Merge 6.4-rc5 into usb-next

[platform/kernel/linux-starfive.git] / fs / ext4 / mballoc.c

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 7b2e36d..20f67a2 100644 (file)
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -2062,7 +2062,7 @@ static void ext4_mb_check_limits(struct ext4_allocation_context *ac,
        if (bex->fe_len < gex->fe_len)
                return;
 
-       if (finish_group)
+       if (finish_group || ac->ac_found > sbi->s_mb_min_to_scan)
                ext4_mb_use_best_found(ac, e4b);
 }
 
@@ -2074,6 +2074,20 @@ static void ext4_mb_check_limits(struct ext4_allocation_context *ac,
  * in the context. Later, the best found extent will be used, if
  * mballoc can't find good enough extent.
  *
+ * The algorithm used is roughly as follows:
+ *
+ * * If free extent found is exactly as big as goal, then
+ *   stop the scan and use it immediately
+ *
+ * * If free extent found is smaller than goal, then keep retrying
+ *   upto a max of sbi->s_mb_max_to_scan times (default 200). After
+ *   that stop scanning and use whatever we have.
+ *
+ * * If free extent found is bigger than goal, then keep retrying
+ *   upto a max of sbi->s_mb_min_to_scan times (default 10) before
+ *   stopping the scan and using the extent.
+ *
+ *
  * FIXME: real allocation policy is to be designed yet!
  */
 static void ext4_mb_measure_extent(struct ext4_allocation_context *ac,