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path: root/fs/xfs/xfs_iget.c
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2012-07-29xfs: remove iolock lock classesChristoph Hellwig
Content-Disposition: inline; filename=xfs-remove-iolock-classes Now that we never take the iolock during inode reclaim we don't need to play games with lock classes. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Rich Johnston <rjohnston@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-21xfs: fix memory reclaim deadlock on agi bufferPeter Watkins
Note xfs_iget can be called while holding a locked agi buffer. If it goes into memory reclaim then inode teardown may try to lock the same buffer. Prevent the deadlock by calling radix_tree_preload with GFP_NOFS. Signed-off-by: Peter Watkins <treestem@gmail.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-05-14xfs: clean up xfs_bit.h includesDave Chinner
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>
2012-05-14xfs: remove log item from AIL in xfs_iflush after a shutdownChristoph Hellwig
If a filesystem has been forced shutdown we are never going to write inodes to disk, which means the inode items will stay in the AIL until we free the inode. Currently that is not a problem, but a pending change requires us to empty the AIL before shutting down the filesystem. In that case leaving the inode in the AIL is lethal. Make sure to remove the log item from the AIL to allow emptying the AIL on shutdown filesystems. 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>
2012-03-26xfs: don't cache inodes read through bulkstatDave Chinner
When we read inodes via bulkstat, we generally only read them once and then throw them away - they never get used again. If we retain them in cache, then it simply causes the working set of inodes and other cached items to be reclaimed just so the inode cache can grow. Avoid this problem by marking inodes read by bulkstat not to be cached and check this flag in .drop_inode to determine whether the inode should be added to the VFS LRU or not. If the inode lookup hits an already cached inode, then don't set the flag. If the inode lookup hits an inode marked with no cache flag, remove the flag and allow it to be cached once the current reference goes away. Inodes marked as not cached will get cleaned up by the background inode reclaim or via memory pressure, so they will still generate some short term cache pressure. They will, however, be reclaimed much sooner and in preference to cache hot inodes. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-03-15xfs: fix inode lookup raceDave Chinner
When we get concurrent lookups of the same inode that is not in the per-AG inode cache, there is a race condition that triggers warnings in unlock_new_inode() indicating that we are initialising an inode that isn't in a the correct state for a new inode. When we do an inode lookup via a file handle or a bulkstat, we don't serialise lookups at a higher level through the dentry cache (i.e. pathless lookup), and so we can get concurrent lookups of the same inode. The race condition is between the insertion of the inode into the cache in the case of a cache miss and a concurrently lookup: Thread 1 Thread 2 xfs_iget() xfs_iget_cache_miss() xfs_iread() lock radix tree radix_tree_insert() rcu_read_lock radix_tree_lookup lock inode flags XFS_INEW not set igrab() unlock inode flags rcu_read_unlock use uninitialised inode ..... lock inode flags set XFS_INEW unlock inode flags unlock radix tree xfs_setup_inode() inode flags = I_NEW unlock_new_inode() WARNING as inode flags != I_NEW This can lead to inode corruption, inode list corruption, etc, and is generally a bad thing to occur. Fix this by setting XFS_INEW before inserting the inode into the radix tree. This will ensure any concurrent lookup will find the new inode with XFS_INEW set and that forces the lookup to wait until the XFS_INEW flag is removed before allowing the lookup to succeed. cc: <stable@vger.kernel.org> # for 3.0.x, 3.2.x Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-03-13xfs: log timestamp updatesChristoph Hellwig
Timestamps on regular files are the last metadata that XFS does not update transactionally. Now that we use the delaylog mode exclusively and made the log scode scale extremly well there is no need to bypass that code for timestamp updates. Logging all updates allows to drop a lot of code, and will allow for further performance improvements later on. Note that this patch drops optimized handling of fdatasync - it will be added back in a separate commit. 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>
2012-02-25xfs: only take the ILOCK in xfs_reclaim_inode()Alex Elder
