Commit Graph

91 Commits

Author SHA1 Message Date
Brian Foster
3c58b5f809 xfs: reorganize xfs_iomap_prealloc_size to remove indentation
The majority of xfs_iomap_prealloc_size() executes within the
check for lack of default I/O size. Reverse the logic to remove the
extra indentation.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-03-22 16:04:23 -05:00
Mark Tinguely
e8108cedb1 xfs: fix xfs_iomap_eof_prealloc_initial_size type
Fix the return type of xfs_iomap_eof_prealloc_initial_size() to
xfs_fsblock_t to reflect the fact that the return value may be an
unsigned 64 bits if XFS_BIG_BLKNOS is defined.

Signed-off-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-03-07 12:29:59 -06:00
Brian Foster
e114b5fce6 xfs: increase prealloc size to double that of the previous extent
The updated speculative preallocation algorithm for handling sparse
files can becomes less effective in situations with a high number of
concurrent, sequential writers. The number of writers and amount of
available RAM affect the writeback bandwidth slicing algorithm,
which in turn affects the block allocation pattern of XFS. For
example, running 32 sequential writers on a system with 32GB RAM,
preallocs become fixed at a value of around 128MB (instead of
steadily increasing to the 8GB maximum as sequential writes
proceed).

Update the speculative prealloc heuristic to base the size of the
next prealloc on double the size of the preceding extent. This
preserves the original aggressive speculative preallocation
behavior and continues to accomodate sparse files at a slight cost
of increasing the size of preallocated data regions following holes
of sparse files.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-03-07 12:28:25 -06:00
Brian Foster
e78c420bfc xfs: fix potential infinite loop in xfs_iomap_prealloc_size()
If freesp == 0, we could end up in an infinite loop while squashing
the preallocation. Break the loop when we've killed the prealloc
entirely.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-03-07 12:21:39 -06:00
Dave Chinner
a1e16c2666 xfs: limit speculative prealloc size on sparse files
Speculative preallocation based on the current file size works well
for contiguous files, but is sub-optimal for sparse files where the
EOF preallocation can fill holes and result in large amounts of
zeros being written when it is not necessary.

The algorithm is modified to prevent EOF speculative preallocation
from triggering larger allocations on IO patterns of
truncate--to-zero-seek-write-seek-write-....  which results in
non-sparse files for large files. This, unfortunately, is the way cp
now behaves when copying sparse files and so needs to be fixed.

What this code does is that it looks at the existing extent adjacent
to the current EOF and if it determines that it is a hole we disable
speculative preallocation altogether. To avoid the next write from
doing a large prealloc, it takes the size of subsequent
preallocations from the current size of the existing EOF extent.
IOWs, if you leave a hole in the file, it resets preallocation
behaviour to the same as if it was a zero size file.

Example new behaviour:

$ xfs_io -f -c "pwrite 0 31m" \
            -c "pwrite 33m 1m" \
            -c "pwrite 128m 1m" \
            -c "fiemap -v" /mnt/scratch/blah
wrote 32505856/32505856 bytes at offset 0
31 MiB, 7936 ops; 0.0000 sec (1.608 GiB/sec and 421432.7439 ops/sec)
wrote 1048576/1048576 bytes at offset 34603008
1 MiB, 256 ops; 0.0000 sec (1.462 GiB/sec and 383233.5329 ops/sec)
wrote 1048576/1048576 bytes at offset 134217728
1 MiB, 256 ops; 0.0000 sec (1.719 GiB/sec and 450704.2254 ops/sec)
/mnt/scratch/blah:
 EXT: FILE-OFFSET      BLOCK-RANGE      TOTAL FLAGS
   0: [0..65535]:      96..65631        65536   0x0
   1: [65536..67583]:  hole              2048
   2: [67584..69631]:  67680..69727      2048   0x0
   3: [69632..262143]: hole             192512
   4: [262144..264191]: 262240..264287    2048   0x1

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-02-14 17:21:32 -06:00
Dave Chinner
4d559a3bcb xfs: limit speculative prealloc near ENOSPC thresholds
There is a window on small filesytsems where specualtive
preallocation can be larger than that ENOSPC throttling thresholds,
resulting in specualtive preallocation trying to reserve more space
than there is space available. This causes immediate ENOSPC to be
triggered, prealloc to be turned off and flushing to occur. One the
next write (i.e. next 4k page), we do exactly the same thing, and so
effective drive into synchronous 4k writes by triggering ENOSPC
flushing on every page while in the window between the prealloc size
and the ENOSPC prealloc throttle threshold.

