jbd2: Use atomic variables to avoid taking t_handle_lock in jbd2_journal_stop

By using an atomic_t for t_updates and t_outstanding credits, this
should allow us to not need to take transaction t_handle_lock in
jbd2_journal_stop().

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 4 insertions, 4 deletions

diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index 5a72bc75b273..a72ce21de0e1 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -601,13 +601,13 @@ struct transaction_s
          * Number of outstanding updates running on this transaction
          * [t_handle_lock]
          */
-        int                     t_updates;
+        atomic_t                t_updates;
 
         /*
          * Number of buffers reserved for use by all handles in this transaction
          * handle but not yet modified. [t_handle_lock]
          */
-        int                     t_outstanding_credits;
+        atomic_t                t_outstanding_credits;
 
         /*
          * Forward and backward links for the circular list of all transactions
@@ -1258,8 +1258,8 @@ static inline int jbd_space_needed(journal_t *journal)
 {
         int nblocks = journal->j_max_transaction_buffers;
         if (journal->j_committing_transaction)
-                nblocks += journal->j_committing_transaction->
-                                        t_outstanding_credits;
+                nblocks += atomic_read(&journal->j_committing_transaction->
+                                       t_outstanding_credits);
         return nblocks;
 }