linux.git/fs/nilfs2/bmap.c, branch v2.6.35

nilfs2: trivial coding style fix

2009-12-25T04:01:50+00:00

This is a trivial style fix patch to mend errors/warnings
reported by "checkpatch.pl --file".

Signed-off-by: Jiro SEKIBA 
Signed-off-by: Ryusuke Konishi

nilfs2: move out mark_inode_dirty calls from bmap routines

2009-11-20T01:05:47+00:00

Previously, nilfs_bmap_add_blocks() and nilfs_bmap_sub_blocks() called
mark_inode_dirty() after they changed the number of data blocks.

This moves these calls outside bmap outermost functions like
nilfs_bmap_insert() or nilfs_bmap_truncate().

This will mitigate overhead for truncate or delete operation since
they repeatedly remove set of blocks.  Nearly 10 percent improvement
was observed for removal of a large file:

 # dd if=/dev/zero of=/test/aaa bs=1M count=512
 # time rm /test/aaa

  real  2.968s -> 2.705s

Further optimization may be possible by eliminating these
mark_inode_dirty() uses though I avoid mixing separate changes here.

Signed-off-by: Ryusuke Konishi

nilfs2: stop marking metadata inode dirty within btree operations

2009-11-20T01:05:47+00:00

Since metadata file routines mark the inode dirty after they
successfully changed bmap objects, nilfs_mdt_mark_dirty() calls in
nilfs_bmap_add_blocks() and nilfs_bmap_sub_blocks() are redundant.

This removes these overlapping calls from the bmap routines.

Signed-off-by: Ryusuke Konishi

nilfs2: convert nilfs_bmap_lookup to an inline function

2009-09-14T09:27:16+00:00

The nilfs_bmap_lookup() is now a wrapper function of
nilfs_bmap_lookup_at_level().

This moves the nilfs_bmap_lookup() to a header file converting it to
an inline function and gives an opportunity for optimization.

Signed-off-by: Ryusuke Konishi

nilfs2: allow btree code to directly call dat operations

2009-09-14T09:27:16+00:00

The current btree code is written so that btree functions call dat
operations via wrapper functions in bmap.c when they allocate, free,
or modify virtual block addresses.

This abstraction requires additional function calls and causes
frequent call of nilfs_bmap_get_dat() function since it is used in the
every wrapper function.

This removes the wrapper functions and makes them available from
btree.c and direct.c, which will increase the opportunity of
compiler optimization.

Signed-off-by: Ryusuke Konishi

nilfs2: add update functions of virtual block address to dat

2009-09-14T09:27:15+00:00

This is a preparation for the successive cleanup ("nilfs2: allow btree
to directly call dat operations").

This adds functions bundling a few operations to change an entry of
virtual block address on the dat file.

Signed-off-by: Ryusuke Konishi

nilfs2: fix lockdep warning between regular file and inode file

2009-07-05T01:44:20+00:00

This will fix the following false positive of recursive locking which
lockdep has detected:

=============================================
[ INFO: possible recursive locking detected ]
2.6.30-nilfs #42
---------------------------------------------
nilfs_cleanerd/10607 is trying to acquire lock:
 (&bmap->b_sem){++++-.}, at: [] nilfs_bmap_lookup_at_level+0x1a/0x74 [nilfs2]

but task is already holding lock:
 (&bmap->b_sem){++++-.}, at: [] nilfs_bmap_truncate+0x19/0x6a [nilfs2]
other info that might help us debug this:
2 locks held by nilfs_cleanerd/10607:
 #0:  (&nilfs->ns_segctor_sem){++++.+}, at: [] nilfs_transaction_begin+0xb6/0x10c [nilfs2]
 #1:  (&bmap->b_sem){++++-.}, at: [] nilfs_bmap_truncate+0x19/0x6a [nilfs2]

Signed-off-by: Ryusuke Konishi

nilfs2: support contiguous lookup of blocks

2009-06-10T14:41:12+00:00

Although get_block() callback function can return extent of contiguous
blocks with bh->b_size, nilfs_get_block() function did not support
this feature.

This adds contiguous lookup feature to the block mapping codes of
nilfs, and allows the nilfs_get_blocks() function to return the extent
information by applying the feature.

Signed-off-by: Ryusuke Konishi

nilfs2: remove bmap pointer operations

2009-06-10T14:41:10+00:00

Previously, the bmap codes of nilfs used three types of function
tables.  The abuse of indirect function calls decreased source
readability and suffered many indirect jumps which would confuse
branch prediction of processors.

This eliminates one type of the function tables,
nilfs_bmap_ptr_operations, which was used to dispatch low level
pointer operations of the nilfs bmap.

This adds a new integer variable "b_ptr_type" to nilfs_bmap struct,
and uses the value to select the pointer operations.

Signed-off-by: Ryusuke Konishi

nilfs2: remove useless b_low and b_high fields from nilfs_bmap struct

2009-06-10T14:41:10+00:00

This will cut off 16 bytes from the nilfs_bmap struct which is
embedded in the on-memory inode of nilfs.

The b_high field was never used, and the b_low field stores a constant
value which can be determined by whether the inode uses btree for
block mapping or not.

Signed-off-by: Ryusuke Konishi