Fix this by checking to see if the prealloc size would consume all
free space, and throttle it appropriately to avoid premature
ENOSPC...

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-01-24 11:08:55 -06:00
Brian Foster
27b5286792 xfs: add EOFBLOCKS inode tagging/untagging
Add the XFS_ICI_EOFBLOCKS_TAG inode tag to identify inodes with
speculatively preallocated blocks beyond EOF. An inode is tagged
when speculative preallocation occurs and untagged either via
truncate down or when post-EOF blocks are freed via release or
reclaim.

The tag management is intentionally not aggressive to prefer
simplicity over the complexity of handling all the corner cases
under which post-EOF blocks could be freed (i.e., forward
truncation, fallocate, write error conditions, etc.). This means
that a tagged inode may or may not have post-EOF blocks after a
period of time. The tag is eventually cleared when the inode is
released or reclaimed.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-11-08 14:20:44 -06:00
Dave Chinner
2455881c0b xfs: introduce XFS_BMAPI_STACK_SWITCH
Certain allocation paths through xfs_bmapi_write() are in situations
where we have limited stack available. These are almost always in
the buffered IO writeback path when convertion delayed allocation
extents to real extents.

The current stack switch occurs for userdata allocations, which
means we also do stack switches for preallocation, direct IO and
unwritten extent conversion, even those these call chains have never
been implicated in a stack overrun.

Hence, let's target just the single stack overun offended for stack
switches. To do that, introduce a XFS_BMAPI_STACK_SWITCH flag that
the caller can pass xfs_bmapi_write() to indicate it should switch
stacks if it needs to do allocation.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-10-18 17:41:56 -05:00
Dave Chinner
9aa05000f2 xfs: xfs_sync_data is redundant.
We don't do any data writeback from XFS any more - the VFS is
completely responsible for that, including for freeze. We can
replace the remaining caller with a VFS level function that
achieves the same thing, but without conflicting with current
writeback work.

This means we can remove the flush_work and xfs_flush_inodes() - the
VFS functionality completely replaces the internal flush queue for
doing this writeback work in a separate context to avoid stack
overruns.

This does have one complication - it cannot be called with page
locks held.  Hence move the flushing of delalloc space when ENOSPC
occurs back up into xfs_file_aio_buffered_write when we don't hold
any locks that will stall writeback.

Unfortunately, writeback_inodes_sb_if_idle() is not sufficient to
trigger delalloc conversion fast enough to prevent spurious ENOSPC
whent here are hundreds of writers, thousands of small files and GBs
of free RAM.  Hence we need to use sync_sb_inodes() to block callers
while we wait for writeback like the previous xfs_flush_inodes
implementation did.

That means we have to hold the s_umount lock here, but because this
call can nest inside i_mutex (the parent directory in the create
case, held by the VFS), we have to use down_read_trylock() to avoid
potential deadlocks. In practice, this trylock will succeed on
almost every attempt as unmount/remount type operations are
exceedingly rare.

Note: we always need to pass a count of zero to
generic_file_buffered_write() as the previously written byte count.
We only do this by accident before this patch by the virtue of ret
always being zero when there are no errors. Make this explicit
rather than needing to specifically zero ret in the ENOSPC retry
case.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Tested-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-10-17 12:01:25 -05:00
Linus Torvalds
a0e881b7c1 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull second vfs pile from Al Viro:
 "The stuff in there: fsfreeze deadlock fixes by Jan (essentially, the
  deadlock reproduced by xfstests 068), symlink and hardlink restriction
  patches, plus assorted cleanups and fixes.

  Note that another fsfreeze deadlock (emergency thaw one) is *not*
  dealt with - the series by Fernando conflicts a lot with Jan's, breaks
  userland ABI (FIFREEZE semantics gets changed) and trades the deadlock
  for massive vfsmount leak; this is going to be handled next cycle.
  There probably will be another pull request, but that stuff won't be
  in it."