At the end of xfs_reclaim_inode(), the inode is locked in order to we wait for a possible concurrent lookup to complete before the inode is freed. This synchronization step was taking both the ILOCK and the IOLOCK, but the latter was causing lockdep to produce reports of the possibility of deadlock. It turns out that there's no need to acquire the IOLOCK at this point anyway. It may have been required in some earlier version of the code, but there should be no need to take the IOLOCK in xfs_iget(), so there's no (longer) any need to get it here for synchronization. Add an assertion in xfs_iget() as a reminder of this assumption. Dave Chinner diagnosed this on IRC, and Christoph Hellwig suggested no longer including the IOLOCK. I just put together the patch. Signed-off-by: Alex Elder <elder@dreamhost.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-02-22xfs: remove xfs_trans_unlocked_itemChristoph Hellwig
There is no reason to wake up log space waiters when unlocking inodes or dquots, and the commit log has no explanation for this function either. Given that we now have exact log space wakeups everywhere we can assume the reason for this function was to paper over log space races in earlier XFS versions. Reviewed-by: Mark Tinguely <tinguely@sgi.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-01-17xfs: remove the i_new_size field in struct xfs_inodeChristoph Hellwig
Now that we use the VFS i_size field throughout XFS there is no need for the i_new_size field any more given that the VFS i_size field gets updated in ->write_end before unlocking the page, and thus is always uptodate when writeback could see a page. Removing i_new_size also has the advantage that we will never have to trim back di_size during a failed buffered write, given that it never gets updated past i_size. Note that currently the generic direct I/O code only updates i_size after calling our end_io handler, which requires a small workaround to make sure di_size actually makes it to disk. I hope to fix this properly in the generic code. A downside is that we lose the support for parallel non-overlapping O_DIRECT appending writes that recently was added. I don't think keeping the complex and fragile i_new_size infrastructure for this is a good tradeoff - if we really care about parallel appending writers we should investigate turning the iolock into a range lock, which would also allow for parallel non-overlapping buffered writers. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-01-17xfs: remove the i_size field in struct xfs_inodeChristoph Hellwig
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>
2012-01-17xfs: replace i_flock with a sleeping bitlockChristoph Hellwig
We almost never block on i_flock, the exception is synchronous inode flushing. Instead of bloating the inode with a 16/24-byte completion that we abuse as a semaphore just implement it as a bitlock that uses a bit waitqueue for the rare sleeping path. This primarily is a tradeoff between a much smaller inode and a faster non-blocking path vs faster wakeups, and we are much better off with the former. A small downside is that we will lose lockdep checking for i_flock, but given that it's always taken inside the ilock that should be acceptable. Note that for example the inode writeback locking is implemented in a very similar way. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Alex Elder <aelder@sgi.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-01-17xfs: remove the if_ext_max field in struct xfs_iforkChristoph Hellwig
We spent a lot of effort to maintain this field, but it always equals to the fork size divided by the constant size of an extent. The prime use of it is to assert that the two stay in sync. Just divide the fork size by the extent size in the few places that we actually use it and remove the overhead of maintaining it. Also introduce a few helpers to consolidate the places where we actually care about the value. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2012-01-03vfs: fix the stupidity with i_dentry in inode destructorsAl Viro
Seeing that just about every destructor got that INIT_LIST_HEAD() copied into it, there is no point whatsoever keeping this INIT_LIST_HEAD in inode_init_once(); the cost of taking it into inode_init_always() will be negligible for pipes and sockets and negative for everything else. Not to mention the removal of boilerplate code from ->destroy_inode() instances... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-10-11xfs: remove i_iocountChristoph Hellwig
We now have an i_dio_count filed and surrounding infrastructure to wait for direct I/O completion instead of i_icount, and we have never needed to iocount waits for buffered I/O given that we only set the page uptodate after finishing all required work. Thus remove i_iocount, and replace the actually needed waits with calls to inode_dio_wait. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
2011-07-13xfs: remove leftovers of the old btree tracing codeChristoph Hellwig
