dm bufio: relax alignment constraint on slab cache (6b5e718c) · Commits · 戴 / test

The I/O buffer doesn't have to be aligned on block size granularity, relax alignment to ARCH_KMALLOC_MINALIGN (required to allow DMA from slab cache memory on some architectures). Also, set SLAB_RECLAIM_ACCOUNT so that the memory allocated from the cache is accounted as reclaimable and doesn't inflate the 'used' entry in the free command. Signed-off-by:

Mikulas Patocka <mpatocka@redhat.com> Signed-off-by:

Mike Snitzer <snitzer@redhat.com>

drivers/md/dm-bufio.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -618,7 +618,6 @@ static void use_inline_bio(struct dm_buffer *b, int rw, sector_t sector,
		unsigned this_step = min((unsigned)(PAGE_SIZE - offset_in_page(ptr)), len);
		if (!bio_add_page(&b->bio, virt_to_page(ptr), this_step,
		offset_in_page(ptr))) {
		BUG_ON(b->c->block_size <= PAGE_SIZE);
		use_dmio(b, rw, sector, n_sectors, offset, end_io);
		return;
		}
		@@ -1686,7 +1685,8 @@ 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, c->block_size, 0, NULL);
		c->slab_cache = kmem_cache_create(name, c->block_size, ARCH_KMALLOC_MINALIGN,
		SLAB_RECLAIM_ACCOUNT, NULL);
		if (!c->slab_cache) {
		r = -ENOMEM;
		goto bad;

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