Re: [PATCH 3/6 ]Ext4: journal credits reservation fixes for DIO, fallocate

On Wed, Aug 13, 2008 at 02:23:07PM +0530, Aneesh Kumar K.V wrote:

quoted

 	if (create && !handle) {
 		/* Direct IO write... */
 		if (max_blocks > DIO_MAX_BLOCKS)
 			max_blocks = DIO_MAX_BLOCKS;
-		handle = ext4_journal_start(inode, DIO_CREDITS +
-			      2 * EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb));
+		dio_credits = ext4_data_trans_blocks(inode, max_blocks);
+		handle = ext4_journal_start(inode, dio_credits);

Even in data=journal mode directIO will put the buffer_heads to journal
right ? . So should we use ext4_data_trans_blocks here ?

That should be
Even in data=journal mode directIO will NOT put the buffer_heads to journal

quoted

 		if (IS_ERR(handle)) {
 			ret = PTR_ERR(handle);
 			goto out;

@@ -2222,7 +2214,7 @@ static int ext4_da_writepage(struct page
  * for DIO, writepages, and truncate
  */
 #define EXT4_MAX_WRITEBACK_PAGES      DIO_MAX_BLOCKS
-#define EXT4_MAX_WRITEBACK_CREDITS    DIO_CREDITS
+#define EXT4_MAX_WRITEBACK_CREDITS    25

 static int ext4_da_writepages(struct address_space *mapping,
 				struct writeback_control *wbc)

@@ -4429,7 +4421,8 @@ static int ext4_writeblocks_trans_credit

-aneesh