Fix up trivial conflicts due to unrelated changes next to each other in
drivers/{staging/gdm72xx/usb_boot.c, usb/gadget/storage_common.c}

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (54 commits)
  delousing target_core_file a bit
  Documentation: Correct s_umount state for freeze_fs/unfreeze_fs
  fs: Remove old freezing mechanism
  ext2: Implement freezing
  btrfs: Convert to new freezing mechanism
  nilfs2: Convert to new freezing mechanism
  ntfs: Convert to new freezing mechanism
  fuse: Convert to new freezing mechanism
  gfs2: Convert to new freezing mechanism
  ocfs2: Convert to new freezing mechanism
  xfs: Convert to new freezing code
  ext4: Convert to new freezing mechanism
  fs: Protect write paths by sb_start_write - sb_end_write
  fs: Skip atime update on frozen filesystem
  fs: Add freezing handling to mnt_want_write() / mnt_drop_write()
  fs: Improve filesystem freezing handling
  switch the protection of percpu_counter list to spinlock
  nfsd: Push mnt_want_write() outside of i_mutex
  btrfs: Push mnt_want_write() outside of i_mutex
  fat: Push mnt_want_write() outside of i_mutex
  ...
2012-08-01 10:26:23 -07:00
Jan Kara
d9457dc056 xfs: Convert to new freezing code
Generic code now blocks all writers from standard write paths. So we add
blocking of all writers coming from ioctl (we get a protection of ioctl against
racing remount read-only as a bonus) and convert xfs_file_aio_write() to a
non-racy freeze protection. We also keep freeze protection on transaction
start to block internal filesystem writes such as removal of preallocated
blocks.

CC: Ben Myers <bpm@sgi.com>
CC: Alex Elder <elder@kernel.org>
CC: xfs@oss.sgi.com
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-31 09:45:48 +04:00
Dave Chinner
32972383ca xfs: make largest supported offset less shouty
XFS_MAXIOFFSET() is just a simple macro that resolves to
mp->m_maxioffset. It doesn't need to exist, and it just makes the
code unnecessarily loud and shouty.

Make it quiet and easy to read.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-06-14 12:28:24 -05:00
Dave Chinner
d2c2819117 xfs: m_maxioffset is redundant
The m_maxioffset field in the struct xfs_mount contains the same
value as the superblock s_maxbytes field. There is no need to carry
two copies of this limit around, so use the VFS superblock version.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-06-14 12:28:22 -05:00
Dave Chinner
ea562ed6e7 xfs: fix delalloc quota accounting on failure
xfstest 270 was causing quota reservations way beyond what was sane
(ten to hundreds of TB) for a 4GB filesystem. There's a sign problem
in the error handling path of xfs_bmapi_reserve_delalloc() because
xfs_trans_unreserve_quota_nblks() simple negates the value passed -
which doesn't work for an unsigned variable. This causes
reservations of close to 2^32 block instead of removing a
reservation of a handful of blocks.

Fix the same problem in the other xfs_trans_unreserve_quota_nblks()
callers where unsigned integer variables are used, too.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-21 10:45:43 -05:00
Dave Chinner
ad1e95c54e xfs: clean up xfs_bit.h includes
With the removal of xfs_rw.h and other changes over time, xfs_bit.h
is being included in many files that don't actually need it. Clean
up the includes as necessary.

Also move the only-used-once xfs_ialloc_find_free() static inline
function out of a header file that is widely included to reduce
the number of needless dependencies on xfs_bit.h.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-14 16:21:00 -05:00
Dave Chinner
2a0ec1d9ed xfs: move xfs_get_extsz_hint() and kill xfs_rw.h
The only thing left in xfs_rw.h is a function prototype for an inode
function.  Move that to xfs_inode.h, and kill xfs_rw.h.

Also move the function implementing the prototype from xfs_rw.c to
xfs_inode.c so we only have one function left in xfs_rw.c

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-14 16:20:58 -05:00
Dave Chinner
60a34607b2 xfs: move xfsagino_t to xfs_types.h
Untangle the header file includes a bit by moving the definition of
xfs_agino_t to xfs_types.h. This removes the dependency that xfs_ag.h has on
xfs_inum.h, meaning we don't need to include xfs_inum.h everywhere we include
xfs_ag.h.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-14 16:20:54 -05:00
Dave Chinner
3ed9116e8a xfs: limit specualtive delalloc to maxioffset
Speculative delayed allocation beyond EOF near the maximum supported
file offset can result in creating delalloc extents beyond
mp->m_maxioffset (8EB). These can never be trimmed during
xfs_free_eof_blocks() because they are beyond mp->m_maxioffset, and
that results in assert failures in xfs_fs_destroy_inode() due to
delalloc blocks still being present. xfstests 071 exposes this
problem.

Limit speculative delalloc to mp->m_maxioffset to avoid this
problem.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-14 16:20:39 -05:00
Dave Chinner
507630b29f xfs: use shared ilock mode for direct IO writes by default
For the direct IO write path, we only really need the ilock to be taken in
exclusive mode during IO submission if we need to do extent allocation
instead of all the time.

