Linux 6.9-rc1

[linux-2.6-microblaze.git] / fs / fs-writeback.c

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 3d84fcc..e4f17c5 100644 (file)
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -141,6 +141,31 @@ static void wb_wakeup(struct bdi_writeback *wb)
        spin_unlock_irq(&wb->work_lock);
 }
 
+/*
+ * This function is used when the first inode for this wb is marked dirty. It
+ * wakes-up the corresponding bdi thread which should then take care of the
+ * periodic background write-out of dirty inodes. Since the write-out would
+ * starts only 'dirty_writeback_interval' centisecs from now anyway, we just
+ * set up a timer which wakes the bdi thread up later.
+ *
+ * Note, we wouldn't bother setting up the timer, but this function is on the
+ * fast-path (used by '__mark_inode_dirty()'), so we save few context switches
+ * by delaying the wake-up.
+ *
+ * We have to be careful not to postpone flush work if it is scheduled for
+ * earlier. Thus we use queue_delayed_work().
+ */
+static void wb_wakeup_delayed(struct bdi_writeback *wb)
+{
+       unsigned long timeout;
+
+       timeout = msecs_to_jiffies(dirty_writeback_interval * 10);
+       spin_lock_irq(&wb->work_lock);
+       if (test_bit(WB_registered, &wb->state))
+               queue_delayed_work(bdi_wq, &wb->dwork, timeout);
+       spin_unlock_irq(&wb->work_lock);
+}
+
 static void finish_writeback_work(struct bdi_writeback *wb,
                                  struct wb_writeback_work *work)
 {