commit 03bdb5ac58a2144dfe8cfd73347fdb9f57e2e062
author Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Sun Jul 18 10:42:26 2010 +0900
committer Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Fri Jul 23 10:02:16 2010 +0900
tree 1ac37bb7c8020a2cf40ff5d8996d51725b190e8d
parent 4e13e66bee2d792c1aae21797f16c181024834eb

nilfs2: apply read-ahead for nilfs_btree_lookup_contig

This applies read-ahead to nilfs_btree_do_lookup and
nilfs_btree_lookup_contig functions and extends them to read ahead
siblings of level 1 btree nodes that hold data blocks.

At present, the read-ahead is not applied to most btree operations;
only get_block() callback function, which is used during read of
regular files or directories, receives the benefit.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>