Change the block mapping code to take the ilock in shared mode for the
initial block mapping, and only retake it exclusively when we actually
have to perform extent allocations.  We were already dropping the ilock
for the transaction allocation, so this doesn't introduce new race windows.

Based on an earlier patch from Dave Chinner.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-14 16:20:21 -05:00
Christoph Hellwig
84803fb782 xfs: log file size updates as part of unwritten extent conversion
If we convert and unwritten extent past the current i_size log the size update
as part of the extent manipulation transactions instead of doing an unlogged
metadata update later.

Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-03-05 11:53:16 -06:00
Christoph Hellwig
ce7ae151dd xfs: remove the i_size field in struct xfs_inode
There is no fundamental need to keep an in-memory inode size copy in the XFS
inode.  We already have the on-disk value in the dinode, and the separate
in-memory copy that we need for regular files only in the XFS inode.

Remove the xfs_inode i_size field and change the XFS_ISIZE macro to use the
VFS inode i_size field for regular files.  Switch code that was directly
accessing the i_size field in the xfs_inode to XFS_ISIZE, or in cases where
we are limited to regular files direct access of the VFS inode i_size field.

This also allows dropping some fairly complicated code in the write path
which dealt with keeping the xfs_inode i_size uptodate with the VFS i_size
that is getting updated inside ->write_end.

Note that we do not bother resetting the VFS i_size when truncating a file
that gets freed to zero as there is no point in doing so because the VFS inode
is no longer in use at this point.  Just relax the assert in xfs_ifree to
only check the on-disk size instead.

Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-01-17 15:08:53 -06:00
Christoph Hellwig
bf322d983e xfs: cleanup xfs_iomap_eof_align_last_fsb
Replace the nasty if, else if, elseif condition with more natural C flow
that expressed the logic we want here better.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2012-01-13 12:11:46 -06:00
Christoph Hellwig
ddc3415aba xfs: simplify xfs_trans_ijoin* again
There is no reason to keep a reference to the inode even if we unlock
it during transaction commit because we never drop a reference between
the ijoin and commit.  Also use this fact to merge xfs_trans_ijoin_ref
back into xfs_trans_ijoin - the third argument decides if an unlock
is needed now.

I'm actually starting to wonder if allowing inodes to be unlocked
at transaction commit really is worth the effort.  The only real
benefit is that they can be unlocked earlier when commiting a
synchronous transactions, but that could be solved by doing the
log force manually after the unlock, too.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:08 -05:00
Dave Chinner
c0dc7828af xfs: rename xfs_bmapi to xfs_bmapi_write
Now that all the read-only users of xfs_bmapi have been converted to
use xfs_bmapi_read(), we can remove all the read-only handling cases
from xfs_bmapi().

Once this is done, rename xfs_bmapi to xfs_bmapi_write to reflect
the fact it is for allocation only. This enables us to kill the
XFS_BMAPI_WRITE flag as well.

Also clean up xfs_bmapi_write to the style used in the newly added
xfs_bmapi_read/delay functions.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:04 -05:00
Christoph Hellwig
4403280aa5 xfs: introduce xfs_bmapi_delay()
Delalloc reservations are much simpler than allocations, so give
them a separate bmapi-level interface.  Using the previously added
xfs_bmapi_reserve_delalloc we get a function that is only minimally
more complicated than xfs_bmapi_read, which is far from the complexity
in xfs_bmapi.  Also remove the XFS_BMAPI_DELAY code after switching
over the only user to xfs_bmapi_delay.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:04 -05:00
Dave Chinner
5c8ed2021f xfs: introduce xfs_bmapi_read()
xfs_bmapi() currently handles both extent map reading and
allocation. As a result, the code is littered with "if (wr)"
branches to conditionally do allocation operations if required.
This makes the code much harder to follow and causes significant
indent issues with the code.

Given that read mapping is much simpler than allocation, we can
split out read mapping from xfs_bmapi() and reuse the logic that
we have already factored out do do all the hard work of handling the
extent map manipulations. The results in a much simpler function for
the common extent read operations, and will allow the allocation
code to be simplified in another commit.

