nilfs2: apply read-ahead for nilfs_btree_lookup_contig
authorRyusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Sun, 18 Jul 2010 01:42:26 +0000 (10:42 +0900)
committerRyusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Fri, 23 Jul 2010 01:02:16 +0000 (10:02 +0900)
commit03bdb5ac58a2144dfe8cfd73347fdb9f57e2e062
tree1ac37bb7c8020a2cf40ff5d8996d51725b190e8d
parent4e13e66bee2d792c1aae21797f16c181024834eb
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>
fs/nilfs2/btree.c