Commit Graph

1542 Commits

Author SHA1 Message Date
Linus Torvalds
b305956abc Merge branch 'for-linus' of git://oss.sgi.com/xfs/xfs
* 'for-linus' of git://oss.sgi.com/xfs/xfs: (52 commits)
  fs/xfs: Correct NULL test
  xfs: optimize log flushing in xfs_fsync
  xfs: only clear the suid bit once in xfs_write
  xfs: kill xfs_bawrite
  xfs: log changed inodes instead of writing them synchronously
  xfs: remove invalid barrier optimization from xfs_fsync
  xfs: kill the unused XFS_QMOPT_* flush flags V2
  xfs: Use delay write promotion for dquot flushing
  xfs: Sort delayed write buffers before dispatch
  xfs: Don't issue buffer IO direct from AIL push V2
  xfs: Use delayed write for inodes rather than async V2
  xfs: Make inode reclaim states explicit
  xfs: more reserved blocks fixups
  xfs: turn off sign warnings
  xfs: don't hold onto reserved blocks on remount,ro
  xfs: quota limit statvfs available blocks
  xfs: replace KM_LARGE with explicit vmalloc use
  xfs: cleanup up xfs_log_force calling conventions
  xfs: kill XLOG_VEC_SET_TYPE
  xfs: remove duplicate buffer flags
  ...
2010-02-26 17:18:52 -08:00
Linus Torvalds
f24407d2bd Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/xfs-vipt
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/xfs-vipt:
  xfs: fix xfs to work with Virtually Indexed architectures
  sh: add mm API for DMA to vmalloc/vmap areas
  arm: add mm API for DMA to vmalloc/vmap areas
  parisc: add mm API for DMA to vmalloc/vmap areas
  mm: add coherence API for DMA to vmalloc/vmap areas
2010-02-26 17:05:10 -08:00
Julia Lawall
d67b1b0325 fs/xfs: Correct NULL test
Test the value that was just allocated rather than the previously tested one.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@r@
expression *x;
expression e;
identifier l;
@@

if (x == NULL || ...) {
    ... when forall
    return ...; }
... when != goto l;
    when != x = e
    when != &x
*x == NULL
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-02-13 13:22:53 -06:00
Christoph Hellwig
180040b89e xfs: optimize log flushing in xfs_fsync
If we have a pinned inode it must have a log item attached to it.
Usually that log item will have ili_last_lsn already set, in which
case we only need to flush the log up to that LSN instead of doing a
full log force.  This gives speedups of about 5% in some fsync heavy
workloads.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-02-12 13:45:14 -06:00
Christoph Hellwig
87185517de xfs: only clear the suid bit once in xfs_write
file_remove_suid already calls into ->setattr to clear the suid and
sgid bits if needed, no need to start a second transaction to do it
ourselves.

Note that xfs_write_clear_setuid issues a sync transaction while the
path through ->setattr doesn't, but that is consistant with the
other filesystems.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-02-12 13:43:57 -06:00
James Bottomley
73c77e2ccc xfs: fix xfs to work with Virtually Indexed architectures
xfs_buf.c includes what is essentially a hand rolled version of
blk_rq_map_kern().  In order to work properly with the vmalloc buffers
that xfs uses, this hand rolled routine must also implement the flushing
API for vmap/vmalloc areas.

[style updates from hch@lst.de]
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-02-05 12:32:35 -06:00
Dave Chinner
5322892d86 xfs: kill xfs_bawrite
There are no more users of this function left in the XFS code
now that we've switched everything to delayed write flushing.
Remove it.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-02-04 10:09:14 +11:00
Christoph Hellwig
07fec73625 xfs: log changed inodes instead of writing them synchronously
When an inode has already be flushed delayed write,
xfs_inode_clean() returns true and hence xfs_fs_write_inode() can
return on a synchronous inode write without having written the
inode. Currently these sycnhronous writes only come sync(1),
unmount, a sycnhronous NFS export and cachefiles so should be
relatively rare and out of common performance paths.

Realistically, a synchronous inode write is not necessary here; we
can avoid writing the inode by logging any non-transactional changes
that are pending.  This needs to be done with synchronous
transactions, but it avoids seeking between the log and inode
clusters as we do now. We don't force the log if the inode is
pinned, though, so this differs from the fsync case.  For normal
sys_sync and unmount behaviour this is fine because we do a
synchronous log force in xfs_sync_data which is called from the
->sync_fs code.