Once xfs_bmapi_read() is implemented, convert all the callers of
xfs_bmapi() that are only reading extents to use the new function.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:03 -05:00
Dave Chinner
6d4a8ecb34 xfs: rename xfs_cmn_err_fsblock_zero()
The "cmn_err" part of the function name is no longer relevant. Rename
the function to xfs_alert_fsblock_zero() to match the new logging
API.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2011-03-07 10:06:35 +11:00
Dave Chinner
6a19d9393a xfs: convert xfs_cmn_err to xfs_alert_tag
Continue the conversion of the old cmn_err interface be converting
all the conditional panic tag errors to xfs_alert_tag() and then
removing xfs_cmn_err().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2011-03-07 10:02:35 +11:00
Dave Chinner
b8fc82630a xfs: speculative delayed allocation uses rounddown_power_of_2 badly
rounddown_power_of_2() returns an undefined result when passed a
value of zero. The specualtive delayed allocation code is doing this
when the inode is zero length. Hence occasionally the preallocation
is much, much larger than is necessary (e.g. 8GB for a 270 _byte_
file). Ensure we don't even pass a zero value to this function so
the result of preallocation is always the desired size.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
2011-01-28 09:05:35 -06:00
Dave Chinner
055388a318 xfs: dynamic speculative EOF preallocation
Currently the size of the speculative preallocation during delayed
allocation is fixed by either the allocsize mount option of a
default size. We are seeing a lot of cases where we need to
recommend using the allocsize mount option to prevent fragmentation
when buffered writes land in the same AG.

Rather than using a fixed preallocation size by default (up to 64k),
make it dynamic by basing it on the current inode size. That way the
EOF preallocation will increase as the file size increases.  Hence
for streaming writes we are much more likely to get large
preallocations exactly when we need it to reduce fragementation.

For default settings, the size of the initial extents is determined
by the number of parallel writers and the amount of memory in the
machine. For 4GB RAM and 4 concurrent 32GB file writes:

EXT: FILE-OFFSET           BLOCK-RANGE          AG AG-OFFSET                 TOTAL
   0: [0..1048575]:         1048672..2097247      0 (1048672..2097247)      1048576
   1: [1048576..2097151]:   5242976..6291551      0 (5242976..6291551)      1048576
   2: [2097152..4194303]:   12583008..14680159    0 (12583008..14680159)    2097152
   3: [4194304..8388607]:   25165920..29360223    0 (25165920..29360223)    4194304
   4: [8388608..16777215]:  58720352..67108959    0 (58720352..67108959)    8388608
   5: [16777216..33554423]: 117440584..134217791  0 (117440584..134217791) 16777208
   6: [33554424..50331511]: 184549056..201326143  0 (184549056..201326143) 16777088
   7: [50331512..67108599]: 251657408..268434495  0 (251657408..268434495) 16777088

and for 16 concurrent 16GB file writes:

 EXT: FILE-OFFSET           BLOCK-RANGE          AG AG-OFFSET                 TOTAL
   0: [0..262143]:          2490472..2752615      0 (2490472..2752615)       262144
   1: [262144..524287]:     6291560..6553703      0 (6291560..6553703)       262144
   2: [524288..1048575]:    13631592..14155879    0 (13631592..14155879)     524288
   3: [1048576..2097151]:   30408808..31457383    0 (30408808..31457383)    1048576
   4: [2097152..4194303]:   52428904..54526055    0 (52428904..54526055)    2097152
   5: [4194304..8388607]:   104857704..109052007  0 (104857704..109052007)  4194304
   6: [8388608..16777215]:  209715304..218103911  0 (209715304..218103911)  8388608
   7: [16777216..33554423]: 452984848..469762055  0 (452984848..469762055) 16777208

Because it is hard to take back specualtive preallocation, cases
where there are large slow growing log files on a nearly full
filesystem may cause premature ENOSPC. Hence as the filesystem nears
full, the maximum dynamic prealloc size іs reduced according to this
table (based on 4k block size):

freespace       max prealloc size
  >5%             full extent (8GB)
  4-5%             2GB (8GB >> 2)
  3-4%             1GB (8GB >> 3)
  2-3%           512MB (8GB >> 4)
  1-2%           256MB (8GB >> 5)
  <1%            128MB (8GB >> 6)

This should reduce the amount of space held in speculative
preallocation for such cases.

The allocsize mount option turns off the dynamic behaviour and fixes
the prealloc size to whatever the mount option specifies. i.e. the
behaviour is unchanged.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
2011-01-04 11:35:03 +11:00
Christoph Hellwig
a206c817c8 xfs: kill xfs_iomap
Opencode the xfs_iomap code in it's two callers.  The overlap of
passed flags already was minimal and will be further reduced in the
next patch.

As a side effect the BMAPI_* flags for xfs_bmapi and the IO_* flags
for I/O end processing are merged into a single set of flags, which
should be a bit more descriptive of the operation we perform.

