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authorJosef Bacik <josef@toxicpanda.com>2019-06-19 15:11:58 -0400
committerDavid Sterba <dsterba@suse.com>2019-07-04 17:26:17 +0200
commit6ef03debdb3d82d7deec65f96e143b9adcfb2cd4 (patch)
treebcd0cfcb7a8db3e063e78324edd78e69bdf8c88c /fs/btrfs/delayed-ref.c
parent9978059be8a1afd68bc0f7ab4c1883633ddd0312 (diff)
btrfs: migrate the delayed refs rsv code
These belong with the delayed refs related code, not in extent-tree.c. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs/delayed-ref.c')
-rw-r--r--fs/btrfs/delayed-ref.c174
1 files changed, 174 insertions, 0 deletions
diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c
index a94fae897b3f..9a91d1eb0af4 100644
--- a/fs/btrfs/delayed-ref.c
+++ b/fs/btrfs/delayed-ref.c
@@ -10,6 +10,7 @@
#include "delayed-ref.h"
#include "transaction.h"
#include "qgroup.h"
+#include "space-info.h"
struct kmem_cache *btrfs_delayed_ref_head_cachep;
struct kmem_cache *btrfs_delayed_tree_ref_cachep;
@@ -24,6 +25,179 @@ struct kmem_cache *btrfs_delayed_extent_op_cachep;
* of hammering updates on the extent allocation tree.
*/
+bool btrfs_check_space_for_delayed_refs(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv;
+ struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
+ bool ret = false;
+ u64 reserved;
+
+ spin_lock(&global_rsv->lock);
+ reserved = global_rsv->reserved;
+ spin_unlock(&global_rsv->lock);
+
+ /*
+ * Since the global reserve is just kind of magic we don't really want
+ * to rely on it to save our bacon, so if our size is more than the
+ * delayed_refs_rsv and the global rsv then it's time to think about
+ * bailing.
+ */
+ spin_lock(&delayed_refs_rsv->lock);
+ reserved += delayed_refs_rsv->reserved;
+ if (delayed_refs_rsv->size >= reserved)
+ ret = true;
+ spin_unlock(&delayed_refs_rsv->lock);
+ return ret;
+}
+
+int btrfs_should_throttle_delayed_refs(struct btrfs_trans_handle *trans)
+{
+ u64 num_entries =
+ atomic_read(&trans->transaction->delayed_refs.num_entries);
+ u64 avg_runtime;
+ u64 val;
+
+ smp_mb();
+ avg_runtime = trans->fs_info->avg_delayed_ref_runtime;
+ val = num_entries * avg_runtime;
+ if (val >= NSEC_PER_SEC)
+ return 1;
+ if (val >= NSEC_PER_SEC / 2)
+ return 2;
+
+ return btrfs_check_space_for_delayed_refs(trans->fs_info);
+}
+
+/**
+ * btrfs_delayed_refs_rsv_release - release a ref head's reservation.
+ * @fs_info - the fs_info for our fs.
+ * @nr - the number of items to drop.
+ *
+ * This drops the delayed ref head's count from the delayed refs rsv and frees
+ * any excess reservation we had.
+ */
+void btrfs_delayed_refs_rsv_release(struct btrfs_fs_info *fs_info, int nr)
+{
+ struct btrfs_block_rsv *block_rsv = &fs_info->delayed_refs_rsv;
+ u64 num_bytes = btrfs_calc_trans_metadata_size(fs_info, nr);
+ u64 released = 0;
+
+ released = __btrfs_block_rsv_release(fs_info, block_rsv, num_bytes,
+ NULL);
+ if (released)
+ trace_btrfs_space_reservation(fs_info, "delayed_refs_rsv",
+ 0, released, 0);
+}
+
+/*
+ * btrfs_update_delayed_refs_rsv - adjust the size of the delayed refs rsv
+ * @trans - the trans that may have generated delayed refs
+ *
+ * This is to be called anytime we may have adjusted trans->delayed_ref_updates,
+ * it'll calculate the additional size and add it to the delayed_refs_rsv.
