1 files changed, 15 insertions, 0 deletions

diff --git a/fs/jbd/commit.c b/fs/jbd/commit.c
index 25719d902c51..3fbffb1ea714 100644
--- a/fs/jbd/commit.c
+++ b/fs/jbd/commit.c
@@ -306,6 +306,8 @@ void journal_commit_transaction(journal_t *journal)
         int flags;
         int err;
         unsigned long blocknr;
+        ktime_t start_time;
+        u64 commit_time;
         char *tagp = NULL;
         journal_header_t *header;
         journal_block_tag_t *tag = NULL;
@@ -418,6 +420,7 @@ void journal_commit_transaction(journal_t *journal)
         commit_transaction->t_state = T_FLUSH;
         journal->j_committing_transaction = commit_transaction;
         journal->j_running_transaction = NULL;
+        start_time = ktime_get();
         commit_transaction->t_log_start = journal->j_head;
         wake_up(&journal->j_wait_transaction_locked);
         spin_unlock(&journal->j_state_lock);
@@ -913,6 +916,18 @@ restart_loop:
         J_ASSERT(commit_transaction == journal->j_committing_transaction);
         journal->j_commit_sequence = commit_transaction->t_tid;
         journal->j_committing_transaction = NULL;
+        commit_time = ktime_to_ns(ktime_sub(ktime_get(), start_time));
+
+        /*
+         * weight the commit time higher than the average time so we don't
+         * react too strongly to vast changes in commit time
+         */
+        if (likely(journal->j_average_commit_time))
+                journal->j_average_commit_time = (commit_time*3 +
+                                journal->j_average_commit_time) / 4;
+        else
+                journal->j_average_commit_time = commit_time;
+
         spin_unlock(&journal->j_state_lock);
 
         if (commit_transaction->t_checkpoint_list == NULL &&