Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 359dbf19 authored by Mikulas Patocka's avatar Mikulas Patocka Committed by Mike Snitzer
Browse files

dm bufio: use slab cache for dm_buffer structure allocations 



kmalloc padded to the next power of two, using a slab cache avoids this.

Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
parent 03b02939

drivers/md/dm-bufio.c

+19 −9
Original line number Diff line number Diff line
@@ -100,10 +100,10 @@ struct dm_bufio_client { 
	unsigned block_size;

	unsigned char sectors_per_block_bits;

	unsigned char pages_per_block_bits;

	unsigned aux_size;

	void (*alloc_callback)(struct dm_buffer *);

	void (*write_callback)(struct dm_buffer *);



	struct kmem_cache *slab_buffer;

	struct kmem_cache *slab_cache;

	struct dm_io_client *dm_io;
@@ -435,8 +435,7 @@ static void free_buffer_data(struct dm_bufio_client *c, 
 */

static struct dm_buffer *alloc_buffer(struct dm_bufio_client *c, gfp_t gfp_mask)

{

	struct dm_buffer *b = kmalloc(sizeof(struct dm_buffer) + c->aux_size,

				      gfp_mask);

	struct dm_buffer *b = kmem_cache_alloc(c->slab_buffer, gfp_mask);



	if (!b)

		return NULL;
@@ -445,7 +444,7 @@ static struct dm_buffer *alloc_buffer(struct dm_bufio_client *c, gfp_t gfp_mask) 


	b->data = alloc_buffer_data(c, gfp_mask, &b->data_mode);

	if (!b->data) {

		kfree(b);

		kmem_cache_free(c->slab_buffer, b);

		return NULL;

	}
@@ -467,7 +466,7 @@ static void free_buffer(struct dm_buffer *b) 
	adjust_total_allocated(b->data_mode, -(long)c->block_size);



	free_buffer_data(c, b->data, b->data_mode);

	kfree(b);

	kmem_cache_free(c->slab_buffer, b);

}



/*
@@ -1641,6 +1640,7 @@ struct dm_bufio_client *dm_bufio_client_create(struct block_device *bdev, unsign 
	int r;

	struct dm_bufio_client *c;

	unsigned i;

	char slab_name[27];



	BUG_ON(block_size < 1 << SECTOR_SHIFT ||

	       (block_size & (block_size - 1)));
@@ -1658,7 +1658,6 @@ struct dm_bufio_client *dm_bufio_client_create(struct block_device *bdev, unsign 
	c->pages_per_block_bits = (__ffs(block_size) >= PAGE_SHIFT) ?

				  __ffs(block_size) - PAGE_SHIFT : 0;



	c->aux_size = aux_size;

	c->alloc_callback = alloc_callback;

	c->write_callback = write_callback;
@@ -1683,15 +1682,24 @@ struct dm_bufio_client *dm_bufio_client_create(struct block_device *bdev, unsign 
	}



	if (block_size < PAGE_SIZE) {

		char name[26];

		snprintf(name, sizeof name, "dm_bufio_cache-%u", c->block_size);

		c->slab_cache = kmem_cache_create(name, c->block_size, ARCH_KMALLOC_MINALIGN,

		snprintf(slab_name, sizeof slab_name, "dm_bufio_cache-%u", c->block_size);

		c->slab_cache = kmem_cache_create(slab_name, c->block_size, ARCH_KMALLOC_MINALIGN,

						  SLAB_RECLAIM_ACCOUNT, NULL);

		if (!c->slab_cache) {

			r = -ENOMEM;

			goto bad;

		}

	}

	if (aux_size)

		snprintf(slab_name, sizeof slab_name, "dm_bufio_buffer-%u", aux_size);

	else

		snprintf(slab_name, sizeof slab_name, "dm_bufio_buffer");

	c->slab_buffer = kmem_cache_create(slab_name, sizeof(struct dm_buffer) + aux_size,

					   0, SLAB_RECLAIM_ACCOUNT, NULL);

	if (!c->slab_buffer) {

		r = -ENOMEM;

		goto bad;

	}



	while (c->need_reserved_buffers) {

		struct dm_buffer *b = alloc_buffer(c, GFP_KERNEL);
@@ -1727,6 +1735,7 @@ struct dm_bufio_client *dm_bufio_client_create(struct block_device *bdev, unsign 
		free_buffer(b);

	}

	kmem_cache_destroy(c->slab_cache);

	kmem_cache_destroy(c->slab_buffer);

	dm_io_client_destroy(c->dm_io);

bad_dm_io:

	mutex_destroy(&c->lock);
@@ -1774,6 +1783,7 @@ void dm_bufio_client_destroy(struct dm_bufio_client *c) 
		BUG_ON(c->n_buffers[i]);



	kmem_cache_destroy(c->slab_cache);

	kmem_cache_destroy(c->slab_buffer);

	dm_io_client_destroy(c->dm_io);

	mutex_destroy(&c->lock);

	kfree(c);