[patch 26/47] md: ensure all blocks are uptodate or locked when syncing

Greg KH
2008-07-22T23:26:58Z

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2.6.25-stable review patch. If anyone has any objections, please let us
know.

------------------
From: Dan Williams <dan.j.williams@intel.com>

commit 7a1fc53c5adb910751a9b212af90302eb4ffb527 upstream

Remove the dubious attempt to prefer 'compute' over 'read'. Not only is it
wrong given commit c337869d (md: do not compute parity unless it is on a failed
drive), but it can trigger a BUG_ON in handle_parity_checks5().

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
drivers/md/raid5.c | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)

--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -1999,12 +1999,7 @@ static int __handle_issuing_new_read_req
*/
s->uptodate++;
return 0; /* uptodate + compute == disks */
- } else if ((s->uptodate < disks - 1) &&
- test_bit(R5_Insync, &dev->flags)) {
- /* Note: we hold off compute operations while checks are
- * in flight, but we still prefer 'compute' over 'read'
- * hence we only read if (uptodate < * disks-1)
- */
+ } else if (test_bit(R5_Insync, &dev->flags)) {
set_bit(R5_LOCKED, &dev->flags);
set_bit(R5_Wantread, &dev->flags);
if (!test_and_set_bit(STRIPE_OP_IO, &sh->ops.pending))

--