Commit Graph

267 Commits

Author SHA1 Message Date
Haibo Liu
62a1391ddd ext4: remove an unused statement in ext4_mb_get_buddy_page_lock()
In this patch, the statement "poff = block % blocks_per_page"
in ext4_mb_get_buddy_page_lock has no effect.

It will be optimized out by the compiler, but it's better to remove it.

Signed-off-by: Haibo Liu <HaiboLiu6@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-07-09 16:29:28 -04:00
Aditya Kali
1c8457cadc ext4: avoid uneeded calls to ext4_mb_load_buddy() while reading mb_groups
Currently ext4_mb_load_buddy is called for every group, irrespective
of whether the group info is already in memory, while reading
/proc/fs/ext4/<partition>/mb_groups proc file.  For the purpose of
mb_groups proc file, it is unnecessary to load the file group info
from disk if it was loaded in past.  These calls to ext4_mb_load_buddy
make reading the mb_groups proc file expensive.

Also, the locks around ext4_get_group_info are not required.

This patch modifies the code to call ext4_mb_load_buddy only if the
group info had never been loaded into memory in past. It also removes
the mb group locking around ext4_get_group_info call.

Signed-off-by: Aditya Kali <adityakali@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-06-30 19:10:57 -04:00
Salman Qazi
95599968d1 ext4: remove mb_groups before tearing down the buddy_cache
We can't have references held on pages in the s_buddy_cache while we are
trying to truncate its pages and put the inode.  All the pages must be
gone before we reach clear_inode.  This can only be gauranteed if we
can prevent new users from grabbing references to s_buddy_cache's pages.

The original bug can be reproduced and the bug fix can be verified by:

while true; do mount -t ext4 /dev/ram0 /export/hda3/ram0; \
	umount /export/hda3/ram0; done &

while true; do cat /proc/fs/ext4/ram0/mb_groups; done

Signed-off-by: Salman Qazi <sqazi@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
2012-05-31 23:52:14 -04:00
Salman Qazi
02b7831019 ext4: add ext4_mb_unload_buddy in the error path
ext4_free_blocks fails to pair an ext4_mb_load_buddy with a matching
ext4_mb_unload_buddy when it fails a memory allocation.

Signed-off-by: Salman Qazi <sqazi@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
2012-05-31 23:51:27 -04:00
Zheng Liu
400db9d301 ext4: cleanup in ext4_discard_allocated_blocks()
remove 'len' variable in ext4_discard_allocated_blocks() because it is
useless.

Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-05-28 17:53:53 -04:00
Akira Fujita
9d99012ff2 ext4: remove needs_recovery in ext4_mb_init()
needs_recovery in ext4_mb_init() is not used, remove it.

Signed-off-by: Akira Fujita <a-fujita@rs.jp.ne.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-05-28 14:19:25 -04:00
Darrick J. Wong
feb0ab32a5 ext4: make block group checksums use metadata_csum algorithm
metadata_csum supersedes uninit_bg.  Convert the ROCOMPAT uninit_bg
flag check to a helper function that covers both, and make the
checksum calculation algorithm use either crc16 or the metadata_csum
chosen algorithm depending on which flag is set.  Print a warning if
we try to mount a filesystem with both feature flags set.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-04-29 18:45:10 -04:00
Darrick J. Wong
fa77dcfafe ext4: calculate and verify block bitmap checksum
Compute and verify the checksum of the block bitmap; this checksum is
stored in the block group descriptor.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-04-29 18:35:10 -04:00
Lukas Czerner
a7967f055a ext4: always set then trimmed blocks count into len
Currently if the range to trim is too small, for example on 1K fs
the request to trim the first block, then the 'range->len' is not set
reporting wrong number of discarded block to the caller.

Fix this by always setting the 'range->len' before we return. Note that
when there is a failure (-EINVAL) caller can not depend on 'range->len'
being set properly.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-21 21:26:22 -04:00
Lukas Czerner
21e7fd22a5 ext4: fix trimmed block count accunting
Currently when there is not enough free blocks in the block group to
discard (grp->bb_free < minlen) the 'trimmed' is bumped up anyway with
the number of discarded blocks from the previous iteration. Fix this
by bumping up 'trimmed' only if the ext4_trim_all_free() was actually
run.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-21 21:24:22 -04:00
Lukas Czerner
913eed83ed ext4: fix start and len arguments handling in ext4_trim_fs()
The overflow can happen when we are calling get_group_no_and_offset()
which stores the group number in the ext4_grpblk_t type which is
actually int. However when the blocknr is big enough the group number
might be bigger than ext4_grpblk_t resulting in overflow. This will
most likely happen with FITRIM default argument len = ULLONG_MAX.