Also improve the tracing by giving each caller it's own type set of
tracepoints.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-12-16 16:05:51 -06:00
Christoph Hellwig
405f804294 xfs: cleanup the xfs_iomap_write_* helpers
Remove passing the BMAPI_* flags to these helpers, in
xfs_iomap_write_direct the check BMAPI_DIRECT was always true, and
in the xfs_iomap_write_delay path is was never checked at all.
Remove the nmap return value as we never make use of it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-12-16 16:05:47 -06:00
Christoph Hellwig
f2bde9b89b xfs: small cleanups for xfs_iomap / __xfs_get_blocks
Remove the flags argument to  __xfs_get_blocks as we can easily derive
it from the direct argument, and remove the unused BMAPI_MMAP flag.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2010-07-26 13:16:42 -05:00
Christoph Hellwig
3070451eea xfs: reduce stack usage in xfs_iomap
xfs_iomap passes a xfs_bmbt_irec pointer to xfs_iomap_write_direct and
xfs_iomap_write_allocate to give them the results of our read-only
xfs_bmapi query.  Instead of allocating a new xfs_bmbt_irec on stack
for the next call to xfs_bmapi re use the one we got passed as it's not
used after this point.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2010-07-26 13:16:42 -05:00
Christoph Hellwig
b4e9181e77 xfs: remove unused delta tracking code in xfs_bmapi
This code was introduced four years ago in commit
3e57ecf640 without any review and has
been unused since.  Remove it just as the rest of the code introduced
in that commit to reduce that stack usage and complexity in this central
piece of code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2010-07-26 13:16:39 -05:00
Christoph Hellwig
898621d5a7 xfs: simplify inode to transaction joining
Currently we need to either call IHOLD or xfs_trans_ihold on an inode when
joining it to a transaction via xfs_trans_ijoin.

This patches instead makes xfs_trans_ijoin usable on it's own by doing
an implicity xfs_trans_ihold, which also allows us to drop the third
argument.  For the case where we want to hold a reference on the inode
a xfs_trans_ijoin_ref wrapper is added which does the IHOLD and marks
the inode for needing an xfs_iput.  In addition to the cleaner interface
to the caller this also simplifies the implementation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2010-07-26 13:16:36 -05:00
Christoph Hellwig
3400777ff0 xfs: remove unneeded #include statements
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
2010-07-26 13:16:33 -05:00
Christoph Hellwig
288699feca xfs: drop dmapi hooks
Dmapi support was never merged upstream, but we still have a lot of hooks
bloating XFS for it, all over the fast pathes of the filesystem.

This patch drops over 700 lines of dmapi overhead.  If we'll ever get HSM
support in mainline at least the namespace events can be done much saner
in the VFS instead of the individual filesystem, so it's not like this
is much help for future work.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2010-07-26 13:16:33 -05:00
Christoph Hellwig
b4ed4626a9 xfs: mark xfs_iomap_write_ helpers static
And also drop a useless argument to xfs_iomap_write_direct.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-05-19 09:58:20 -05:00
Christoph Hellwig
207d041602 xfs: kill struct xfs_iomap
Now that struct xfs_iomap contains exactly the same units as struct
xfs_bmbt_irec we can just use the latter directly in the aops code.
Replace the missing IOMAP_NEW flag with a new boolean output
parameter to xfs_iomap.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-05-19 09:58:17 -05:00
Christoph Hellwig
e513182d4d xfs: report iomap_bn in block base
Report the iomap_bn field of struct xfs_iomap in terms of filesystem
blocks instead of in terms of bytes.  Shift the byte conversions
into the caller, and replace the IOMAP_DELAY and IOMAP_HOLE flag
checks with checks for HOLESTARTBLOCK and DELAYSTARTBLOCK.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-05-19 09:58:17 -05:00
Christoph Hellwig
8699bb0a48 xfs: report iomap_offset and iomap_bsize in block base
Report the iomap_offset and iomap_bsize fields of struct xfs_iomap
in terms of fsblocks instead of in terms of disk blocks.  Shift the
byte conversions into the callers temporarily, but they will
disappear or get cleaned up later.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-05-19 09:58:17 -05:00
Christoph Hellwig
9563b3d899 xfs: remove iomap_delta
The iomap_delta field in struct xfs_iomap just contains the
difference between the offset passed to xfs_iomap and the
iomap_offset.  Just calculate it in the only caller that cares.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-05-19 09:58:17 -05:00
Christoph Hellwig
046f1685bb xfs: remove iomap_target
Instead of using the iomap_target field in struct xfs_iomap
and the IOMAP_REALTIME flag just use the already existing
xfs_find_bdev_for_inode helper.  There's some fallout as we
need to pass the inode in a few more places, which we also
use to sanitize some calling conventions.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-05-19 09:58:16 -05:00
Christoph Hellwig
826bf0adce xfs: limit xfs_imap_to_bmap to a single mapping
We only call xfs_iomap for single mappings anyway, so remove all
code dealing with multiple mappings from xfs_imap_to_bmap and add
asserts that we never get results that we do not expect.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-05-19 09:58:16 -05:00
Christoph Hellwig
0b1b213fcf xfs: event tracing support
Convert the old xfs tracing support that could only be used with the
out of tree kdb and xfsidbg patches to use the generic event tracer.

