diff options
| author | Josef Bacik <josef@toxicpanda.com> | 2019-08-22 22:10:54 +0300 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2019-09-09 15:59:17 +0300 |
| commit | ef1317a1b9a347cdc3967a2048046e8fb4db94ba (patch) | |
| tree | cbcfa88ce59b8a387a72cb9e2a9772ffdb4f3da2 | |
| parent | e182163d9cbe86bc0f754068628df55e6dc073d3 (diff) | |
| download | linux-ef1317a1b9a347cdc3967a2048046e8fb4db94ba.tar.xz | |
btrfs: do not allow reservations if we have pending tickets
If we already have tickets on the list we don't want to steal their
reservations. This is a preparation patch for upcoming changes,
technically this shouldn't happen today because of the way we add bytes
to tickets before adding them to the space_info in most cases.
This does not change the FIFO nature of reserve tickets, it simply
allows us to enforce it in a different way. Previously it was enforced
because any new space would be added to the first ticket on the list,
which would result in new reservations getting a reserve ticket. This
replaces that mechanism by simply checking to see if we have outstanding
reserve tickets and skipping straight to adding a ticket for our
reservation.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
| -rw-r--r-- | fs/btrfs/space-info.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c index bea7ae0a9739..918bffb6ba30 100644 --- a/fs/btrfs/space-info.c +++ b/fs/btrfs/space-info.c @@ -993,6 +993,7 @@ static int __reserve_metadata_bytes(struct btrfs_fs_info *fs_info, struct reserve_ticket ticket; u64 used; int ret = 0; + bool pending_tickets; ASSERT(orig_bytes); ASSERT(!current->journal_info || flush != BTRFS_RESERVE_FLUSH_ALL); @@ -1000,14 +1001,17 @@ static int __reserve_metadata_bytes(struct btrfs_fs_info *fs_info, spin_lock(&space_info->lock); ret = -ENOSPC; used = btrfs_space_info_used(space_info, true); + pending_tickets = !list_empty(&space_info->tickets) || + !list_empty(&space_info->priority_tickets); /* * Carry on if we have enough space (short-circuit) OR call * can_overcommit() to ensure we can overcommit to continue. */ - if ((used + orig_bytes <= space_info->total_bytes) || - can_overcommit(fs_info, space_info, orig_bytes, flush, - system_chunk)) { + if (!pending_tickets && + ((used + orig_bytes <= space_info->total_bytes) || + can_overcommit(fs_info, space_info, orig_bytes, flush, + system_chunk))) { btrfs_space_info_update_bytes_may_use(fs_info, space_info, orig_bytes); trace_btrfs_space_reservation(fs_info, "space_info", |