Fix this by using "end" variable instead of "start+len" as it is easier
to get right and specifically check that the end is not beyond the end
of the file system, so we are sure that the result of
get_group_no_and_offset() will not overflow. Otherwise truncate it to
the size of the file system.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-21 21:22:22 -04:00
Theodore Ts'o
1084f252e3 ext4: remove trailing newlines from ext4_msg() and ext4_error() messages
The functions ext4_msg() and ext4_error() already tack on a trailing
newline, so remove the unnecessary extra newline.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-19 23:13:43 -04:00
Joe Perches
7f6a11e73d ext4: remove redundant "EXT4-fs: " from uses of ext4_msg
ext4_msg adds "EXT4-fs: " to the messsage output.
Remove the redundant bits from uses.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-19 23:09:43 -04:00
Theodore Ts'o
c5e8f3f3bc ext4: remove EXT4_MB_{BITMAP,BUDDY} macros
The EXT4_MB_BITMAP and EXT4_MB_BUDDY macros obfuscate more than they
provide any abstraction.   So remove them.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-02-20 17:54:06 -05:00
Curt Wohlgemuth
1592d2c557 ext4: mark possibly unused variable in ext4_mb_normalize_request()
The 'orig_size' local variable is only used in a call to
mb_debug().  Mark it with '__maybe_unused'.

Signed-off-by: Curt Wohlgemuth <curtw@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-02-20 17:53:03 -05:00
Bobi Jam
18aadd47f8 ext4: expand commit callback and
The per-commit callback was used by mballoc code to manage free space
bitmaps after deleted blocks have been released.  This patch expands
it to support multiple different callbacks, to allow other things to
be done after the commit has been completed.

Signed-off-by: Bobi Jam <bobijam@whamcloud.com>
Signed-off-by: Andreas Dilger <adilger@whamcloud.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-02-20 17:53:02 -05:00
Theodore Ts'o
813e57276f ext4: fix race when setting bitmap_uptodate flag
In ext4_read_{inode,block}_bitmap() we were setting bitmap_uptodate()
before submitting the buffer for read.  The is bad, since we check
bitmap_uptodate() without locking the buffer, and so if another
process is racing with us, it's possible that they will think the
bitmap is uptodate even though the read has not completed yet,
resulting in inodes and blocks potentially getting allocated more than
once if we get really unlucky.

Addresses-Google-Bug: 2828254

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-02-20 17:52:46 -05:00
Yongqiang Yang
60e07cf515 ext4: do not reference pa_inode from group_pa
pa_inode in group_pa is set NULL in ext4_mb_new_group_pa, so
pa_inode should be not referenced.

Reported-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-12-18 15:49:54 -05:00
Robin Dong
0a10da73e1 ext4: fix a wrong comment in __mb_check_buddy()
The comment says the bit should be 0, but the after code assert the
bit to be 1.  This makes people confused, so fix it.

Signed-off-by: Robin Dong <sanbai@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-10-26 08:48:54 -04:00
Robin Dong
b051d8dc4e ext4: remove unused variable in mb_find_extent()
The variable 'ord' in function mb_find_extent() is redundant, so
remove it.

Signed-off-by: Robin Dong <sanbai@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-10-26 05:30:30 -04:00
Robin Dong
66a83cde47 ext4: remove unused variable in ext4_mb_generate_from_pa()
The variable 'count' in function ext4_mb_generate_from_pa() looks
useless, so remove it.

Signed-off-by: Robin Dong <sanbai@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-10-26 05:29:21 -04:00
Robin Dong
ebbe027797 ext4: use stream-alloc when mb_group_prealloc set to zero
The kernel will crash on 

ext4_mb_mark_diskspace_used:
	BUG_ON(ac->ac_b_ex.fe_len <= 0);

after we set /sys/fs/ext4/sda/mb_group_prealloc to zero and create new files in an ext4 filesystem.