Remove various bits left over from the old kdb-only btree tracing code, but leave the actual trace point stubs in place to ease adding new event based btree tracing. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Alex Elder <aelder@sgi.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2011-06-23xfs: reset inode per-lifetime state when recycling itDave Chinner
XFS inodes has several per-lifetime state fields that determine the behaviour of the inode. These state fields are not all reset when an inode is reused from the reclaimable state. This can lead to unexpected behaviour of the new inode such as speculative preallocation not being truncated away in the expected manner for local files until the inode is subsequently truncated, freed or cycles out of the cache. It can also lead to an inode being considered to be a filestream inode or having been truncated when that is not the case. Rework the reinitialisation of the inode when it is recycled to ensure that it is pristine before it is reused. While there, also fix the resetting of state flags in the recycling error paths so the inode does not become unreclaimable. Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Alex Elder <aelder@sgi.com>
2011-01-10Merge branch 'master' into for-linus-mergedAlex Elder
This merge pulls the XFS master branch into the latest Linus master. This results in a merge conflict whose best fix is not obvious. I manually fixed the conflict, in "fs/xfs/xfs_iget.c". Dave Chinner had done work that resulted in RCU freeing of inodes separate from what Nick Piggin had done, and their results differed slightly in xfs_inode_free(). The fix updates Nick's call_rcu() with the use of VFS_I(), while incorporating needed updates to some XFS inode fields implemented in Dave's series. Dave's RCU callback function has also been removed. Signed-off-by: Alex Elder <aelder@sgi.com>
2011-01-07fs: icache RCU free inodesNick Piggin
RCU free the struct inode. This will allow: - Subsequent store-free path walking patch. The inode must be consulted for permissions when walking, so an RCU inode reference is a must. - sb_inode_list_lock to be moved inside i_lock because sb list walkers who want to take i_lock no longer need to take sb_inode_list_lock to walk the list in the first place. This will simplify and optimize locking. - Could remove some nested trylock loops in dcache code - Could potentially simplify things a bit in VM land. Do not need to take the page lock to follow page->mapping. The downsides of this is the performance cost of using RCU. In a simple creat/unlink microbenchmark, performance drops by about 10% due to inability to reuse cache-hot slab objects. As iterations increase and RCU freeing starts kicking over, this increases to about 20%. In cases where inode lifetimes are longer (ie. many inodes may be allocated during the average life span of a single inode), a lot of this cache reuse is not applicable, so the regression caused by this patch is smaller. The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU, however this adds some complexity to list walking and store-free path walking, so I prefer to implement this at a later date, if it is shown to be a win in real situations. I haven't found a regression in any non-micro benchmark so I doubt it will be a problem. Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2010-12-16xfs: convert pag_ici_lock to a spin lockDave Chinner
now that we are using RCU protection for the inode cache lookups, the lock is only needed on the modification side. Hence it is not necessary for the lock to be a rwlock as there are no read side holders anymore. Convert it to a spin lock to reflect it's exclusive nature. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Alex Elder <aelder@sgi.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-17xfs: convert inode cache lookups to use RCU lockingDave Chinner
With delayed logging greatly increasing the sustained parallelism of inode operations, the inode cache locking is showing significant read vs write contention when inode reclaim runs at the same time as lookups. There is also a lot more write lock acquistions than there are read locks (4:1 ratio) so the read locking is not really buying us much in the way of parallelism. To avoid the read vs write contention, change the cache to use RCU locking on the read side. To avoid needing to RCU free every single inode, use the built in slab RCU freeing mechanism. This requires us to be able to detect lookups of freed inodes, so enѕure that ever freed inode has an inode number of zero and the XFS_IRECLAIM flag set. We already check the XFS_IRECLAIM flag in cache hit lookup path, but also add a check for a zero inode number as well. We canthen convert all the read locking lockups to use RCU read side locking and hence remove all read side locking. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Alex Elder <aelder@sgi.com>
2010-12-16xfs: rcu free inodesDave Chinner
