diff mbox

[V2] Btrfs: replace: cache rbio when rebuild data on missing device

Message ID 1521681611-108404-1-git-send-email-bo.liu@linux.alibaba.com (mailing list archive)
State New, archived
Headers show

Commit Message

Liu Bo March 22, 2018, 1:20 a.m. UTC 
Rebuild on missing device is as same as recover, after it's done, rbio
has data which is consistent with on-disk data, so it can be cached to
avoid further reads.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
---
v2: Add comments to explain why REBUILD needs to be merged.

 fs/btrfs/raid56.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

Comments

David Sterba March 22, 2018, 2:13 p.m. UTC | #1 
On Thu, Mar 22, 2018 at 09:20:11AM +0800, Liu Bo wrote:
> Rebuild on missing device is as same as recover, after it's done, rbio
> has data which is consistent with on-disk data, so it can be cached to
> avoid further reads.
> 
> Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
> Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>

Added to next, thanks.
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diff mbox

Patch

diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c
index fcfc20de2df3..154318249265 100644
--- a/fs/btrfs/raid56.c
+++ b/fs/btrfs/raid56.c
@@ -1987,7 +1987,13 @@  static void __raid_recover_end_io(struct btrfs_raid_bio *rbio)
 	kfree(pointers);
 
 cleanup_io:
-	if (rbio->operation == BTRFS_RBIO_READ_REBUILD) {
+	/*
+	 * Similar to READ_REBUILD, REBUILD_MISSING at this point also has a
+	 * valid rbio which is consistent with ondisk content, thus such a valid
+	 * rbio can be cached to avoid further disk reads.
+	 */
+	if (rbio->operation == BTRFS_RBIO_READ_REBUILD ||
+	    rbio->operation == BTRFS_RBIO_REBUILD_MISSING) {
 		/*
 		 * - In case of two failures, where rbio->failb != -1:
 		 *
@@ -2008,8 +2014,6 @@  static void __raid_recover_end_io(struct btrfs_raid_bio *rbio)
 		else
 			clear_bit(RBIO_CACHE_READY_BIT, &rbio->flags);
 
-		rbio_orig_end_io(rbio, err);
-	} else if (rbio->operation == BTRFS_RBIO_REBUILD_MISSING) {
 		rbio_orig_end_io(rbio, err);
 	} else if (err == BLK_STS_OK) {
 		rbio->faila = -1;