type: SIX_LOCK_read or SIX_LOCK_intent - * @trace_ip: ip of caller of btree iterator code (i.e. caller of bch2_btree_iter_peek()) - * - * The btree node will have either a read or a write lock held, depending on - * the @write parameter. - * - * Returns: btree node or ERR_PTR() - */ -struct btree *bch2_btree_node_get(struct btree_trans *trans, struct btree_path *path, - const struct bkey_i *k, unsigned level, - enum six_lock_type lock_type, - unsigned long trace_ip) -{ - struct bch_fs *c = trans->c; - struct btree *b; - int ret; - - EBUG_ON(level >= BTREE_MAX_DEPTH); - - b = btree_node_mem_ptr(k); - - /* - * Check b->hash_val _before_ calling btree_node_lock() - this might not - * be the node we want anymore, and trying to lock the wrong node could - * cause an unneccessary transaction restart: - */ - if (unlikely(!c->opts.btree_node_mem_ptr_optimization || - !b || - b->hash_val != btree_ptr_hash_val(k))) - return __bch2_btree_node_get(trans, path, k, level, lock_type, trace_ip); - - if (btree_node_read_locked(path, level + 1)) - btree_node_unlock(trans, path, level + 1); - - ret = btree_node_lock(trans, path, &b->c, level, lock_type, trace_ip); - if (bch2_err_matches(ret, BCH_ERR_transaction_restart)) - return ERR_PTR(ret); - - BUG_ON(ret); - - if (unlikely(b->hash_val != btree_ptr_hash_val(k) || - b->c.level != level || - race_fault())) { - six_unlock_type(&b->c.lock, lock_type); - if (bch2_btree_node_relock(trans, path, level + 1)) - return __bch2_btree_node_get(trans, path, k, level, lock_type, trace_ip); - - trace_and_count(c, trans_restart_btree_node_reused, trans, trace_ip, path); - return ERR_PTR(btree_trans_restart(trans, BCH_ERR_transaction_restart_lock_node_reused)); - } - - if (unlikely(btree_node_read_in_flight(b))) { - six_unlock_type(&b->c.lock, lock_type); - return __bch2_btree_node_get(trans, path, k, level, lock_type, trace_ip); - } - - prefetch(b->aux_data); - - for_each_bset(b, t) { - void *p = (u64 *) b->aux_data + t->aux_data_offset; - - prefetch(p + L1_CACHE_BYTES * 0); - prefetch(p + L1_CACHE_BYTES * 1); - prefetch(p + L1_CACHE_BYTES * 2); - } - - /* avoid atomic set bit if it's not needed: */ - if (!btree_node_accessed(b)) - set_btree_node_accessed(b); - - if (unlikely(btree_node_read_error(b))) { - six_unlock_type(&b->c.lock, lock_type); - return ERR_PTR(-BCH_ERR_btree_node_read_err_cached); - } - - EBUG_ON(b->c.btree_id != path->btree_id); - EBUG_ON(BTREE_NODE_LEVEL(b->data) != level); - btree_check_header(c, b); - - return b; -} - -struct btree *bch2_btree_node_get_noiter(struct btree_trans *trans, - const struct bkey_i *k, - enum btree_id btree_id, - unsigned level, - bool nofill) -{ - struct bch_fs *c = trans->c; - struct btree_cache *bc = &c->btree_cache; - struct btree *b; - int ret; - - EBUG_ON(level >= BTREE_MAX_DEPTH); - - if (c->opts.btree_node_mem_ptr_optimization) { - b = btree_node_mem_ptr(k); - if (b) - goto lock_node; - } -retry: - b = btree_cache_find(bc, k); - if (unlikely(!b)) { - if (nofill) - goto out; - - b = bch2_btree_node_fill(trans, NULL, k, btree_id, - level, SIX_LOCK_read, true); - - /* We raced and found the btree node in the cache */ - if (!b) - goto retry; - - if (IS_ERR(b) && - !bch2_btree_cache_cannibalize_lock(trans, NULL)) - goto retry; - - if (IS_ERR(b)) - goto out; - } else { -lock_node: - ret = btree_node_lock_nopath(trans, &b->c, SIX_LOCK_read, _THIS_IP_); - if (bch2_err_matches(ret, BCH_ERR_transaction_restart)) - return ERR_PTR(ret); - - BUG_ON(ret); - - if (unlikely(b->hash_val != btree_ptr_hash_val(k) || - b->c.btree_id != btree_id || - b->c.level != level)) { - six_unlock_read(&b->c.lock); - goto retry; - } - - /* avoid atomic set bit if it's not needed: */ - if (!btree_node_accessed(b)) - set_btree_node_accessed(b); - } - - /* XXX: waiting on IO with btree locks held: */ - __bch2_btree_node_wait_on_read(b); - - prefetch(b->aux_data); - - for_each_bset(b, t) { - void *p = (u64 *) b->aux_data + t->aux_data_offset; - - prefetch(p + L1_CACHE_BYTES * 0); - prefetch(p + L1_CACHE_BYTES * 1); - prefetch(p + L1_CACHE_BYTES * 2); - } - - if (unlikely(btree_node_read_error(b))) { - six_unlock_read(&b->c.lock); - b = ERR_PTR(-BCH_ERR_btree_node_read_err_cached); - goto out; - } - - EBUG_ON(b->c.btree_id != btree_id); - EBUG_ON(BTREE_NODE_LEVEL(b->data) != level); - btree_check_header(c, b); -out: - bch2_btree_cache_cannibalize_unlock(trans); - return b; -} - -int bch2_btree_node_prefetch(struct btree_trans *trans, - struct btree_path *path, - const struct bkey_i *k, - enum btree_id btree_id, unsigned level) -{ - struct bch_fs *c = trans->c; - struct btree_cache *bc = &c->btree_cache; - - BUG_ON(path && !btree_node_locked(path, level + 1)); - BUG_ON(level >= BTREE_MAX_DEPTH); - - struct btree *b = btree_cache_find(bc, k); - if (b) - return 0; - - b = bch2_btree_node_fill(trans, path, k, btree_id, - level, SIX_LOCK_read, false); - int ret = PTR_ERR_OR_ZERO(b); - if (ret) - return ret; - if (b) - six_unlock_read(&b->c.lock); - return 0; -} - -void bch2_btree_node_evict(struct btree_trans *trans, const struct bkey_i *k) -{ - struct bch_fs *c = trans->c; - struct btree_cache *bc = &c->btree_cache; - struct btree *b; - - b = btree_cache_find(bc, k); - if (!b) - return; - - BUG_ON(b == btree_node_root(trans->c, b)); -wait_on_io: - /* not allowed to wait on io with btree locks held: */ - - /* XXX we're called from btree_gc which will be holding other btree - * nodes locked - */ - __bch2_btree_node_wait_on_read(b); - __bch2_btree_node_wait_on_write(b); - - btree_node_lock_nopath_nofail(trans, &b->c, SIX_LOCK_intent); - btree_node_lock_nopath_nofail(trans, &b->c, SIX_LOCK_write); - if (unlikely(b->hash_val != btree_ptr_hash_val(k))) - goto out; - - if (btree_node_dirty(b)) { - __bch2_btree_node_write(c, b, BTREE_WRITE_cache_reclaim); - six_unlock_write(&b->c.lock); - six_unlock_intent(&b->c.lock); - goto wait_on_io; - } - - BUG_ON(btree_node_dirty(b)); - - mutex_lock(&bc->lock); - bch2_btree_node_hash_remove(bc, b); - btree_node_data_free(bc, b); - mutex_unlock(&bc->lock); -out: - six_unlock_write(&b->c.lock); - six_unlock_intent(&b->c.lock); -} - -const char *bch2_btree_id_str(enum btree_id btree) -{ - return btree < BTREE_ID_NR ? __bch2_btree_ids[btree] : "(unknown)"; -} - -void bch2_btree_id_to_text(struct printbuf *out, enum btree_id btree) -{ - if (btree < BTREE_ID_NR) - prt_str(out, __bch2_btree_ids[btree]); - else - prt_printf(out, "(unknown btree %u)", btree); -} - -void bch2_btree_id_level_to_text(struct printbuf *out, enum btree_id btree, unsigned level) -{ - prt_str(out, "btree="); - bch2_btree_id_to_text(out, btree); - prt_printf(out, " level=%u", level); -} - -void __bch2_btree_pos_to_text(struct printbuf *out, struct bch_fs *c, - enum btree_id btree, unsigned level, struct bkey_s_c k) -{ - bch2_btree_id_to_text(out, btree); - prt_printf(out, " level %u/", level); - struct btree_root *r = bch2_btree_id_root(c, btree); - if (r) - prt_printf(out, "%u", r->level); - else - prt_printf(out, "(unknown)"); - prt_newline(out); - - bch2_bkey_val_to_text(out, c, k); -} - -void bch2_btree_pos_to_text(struct printbuf *out, struct bch_fs *c, const struct btree *b) -{ - __bch2_btree_pos_to_text(out, c, b->c.btree_id, b->c.level, bkey_i_to_s_c(&b->key)); -} - -void bch2_btree_node_to_text(struct printbuf *out, struct bch_fs *c, const struct btree *b) -{ - struct bset_stats stats; - - memset(&stats, 0, sizeof(stats)); - - bch2_btree_keys_stats(b, &stats); - - prt_printf(out, "l %u ", b->c.level); - bch2_bpos_to_text(out, b->data->min_key); - prt_printf(out, " - "); - bch2_bpos_to_text(out, b->data->max_key); - prt_printf(out, ":\n" - " ptrs: "); - bch2_val_to_text(out, c, bkey_i_to_s_c(&b->key)); - prt_newline(out); - - prt_printf(out, - " format: "); - bch2_bkey_format_to_text(out, &b->format); - - prt_printf(out, - " unpack fn len: %u\n" - " bytes used %zu/%zu (%zu%% full)\n" - " sib u64s: %u, %u (merge threshold %u)\n" - " nr packed keys %u\n" - " nr unpacked keys %u\n" - " floats %zu\n" - " failed unpacked %zu\n", - b->unpack_fn_len, - b->nr.live_u64s * sizeof(u64), - btree_buf_bytes(b) - sizeof(struct btree_node), - b->nr.live_u64s * 100 / btree_max_u64s(c), - b->sib_u64s[0], - b->sib_u64s[1], - c->btree_foreground_merge_threshold, - b->nr.packed_keys, - b->nr.unpacked_keys, - stats.floats, - stats.failed); -} - -static void prt_btree_cache_line(struct printbuf *out, const struct bch_fs *c, - const char *label, size_t nr) -{ - prt_printf(out, "%s\t", label); - prt_human_readable_u64(out, nr * c->opts.btree_node_size); - prt_printf(out, " (%zu)\n", nr); -} - -static const char * const bch2_btree_cache_not_freed_reasons_strs[] = { -#define x(n) #n, - BCH_BTREE_CACHE_NOT_FREED_REASONS() -#undef x - NULL -}; - -void bch2_btree_cache_to_text(struct printbuf *out, const struct btree_cache *bc) -{ - struct bch_fs *c = container_of(bc, struct bch_fs, btree_cache); - - if (!out->nr_tabstops) - printbuf_tabstop_push(out, 32); - - prt_btree_cache_line(out, c, "live:", bc->live[0].nr); - prt_btree_cache_line(out, c, "pinned:", bc->live[1].nr); - prt_btree_cache_line(out, c, "reserve:", bc->nr_reserve); - prt_btree_cache_line(out, c, "freed:", bc->nr_freeable); - prt_btree_cache_line(out, c, "dirty:", atomic_long_read(&bc->nr_dirty)); - prt_printf(out, "cannibalize lock:\t%s\n", bc->alloc_lock ? "held" : "not held"); - prt_newline(out); - - for (unsigned i = 0; i < ARRAY_SIZE(bc->nr_by_btree); i++) { - bch2_btree_id_to_text(out, i); - prt_printf(out, "\t"); - prt_human_readable_u64(out, bc->nr_by_btree[i] * c->opts.btree_node_size); - prt_printf(out, " (%zu)\n", bc->nr_by_btree[i]); - } - - prt_newline(out); - prt_printf(out, "counters since mount:\n"); - prt_printf(out, "freed:\t%zu\n", bc->nr_freed); - prt_printf(out, "not freed:\n"); - - for (unsigned i = 0; i < ARRAY_SIZE(bc->not_freed); i++) - prt_printf(out, " %s\t%llu\n", - bch2_btree_cache_not_freed_reasons_strs[i], bc->not_freed[i]); -} |