Introduce RCU freeing of XFS inodes so that we can convert lookup traversals to use rcu_read_lock() protection. This patch only introduces the RCU freeing to minimise the potential conflicts with mainline if this is merged into mainline via a VFS patchset. It abuses the i_dentry list for the RCU callback structure because the VFS patches make this a union so it is safe to use like this and simplifies and merge issues. This patch uses basic RCU freeing rather than SLAB_DESTROY_BY_RCU. The later lookup patches need the same "found free inode" protection regardless of the RCU freeing method used, so once again the RCU freeing method can be dealt with apprpriately at merge time without affecting any other code. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2010-12-23xfs: provide a inode iolock lockdep classDave Chinner
The XFS iolock needs to be re-initialised to a new lock class before it enters reclaim to prevent lockdep false positives. Unfortunately, this is not sufficient protection as inodes in the XFS_IRECLAIMABLE state can be recycled and not re-initialised before being reused. We need to re-initialise the lock state when transfering out of XFS_IRECLAIMABLE state to XFS_INEW, but we need to keep the same class as if the inode was just allocated. Hence we need a specific lockdep class variable for the iolock so that both initialisations use the same class. While there, add a specific class for inodes in the reclaim state so that it is easy to tell from lockdep reports what state the inode was in that generated the report. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-10-18xfs: fix bogus m_maxagi check in xfs_igetChristoph Hellwig
These days inode64 should only control which AGs we allocate new inodes from, while we still try to support reading all existing inodes. To make this actually work the check ontop of xfs_iget needs to be relaxed to allow inodes in all allocation groups instead of just those that we allow allocating inodes from. Note that we can't simply remove the check - it prevents us from accessing invalid data when fed invalid inode numbers from NFS or bulkstat. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2010-07-26xfs: fix gcc 4.6 set but not read and unused statement warningsChristoph Hellwig
[hch: dropped a few hunks that need structural changes instead] Signed-off-by: Andi Kleen <ak@linux.intel.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2010-07-26xfs: simplify and remove xfs_ireclaimDave Chinner
xfs_ireclaim has to get and put te pag structure because it is only called with the inode to reclaim. The one caller of this function already has a reference on the pag and a pointer to is, so move the radix tree delete to the caller and remove xfs_ireclaim completely. This avoids a xfs_perag_get/put on every inode being reclaimed. The overhead was noticed in a bug report at: https://bugzilla.kernel.org/show_bug.cgi?id=16348 Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Alex Elder <aelder@sgi.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2010-07-26xfs: remove xfs_iputChristoph Hellwig
xfs_iput is just a small wrapper for xfs_iunlock + IRELE. Having this out of line wrapper means the trace events in those two can't track their caller properly. So just remove the wrapper and opencode the unlock + rele in the few callers. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2010-07-26xfs: remove xfs_iput_newChristoph Hellwig
We never get an i_mode of 0 or a locked VFS inode until we pass in the XFS_IGET_CREATE flag to xfs_iget, which makes xfs_iput_new equivalent to xfs_iput for the only caller. In addition to that xfs_nfs_get_inode does not even need to lock the inode given that the generation never changes for a life inode, so just pass a 0 lock_flags to xfs_iget and release the inode using IRELE in the error path. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2010-07-26xfs: some iget tracing cleanups / fixesChristoph Hellwig
The xfs_iget_alloc/found tracepoints are a bit misnamed and misplaced. Rename them to xfs_iget_hit/xfs_iget_miss and move them to the beggining of the xfs_iget_cache_hit/miss functions. Add a new xfs_iget_reclaim_fail tracepoint for the case where we fail to re-initialize a VFS inode, and add a second instance of the xfs_iget_skip tracepoint for the case of a failed igrab() call. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2010-07-26xfs: remove unneeded #include statementsChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <david@fromorbit.com>
2010-07-26xfs: drop dmapi hooksChristoph Hellwig
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>
2010-06-24xfs: remove block number from inode lookup codeDave Chinner
The block number comes from bulkstat based inode lookups to shortcut the mapping calculations. We ar enot able to trust anything from bulkstat, so drop the block number as well so that the correct lookups and mappings are always done. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-06-03xfs: improve xfs_isilockedChristoph Hellwig
