On Thu, May 23, 2019 at 02:51:26PM +0300, Nikolay Borisov wrote: > join_running_log_trans checks btrfs_root::log_root outside of > btrfs_root::log_mutex to avoid contention on the mutex. Turns out this > check is not necessary because the two callers of join_running_log_trans > (both of which deal with removing entries from the tree-log during > unlink) explicitly check whether the respective inode has been logged in > the current transaction. If it hasn't then it won't have any items in > the tree-log and call path will return before calling > join_running_log_trans. If the check passes, however, then it's > guaranteed that btrfs_root::log_root is set because the inode is logged. > > Those guarantees allows us to remove the speculative as well as the > implicity and tricky memory barrier. No functionl changes. > > Signed-off-by: Nikolay Borisov <nborisov@xxxxxxxx> > --- Added to misc-next, thanks.