It does however break the NFS synchronous export guarantees for now,
but work is under way to fix this at a higher level or for the
higher level to provide an additional flag in the writeback control
to tell us that a log force is needed.

Portions of this patch are based on work from Dave Chinner.

Signed-off-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
2010-02-09 11:43:49 +11:00
Christoph Hellwig
e8b217e753 xfs: remove invalid barrier optimization from xfs_fsync
We always need to flush the disk write cache and can't skip it just because
the no inode attributes have changed.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
2010-02-02 10:16:26 +11:00
Dave Chinner
20026d9201 xfs: kill the unused XFS_QMOPT_* flush flags V2
dquots are never flushed asynchronously. Remove the flag and the
async write support from the flush function. Make the default flush
a delwri flush to make the inode flush code, which leaves the
XFS_QMOPT_SYNC the only flag remaining.  Convert that to use
SYNC_WAIT instead, just like the inode flush code.

V2:
- just pass flush flags straight through

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-02-04 09:48:58 +11:00
Dave Chinner
7d6a7bde52 xfs: Use delay write promotion for dquot flushing
xfs_qm_dqflock_pushbuf_wait() does a very similar trick to item
pushing used to do to flush out delayed write dquot buffers. Change
it to use the new promotion method rather than an async flush.

Also, xfs_qm_dqflock_pushbuf_wait() can return without the flush lock
held, yet the callers make the assumption that after this call the
flush lock is held. Always return with the flush lock held.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-26 15:13:41 +11:00
Dave Chinner
089716aa14 xfs: Sort delayed write buffers before dispatch
Currently when the xfsbufd writes delayed write buffers, it pushes
them to disk in the order they come off the delayed write list. If
there are lots of buffers ѕpread widely over the disk, this results
in overwhelming the elevator sort queues in the block layer and we
end up losing the posibility of merging adjacent buffers to minimise
the number of IOs.

Use the new generic list_sort function to sort the delwri dispatch
queue before issue to ensure that the buffers are pushed in the most
friendly order possible to the lower layers.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-26 15:13:25 +11:00
Dave Chinner
d808f617ad xfs: Don't issue buffer IO direct from AIL push V2
All buffers logged into the AIL are marked as delayed write.
When the AIL needs to push the buffer out, it issues an async write of the
buffer. This means that IO patterns are dependent on the order of
buffers in the AIL.

Instead of flushing the buffer, promote the buffer in the delayed
write list so that the next time the xfsbufd is run the buffer will
be flushed by the xfsbufd. Return the state to the xfsaild that the
buffer was promoted so that the xfsaild knows that it needs to cause
the xfsbufd to run to flush the buffers that were promoted.

Using the xfsbufd for issuing the IO allows us to dispatch all
buffer IO from the one queue. This means that we can make much more
enlightened decisions on what order to flush buffers to disk as
we don't have multiple places issuing IO. Optimisations to xfsbufd
will be in a future patch.

Version 2
- kill XFS_ITEM_FLUSHING as it is now unused.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-02-02 10:13:42 +11:00
Dave Chinner
c854363e80 xfs: Use delayed write for inodes rather than async V2
We currently do background inode flush asynchronously, resulting in
inodes being written in whatever order the background writeback
issues them. Not only that, there are also blocking and non-blocking
asynchronous inode flushes, depending on where the flush comes from.

This patch completely removes asynchronous inode writeback. It
removes all the strange writeback modes and replaces them with
either a synchronous flush or a non-blocking delayed write flush.
That is, inode flushes will only issue IO directly if they are
synchronous, and background flushing may do nothing if the operation
would block (e.g. on a pinned inode or buffer lock).

Delayed write flushes will now result in the inode buffer sitting in
the delwri queue of the buffer cache to be flushed by either an AIL
push or by the xfsbufd timing out the buffer. This will allow
accumulation of dirty inode buffers in memory and allow optimisation
of inode cluster writeback at the xfsbufd level where we have much
greater queue depths than the block layer elevators. We will also
get adjacent inode cluster buffer IO merging for free when a later
patch in the series allows sorting of the delayed write buffers
before dispatch.

This effectively means that any inode that is written back by
background writeback will be seen as flush locked during AIL
pushing, and will result in the buffers being pushed from there.
This writeback path is currently non-optimal, but the next patch
in the series will fix that problem.