The reason is: ac_b_ex.fe_len also set to zero(mb_group_prealloc) in ext4_mb_normalize_group_request
because the ac_flags contains EXT4_MB_HINT_GROUP_ALLOC.

I think when someone set mb_group_prealloc to zero, it means DO NOT USE GROUP PREALLOCATION,
so we should set alloc-strategy to STREAM in this case.

Signed-off-by: Robin Dong <sanbai@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-10-26 05:14:27 -04:00
Dmitry Monakhov
45dc63e7d8 ext4: Allow quota file use root reservation
Quota file is fs's metadata, so it is reasonable  to permit use
root resevation if necessary. This patch fix 265'th xfstest failure

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-10-20 20:07:23 -04:00
Tao Ma
7aa0baeaba ext4: Free resources in ext4_mb_init()'s error paths
In commit 79a77c5ac, we move ext4_mb_init_backend after the allocation
of s_locality_group to avoid memory leak in error path, but there are
still some other error paths in ext4_mb_init that need to do the same
work. So this patch adds all the error patch for ext4_mb_init. And all
the pointers are reset to NULL in case the caller may double free them.

Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-10-06 10:22:28 -04:00
Theodore Ts'o
e7d5f3156e ext4: rename ext4_claim_free_blocks() to ext4_claim_free_clusters()
This function really claims a number of free clusters, not blocks, so
rename it so it's clearer what's going on.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-09-09 19:14:51 -04:00
Theodore Ts'o
cff1dfd767 ext4: rename ext4_free_blocks_after_init() to ext4_free_clusters_after_init()
This function really returns the number of clusters after initializing
an uninitalized block bitmap has been initialized.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-09-09 19:12:51 -04:00
Theodore Ts'o
021b65bb1e ext4: Rename ext4_free_blks_{count,set}() to refer to clusters
The field bg_free_blocks_count_{lo,high} in the block group
descriptor has been repurposed to hold the number of free clusters for
bigalloc functions.  So rename the functions so it makes it easier to
read and audit the block allocation and block freeing code.

Note: at this point in bigalloc development we doesn't support
online resize, so this also makes it really obvious all of the places
we need to fix up to add support for online resize.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-09-09 19:08:51 -04:00
Aditya Kali
7b415bf60f ext4: Fix bigalloc quota accounting and i_blocks value
With bigalloc changes, the i_blocks value was not correctly set (it was still
set to number of blocks being used, but in case of bigalloc, we want i_blocks
to represent the number of clusters being used). Since the quota subsystem sets
the i_blocks value, this patch fixes the quota accounting and makes sure that
the i_blocks value is set correctly.

Signed-off-by: Aditya Kali <adityakali@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-09-09 19:04:51 -04:00
Theodore Ts'o
27baebb849 ext4: tune mballoc's default group prealloc size for bigalloc file systems
The default group preallocation size had been previously set to 512
blocks/clusters, regardless of the block/cluster size.  This is
probably too big for large cluster sizes.  So adjust the default so
that it is 2 megabytes or 32 clusters, whichever is larger.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-09-09 19:02:51 -04:00
Theodore Ts'o
24aaa8ef4e ext4: convert the free_blocks field in s_flex_groups to be free_clusters
Convert the free_blocks to be free_clusters to make the final revised
bigalloc changes easier to read/understand.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-09-09 18:58:51 -04:00
Theodore Ts'o
5704265188 ext4: convert s_{dirty,free}blocks_counter to s_{dirty,free}clusters_counter
Convert the percpu counters s_dirtyblocks_counter and
s_freeblocks_counter in struct ext4_super_info to be
s_dirtyclusters_counter and s_freeclusters_counter.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-09-09 18:56:51 -04:00
Theodore Ts'o
84130193e0 ext4: teach ext4_free_blocks() about bigalloc and clusters
The ext4_free_blocks() function now has two new flags that indicate
whether a partial cluster at the beginning or the end of the block
extents should be freed or not.  That will be up the caller (i.e.,
truncate), who can figure out whether partial clusters at the
beginning or the end of a block range can be freed.

