bcachefs: Add a kmem_cache for btree_key_cache objects

We allocate a lot of these, and we're seeing sporading OOMs - this will
help with tracking those down.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This commit is contained in:
Kent Overstreet 2020-11-18 14:09:33 -05:00 committed by Kent Overstreet
parent ed0e24c099
commit 14ba3706b3
3 changed files with 30 additions and 5 deletions

View file

@ -12,6 +12,8 @@
#include <linux/sched/mm.h>
static struct kmem_cache *bch2_key_cache;
static int bch2_btree_key_cache_cmp_fn(struct rhashtable_compare_arg *arg,
const void *obj)
{
@ -104,7 +106,7 @@ bkey_cached_alloc(struct btree_key_cache *c)
return ck;
}
ck = kzalloc(sizeof(*ck), GFP_NOFS);
ck = kmem_cache_alloc(bch2_key_cache, GFP_NOFS|__GFP_ZERO);
if (!ck)
return NULL;
@ -516,7 +518,7 @@ static unsigned long bch2_btree_key_cache_scan(struct shrinker *shrink,
if (poll_state_synchronize_srcu(&c->btree_trans_barrier,
ck->btree_trans_barrier_seq)) {
list_del(&ck->list);
kfree(ck);
kmem_cache_free(bch2_key_cache, ck);
freed++;
}
@ -571,15 +573,18 @@ void bch2_fs_btree_key_cache_exit(struct btree_key_cache *bc)
bch2_journal_preres_put(&c->journal, &ck->res);
kfree(ck->k);
kfree(ck);
list_del(&ck->list);
kmem_cache_free(bch2_key_cache, ck);
bc->nr_keys--;
}
BUG_ON(bc->nr_dirty && !bch2_journal_error(&c->journal));
BUG_ON(bc->nr_keys);
list_for_each_entry_safe(ck, n, &bc->freed, list)
kfree(ck);
list_for_each_entry_safe(ck, n, &bc->freed, list) {
list_del(&ck->list);
kmem_cache_free(bch2_key_cache, ck);
}
mutex_unlock(&bc->lock);
rhashtable_destroy(&bc->table);
@ -627,3 +632,18 @@ void bch2_btree_key_cache_to_text(struct printbuf *out, struct btree_key_cache *
}
mutex_unlock(&c->lock);
}
void bch2_btree_key_cache_exit(void)
{
if (bch2_key_cache)
kmem_cache_destroy(bch2_key_cache);
}
int __init bch2_btree_key_cache_init(void)
{
bch2_key_cache = KMEM_CACHE(bkey_cached, 0);
if (!bch2_key_cache)
return -ENOMEM;
return 0;
}

View file

@ -25,4 +25,7 @@ int bch2_fs_btree_key_cache_init(struct btree_key_cache *);
void bch2_btree_key_cache_to_text(struct printbuf *, struct btree_key_cache *);
void bch2_btree_key_cache_exit(void);
int __init bch2_btree_key_cache_init(void);
#endif /* _BCACHEFS_BTREE_KEY_CACHE_H */

View file

@ -2020,6 +2020,7 @@ static void bcachefs_exit(void)
bch2_debug_exit();
bch2_vfs_exit();
bch2_chardev_exit();
bch2_btree_key_cache_exit();
if (bcachefs_kset)
kset_unregister(bcachefs_kset);
}
@ -2029,6 +2030,7 @@ static int __init bcachefs_init(void)
bch2_bkey_pack_test();
if (!(bcachefs_kset = kset_create_and_add("bcachefs", NULL, fs_kobj)) ||
bch2_btree_key_cache_init() ||
bch2_chardev_init() ||
bch2_vfs_init() ||
bch2_debug_init())