Commit 17e4aed8 authored by Coly Li's avatar Coly Li Committed by Jens Axboe
Browse files

bcache: remove 'int n' from parameter list of bch_bucket_alloc_set() 



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: default avatarColy Li <colyli@suse.de>
Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 84e5d136

drivers/md/bcache/alloc.c

+15 −20
Original line number Diff line number Diff line
@@ -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;



		k->ptr[i] = MAKE_PTR(ca->buckets[b].gen,

	k->ptr[0] = 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 @@ err: 
}



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);

drivers/md/bcache/bcache.h

+2 −2
Original line number Diff line number Diff line
@@ -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);

drivers/md/bcache/btree.c

+1 −1
Original line number Diff line number Diff line
@@ -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);

drivers/md/bcache/super.c

+1 −1
Original line number Diff line number Diff line
@@ -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;

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