Use rwsem_is_locked to make the assertations for shared locks work. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2010-05-28xfs: fix access to upper inodes without inode64Christoph Hellwig
If a filesystem is mounted without the inode64 mount option we should still be able to access inodes not fitting into 32 bits, just not created new ones. For this to work we need to make sure the inode cache radix tree is initialized for all allocation groups, not just those we plan to allocate inodes from. This patch makes sure we initialize the inode cache radix tree for all allocation groups, and also cleans xfs_initialize_perag up a bit to separate the inode32 logical from the general perag structure setup. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-01xfs: fix locking for inode cache radix tree tag updatesChristoph Hellwig
The radix-tree code requires it's users to serialize tag updates against other updates to the tree. While XFS protects tag updates against each other it does not serialize them against updates of the tree contents, which can lead to tag corruption. Fix the inode cache to always take pag_ici_lock in exclusive mode when updating radix tree tags. Signed-off-by: Christoph Hellwig <hch@lst.de> Reported-by: Patrick Schreurs <patrick@news-service.com> Tested-by: Patrick Schreurs <patrick@news-service.com> Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15xfs: rename xfs_get_peragDave Chinner
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>
2010-01-15xfs: Remove inode iolock held check during allocationDave Chinner
lockdep complains about a the lock not being initialised as we do an ASSERT based check that the lock is not held before we initialise it to catch inodes freed with the lock held. lockdep does this check for us in the lock initialisation code, so remove the ASSERT to stop the lockdep warning. Signed-off-by: Dave Chinner <david@fromorbit.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-17kill I_LOCKChristoph Hellwig
After I_SYNC was split from I_LOCK the leftover is always used together with I_NEW and thus superflous. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-16xfs: check for not fully initialized inodes in xfs_ireclaimChristoph Hellwig
Add an assert for inodes not added to the inode cache in xfs_ireclaim, to make sure we're not going to introduce something like the famous nfsd inode cache bug again. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-14xfs: event tracing supportChristoph Hellwig
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>
2009-12-11xfs: remove incorrect sparse annotation for xfs_iget_cache_missChristoph Hellwig
xfs_iget_cache_miss does not get called with the pag_ici_lock held, so the __releases annotation is incorrect. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <david@fromorbit.com> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-11xfs: reset the i_iolock lock class in the reclaim pathChristoph Hellwig
The iolock is used for protecting reads, writes and block truncates against each other. We have two classes of callers, the first one is induced by a file operation and requires a reference to the inode be held and not dropped after the operation is done: - xfs_vm_vmap, xfs_vn_fallocate, xfs_read, xfs_write, xfs_splice_read, xfs_splice_write and xfs_setattr are all implementations of VFS methods that require a live inode - xfs_getbmap and xfs_swap_extents are ioctl subcommand for which the same is true - xfs_truncate_file is only called on quota inodes just returned from xfs_iget - xfs_sync_inode_data does the lock just after an igrab() - xfs_filestream_associate and xfs_filestream_new_ag take the iolock on the parent inode of an inode which by VFS rules must be referenced And we have various calls to truncate blocks past EOF or the whole file when dropping the last reference to an inode. Unfortunately lockdep complains when we do memory allocations that can recurse into the filesystem in the first class because the second class happens to take the same lock. To avoid this re-init the iolock in the beginning of xfs_fs_clear_inode to get a new lock class. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Alex Elder <aelder@sgi.com> Signed-off-by: Alex Elder <aelder@sgi.com>
2009-09-01xfs: simplify xfs_trans_igetChristoph Hellwig
