1 files changed, 15 insertions, 7 deletions

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 8bc6a8807482..9d3618192009 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -163,6 +163,7 @@ static noinline int run_scheduled_bios(struct btrfs_device *device)
         unsigned long num_sync_run;
         unsigned long limit;
         unsigned long last_waited = 0;
+        int force_reg = 0;
 
         bdi = blk_get_backing_dev_info(device->bdev);
         fs_info = device->dev_root->fs_info;
@@ -176,19 +177,22 @@ static noinline int run_scheduled_bios(struct btrfs_device *device)
 
 loop:
         spin_lock(&device->io_lock);
-        num_run = 0;
 
 loop_lock:
+        num_run = 0;
 
         /* take all the bios off the list at once and process them
          * later on (without the lock held).  But, remember the
          * tail and other pointers so the bios can be properly reinserted
          * into the list if we hit congestion
          */
-        if (device->pending_sync_bios.head)
+        if (!force_reg && device->pending_sync_bios.head) {
                 pending_bios = &device->pending_sync_bios;
-        else
+                force_reg = 1;
+        } else {
                 pending_bios = &device->pending_bios;
+                force_reg = 0;
+        }
 
         pending = pending_bios->head;
         tail = pending_bios->tail;
@@ -228,10 +232,14 @@ loop_lock:
         while (pending) {
 
                 rmb();
-                if (pending_bios != &device->pending_sync_bios &&
-                    device->pending_sync_bios.head &&
-                    num_run > 16) {
-                        cond_resched();
+                /* we want to work on both lists, but do more bios on the
+                 * sync list than the regular list
+                 */
+                if ((num_run > 32 &&
+                    pending_bios != &device->pending_sync_bios &&
+                    device->pending_sync_bios.head) ||
+                   (num_run > 64 && pending_bios == &device->pending_sync_bios &&
+                    device->pending_bios.head)) {
                         spin_lock(&device->io_lock);
                         requeue_list(pending_bios, pending, tail);
                         goto loop_lock;