Commit 6ae06ff5 authored Jul 01, 2013 by Ashish Sangwan Committed by Theodore Ts'o Jul 01, 2013

ext4: optimize starting extent in ext4_ext_rm_leaf()



Both hole punch and truncate use ext4_ext_rm_leaf() for removing
blocks.  Currently we choose the last extent as the starting
point for removing blocks:

	ex = EXT_LAST_EXTENT(eh);

This is OK for truncate but for hole punch we can optimize the extent
selection as the path is already initialized.  We could use this
information to select proper starting extent.  The code change in this
patch will not affect truncate as for truncate path[depth].p_ext will
always be NULL.

Signed-off-by: Ashish Sangwan <a.sangwan@samsung.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

parent 41a5b913

fs/ext4/extents.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -2504,6 +2504,8 @@ ext4_ext_rm_leaf(handle_t handle, struct inode inode,
		return -EIO;
		}
		/* find where to start removing */
		ex = path[depth].p_ext;
		if (!ex)
		ex = EXT_LAST_EXTENT(eh);

		ex_ee_block = le32_to_cpu(ex->ee_block);

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