Commit 41783ef2 authored by Josef Bacik's avatar Josef Bacik Committed by David Sterba
Browse files

btrfs: move and export can_overcommit 



This is the first piece of moving the space reservation code to
space-info.c

Reviewed-by: default avatarNikolay Borisov <nborisov@suse.com>
Signed-off-by: default avatarJosef Bacik <josef@toxicpanda.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 280c2908

fs/btrfs/extent-tree.c

+7 −75
Original line number Diff line number Diff line
@@ -4147,11 +4147,6 @@ static void force_metadata_allocation(struct btrfs_fs_info *info) 
	rcu_read_unlock();

}



static inline u64 calc_global_rsv_need_space(struct btrfs_block_rsv *global)

{

	return (global->size << 1);

}



static int should_alloc_chunk(struct btrfs_fs_info *fs_info,

			      struct btrfs_space_info *sinfo, int force)

{
@@ -4376,69 +4371,6 @@ out: 
	return ret;

}



static int can_overcommit(struct btrfs_fs_info *fs_info,

			  struct btrfs_space_info *space_info, u64 bytes,

			  enum btrfs_reserve_flush_enum flush,

			  bool system_chunk)

{

	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;

	u64 profile;

	u64 space_size;

	u64 avail;

	u64 used;

	int factor;



	/* Don't overcommit when in mixed mode. */

	if (space_info->flags & BTRFS_BLOCK_GROUP_DATA)

		return 0;



	if (system_chunk)

		profile = btrfs_system_alloc_profile(fs_info);

	else

		profile = btrfs_metadata_alloc_profile(fs_info);



	used = btrfs_space_info_used(space_info, false);



	/*

	 * We only want to allow over committing if we have lots of actual space

	 * free, but if we don't have enough space to handle the global reserve

	 * space then we could end up having a real enospc problem when trying

	 * to allocate a chunk or some other such important allocation.

	 */

	spin_lock(&global_rsv->lock);

	space_size = calc_global_rsv_need_space(global_rsv);

	spin_unlock(&global_rsv->lock);

	if (used + space_size >= space_info->total_bytes)

		return 0;



	used += space_info->bytes_may_use;



	avail = atomic64_read(&fs_info->free_chunk_space);



	/*

	 * If we have dup, raid1 or raid10 then only half of the free

	 * space is actually usable.  For raid56, the space info used

	 * doesn't include the parity drive, so we don't have to

	 * change the math

	 */

	factor = btrfs_bg_type_to_factor(profile);

	avail = div_u64(avail, factor);



	/*

	 * If we aren't flushing all things, let us overcommit up to

	 * 1/2th of the space. If we can flush, don't let us overcommit

	 * too much, let it overcommit up to 1/8 of the space.

	 */

	if (flush == BTRFS_RESERVE_FLUSH_ALL)

		avail >>= 3;

	else

		avail >>= 1;



	if (used + bytes < space_info->total_bytes + avail)

		return 1;

	return 0;

}



static void btrfs_writeback_inodes_sb_nr(struct btrfs_fs_info *fs_info,

					 unsigned long nr_pages, int nr_items)

{
@@ -4766,13 +4698,13 @@ btrfs_calc_reclaim_metadata_size(struct btrfs_fs_info *fs_info, 
		return to_reclaim;



	to_reclaim = min_t(u64, num_online_cpus() * SZ_1M, SZ_16M);

	if (can_overcommit(fs_info, space_info, to_reclaim,

	if (btrfs_can_overcommit(fs_info, space_info, to_reclaim,

				 BTRFS_RESERVE_FLUSH_ALL, system_chunk))

		return 0;



	used = btrfs_space_info_used(space_info, true);



	if (can_overcommit(fs_info, space_info, SZ_1M,

	if (btrfs_can_overcommit(fs_info, space_info, SZ_1M,

				 BTRFS_RESERVE_FLUSH_ALL, system_chunk))

		expected = div_factor_fine(space_info->total_bytes, 95);

	else
@@ -5019,7 +4951,7 @@ static int __reserve_metadata_bytes(struct btrfs_fs_info *fs_info, 
		trace_btrfs_space_reservation(fs_info, "space_info",

					      space_info->flags, orig_bytes, 1);

		ret = 0;