A side effect of this delayed write mechanism is that background
inode reclaim will no longer directly flush inodes, nor can it wait
on the flush lock. The result is that inode reclaim must leave the
inode in the reclaimable state until it is clean. Hence attempts to
reclaim a dirty inode in the background will simply skip the inode
until it is clean and this allows other mechanisms (i.e. xfsbufd) to
do more optimal writeback of the dirty buffers. As a result, the
inode reclaim code has been rewritten so that it no longer relies on
the ambiguous return values of xfs_iflush() to determine whether it
is safe to reclaim an inode.

Portions of this patch are derived from patches by Christoph
Hellwig.

Version 2:
- cleanup reclaim code as suggested by Christoph
- log background reclaim inode flush errors
- just pass sync flags to xfs_iflush

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-02-06 12:39:36 +11:00
Dave Chinner
777df5afdb xfs: Make inode reclaim states explicit
A.K.A.: don't rely on xfs_iflush() return value in reclaim

We have gradually been moving checks out of the reclaim code because
they are duplicated in xfs_iflush(). We've had a history of problems
in this area, and many of them stem from the overloading of the
return values from xfs_iflush() and interaction with inode flush
locking to determine if the inode is safe to reclaim.

With the desire to move to delayed write flushing of inodes and
non-blocking inode tree reclaim walks, the overloading of the
return value of xfs_iflush makes it very difficult to determine
the correct thing to do next.

This patch explicitly re-adds the checks to the inode reclaim code,
removing the reliance on the return value of xfs_iflush() to
determine what to do next. It also means that we can clearly
document all the inode states that reclaim must handle and hence
we can easily see that we handled all the necessary cases.

This also removes the need for the xfs_inode_clean() check in
xfs_iflush() as all callers now check this first (safely).

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-02-06 12:37:26 +11:00
Eric Sandeen
d5db0f97fb xfs: more reserved blocks fixups
This mangles the reserved blocks counts a little more.

1) add a helper function for the default reserved count
2) add helper functions to save/restore counts on ro/rw
3) save/restore reserved blocks on freeze/thaw
4) disallow changing reserved count while readonly

V2: changed field name to match Dave's changes

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-02-08 17:41:48 -06:00
Dave Chinner
388f1f0c34 xfs: turn off sign warnings
Because they cause warnings in static inline functions conditionally
compiled into XFS from the VFS (e.g. fsnotify).

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-26 15:10:15 +11:00
Dave Chinner
cbe132a8bd xfs: don't hold onto reserved blocks on remount,ro
If we hold onto reserved blocks when doing a remount,ro we end
up writing the blocks used count to disk that includes the reserved
blocks. Reserved blocks are not actually used, so this results in
the values in the superblock being incorrect.

Hence if we run xfs_check or xfs_repair -n while the filesystem is
mounted remount,ro we end up with an inconsistent filesystem being
reported. Also, running xfs_copy on the remount,ro filesystem will
result in an inconsistent image being generated.

To fix this, unreserve the blocks when doing the remount,ro, and
reserved them again on remount,rw. This way a remount,ro filesystem
will appear consistent on disk to all utilities.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-26 15:08:49 +11:00
Christoph Hellwig
9b00f30762 xfs: quota limit statvfs available blocks
A "df" run on an NFS client of an exported XFS file system reports
the wrong information for "available" blocks.  When a block quota is
enforced, the amount reported as free is limited by the quota, but
the amount reported available is not (and should be).

Reported-by: Guk-Bong, Kwon <gbkwon@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-21 16:34:23 -06:00
Christoph Hellwig
bdfb04301f xfs: replace KM_LARGE with explicit vmalloc use
We use the KM_LARGE flag to make kmem_alloc and friends use vmalloc
if necessary.  As we only need this for a few boot/mount time
allocations just switch to explicit vmalloc calls there.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-21 13:44:56 -06:00
Christoph Hellwig
a14a348bff xfs: cleanup up xfs_log_force calling conventions
Remove the XFS_LOG_FORCE argument which was always set, and the
XFS_LOG_URGE define, which was never used.

Split xfs_log_force into a two helpers - xfs_log_force which forces
the whole log, and xfs_log_force_lsn which forces up to the
specified LSN.  The underlying implementations already were entirely
separate, as were the users.

Also re-indent the new _xfs_log_force/_xfs_log_force which
previously had a weird coding style.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-21 13:44:49 -06:00
Christoph Hellwig
4139b3b337 xfs: kill XLOG_VEC_SET_TYPE
This macro only obsfucates the log item type assignments, so kill it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-21 13:44:43 -06:00
Christoph Hellwig
0cadda1c5f xfs: remove duplicate buffer flags
Currently we define aliases for the buffer flags in various
namespaces, which only adds confusion.  Remove all but the XBF_
flags to clean this up a bit.