To use it make sure CONFIG_EVENT_TRACING is enabled and then enable
all xfs trace channels by:

   echo 1 > /sys/kernel/debug/tracing/events/xfs/enable

or alternatively enable single events by just doing the same in one
event subdirectory, e.g.

   echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable

or set more complex filters, etc. In Documentation/trace/events.txt
all this is desctribed in more detail.  To reads the events do a

   cat /sys/kernel/debug/tracing/trace

Compared to the last posting this patch converts the tracing mostly to
the one tracepoint per callsite model that other users of the new
tracing facility also employ.  This allows a very fine-grained control
of the tracing, a cleaner output of the traces and also enables the
perf tool to use each tracepoint as a virtual performance counter,
     allowing us to e.g. count how often certain workloads git various
     spots in XFS.  Take a look at

    http://lwn.net/Articles/346470/

for some examples.

Also the btree tracing isn't included at all yet, as it will require
additional core tracing features not in mainline yet, I plan to
deliver it later.

And the really nice thing about this patch is that it actually removes
many lines of code while adding this nice functionality:

 fs/xfs/Makefile                |    8
 fs/xfs/linux-2.6/xfs_acl.c     |    1
 fs/xfs/linux-2.6/xfs_aops.c    |   52 -
 fs/xfs/linux-2.6/xfs_aops.h    |    2
 fs/xfs/linux-2.6/xfs_buf.c     |  117 +--
 fs/xfs/linux-2.6/xfs_buf.h     |   33
 fs/xfs/linux-2.6/xfs_fs_subr.c |    3
 fs/xfs/linux-2.6/xfs_ioctl.c   |    1
 fs/xfs/linux-2.6/xfs_ioctl32.c |    1
 fs/xfs/linux-2.6/xfs_iops.c    |    1
 fs/xfs/linux-2.6/xfs_linux.h   |    1
 fs/xfs/linux-2.6/xfs_lrw.c     |   87 --
 fs/xfs/linux-2.6/xfs_lrw.h     |   45 -
 fs/xfs/linux-2.6/xfs_super.c   |  104 ---
 fs/xfs/linux-2.6/xfs_super.h   |    7
 fs/xfs/linux-2.6/xfs_sync.c    |    1
 fs/xfs/linux-2.6/xfs_trace.c   |   75 ++
 fs/xfs/linux-2.6/xfs_trace.h   | 1369 +++++++++++++++++++++++++++++++++++++++++
 fs/xfs/linux-2.6/xfs_vnode.h   |    4
 fs/xfs/quota/xfs_dquot.c       |  110 ---
 fs/xfs/quota/xfs_dquot.h       |   21
 fs/xfs/quota/xfs_qm.c          |   40 -
 fs/xfs/quota/xfs_qm_syscalls.c |    4
 fs/xfs/support/ktrace.c        |  323 ---------
 fs/xfs/support/ktrace.h        |   85 --
 fs/xfs/xfs.h                   |   16
 fs/xfs/xfs_ag.h                |   14
 fs/xfs/xfs_alloc.c             |  230 +-----
 fs/xfs/xfs_alloc.h             |   27
 fs/xfs/xfs_alloc_btree.c       |    1
 fs/xfs/xfs_attr.c              |  107 ---
 fs/xfs/xfs_attr.h              |   10
 fs/xfs/xfs_attr_leaf.c         |   14
 fs/xfs/xfs_attr_sf.h           |   40 -
 fs/xfs/xfs_bmap.c              |  507 +++------------
 fs/xfs/xfs_bmap.h              |   49 -
 fs/xfs/xfs_bmap_btree.c        |    6
 fs/xfs/xfs_btree.c             |    5
 fs/xfs/xfs_btree_trace.h       |   17
 fs/xfs/xfs_buf_item.c          |   87 --
 fs/xfs/xfs_buf_item.h          |   20
 fs/xfs/xfs_da_btree.c          |    3
 fs/xfs/xfs_da_btree.h          |    7
 fs/xfs/xfs_dfrag.c             |    2
 fs/xfs/xfs_dir2.c              |    8
 fs/xfs/xfs_dir2_block.c        |   20
 fs/xfs/xfs_dir2_leaf.c         |   21
 fs/xfs/xfs_dir2_node.c         |   27
 fs/xfs/xfs_dir2_sf.c           |   26
 fs/xfs/xfs_dir2_trace.c        |  216 ------
 fs/xfs/xfs_dir2_trace.h        |   72 --
 fs/xfs/xfs_filestream.c        |    8
 fs/xfs/xfs_fsops.c             |    2
 fs/xfs/xfs_iget.c              |  111 ---
 fs/xfs/xfs_inode.c             |   67 --
 fs/xfs/xfs_inode.h             |   76 --
 fs/xfs/xfs_inode_item.c        |    5
 fs/xfs/xfs_iomap.c             |   85 --
 fs/xfs/xfs_iomap.h             |    8
 fs/xfs/xfs_log.c               |  181 +----
 fs/xfs/xfs_log_priv.h          |   20
 fs/xfs/xfs_log_recover.c       |    1
 fs/xfs/xfs_mount.c             |    2
 fs/xfs/xfs_quota.h             |    8
 fs/xfs/xfs_rename.c            |    1
 fs/xfs/xfs_rtalloc.c           |    1
 fs/xfs/xfs_rw.c                |    3
 fs/xfs/xfs_trans.h             |   47 +
 fs/xfs/xfs_trans_buf.c         |   62 -
 fs/xfs/xfs_vnodeops.c          |    8
 70 files changed, 2151 insertions(+), 2592 deletions(-)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-14 23:08:16 -06:00
Christoph Hellwig
80641dc66a xfs: I/O completion handlers must use NOFS allocations
When completing I/O requests we must not allow the memory allocator to
recurse into the filesystem, as we might deadlock on waiting for the
I/O completion otherwise.  The only thing currently allocating normal
GFP_KERNEL memory is the allocation of the transaction structure for
the unwritten extent conversion.  Add a memflags argument to
_xfs_trans_alloc to allow controlling the allocator behaviour.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Thomas Neumann <tneumann@users.sourceforge.net>
Tested-by: Thomas Neumann <tneumann@users.sourceforge.net>
Reviewed-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-11 15:11:20 -06:00
Christoph Hellwig
ef14f0c157 xfs: use generic Posix ACL code
This patch rips out the XFS ACL handling code and uses the generic
fs/posix_acl.c code instead.  The ondisk format is of course left
unchanged.

