md/raid5: move resolving of reconstruct_state earlier in

stripe_handle.

The chunk of code in stripe_handle which responds to a
*_result value in reconstruct_state is really the completion
of some processing that happened outside of handle_stripe
(possibly asynchronously) and so should be one of the first
things done in handle_stripe().

After the next patch it will be important that it happens before
handle_stripe_clean_event(), as that will clear some dev->flags
bit that this code tests.

Signed-off-by: NeilBrown <neilb@suse.de>

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index baea94f..0fb9885 100644 (file)
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -3490,40 +3490,6 @@ static void handle_stripe(struct stripe_head *sh)
                        handle_failed_sync(conf, sh, &s);
        }
 
-       /*
-        * might be able to return some write requests if the parity blocks
-        * are safe, or on a failed drive
-        */
-       pdev = &sh->dev[sh->pd_idx];
-       s.p_failed = (s.failed >= 1 && s.failed_num[0] == sh->pd_idx)
-               || (s.failed >= 2 && s.failed_num[1] == sh->pd_idx);
-       qdev = &sh->dev[sh->qd_idx];
-       s.q_failed = (s.failed >= 1 && s.failed_num[0] == sh->qd_idx)
-               || (s.failed >= 2 && s.failed_num[1] == sh->qd_idx)
-               || conf->level < 6;
-
-       if (s.written &&
-           (s.p_failed || ((test_bit(R5_Insync, &pdev->flags)
-                            && !test_bit(R5_LOCKED, &pdev->flags)
-                            && (test_bit(R5_UPTODATE, &pdev->flags) ||
-                                test_bit(R5_Discard, &pdev->flags))))) &&
-           (s.q_failed || ((test_bit(R5_Insync, &qdev->flags)
-                            && !test_bit(R5_LOCKED, &qdev->flags)
-                            && (test_bit(R5_UPTODATE, &qdev->flags) ||
-                                test_bit(R5_Discard, &qdev->flags))))))
-               handle_stripe_clean_event(conf, sh, disks, &s.return_bi);
-
-       /* Now we might consider reading some blocks, either to check/generate
-        * parity, or to satisfy requests
-        * or to load a block that is being partially written.
-        */
-       if (s.to_read || s.non_overwrite
-           || (conf->level == 6 && s.to_write && s.failed)
-           || (s.syncing && (s.uptodate + s.compute < disks))
-           || s.replacing
-           || s.expanding)
-               handle_stripe_fill(sh, &s, disks);
-
        /* Now we check to see if any write operations have recently
         * completed
         */
@@ -3561,6 +3527,40 @@ static void handle_stripe(struct stripe_head *sh)
                        s.dec_preread_active = 1;
        }
 
+       /*
+        * might be able to return some write requests if the parity blocks
+        * are safe, or on a failed drive
+        */
+       pdev = &sh->dev[sh->pd_idx];
+       s.p_failed = (s.failed >= 1 && s.failed_num[0] == sh->pd_idx)
+               || (s.failed >= 2 && s.failed_num[1] == sh->pd_idx);
+       qdev = &sh->dev[sh->qd_idx];
+       s.q_failed = (s.failed >= 1 && s.failed_num[0] == sh->qd_idx)
+               || (s.failed >= 2 && s.failed_num[1] == sh->qd_idx)
+               || conf->level < 6;
+
+       if (s.written &&
+           (s.p_failed || ((test_bit(R5_Insync, &pdev->flags)
+                            && !test_bit(R5_LOCKED, &pdev->flags)
+                            && (test_bit(R5_UPTODATE, &pdev->flags) ||
+                                test_bit(R5_Discard, &pdev->flags))))) &&
+           (s.q_failed || ((test_bit(R5_Insync, &qdev->flags)
+                            && !test_bit(R5_LOCKED, &qdev->flags)
+                            && (test_bit(R5_UPTODATE, &qdev->flags) ||
+                                test_bit(R5_Discard, &qdev->flags))))))
+               handle_stripe_clean_event(conf, sh, disks, &s.return_bi);
+
+       /* Now we might consider reading some blocks, either to check/generate
+        * parity, or to satisfy requests
+        * or to load a block that is being partially written.
+        */
+       if (s.to_read || s.non_overwrite
+           || (conf->level == 6 && s.to_write && s.failed)
+           || (s.syncing && (s.uptodate + s.compute < disks))
+           || s.replacing
+           || s.expanding)
+               handle_stripe_fill(sh, &s, disks);
+
        /* Now to consider new write requests and what else, if anything
         * should be read.  We do not handle new writes when:
         * 1/ A 'write' operation (copy+xor) is already in flight.