Re: [PATCH] Btrfs: set no_trans_join after trying to expand the transaction

["Jim Schutt" <jaschut@sandia.gov>]

Josef Bacik wrote:
> We can lockup if we try to allow new writers join the transaction and we have
> flushoncommit set or have a pending snapshot.  This is because we set
> no_trans_join and then loop around and try to wait for ordered extents again.
> The problem is the ordered endio stuff needs to join the transaction, which it
> can't do because no_trans_join is set.  So instead wait until after this loop to
> set no_trans_join and then make sure to wait for num_writers == 1 in case
> anybody got started in between us exiting the loop and setting no_trans_join.
> This could easily be reproduced by mounting -o flushoncommit and running xfstest
> 13.  It cannot be reproduced with this patch.  Thanks,

FWIW, this version of the patch works fine for me
as well.

-- Jim

> 
> Reported-by: Jim Schutt <jaschut@sandia.gov>
> Signed-off-by: Josef Bacik <josef@redhat.com>
> ---
>  fs/btrfs/transaction.c |   14 +++++++++++---
>  1 files changed, 11 insertions(+), 3 deletions(-)
>