Commit fa598b06 authored by David Sterba's avatar David Sterba
Browse files

btrfs: remove recalc_thresholds from free space ops 



After removing the inode number cache that was using the free space
cache code, we can remove at least the recalc_thresholds callback from
the ops. Both code and tests use the same callback function. It's moved
before its first use.

The use_bitmaps callback is still needed by tests to create some
extents/bitmap setup.

Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent f0d1219d

fs/btrfs/free-space-cache.c

+42 −44
Original line number Diff line number Diff line
@@ -597,6 +597,44 @@ static int io_ctl_read_bitmap(struct btrfs_io_ctl *io_ctl, 
	return 0;

}



static void recalculate_thresholds(struct btrfs_free_space_ctl *ctl)

{

	struct btrfs_block_group *block_group = ctl->private;

	u64 max_bytes;

	u64 bitmap_bytes;

	u64 extent_bytes;

	u64 size = block_group->length;

	u64 bytes_per_bg = BITS_PER_BITMAP * ctl->unit;

	u64 max_bitmaps = div64_u64(size + bytes_per_bg - 1, bytes_per_bg);



	max_bitmaps = max_t(u64, max_bitmaps, 1);



	ASSERT(ctl->total_bitmaps <= max_bitmaps);



	/*

	 * We are trying to keep the total amount of memory used per 1GiB of

	 * space to be MAX_CACHE_BYTES_PER_GIG.  However, with a reclamation

	 * mechanism of pulling extents >= FORCE_EXTENT_THRESHOLD out of

	 * bitmaps, we may end up using more memory than this.

	 */

	if (size < SZ_1G)

		max_bytes = MAX_CACHE_BYTES_PER_GIG;

	else

		max_bytes = MAX_CACHE_BYTES_PER_GIG * div_u64(size, SZ_1G);



	bitmap_bytes = ctl->total_bitmaps * ctl->unit;



	/*

	 * we want the extent entry threshold to always be at most 1/2 the max

	 * bytes we can have, or whatever is less than that.

	 */

	extent_bytes = max_bytes - bitmap_bytes;

	extent_bytes = min_t(u64, extent_bytes, max_bytes >> 1);



	ctl->extents_thresh =

		div_u64(extent_bytes, sizeof(struct btrfs_free_space));

}



static int __load_free_space_cache(struct btrfs_root *root, struct inode *inode,

				   struct btrfs_free_space_ctl *ctl,

				   struct btrfs_path *path, u64 offset)
@@ -715,7 +753,7 @@ static int __load_free_space_cache(struct btrfs_root *root, struct inode *inode, 
			spin_lock(&ctl->tree_lock);

			ret = link_free_space(ctl, e);

			ctl->total_bitmaps++;

			ctl->op->recalc_thresholds(ctl);

			recalculate_thresholds(ctl);

			spin_unlock(&ctl->tree_lock);

			if (ret) {

				btrfs_err(fs_info,
@@ -1632,44 +1670,6 @@ static int link_free_space(struct btrfs_free_space_ctl *ctl, 
	return ret;

}



static void recalculate_thresholds(struct btrfs_free_space_ctl *ctl)

{

	struct btrfs_block_group *block_group = ctl->private;

	u64 max_bytes;

	u64 bitmap_bytes;

	u64 extent_bytes;

	u64 size = block_group->length;

	u64 bytes_per_bg = BITS_PER_BITMAP * ctl->unit;

	u64 max_bitmaps = div64_u64(size + bytes_per_bg - 1, bytes_per_bg);



	max_bitmaps = max_t(u64, max_bitmaps, 1);



	ASSERT(ctl->total_bitmaps <= max_bitmaps);



	/*

	 * We are trying to keep the total amount of memory used per 1GiB of

	 * space to be MAX_CACHE_BYTES_PER_GIG.  However, with a reclamation

	 * mechanism of pulling extents >= FORCE_EXTENT_THRESHOLD out of

	 * bitmaps, we may end up using more memory than this.

	 */

	if (size < SZ_1G)

		max_bytes = MAX_CACHE_BYTES_PER_GIG;

	else

		max_bytes = MAX_CACHE_BYTES_PER_GIG * div_u64(size, SZ_1G);



	bitmap_bytes = ctl->total_bitmaps * ctl->unit;



	/*

	 * we want the extent entry threshold to always be at most 1/2 the max

	 * bytes we can have, or whatever is less than that.

	 */

	extent_bytes = max_bytes - bitmap_bytes;

	extent_bytes = min_t(u64, extent_bytes, max_bytes >> 1);



	ctl->extents_thresh =

		div_u64(extent_bytes, sizeof(struct btrfs_free_space));

}



static inline void __bitmap_clear_bits(struct btrfs_free_space_ctl *ctl,

				       struct btrfs_free_space *info,

				       u64 offset, u64 bytes)
@@ -1881,8 +1881,7 @@ static void add_new_bitmap(struct btrfs_free_space_ctl *ctl, 
	INIT_LIST_HEAD(&info->list);

	link_free_space(ctl, info);

	ctl->total_bitmaps++;



	ctl->op->recalc_thresholds(ctl);

	recalculate_thresholds(ctl);

}



static void free_bitmap(struct btrfs_free_space_ctl *ctl,
@@ -1904,7 +1903,7 @@ static void free_bitmap(struct btrfs_free_space_ctl *ctl, 
	kmem_cache_free(btrfs_free_space_bitmap_cachep, bitmap_info->bitmap);

	kmem_cache_free(btrfs_free_space_cachep, bitmap_info);

	ctl->total_bitmaps--;

	ctl->op->recalc_thresholds(ctl);

	recalculate_thresholds(ctl);

}



static noinline int remove_from_bitmap(struct btrfs_free_space_ctl *ctl,
@@ -2071,7 +2070,6 @@ static bool use_bitmap(struct btrfs_free_space_ctl *ctl, 
}



static const struct btrfs_free_space_op free_space_op = {

	.recalc_thresholds	= recalculate_thresholds,

	.use_bitmap		= use_bitmap,

};
@@ -2991,7 +2989,7 @@ u64 btrfs_alloc_from_cluster(struct btrfs_block_group *block_group, 
			kmem_cache_free(btrfs_free_space_bitmap_cachep,

					entry->bitmap);

			ctl->total_bitmaps--;

			ctl->op->recalc_thresholds(ctl);

			recalculate_thresholds(ctl);

		} else if (!btrfs_free_space_trimmed(entry)) {

			ctl->discardable_extents[BTRFS_STAT_CURR]--;

		}

fs/btrfs/free-space-cache.h

+0 −1
Original line number Diff line number Diff line
@@ -60,7 +60,6 @@ struct btrfs_free_space_ctl { 
};



struct btrfs_free_space_op {

	void (*recalc_thresholds)(struct btrfs_free_space_ctl *ctl);

	bool (*use_bitmap)(struct btrfs_free_space_ctl *ctl,

			   struct btrfs_free_space *info);

};

fs/btrfs/tests/free-space-tests.c

+0 −1
Original line number Diff line number Diff line
@@ -399,7 +399,6 @@ test_steal_space_from_bitmap_to_extent(struct btrfs_block_group *cache, 
	u64 offset;

	u64 max_extent_size;

	const struct btrfs_free_space_op test_free_space_ops = {

		.recalc_thresholds = cache->free_space_ctl->op->recalc_thresholds,

		.use_bitmap = test_use_bitmap,

	};

	const struct btrfs_free_space_op *orig_free_space_ops;