	} else if (can_overcommit(fs_info, space_info, orig_bytes, flush,

	} else if (btrfs_can_overcommit(fs_info, space_info, orig_bytes, flush,

					system_chunk)) {

		update_bytes_may_use(fs_info, space_info, orig_bytes);

		trace_btrfs_space_reservation(fs_info, "space_info",
@@ -5331,7 +5263,7 @@ again: 
		 * adding the ticket space would be a double count.

		 */

		if (check_overcommit &&

		    !can_overcommit(fs_info, space_info, 0, flush, false))

		    !btrfs_can_overcommit(fs_info, space_info, 0, flush, false))

			break;

		if (num_bytes >= ticket->bytes) {

			list_del_init(&ticket->list);

fs/btrfs/space-info.c

+68 −0
Original line number Diff line number Diff line
@@ -172,3 +172,71 @@ struct btrfs_space_info *btrfs_find_space_info(struct btrfs_fs_info *info, 
	rcu_read_unlock();

	return NULL;

}



static inline u64 calc_global_rsv_need_space(struct btrfs_block_rsv *global)

{

	return (global->size << 1);

}



int btrfs_can_overcommit(struct btrfs_fs_info *fs_info,

			 struct btrfs_space_info *space_info, u64 bytes,

			 enum btrfs_reserve_flush_enum flush,

			 bool system_chunk)

{

	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;

	u64 profile;

	u64 space_size;

	u64 avail;

	u64 used;

	int factor;



	/* Don't overcommit when in mixed mode. */

	if (space_info->flags & BTRFS_BLOCK_GROUP_DATA)

		return 0;



	if (system_chunk)

		profile = btrfs_system_alloc_profile(fs_info);

	else

		profile = btrfs_metadata_alloc_profile(fs_info);



	used = btrfs_space_info_used(space_info, false);



	/*

	 * We only want to allow over committing if we have lots of actual space

	 * free, but if we don't have enough space to handle the global reserve

	 * space then we could end up having a real enospc problem when trying

	 * to allocate a chunk or some other such important allocation.

	 */

	spin_lock(&global_rsv->lock);

	space_size = calc_global_rsv_need_space(global_rsv);

	spin_unlock(&global_rsv->lock);

	if (used + space_size >= space_info->total_bytes)

		return 0;



	used += space_info->bytes_may_use;



	avail = atomic64_read(&fs_info->free_chunk_space);



	/*

	 * If we have dup, raid1 or raid10 then only half of the free

	 * space is actually usable.  For raid56, the space info used

	 * doesn't include the parity drive, so we don't have to

	 * change the math

	 */

	factor = btrfs_bg_type_to_factor(profile);

	avail = div_u64(avail, factor);



	/*

	 * If we aren't flushing all things, let us overcommit up to

	 * 1/2th of the space. If we can flush, don't let us overcommit

	 * too much, let it overcommit up to 1/8 of the space.

	 */

	if (flush == BTRFS_RESERVE_FLUSH_ALL)

		avail >>= 3;

	else

		avail >>= 1;



	if (used + bytes < space_info->total_bytes + avail)

		return 1;

	return 0;

}

fs/btrfs/space-info.h

+4 −0
Original line number Diff line number Diff line
@@ -91,5 +91,9 @@ struct btrfs_space_info *btrfs_find_space_info(struct btrfs_fs_info *info, 
u64 btrfs_space_info_used(struct btrfs_space_info *s_info,

			  bool may_use_included);

void btrfs_clear_space_info_full(struct btrfs_fs_info *info);

int btrfs_can_overcommit(struct btrfs_fs_info *fs_info,

			 struct btrfs_space_info *space_info, u64 bytes,

			 enum btrfs_reserve_flush_enum flush,

			 bool system_chunk);



#endif /* BTRFS_SPACE_INFO_H */

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