This also introduces the same ACL caching all other Linux filesystems do
by adding pointers to the acl and default acl in struct xfs_inode.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
2009-06-10 17:07:47 +02:00
Christoph Hellwig
7d095257e3 xfs: kill xfs_qmops
Kill the quota ops function vector and replace it with direct calls or
stubs in the CONFIG_XFS_QUOTA=n case.

Make sure we check XFS_IS_QUOTA_RUNNING in the right spots.  We can remove
the number of those checks because the XFS_TRANS_DQ_DIRTY flag can't be set
otherwise.

This brings us back closer to the way this code worked in IRIX and earlier
Linux versions, but we keep a lot of the more useful factoring of common
code.

Eventually we should also kill xfs_qm_bhv.c, but that's left for a later
patch.

Reduces the size of the source code by about 250 lines and the size of
XFS module by about 1.5 kilobytes with quotas enabled:

   text	   data	    bss	    dec	    hex	filename
 615957	   2960	   3848	 622765	  980ad	fs/xfs/xfs.o
 617231	   3152	   3848	 624231	  98667	fs/xfs/xfs.o.old

Fallout:

 - xfs_qm_dqattach is split into xfs_qm_dqattach_locked which expects
   the inode locked and xfs_qm_dqattach which does the locking around it,
   thus removing XFS_QMOPT_ILOCKED.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
2009-06-08 15:33:32 +02:00
Dave Chinner
8de2bf937a xfs: remove xfs_flush_space
The only thing we need to do now when we get an ENOSPC condition during delayed
allocation reservation is flush all the other inodes with delalloc blocks on
them and retry without EOF preallocation. Remove the unneeded mess that is
xfs_flush_space() and just call xfs_flush_inodes() directly from
xfs_iomap_write_delay().

Also, change the location of the retry label to avoid trying to do EOF
preallocation because we don't want to do that at ENOSPC. This enables us to
remove the BMAPI_SYNC flag as it is no longer used.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2009-04-06 18:49:12 +02:00