The parameter 'int n' from bch_bucket_alloc_set() is not cleared defined. From the code comments n is the number of buckets to alloc, but from the code itself 'n' is the maximum cache to iterate. Indeed all the locations where bch_bucket_alloc_set() is called, 'n' is alwasy 1. This patch removes the confused and unnecessary 'int n' from parameter list of bch_bucket_alloc_set(), and explicitly allocates only 1 bucket for its caller. Signed-off-by: Coly Li <colyli@xxxxxxx> Reviewed-by: Hannes Reinecke <hare@xxxxxxx> --- drivers/md/bcache/alloc.c | 35 +++++++++++++++-------------------- drivers/md/bcache/bcache.h | 4 ++-- drivers/md/bcache/btree.c | 2 +- drivers/md/bcache/super.c | 2 +- 4 files changed, 19 insertions(+), 24 deletions(-) diff --git a/drivers/md/bcache/alloc.c b/drivers/md/bcache/alloc.c index 52035a78d836..4493ff57476d 100644 --- a/drivers/md/bcache/alloc.c +++ b/drivers/md/bcache/alloc.c @@ -49,7 +49,7 @@ * * bch_bucket_alloc() allocates a single bucket from a specific cache. * - * bch_bucket_alloc_set() allocates one or more buckets from different caches + * bch_bucket_alloc_set() allocates one bucket from different caches * out of a cache set. * * free_some_buckets() drives all the processes described above. It's called @@ -488,34 +488,29 @@ void bch_bucket_free(struct cache_set *c, struct bkey *k) } int __bch_bucket_alloc_set(struct cache_set *c, unsigned int reserve, - struct bkey *k, int n, bool wait) + struct bkey *k, bool wait) { - int i; + struct cache *ca; + long b; /* No allocation if CACHE_SET_IO_DISABLE bit is set */ if (unlikely(test_bit(CACHE_SET_IO_DISABLE, &c->flags))) return -1; lockdep_assert_held(&c->bucket_lock); - BUG_ON(!n || n > c->caches_loaded || n > MAX_CACHES_PER_SET); bkey_init(k); - /* sort by free space/prio of oldest data in caches */ - - for (i = 0; i < n; i++) { - struct cache *ca = c->cache_by_alloc[i]; - long b = bch_bucket_alloc(ca, reserve, wait); + ca = c->cache_by_alloc[0]; + b = bch_bucket_alloc(ca, reserve, wait); + if (b == -1) + goto err; - if (b == -1) - goto err; + k->ptr[0] = MAKE_PTR(ca->buckets[b].gen, + bucket_to_sector(c, b), + ca->sb.nr_this_dev); - k->ptr[i] = MAKE_PTR(ca->buckets[b].gen, - bucket_to_sector(c, b), - ca->sb.nr_this_dev); - - SET_KEY_PTRS(k, i + 1); - } + SET_KEY_PTRS(k, 1); return 0; err: @@ -525,12 +520,12 @@ int __bch_bucket_alloc_set(struct cache_set *c, unsigned int reserve, } int bch_bucket_alloc_set(struct cache_set *c, unsigned int reserve, - struct bkey *k, int n, bool wait) + struct bkey *k, bool wait) { int ret; mutex_lock(&c->bucket_lock); - ret = __bch_bucket_alloc_set(c, reserve, k, n, wait); + ret = __bch_bucket_alloc_set(c, reserve, k, wait); mutex_unlock(&c->bucket_lock); return ret; } @@ -638,7 +633,7 @@ bool bch_alloc_sectors(struct cache_set *c, spin_unlock(&c->data_bucket_lock); - if (bch_bucket_alloc_set(c, watermark, &alloc.key, 1, wait)) + if (bch_bucket_alloc_set(c, watermark, &alloc.key, wait)) return false; spin_lock(&c->data_bucket_lock); diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h index 4fd03d2496d8..5ff6e9573935 100644 --- a/drivers/md/bcache/bcache.h +++ b/drivers/md/bcache/bcache.h @@ -994,9 +994,9 @@ void bch_bucket_free(struct cache_set *c, struct bkey *k); long bch_bucket_alloc(struct cache *ca, unsigned int reserve, bool wait); int __bch_bucket_alloc_set(struct cache_set *c, unsigned int reserve, - struct bkey *k, int n, bool wait); + struct bkey *k, bool wait); int bch_bucket_alloc_set(struct cache_set *c, unsigned int reserve, - struct bkey *k, int n, bool wait); + struct bkey *k, bool wait); bool bch_alloc_sectors(struct cache_set *c, struct bkey *k, unsigned int sectors, unsigned int write_point, unsigned int write_prio, bool wait); diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c index ae7611fa42bf..e2bd03408e66 100644 --- a/drivers/md/bcache/btree.c +++ b/drivers/md/bcache/btree.c @@ -1091,7 +1091,7 @@ struct btree *__bch_btree_node_alloc(struct cache_set *c, struct btree_op *op, mutex_lock(&c->bucket_lock); retry: - if (__bch_bucket_alloc_set(c, RESERVE_BTREE, &k.key, 1, wait)) + if (__bch_bucket_alloc_set(c, RESERVE_BTREE, &k.key, wait)) goto err; bkey_put(c, &k.key); diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index 61abd6499a11..18358b67d8d6 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -486,7 +486,7 @@ static int __uuid_write(struct cache_set *c) closure_init_stack(&cl); lockdep_assert_held(&bch_register_lock); - if (bch_bucket_alloc_set(c, RESERVE_BTREE, &k.key, 1, true)) + if (bch_bucket_alloc_set(c, RESERVE_BTREE, &k.key, true)) return 1; size = meta_bucket_pages(&c->sb) * PAGE_SECTORS; -- 2.26.2