Note that we still abuse XFS_B_ASYNC/XBF_ASYNC for some non-buffer
uses, but I'll clean that up later.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-21 13:44:36 -06:00
Christoph Hellwig
a210c1aa7f xfs: implement quota warnings via netlink
Wire up quota_send_warning to send quota warnings over netlink.
This is used by various desktops to show user quota warnings.

Tested by running the quota_nld daemon while running the xfstest
quota tests and observing the warnings.  I'll see how I can get a
more formal testcase for it written.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-21 13:44:28 -06:00
Christoph Hellwig
4d1f88d75b xfs: clean up error handling in xfs_trans_dqresv
Move the error code selection after the goto label and fold the
xfs_quota_error helper into it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-21 13:44:22 -06:00
Christoph Hellwig
512dd1abd9 xfs: kill XFS_QMOPT_ASYNC
The option is unused and one of the few remaining users of
xfs_bawrite, so let's get rid of it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-21 13:44:10 -06:00
Dave Chinner
587aa0feb7 xfs: rearrange xfs_mod_sb() to avoid array subscript warning
gcc warns of an array subscript out of bounds in xfs_mod_sb().
The code is written in such a way that if the array subscript is
out of bounds, then it will assert fail. Rearrange the code to
avoid the bounds check warning.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-20 12:04:53 +11:00
Dave Chinner
f0a0eaa8da xfs: suppress spurious uninitialised var warning in xfs_bmapi()
Initialise the xfs_bmalloca_t structure to zero to avoid uninitialised
variable warnings. This is done by zeroing the arg structure rather than
using the uninitialised_var() trick so we know for certain that the
structure is correctly initialised as xfs_bmapi is a very complex
function and it is difficult to prove warnings are spurious.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-20 10:50:06 +11:00
Dave Chinner
58c75cfb51 xfs: make compile warn about char sign mismatches again
The -fno-unsigned-char directive has no effect anymore as the
XFs build is clean. However, the kernel build hides pointer sign
differences so turn that back on so that we can clean up all the
mismatches prior to a userspace code resync.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-20 10:49:18 +11:00
Dave Chinner
4a24cb7140 xfs: clean up sign warnings in dir2 code
We are now consistently using unsigned char strings for names
so fix up the remaining warnings in the dir2 code to complete
the cleanup.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-20 10:48:05 +11:00
Dave Chinner
a9273ca5c6 xfs: convert attr to use unsigned names
To be consistent with the directory code, the attr code should use
unsigned names. Convert the names from the vfs at the highest level
to unsigned, and ænsure they are consistenly used as unsigned down
to disk.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-20 10:47:48 +11:00
Dave Chinner
b9c4864957 xfs: xfs_buf_iomove() doesn't care about signedness
xfs_buf_iomove() uses xfs_caddr_t as it's parameter types, but it doesn't
care about the signedness of the variables as it is just copying the
data. Change the prototype to use void * so that we don't get sign
warnings at call sites.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-20 10:47:39 +11:00
Dave Chinner
a3380ae39f xfs: make xfs_dir_cilookup_result use unsigned char
For consistency with the result of the code.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-20 10:47:25 +11:00
Dave Chinner
2bc754213d xfs: convert dirnameops to unsigned char names
To be consistent across the codebase, convert the dirnameops to pass
the directory names by unsigned char strings.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-20 10:47:17 +11:00
Dave Chinner
046ea75313 xfs: convert DM ops to use unsigned char names
dmops uses a signed char for it's namespace event. To be consistent
with the rest of the code, convert them to unsigned char for the
namespace string.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-20 10:47:08 +11:00
Dave Chinner
e2bcd936eb xfs: directory names are unsigned
Convert the struct xfs_name to use unsigned chars for the name
strings to match both what is stored on disk (__uint8_t) and what
the VFS expects (unsigned char).

