diff options
| -rw-r--r-- | fs/btrfs/ctree.h | 1 | ||||
| -rw-r--r-- | fs/btrfs/inode.c | 81 | ||||
| -rw-r--r-- | fs/btrfs/space-info.c | 27 |
3 files changed, 62 insertions, 47 deletions
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 4ad4715a7941..b161224b5a0b 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -2536,6 +2536,7 @@ enum btrfs_reserve_flush_enum { * case, use FLUSH LIMIT */ BTRFS_RESERVE_FLUSH_LIMIT, + BTRFS_RESERVE_FLUSH_EVICT, BTRFS_RESERVE_FLUSH_ALL, }; diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 612c25aac15c..c4116bc58827 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -5336,59 +5336,50 @@ static struct btrfs_trans_handle *evict_refill_and_join(struct btrfs_root *root, { struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv; + struct btrfs_trans_handle *trans; u64 delayed_refs_extra = btrfs_calc_trans_metadata_size(fs_info, 1); - int failures = 0; - - for (;;) { - struct btrfs_trans_handle *trans; - int ret; - - ret = btrfs_block_rsv_refill(root, rsv, - rsv->size + delayed_refs_extra, - BTRFS_RESERVE_FLUSH_LIMIT); - - if (ret && ++failures > 2) { - btrfs_warn(fs_info, - "could not allocate space for a delete; will truncate on mount"); - return ERR_PTR(-ENOSPC); - } - - /* - * Evict can generate a large amount of delayed refs without - * having a way to add space back since we exhaust our temporary - * block rsv. We aren't allowed to do FLUSH_ALL in this case - * because we could deadlock with so many things in the flushing - * code, so we have to try and hold some extra space to - * compensate for our delayed ref generation. If we can't get - * that space then we need see if we can steal our minimum from - * the global reserve. We will be ratelimited by the amount of - * space we have for the delayed refs rsv, so we'll end up - * committing and trying again. - */ - trans = btrfs_join_transaction(root); - if (IS_ERR(trans) || !ret) { - if (!IS_ERR(trans)) { - trans->block_rsv = &fs_info->trans_block_rsv; - trans->bytes_reserved = delayed_refs_extra; - btrfs_block_rsv_migrate(rsv, trans->block_rsv, - delayed_refs_extra, 1); - } - return trans; - } + int ret; + /* + * Eviction should be taking place at some place safe because of our + * delayed iputs. However the normal flushing code will run delayed + * iputs, so we cannot use FLUSH_ALL otherwise we'll deadlock. + * + * We reserve the delayed_refs_extra here again because we can't use + * btrfs_start_transaction(root, 0) for the same deadlocky reason as + * above. We reserve our extra bit here because we generate a ton of + * delayed refs activity by truncating. + * + * If we cannot make our reservation we'll attempt to steal from the + * global reserve, because we really want to be able to free up space. + */ + ret = btrfs_block_rsv_refill(root, rsv, rsv->size + delayed_refs_extra, + BTRFS_RESERVE_FLUSH_EVICT); + if (ret) { /* * Try to steal from the global reserve if there is space for * it. */ - if (!btrfs_check_space_for_delayed_refs(fs_info) && - !btrfs_block_rsv_migrate(global_rsv, rsv, rsv->size, 0)) - return trans; + if (btrfs_check_space_for_delayed_refs(fs_info) || + btrfs_block_rsv_migrate(global_rsv, rsv, rsv->size, 0)) { + btrfs_warn(fs_info, + "could not allocate space for delete; will truncate on mount"); + return ERR_PTR(-ENOSPC); + } + delayed_refs_extra = 0; + } - /* If not, commit and try again. */ - ret = btrfs_commit_transaction(trans); - if (ret) - return ERR_PTR(ret); + trans = btrfs_join_transaction(root); + if (IS_ERR(trans)) + return trans; + + if (delayed_refs_extra) { + trans->block_rsv = &fs_info->trans_block_rsv; + trans->bytes_reserved = delayed_refs_extra; + btrfs_block_rsv_migrate(rsv, trans->block_rsv, + delayed_refs_extra, 1); } + return trans; } void btrfs_evict_inode(struct inode *inode) diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c index 37ec31199675..5f8f65599de1 100644 --- a/fs/btrfs/space-info.c +++ b/fs/btrfs/space-info.c @@ -848,6 +848,17 @@ static const enum btrfs_flush_state priority_flush_states[] = { ALLOC_CHUNK, }; +static const enum btrfs_flush_state evict_flush_states[] = { + FLUSH_DELAYED_ITEMS_NR, + FLUSH_DELAYED_ITEMS, + FLUSH_DELAYED_REFS_NR, + FLUSH_DELAYED_REFS, + FLUSH_DELALLOC, + FLUSH_DELALLOC_WAIT, + ALLOC_CHUNK, + COMMIT_TRANS, +}; + static void priority_reclaim_metadata_space(struct btrfs_fs_info *fs_info, struct btrfs_space_info *space_info, struct reserve_ticket *ticket, @@ -922,12 +933,24 @@ static int handle_reserve_ticket(struct btrfs_fs_info *fs_info, u64 reclaim_bytes = 0; int ret; - if (flush == BTRFS_RESERVE_FLUSH_ALL) + switch (flush) { + case BTRFS_RESERVE_FLUSH_ALL: wait_reserve_ticket(fs_info, space_info, ticket); - else + break; + case BTRFS_RESERVE_FLUSH_LIMIT: priority_reclaim_metadata_space(fs_info, space_info, ticket, priority_flush_states, ARRAY_SIZE(priority_flush_states)); + break; + case BTRFS_RESERVE_FLUSH_EVICT: + priority_reclaim_metadata_space(fs_info, space_info, ticket, + evict_flush_states, + ARRAY_SIZE(evict_flush_states)); + break; + default: + ASSERT(0); + break; + } spin_lock(&space_info->lock); ret = ticket->error; |