+ */
+void btrfs_update_delayed_refs_rsv(struct btrfs_trans_handle *trans)
+{
+ struct btrfs_fs_info *fs_info = trans->fs_info;
+ struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_refs_rsv;
+ u64 num_bytes;
+
+ if (!trans->delayed_ref_updates)
+ return;
+
+ num_bytes = btrfs_calc_trans_metadata_size(fs_info,
+ trans->delayed_ref_updates);
+ spin_lock(&delayed_rsv->lock);
+ delayed_rsv->size += num_bytes;
+ delayed_rsv->full = 0;
+ spin_unlock(&delayed_rsv->lock);
+ trans->delayed_ref_updates = 0;
+}
+
+/**
+ * btrfs_migrate_to_delayed_refs_rsv - transfer bytes to our delayed refs rsv.
+ * @fs_info - the fs info for our fs.
+ * @src - the source block rsv to transfer from.
+ * @num_bytes - the number of bytes to transfer.
+ *
+ * This transfers up to the num_bytes amount from the src rsv to the
+ * delayed_refs_rsv. Any extra bytes are returned to the space info.
+ */
+void btrfs_migrate_to_delayed_refs_rsv(struct btrfs_fs_info *fs_info,
+ struct btrfs_block_rsv *src,
+ u64 num_bytes)
+{
+ struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv;
+ u64 to_free = 0;
+
+ spin_lock(&src->lock);
+ src->reserved -= num_bytes;
+ src->size -= num_bytes;
+ spin_unlock(&src->lock);
+
+ spin_lock(&delayed_refs_rsv->lock);
+ if (delayed_refs_rsv->size > delayed_refs_rsv->reserved) {
+ u64 delta = delayed_refs_rsv->size -
+ delayed_refs_rsv->reserved;
+ if (num_bytes > delta) {
+ to_free = num_bytes - delta;
+ num_bytes = delta;
+ }
+ } else {
+ to_free = num_bytes;
+ num_bytes = 0;
+ }
+
+ if (num_bytes)
+ delayed_refs_rsv->reserved += num_bytes;
+ if (delayed_refs_rsv->reserved >= delayed_refs_rsv->size)
+ delayed_refs_rsv->full = 1;
+ spin_unlock(&delayed_refs_rsv->lock);
+
+ if (num_bytes)
+ trace_btrfs_space_reservation(fs_info, "delayed_refs_rsv",
+ 0, num_bytes, 1);
+ if (to_free)
+ btrfs_space_info_add_old_bytes(fs_info,
+ delayed_refs_rsv->space_info, to_free);
+}
+
+/**
+ * btrfs_delayed_refs_rsv_refill - refill based on our delayed refs usage.
+ * @fs_info - the fs_info for our fs.
+ * @flush - control how we can flush for this reservation.
+ *
+ * This will refill the delayed block_rsv up to 1 items size worth of space and
+ * will return -ENOSPC if we can't make the reservation.
+ */
+int btrfs_delayed_refs_rsv_refill(struct btrfs_fs_info *fs_info,
+ enum btrfs_reserve_flush_enum flush)
+{
+ struct btrfs_block_rsv *block_rsv = &fs_info->delayed_refs_rsv;
+ u64 limit = btrfs_calc_trans_metadata_size(fs_info, 1);
+ u64 num_bytes = 0;
+ int ret = -ENOSPC;
+
+ spin_lock(&block_rsv->lock);
+ if (block_rsv->reserved < block_rsv->size) {
+ num_bytes = block_rsv->size - block_rsv->reserved;
+ num_bytes = min(num_bytes, limit);
+ }
+ spin_unlock(&block_rsv->lock);
+
+ if (!num_bytes)
+ return 0;
+
+ ret = btrfs_reserve_metadata_bytes(fs_info->extent_root, block_rsv,
+ num_bytes, flush);
+ if (ret)
+ return ret;
+ btrfs_block_rsv_add_bytes(block_rsv, num_bytes, 0);
+ trace_btrfs_space_reservation(fs_info, "delayed_refs_rsv",
+ 0, num_bytes, 1);
+ return 0;
+}
+
/*
* compare two delayed tree backrefs with same bytenr and type
*/