1 files changed, 35 insertions, 3 deletions

diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index 34456476e761..b45109c61fba 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -638,6 +638,11 @@ struct transaction_s
         unsigned long           t_expires;
 
         /*
+         * When this transaction started, in nanoseconds [no locking]
+         */
+        ktime_t                 t_start_time;
+
+        /*
          * How many handles used this transaction? [t_handle_lock]
          */
         int t_handle_count;
@@ -682,6 +687,8 @@ jbd2_time_diff(unsigned long start, unsigned long end)
         return end + (MAX_JIFFY_OFFSET - start);
 }
 
+#define JBD2_NR_BATCH   64
+
 /**
  * struct journal_s - The journal_s type is the concrete type associated with
  *     journal_t.
@@ -826,6 +833,14 @@ struct journal_s
         struct mutex            j_checkpoint_mutex;
 
         /*
+         * List of buffer heads used by the checkpoint routine.  This
+         * was moved from jbd2_log_do_checkpoint() to reduce stack
+         * usage.  Access to this array is controlled by the
+         * j_checkpoint_mutex.  [j_checkpoint_mutex]
+         */
+        struct buffer_head      *j_chkpt_bhs[JBD2_NR_BATCH];
+        
+        /*
          * Journal head: identifies the first unused block in the journal.
          * [j_state_lock]
          */
@@ -939,8 +954,26 @@ struct journal_s
         struct buffer_head      **j_wbuf;
         int                     j_wbufsize;
 
+        /*
+         * this is the pid of hte last person to run a synchronous operation
+         * through the journal
+         */
         pid_t                   j_last_sync_writer;
 
+        /*
+         * the average amount of time in nanoseconds it takes to commit a
+         * transaction to disk. [j_state_lock]
+         */
+        u64                     j_average_commit_time;
+
+        /*
+         * minimum and maximum times that we should wait for
+         * additional filesystem operations to get batched into a
+         * synchronous handle in microseconds
+         */
+        u32                     j_min_batch_time;
+        u32                     j_max_batch_time;
+
         /* This function is called when a transaction is closed */
         void                    (*j_commit_callback)(journal_t *,
                                                      transaction_t *);
@@ -1102,7 +1135,6 @@ extern int	   jbd2_journal_set_features
                    (journal_t *, unsigned long, unsigned long, unsigned long);
 extern void        jbd2_journal_clear_features
                    (journal_t *, unsigned long, unsigned long, unsigned long);
-extern int         jbd2_journal_create     (journal_t *);
 extern int         jbd2_journal_load       (journal_t *journal);
 extern int         jbd2_journal_destroy    (journal_t *);
 extern int         jbd2_journal_recover    (journal_t *journal);
@@ -1177,8 +1209,8 @@ int jbd2_log_wait_commit(journal_t *journal, tid_t tid);
 int jbd2_log_do_checkpoint(journal_t *journal);
 
 void __jbd2_log_wait_for_space(journal_t *journal);
-extern void     __jbd2_journal_drop_transaction(journal_t *, transaction_t *);
-extern int      jbd2_cleanup_journal_tail(journal_t *);
+extern void __jbd2_journal_drop_transaction(journal_t *, transaction_t *);
+extern int jbd2_cleanup_journal_tail(journal_t *);
 
 /* Debugging code only: */