Btrfs: avoid taking the trans_mutex in btrfs_end_transaction
I've been working on making our O_DIRECT latency not suck and I noticed we were
taking the trans_mutex in btrfs_end_transaction. So to do this we convert
num_writers and use_count to atomic_t's and just decrement them in
btrfs_end_transaction. Instead of deleting the transaction from the trans list
in put_transaction we do that in btrfs_commit_transaction() since that's the
only time it actually needs to be removed from the list. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
3 files changed