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-20 10:44:58 +11:00
Christoph Hellwig
4e23471a3f xfs: move more buffer helpers into xfs_buf.c
Move xfsbdstrat and xfs_bdstrat_cb from xfs_lrw.c and xfs_bioerror
and xfs_bioerror_relse from xfs_rw.c into xfs_buf.c.  This also
means xfs_bioerror and xfs_bioerror_relse can be marked static now.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:35:17 -06:00
Christoph Hellwig
64e0bc7d2a xfs: clean up xfs_bwrite
Fold XFS_bwrite into it's only caller, xfs_bwrite and move it into
xfs_buf.c instead of leaving it as a fairly large inline function.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:35:07 -06:00
Christoph Hellwig
873ff5501d xfs: clean up log buffer writes
Don't bother using XFS_bwrite as it doesn't provide much code for
our use case.  Instead opencode it and fold xlog_bdstrat_cb into the
new xlog_bdstrat helper.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:34:54 -06:00
Dave Chinner
e57336ff7f xfs: embed the pagb_list array in the perag structure
Now that the perag structure is allocated memory rather than held in
an array, we don't need to have the busy extent array external to
the structure. Embed it into the perag structure to avoid needing an
extra allocation when setting up.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:34:39 -06:00
Dave Chinner
8b26c5825e xfs: handle ENOMEM correctly during initialisation of perag structures
Add proper error handling in case an error occurs while initializing
new perag structures for a mount point.  The mount structure is
restored to its previous state by deleting and freeing any perag
structures added during the call.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:34:30 -06:00
Dave Chinner
b657fc82a3 xfs: Kill filestreams cache flush
The filestreams cache flush is not needed in the sync code as it
does not affect data writeback, and it is now not used by the growfs
code, either, so kill it.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:34:22 -06:00
Dave Chinner
0fa800fbd5 xfs: Add trace points for per-ag refcount debugging.
Uninline xfs_perag_{get,put} so that tracepoints can be inserted
into them to speed debugging of reference count problems.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:34:12 -06:00
Dave Chinner
aed3bb90ab xfs: Reference count per-ag structures
Reference count the per-ag structures to ensure that we keep get/put
pairs balanced. Assert that the reference counts are zero at unmount
time to catch leaks. In future, reference counts will enable us to
safely remove perag structures by allowing us to detect when they
are no longer in use.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:34:04 -06:00
Dave Chinner
1c1c6ebcf5 xfs: Replace per-ag array with a radix tree
The use of an array for the per-ag structures requires reallocation
of the array when growing the filesystem. This requires locking
access to the array to avoid use after free situations, and the
locking is difficult to get right. To avoid needing to reallocate an
array, change the per-ag structures to an allocated object per ag
and index them using a tree structure.

The AGs are always densely indexed (hence the use of an array), but
the number supported is 2^32 and lookups tend to be random and hence
indexing needs to scale. A simple choice is a radix tree - it works
well with this sort of index.  This change also removes another
large contiguous allocation from the mount/growfs path in XFS.

The growing process now needs to change to only initialise the new
AGs required for the extra space, and as such only needs to
exclusively lock the tree for inserts. The rest of the code only
needs to lock the tree while doing lookups, and hence this will
remove all the deadlocks that currently occur on the m_perag_lock as
it is now an innermost lock. The lock is also changed to a spinlock
from a read/write lock as the hold time is now extremely short.

To complete the picture, the per-ag structures will need to be
reference counted to ensure that we don't free/modify them while
they are still in use.  This will be done in subsequent patch.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:33:52 -06:00
Dave Chinner
44b56e0a1a xfs: convert remaining direct references to m_perag
Convert the remaining direct lookups of the per ag structures to use
get/put accesses. Ensure that the loops across AGs and prior users
of the interface balance gets and puts correctly.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:33:39 -06:00
Dave Chinner
4196ac08c0 xfs: Convert filestreams code to use per-ag get/put routines
Use xfs_perag_get() and xfs_perag_put() in the filestreams code.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:33:22 -06:00
Dave Chinner
a862e0fdcb xfs: Don't directly reference m_perag in allocation code
Start abstracting the perag references so that the indexing of the
structures is not directly coded into all the places that uses the
perag structures. This will allow us to separate the use of the
perag structure and the way it is indexed and hence avoid the known
deadlocks related to growing a busy filesystem.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:33:12 -06:00
Dave Chinner
5017e97d52 xfs: rename xfs_get_perag
xfs_get_perag is really getting the perag that an inode belongs to
based on it's inode number. Convert the use of this function to just
get the perag from a provided ag number.  Use this new function to
obtain the per-ag structure when traversing the per AG inode trees
for sync and reclaim.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:33:02 -06:00
Dave Chinner
c9c129714e xfs: Don't wake xfsbufd when idle
The xfsbufd wakes every xfsbufd_centisecs (once per second by
default) for each filesystem even when the filesystem is idle.  If
the xfsbufd has nothing to do, put it into a long term sleep and
only wake it up when there is work pending (i.e. dirty buffers to
flush soon). This will make laptop power misers happy.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:32:54 -06:00