btrfs: be more explicit about allowed flush states

For FLUSH_LIMIT flushers we really can only allocate chunks and flush
delayed inode items, everything else is problematic.  I added a bunch of
new states and it lead to weirdness in the FLUSH_LIMIT case because I
forgot about how it worked.  So instead explicitly declare the states
that are ok for flushing with FLUSH_LIMIT and use that for our state
machine.  Then as we add new things that are safe we can just add them
to this list.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Josef Bacik 2018-11-21 14:03:12 -05:00 committed by David Sterba
parent 5df1136363
commit 8a1bbe1d5c

View File

@ -5143,12 +5143,18 @@ void btrfs_init_async_reclaim_work(struct work_struct *work)
INIT_WORK(work, btrfs_async_reclaim_metadata_space);
}
static const enum btrfs_flush_state priority_flush_states[] = {
FLUSH_DELAYED_ITEMS_NR,
FLUSH_DELAYED_ITEMS,
ALLOC_CHUNK,
};
static void priority_reclaim_metadata_space(struct btrfs_fs_info *fs_info,
struct btrfs_space_info *space_info,
struct reserve_ticket *ticket)
{
u64 to_reclaim;
int flush_state = FLUSH_DELAYED_ITEMS_NR;
int flush_state;
spin_lock(&space_info->lock);
to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, space_info,
@ -5159,8 +5165,10 @@ static void priority_reclaim_metadata_space(struct btrfs_fs_info *fs_info,
}
spin_unlock(&space_info->lock);
flush_state = 0;
do {
flush_space(fs_info, space_info, to_reclaim, flush_state);
flush_space(fs_info, space_info, to_reclaim,
priority_flush_states[flush_state]);
flush_state++;
spin_lock(&space_info->lock);
if (ticket->bytes == 0) {
@ -5168,15 +5176,7 @@ static void priority_reclaim_metadata_space(struct btrfs_fs_info *fs_info,
return;
}
spin_unlock(&space_info->lock);
/*
* Priority flushers can't wait on delalloc without
* deadlocking.
*/
if (flush_state == FLUSH_DELALLOC ||
flush_state == FLUSH_DELALLOC_WAIT)
flush_state = ALLOC_CHUNK;
} while (flush_state < COMMIT_TRANS);
} while (flush_state < ARRAY_SIZE(priority_flush_states));
}
static int wait_reserve_ticket(struct btrfs_fs_info *fs_info,