On 11.03.20 г. 19:52 ч., Josef Bacik wrote:
> On 3/10/20 5:00 AM, Nikolay Borisov wrote:
>> Instead of iterating all pending tickets on the normal/priority list to
>> sum their total size the cost can be amortized across ticket addition/
>> removal. This turns O(n) + O(m) (where n is the size of the normal list
>> and m of the priority list) into O(1). This will mostly have effect in
>> workloads
>> that experience heavy flushing.
>>
>> Signed-off-by: Nikolay Borisov <nborisov@xxxxxxxx>
>> ---
>> fs/btrfs/space-info.c | 13 ++++++++-----
>> fs/btrfs/space-info.h | 4 ++++
>> 2 files changed, 12 insertions(+), 5 deletions(-)
>>
>> diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c
>> index 9cb511d8cd9d..316a724dc990 100644
>> --- a/fs/btrfs/space-info.c
>> +++ b/fs/btrfs/space-info.c
>> @@ -389,6 +389,8 @@ void btrfs_try_granting_tickets(struct
>> btrfs_fs_info *fs_info,
>> space_info,
>> ticket->bytes);
>> list_del_init(&ticket->list);
>> + ASSERT(space_info->reclaim_size >= ticket->bytes);
>> + space_info->reclaim_size -= ticket->bytes;
>> ticket->bytes = 0;
>> space_info->tickets_id++;
>> wake_up(&ticket->wait);
>> @@ -784,16 +786,15 @@ static inline u64
>> btrfs_calc_reclaim_metadata_size(struct btrfs_fs_info *fs_info,
>> struct btrfs_space_info *space_info)
>> {
>> - struct reserve_ticket *ticket;
>> u64 used;
>> u64 avail;
>> u64 expected;
>> u64 to_reclaim = 0;
>>
>> - list_for_each_entry(ticket, &space_info->tickets, list)
>> - to_reclaim += ticket->bytes;
>> - list_for_each_entry(ticket, &space_info->priority_tickets, list)
>> - to_reclaim += ticket->bytes;
>> + lockdep_assert_held(&space_info->lock);
>> +
>> + if (space_info->reclaim_size)
>> + return space_info->reclaim_size;
>
> This undoes the fix that I put up making sure we include any space we
> can no longer overcommit. Thanks,
Which fix is that?
>
> Josef