We also have to update the ext4_mb_free_metadata() and
release_blocks_on_commit() machinery to be cluster-based, since it is
used by ext4_free_blocks().

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-09-09 18:50:51 -04:00
Theodore Ts'o
53accfa9f8 ext4: teach mballoc preallocation code about bigalloc clusters
In most of mballoc.c, we do everything in units of clusters, since the
block allocation bitmaps and buddy bitmaps are all denominated in
clusters.  The one place where we do deal with absolute block numbers
is in the code that handles the preallocation regions, since in the
case of inode-based preallocation regions, the start of the
preallocation region can't be relative to the beginning of the group.

So this adds a bit of complexity, where pa_pstart and pa_lstart are
block numbers, while pa_free, pa_len, and fe_len are denominated in
units of clusters.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-09-09 18:48:51 -04:00
Theodore Ts'o
7137d7a48e ext4: convert instances of EXT4_BLOCKS_PER_GROUP to EXT4_CLUSTERS_PER_GROUP
Change the places in fs/ext4/mballoc.c where EXT4_BLOCKS_PER_GROUP are
used to indicate the number of bits in a block bitmap (which is really
a cluster allocation bitmap in bigalloc file systems).  There are
still some places in the ext4 codebase where usage of
EXT4_BLOCKS_PER_GROUP needs to be audited/fixed, in code paths that
aren't used given the initial restricted assumptions for bigalloc.
These will need to be fixed before we can relax those restrictions.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-09-09 18:38:51 -04:00
Yu Jian
79a77c5ac3 ext4: prevent memory leaks from ext4_mb_init_backend() on error path
In ext4_mb_init(), if the s_locality_group allocation fails it will
currently cause the allocations made in ext4_mb_init_backend() to
be leaked.  Moving the ext4_mb_init_backend() allocation after the
s_locality_group allocation avoids that problem.

Signed-off-by: Yu Jian <yujian@whamcloud.com>
Signed-off-by: Andreas Dilger <adilger@whamcloud.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-08-01 17:41:46 -04:00
Yu Jian
48e6061bf4 ext4: use EXT4_BAD_INO for buddy cache to avoid colliding with valid inode #
Signed-off-by: Yu Jian <yujian@whamcloud.com>
Signed-off-by: Andreas Dilger <adilger@whamcloud.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-08-01 17:41:39 -04:00
Theodore Ts'o
9d8b9ec442 ext4: use ext4_msg() instead of printk in mballoc
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-08-01 17:41:35 -04:00
Theodore Ts'o
f18a5f21c2 ext4: use ext4_kvzalloc()/ext4_kvmalloc() for s_group_desc and s_group_info
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-08-01 08:45:38 -04:00
Yongqiang Yang
c3e94d1df9 ext4: let setup_new_group_blocks() set multiple bits at a time
Rename mb_set_bits() to ext4_set_bits() and make it a global function
so that setup_new_group_blocks() can use it.

Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-07-26 22:05:53 -04:00
Yongqiang Yang
4740b830ed ext4: let ext4_group_add_blocks() handle 0 blocks quickly
If ext4_group_add_blocks() is called with 0 block, make it return 0
without doing any extra work.

Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-07-26 21:51:08 -04:00
Yongqiang Yang
cc7365dfe4 ext4: let ext4_group_add_blocks() return an error code
This patch lets ext4_group_add_blocks() return an error code if it
fails, so that upper functions can handle error correctly.

Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-07-26 21:46:07 -04:00
Yongqiang Yang
0529155e8a ext4: rename ext4_add_groupblocks() to ext4_group_add_blocks()
Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-07-26 21:43:56 -04:00
Tao Ma
ced156e464 ext4: don't increment s_mb_buddies_generated in ext4_mb_release
In ext4_mb_release, we use s_mb_buddies_generated++.  Although
the output is OK, but I don't think we need this extra ++.

Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-07-23 16:18:05 -04:00
Tao Ma
529da704ad ext4: remove unnecessary ext4_get_group_info in ext4_mb_load_buddy
ext4_mb_load_buddy() calls ext4_get_group_info() for setting both
"grp" and "e4b->bd_info", but it could do "e4b->bd_info = grp".