xfs_trans_iget is a wrapper for xfs_iget that adds the inode to the transaction after it is read. Except when the inode already is in the inode cache, in which case it returns the existing locked inode with increment lock recursion counts. Now, no one in the tree every decrements these lock recursion counts, so any user of this gets a potential double unlock when both the original owner of the inode and the xfs_trans_iget caller unlock it. When looking back in a git bisect in the historic XFS tree there was only one place that decremented these counts, xfs_trans_iput. Introduced in commit ca25df7a840f426eb566d52667b6950b92bb84b5 by Adam Sweeney in 1993, and removed in commit 19f899a3ab155ff6a49c0c79b06f2f61059afaf3 by Steve Lord in 2003. And as long as it didn't slip through git bisects cracks never actually used in that time frame. A quick audit of the callers of xfs_trans_iget shows that no caller really relies on this behaviour fortunately - xfs_ialloc allows this inode from disk so it must not be there before, and all the RT allocator routines only every add each RT bitmap inode once. In addition to removing lots of code and reducing the size of the inode item this patch also avoids the double inode cache lookup in each create/mkdir/mknod transaction. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Alex Elder <aelder@sgi.com> Signed-off-by: Felix Blyakher <felixb@sgi.com>
2009-09-01xfs: merge fsync and O_SYNC handlingChristoph Hellwig
The guarantees for O_SYNC are exactly the same as the ones we need to make for an fsync call (and given that Linux O_SYNC is O_DSYNC the equivalent is fdadatasync, but we treat both the same in XFS), except with a range data writeout. Jan Kara has started unifying these two path for filesystems using the generic helpers, and I've started to look at XFS. The actual transaction commited by xfs_fsync and xfs_write_sync_logforce has a different transaction number, but actually is exactly the same. We'll only use the fsync transaction going forward. One major difference is that xfs_write_sync_logforce never issues a cache flush unless we commit a transaction causing that as a side-effect, which is an obvious bug in the O_SYNC handling. Second all the locking and i_update_size vs i_update_core changes from 978b7237123d007b9fa983af6e0e2fa8f97f9934 never made it to xfs_write_sync_logforce, so we add them back. To make xfs_fsync easily usable from the O_SYNC path, the filemap_fdatawait call is moved up to xfs_file_fsync, so that we don't wait on the whole file after we already waited for our portion in xfs_write. We'll also use a plain call to filemap_write_and_wait_range instead of the previous sync_page_rang which did it in two steps including an half-hearted inode write out that doesn't help us. Once we're done with this also remove the now useless i_update_size tracking. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Felix Blyakher <felixb@sgi.com> Signed-off-by: Felix Blyakher <felixb@sgi.com>
2009-08-17xfs: fix locking in xfs_iget_cache_hitChristoph Hellwig
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>
2009-08-07xfs: fix freeing of inodes not yet added to the inode cacheChristoph Hellwig
When freeing an inode that lost race getting added to the inode cache we must not call into ->destroy_inode, because that would delete the inode that won the race from the inode cache radix tree. This patch uses splits a new xfs_inode_free helper out of xfs_ireclaim and uses that plus __destroy_inode to make sure we really only free the memory allocted for the inode that lost the race, and not mess with the inode cache state. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Eric Sandeen <sandeen@sandeen.net> Reported-by: Alex Samad <alex@samad.com.au> Reported-by: Andrew Randrianasulu <randrik@mail.ru> Reported-by: Stephane <sharnois@max-t.com> Reported-by: Tommy <tommy@news-service.com> Reported-by: Miah Gregory <mace@darksilence.net> Reported-by: Gabriel Barazer <gabriel@oxeva.fr> Reported-by: Leandro Lucarella <llucax@gmail.com> Reported-by: Daniel Burr <dburr@fami.com.au> Reported-by: Nickolay <newmail@spaces.ru> Reported-by: Michael Guntsche <mike@it-loops.com> Reported-by: Dan Carley <dan.carley+linuxkern-bugs@gmail.com> Reported-by: Michael Ole Olsen <gnu@gmx.net> Reported-by: Michael Weissenbacher <mw@dermichi.com> Reported-by: Martin Spott <Martin.Spott@mgras.net> Reported-by: Christian Kujau <lists@nerdbynature.de> Tested-by: Michael Guntsche <mike@it-loops.com> Tested-by: Dan Carley <dan.carley+linuxkern-bugs@gmail.com> Tested-by: Christian Kujau <lists@nerdbynature.de>
2009-08-07vfs: fix inode_init_always calling conventionChristoph Hellwig
Currently inode_init_always calls into ->destroy_inode if the additional initialization fails. That's not only counter-intuitive because inode_init_always did not allocate the inode structure, but in case of XFS it's actively harmful as ->destroy_inode might delete the inode from a radix-tree that has never been added. This in turn might end up deleting the inode for the same inum that has been instanciated by another process and cause lots of cause subtile problems. Also in the case of re-initializing a reclaimable inode in XFS it would free an inode we still want to keep alive. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
2009-06-24switch xfs to generic acl caching helpersAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-10xfs: use generic Posix ACL codeChristoph Hellwig
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>
2009-06-08xfs: kill xfs_qmopsChristoph Hellwig
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>