All of the work xfssyncd does is background functionality. There is
no need for a thread per filesystem to do this work - it can al be
managed by a global workqueue now they manage concurrency
effectively.
Introduce a new gglobal xfssyncd workqueue, and convert the periodic
work to use this new functionality. To do this, use a delayed work
construct to schedule the next running of the periodic sync work
for the filesystem. When the sync work is complete, queue a new
delayed work for the next running of the sync work.
For laptop mode, we wait on completion for the sync works, so ensure
that the sync work queuing interface can flush and wait for work to
complete to enable the work queue infrastructure to replace the
current sequence number and wakeup that is used.
Because the sync work does non-trivial amounts of work, mark the
new work queue as CPU intensive.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
With the reclaim code separated from the generic walking code, it is
simple to implement batched lookups for the generic walk code.
Separate out the inode validation from the execute operations and
modify the tree lookups to get a batch of inodes at a time.
Reclaim operations will be optimised separately.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
The reclaim walk requires different locking and has a slightly
different walk algorithm, so separate it out so that it can be
optimised separately.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
On the final put of a superblock the VFS already calls sync_filesystem
for us to write out all data and wait for it. No need to start another
asynchronous writeback inside ->put_super.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Now the shrinker passes us a context, wire up a shrinker context per
filesystem. This allows us to remove the global mount list and the
locking problems that introduced. It also means that a shrinker call
does not need to traverse clean filesystems before finding a
filesystem with reclaimable inodes. This significantly reduces
scanning overhead when lots of filesystems are present.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
On low memory boxes or those with highmem, kernel can OOM before the
background reclaims inodes via xfssyncd. Add a shrinker to run inode
reclaim so that it inode reclaim is expedited when memory is low.
This is more complex than it needs to be because the VM folk don't
want a context added to the shrinker infrastructure. Hence we need
to add a global list of XFS mount structures so the shrinker can
traverse them.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Just minor housekeeping, a lot more functions can be trivially made
static; others could if we reordered things a bit...
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Alex Elder <aelder@sgi.com>
Make the inode tree reclaim walk exclusive to avoid races with
concurrent sync walkers and lookups. This is a version of a patch
posted by Christoph Hellwig that avoids all the code duplication.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Currently the reclaim code for the case where we don't reclaim the
final reclaim is overly complicated. We know that the inode is clean
but instead of just directly reclaiming the clean inode we go through
the whole process of marking the inode reclaimable just to directly
reclaim it from the calling context. Besides being overly complicated
this introduces a race where iget could recycle an inode between
marked reclaimable and actually being reclaimed leading to panics.
This patch gets rid of the existing reclaim path, and replaces it with
a simple call to xfs_ireclaim if the inode was clean. While we're at
it we also use the slightly more lax xfs_inode_clean check we'd use
later to determine if we need to flush the inode here.
Finally get rid of xfs_reclaim function and place the remaining small
bits of reclaim code directly into xfs_fs_destroy_inode.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Patrick Schreurs <patrick@news-service.com>
Reported-by: Tommy van Leeuwen <tommy@news-service.com>
Tested-by: Patrick Schreurs <patrick@news-service.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
A lot more functions could be made static, but they need
forward declarations; this does some easy ones, and also
found a few unused functions in the process.
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
The locking in xfs_iget_cache_hit currently has numerous problems:
- we clear the reclaim tag without i_flags_lock which protects
modifications to it
- we call inode_init_always which can sleep with pag_ici_lock
held (this is oss.sgi.com BZ #819)
- we acquire and drop i_flags_lock a lot and thus provide no
consistency between the various flags we set/clear under it
This patch fixes all that with a major revamp of the locking in
the function. The new version acquires i_flags_lock early and
only drops it once we need to call into inode_init_always or before
calling xfs_ilock.
This patch fixes a bug seen in the wild where we race modifying the
reclaim tag.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
SYNC_BDFLUSH is a leftover from IRIX and rather misnamed for todays
code. Make xfs_sync_fsdata and xfs_dq_sync use the SYNC_TRYLOCK flag
for not blocking on logs just as the inode sync code already does.
For xfs_sync_fsdata it's a trivial 1:1 replacement, but for xfs_qm_sync
I use the opportunity to decouple the non-blocking lock case from the
different flushing modes, similar to the inode sync code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
We want to wait for all I/O to finish when we do data integrity syncs. So
there is no reason to keep SYNC_WAIT separate from SYNC_IOWAIT. This
causes a little change in behaviour for the ENOSPC flushing code which now
does a second submission and wait of buffered I/O, but that should finish
ASAP as we already did an asynchronous writeout earlier.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
xfs_sync_inodes is used to write back either file data or inode metadata.
In general we always do these separately, except for one fishy case in
xfs_fs_put_super that does both. So separate xfs_sync_inodes into
separate xfs_sync_data and xfs_sync_attr functions. In xfs_fs_put_super
we first call the data sync and then the attr sync as that was the previous
order. The moved log force in that path doesn't make a difference because
we will force the log again as part of the real unmount process.
The filesystem readonly checks are not performed by the new function but
instead moved into the callers, given that most callers alredy have it
further up in the stack. Also add debug checks that we do not pass in
incorrect flags in the new xfs_sync_data and xfs_sync_attr function and
fix the one place that did pass in a wrong flag.
