linux.git/fs/ext4/ialloc.c, branch v2.6.30

ext4: Fix potential inode allocation soft lockup in Orlov allocator

2009-04-23T01:00:36+00:00

If the Orlov allocator is having trouble finding an appropriate block
group, the fallback code could loop forever, causing a soft lockup
warning in find_group_orlov():

BUG: soft lockup - CPU#0 stuck for 61s! [cp:11728]
     ...
Pid: 11728, comm: cp Not tainted (2.6.30-rc1-dirty #77) Lenovo          
EIP: 0060:[] EFLAGS: 00000246 CPU: 0
EIP is at ext4_get_group_desc+0x54/0x9d
    ...
Call Trace:
 [] find_group_orlov+0x2ee/0x334
 [] ? sched_clock+0x8/0xb
 [] ext4_new_inode+0x2cf/0xb1a

Signed-off-by: "Theodore Ts'o"

ext4: really print the find_group_flex fallback warning only once

2009-04-14T11:37:40+00:00

Missing braces caused the warning to print more than once.

Signed-Off-By: Chuck Ebbert 
Signed-off-by: "Theodore Ts'o"

ext4: Use struct flex_groups to calculate get_orlov_stats()

2009-03-05T00:31:53+00:00

Instead of looping over all of the block groups in a flex group
summing their summary statistics, start tracking used_dirs in struct
flex_groups, and use struct flex_groups instead.  This should save a
bit of CPU for mkdir-heavy workloads.

Signed-off-by: "Theodore Ts'o"

ext4: Use atomic_t's in struct flex_groups

2009-03-05T00:09:10+00:00

Reduce pressure on the sb_bgl_lock family of locks by using atomic_t's
to track the number of free blocks and inodes in each flex_group.

Signed-off-by: "Theodore Ts'o"

ext4: New inode/block allocation algorithms for flex_bg filesystems

2009-03-12T16:18:34+00:00

The find_group_flex() inode allocator is now only used if the
filesystem is mounted using the "oldalloc" mount option.  It is
replaced with the original Orlov allocator that has been updated for
flex_bg filesystems (it should behave the same way if flex_bg is
disabled).  The inode allocator now functions by taking into account
each flex_bg group, instead of each block group, when deciding whether
or not it's time to allocate a new directory into a fresh flex_bg.

The block allocator has also been changed so that the first block
group in each flex_bg is preferred for use for storing directory
blocks.  This keeps directory blocks close together, which is good for
speeding up e2fsck since large directories are more likely to look
like this:

debugfs:  stat /home/tytso/Maildir/cur
Inode: 1844562   Type: directory    Mode:  0700   Flags: 0x81000
Generation: 1132745781    Version: 0x00000000:0000ad71
User: 15806   Group: 15806   Size: 1060864
File ACL: 0    Directory ACL: 0
Links: 2   Blockcount: 2072
Fragment:  Address: 0    Number: 0    Size: 0
 ctime: 0x499c0ff4:164961f4 -- Wed Feb 18 08:41:08 2009
 atime: 0x499c0ff4:00000000 -- Wed Feb 18 08:41:08 2009
 mtime: 0x49957f51:00000000 -- Fri Feb 13 09:10:25 2009
crtime: 0x499c0f57:00d51440 -- Wed Feb 18 08:38:31 2009
Size of extra inode fields: 28
BLOCKS:
(0):7348651, (1-258):7348654-7348911
TOTAL: 259

Signed-off-by: "Theodore Ts'o"

ext4: tighten restrictions on inode flags

2009-02-15T23:09:20+00:00

At the moment there are few restrictions on which flags may be set on
which inodes.  Specifically DIRSYNC may only be set on directories and
IMMUTABLE and APPEND may not be set on links.  Tighten that to disallow
TOPDIR being set on non-directories and only NODUMP and NOATIME to be set
on non-regular file, non-directories.

Introduces a flags masking function which masks flags based on mode and
use it during inode creation and when flags are set via the ioctl to
facilitate future consistency.

Signed-off-by: Duane Griffin 
Acked-by: Andreas Dilger 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: "Theodore Ts'o"

ext4: don't inherit inappropriate inode flags from parent

2009-02-15T23:57:26+00:00

At present INDEX and EXTENTS are the only flags that new ext4 inodes do
NOT inherit from their parent.  In addition prevent the flags DIRTY,
ECOMPR, IMAGIC, TOPDIR, HUGE_FILE and EXT_MIGRATE from being inherited. 
List inheritable flags explicitly to prevent future flags from
accidentally being inherited.

This fixes the TOPDIR flag inheritance bug reported at
http://bugzilla.kernel.org/show_bug.cgi?id=9866.

Signed-off-by: Duane Griffin 
Acked-by: Andreas Dilger 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: "Theodore Ts'o"

ext4: Use lowercase names of quota functions

2009-03-26T01:18:36+00:00

Use lowercase names of quota functions instead of old uppercase ones.

Signed-off-by: Jan Kara 
Acked-by: Mingming Cao 
CC: linux-ext4@vger.kernel.org

ext4: Print the find_group_flex() warning only once

2009-03-12T16:20:01+00:00

This is a short-term warning, and even printk_ratelimit() can result
in too much noise in system logs.  So only print it once as a warning.

Signed-off-by: "Theodore Ts'o"

ext4: fix ext4_free_inode() vs. ext4_claim_inode() race

2009-03-04T23:38:18+00:00

I was seeing fsck errors on inode bitmaps after a 4 thread
dbench run on a 4 cpu machine:

Inode bitmap differences: -50736 -(50752--50753) etc...

I believe that this is because ext4_free_inode() uses atomic
bitops, and although ext4_new_inode() *used* to also use atomic 
bitops for synchronization, commit 
393418676a7602e1d7d3f6e560159c65c8cbd50e changed this to use
the sb_bgl_lock, so that we could also synchronize against
read_inode_bitmap and initialization of uninit inode tables.

However, that change left ext4_free_inode using atomic bitops,
which I think leaves no synchronization between setting & 
unsetting bits in the inode table.

The below patch fixes it for me, although I wonder if we're 
getting at all heavy-handed with this spinlock...

Signed-off-by: Eric Sandeen 
Reviewed-by: Aneesh Kumar K.V 
Signed-off-by: "Theodore Ts'o"