Reported-by:  Andreas Dilger <adilger@whamcloud.com>
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-07-23 16:07:26 -04:00
Dan Ehrenberg
d7a1fee135 ext4: make the preallocation size be a multiple of stripe size
Previously, if a stripe width was provided, then it would be used
as the preallocation granularity, with no santiy checking and no
way to override this. Now, mb_prealloc_size defaults to the smallest
multiple of stripe size that is greater than or equal to the old
default mb_prealloc_size, and this can be overridden with the sysfs
interface.

Signed-off-by: Dan Ehrenberg <dehrenberg@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-07-17 21:11:30 -04:00
Tao Ma
caaf7a29d3 ext4: Fix a double free of sbi->s_group_info in ext4_mb_init_backend
If we meet with an error in ext4_mb_add_groupinfo, we kfree
sbi->s_group_info[group >> EXT4_DESC_PER_BLOCK_BITS(sb)], but fail to
reset it to NULL. So the caller ext4_mb_init_backend will try to kfree
it again and causes a double free. So fix it by resetting it to NULL.

Some typo in comments of mballoc.c are also changed.

Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-07-11 18:42:42 -04:00
Tao Ma
823ba01fc0 ext4: fix a race which could leak memory in ext4_groupinfo_create_slab()
In ext4_groupinfo_create_slab, we create ext4_groupinfo_caches within
ext4_grpinfo_slab_create_mutex, but set it outside the lock, and there
does exist some case that we may create it twice and causes a memory
leak.  So set it before we call mutex_unlock.

Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-07-11 18:26:01 -04:00
Tao Ma
22612283f7 ext4: Change the wrong param comment for ext4_trim_all_free
at ext4_trim_all_free() comment, there is no longer an @e4b parameter,
instead it is @group.

Reported-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-07-11 00:04:34 -04:00
Tao Ma
3d56b8d2c7 ext4: Speed up FITRIM by recording flags in ext4_group_info
In ext4, when FITRIM is called every time, we iterate all the
groups and do trim one by one. It is a bit time wasting if the
group has been trimmed and there is no change since the last
trim.

So this patch adds a new flag in ext4_group_info->bb_state to
indicate that the group has been trimmed, and it will be cleared
if some blocks is freed(in release_blocks_on_commit). Another
trim_minlen is added in ext4_sb_info to record the last minlen
we use to trim the volume, so that if the caller provide a small
one, we will go on the trim regardless of the bb_state.

A simple test with my intel x25m ssd:
df -h shows:
/dev/sdb1              40G   21G   17G  56% /mnt/ext4
Block size:               4096

run the FITRIM with the following parameter:
range.start = 0;
range.len = UINT64_MAX;
range.minlen = 1048576;

without the patch:
[root@boyu-tm linux-2.6]# time ./ftrim /mnt/ext4/a
real	0m5.505s
user	0m0.000s
sys	0m1.224s
[root@boyu-tm linux-2.6]# time ./ftrim /mnt/ext4/a
real	0m5.359s
user	0m0.000s
sys	0m1.178s
[root@boyu-tm linux-2.6]# time ./ftrim /mnt/ext4/a
real	0m5.228s
user	0m0.000s
sys	0m1.151s

with the patch:
[root@boyu-tm linux-2.6]# time ./ftrim /mnt/ext4/a
real	0m5.625s
user	0m0.000s
sys	0m1.269s
[root@boyu-tm linux-2.6]# time ./ftrim /mnt/ext4/a
real	0m0.002s
user	0m0.000s
sys	0m0.001s
[root@boyu-tm linux-2.6]# time ./ftrim /mnt/ext4/a
real	0m0.002s
user	0m0.000s
sys	0m0.001s

A big improvement for the 2nd and 3rd run.

Even after I delete some big image files, it is still much
faster than iterating the whole disk.

[root@boyu-tm test]# time ./ftrim /mnt/ext4/a
real	0m1.217s
user	0m0.000s
sys	0m0.196s

Cc: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Andreas Dilger <adilger.kernel@dilger.ca>
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-07-11 00:03:38 -04:00
Tao Ma
b3d4c2b10b ext4: Add new ext4 trim tracepoints
Add ext4_trim_extent and ext4_trim_all_free.

Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2011-07-11 00:01:52 -04:00