Also remove a comment mentioning xfs_sync_inodes that has been incorrect
for a while because we always take either the iolock or ilock in the
sync path these days.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
Use xfs_inode_ag_iterator instead of opencoding the inode walk in the
quota code. Mark xfs_inode_ag_iterator and xfs_sync_inode_valid non-static
to allow using them from the quota code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
The noblock parameter of xfs_reclaim_inodes is only ever set to zero. Remove
it and all the conditional code that is never executed.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
xfs_flush_inodes() currently uses a magic timeout to wait for
some inodes to be flushed before returning. This isn't
really reliable but used to be the best that could be done
due to deadlock potential of waiting for the entire flush.
Now the inode flush is safe to execute while we hold page
and inode locks, we can wait for all the inodes to flush
synchronously. Convert the wait mechanism to a completion
to do this efficiently. This should remove all remaining
spurious ENOSPC errors from the delayed allocation reservation
path.
This is extracted almost line for line from a larger patch
from Mikulas Patocka.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
When we are writing to a single file and hit ENOSPC, we trigger a background
flush of the inode and try again. Because we hold page locks and the iolock,
the flush won't proceed until after we release these locks. This occurs once
we've given up and ENOSPC has been reported. Hence if this one is the only
dirty inode in the system, we'll get an ENOSPC prematurely.
To fix this, remove the async flush from the allocation routines and move
it to the top of the write path where we can do a synchronous flush
and retry the write again. Only retry once as a second ENOSPC indicates
that we really are ENOSPC.
This avoids a page cache deadlock when trying to do this flush synchronously
in the allocation layer that was identified by Mikulas Patocka.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Currently xfs_device_flush calls sync_blockdev() which is
a no-op for XFS as all it's metadata is held in a different
address to the one sync_blockdev() works on.
Call xfs_sync_inodes() instead to flush all the delayed
allocation blocks out. To do this as efficiently as possible,
do it via two passes - one to do an async flush of all the
dirty blocks and a second to wait for all the IO to complete.
This requires some modification to the xfs-sync_inodes_ag()
flush code to do efficiently.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Currently we call from the nicely abstracted linux quotaops into a ugly
multiplexer just to split the calls out at the same boundary again.
Rewrite the quota ops handling to remove that obfucation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Prepare for removing the deleted inode list by marking inodes for reclaim
in the inode radix trees so that we can use the radix trees to find
reclaimable inodes.
SGI-PV: 988142
SGI-Modid: xfs-linux-melb:xfs-kern:32331a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
The function names xfs_finish_reclaim and xfs_finish_reclaim_all are not
very descriptive of what they are reclaiming. Rename to
xfs_reclaim_inode[s] to match the xfs_sync_inodes() function.
SGI-PV: 988142
SGI-Modid: xfs-linux-melb:xfs-kern:32330a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Background inode reclaim is run by the xfssyncd. Move the reclaim worker
functions to be close to the sync code as the are very similar in
structure and are both run from the same background thread.
SGI-PV: 988142
SGI-Modid: xfs-linux-melb:xfs-kern:32329a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
With all the other filesystem sync code it in xfs_sync.c including the
data quiesce code, it makes sense to move the remaining quiesce code to
the same place.
SGI-PV: 988140
SGI-Modid: xfs-linux-melb:xfs-kern:32312a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
There are no more callers to xfs_sync() now, so remove the function
altogther.
SGI-PV: 988140
SGI-Modid: xfs-linux-melb:xfs-kern:32311a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
SYNC_CLOSE is only ever used and checked in conjunction with SYNC_WAIT,
and this only done in one spot. The only thing this does is make
XFS_bflush() calls to the data buftargs.
This will happen very shortly afterwards the xfs_sync() call anyway in the
unmount path via the xfs_close_devices(), so this code is redundant and
can be removed. That only user of SYNC_CLOSE is now gone, so kill the flag
completely.
SGI-PV: 988140
SGI-Modid: xfs-linux-melb:xfs-kern:32310a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Continue to de-multiplex xfs_sync be replacing all SYNC_DELWRI callers
with direct calls functions that do the work. Isolate the data quiesce
case to a function in xfs_sync.c. Isolate the FSDATA case with explicit
calls to xfs_sync_fsdata().
Version 2: o Push delwri related log forces into xfs_sync_inodes().
SGI-PV: 988140
SGI-Modid: xfs-linux-melb:xfs-kern:32309a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Continue to de-multiplex xfs_sync be replacing all SYNC_ATTR callers with
direct calls xfs_sync_inodes(). Add an assert into xfs_sync() to ensure we
caught all the SYNC_ATTR callers.
SGI-PV: 988140
SGI-Modid: xfs-linux-melb:xfs-kern:32308a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Kill the unused arg in xfs_syncsub() and xfs_sync_inodes(). For callers of
xfs_syncsub() that only want to flush inodes, replace xfs_syncsub() with
direct calls to xfs_sync_inodes() as that is all that is being done with
the specific flags being passed in.
SGI-PV: 988140
SGI-Modid: xfs-linux-melb:xfs-kern:32305a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Move all the xfssyncd code to the new xfs_sync.c file. This places it
closer to the actual code that it interacts with, rather than just being
associated with high level VFS code.
SGI-PV: 988139
SGI-Modid: xfs-linux-melb:xfs-kern:32283a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
The sync code in XFS is spread around several files. While it used to make
sense to have such a distribution, the code is about to be cleaned up and
so centralising it in one spot as the first step makes sense.
SGI-PV: 988139
SGI-Modid: xfs-linux-melb:xfs-kern:32282a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
