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2010-10-26Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (52 commits) split invalidate_inodes() fs: skip I_FREEING inodes in writeback_sb_inodes fs: fold invalidate_list into invalidate_inodes fs: do not drop inode_lock in dispose_list fs: inode split IO and LRU lists fs: switch bdev inode bdi's correctly fs: fix buffer invalidation in invalidate_list fsnotify: use dget_parent smbfs: use dget_parent exportfs: use dget_parent fs: use RCU read side protection in d_validate fs: clean up dentry lru modification fs: split __shrink_dcache_sb fs: improve DCACHE_REFERENCED usage fs: use percpu counter for nr_dentry and nr_dentry_unused fs: simplify __d_free fs: take dcache_lock inside __d_path fs: do not assign default i_ino in new_inode fs: introduce a per-cpu last_ino allocator new helper: ihold() ...
2010-10-26IMA: move read counter into struct inodeEric Paris
IMA currently allocated an inode integrity structure for every inode in core. This stucture is about 120 bytes long. Most files however (especially on a system which doesn't make use of IMA) will never need any of this space. The problem is that if IMA is enabled we need to know information about the number of readers and the number of writers for every inode on the box. At the moment we collect that information in the per inode iint structure and waste the rest of the space. This patch moves those counters into the struct inode so we can eventually stop allocating an IMA integrity structure except when absolutely needed. This patch does the minimum needed to move the location of the data. Further cleanups, especially the location of counter updates, may still be possible. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-25split invalidate_inodes()Al Viro
Pull removal of fsnotify marks into generic_shutdown_super(). Split umount-time work into a new function - evict_inodes(). Make sure that invalidate_inodes() will be able to cope with I_FREEING once we change locking in iput(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25fs: fold invalidate_list into invalidate_inodesChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25fs: do not drop inode_lock in dispose_listChristoph Hellwig
Despite the comment above it we can not safely drop the lock here. invalidate_list is called from many other places that just umount. Also switch to proper list macros now that we never drop the lock. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25fs: inode split IO and LRU listsNick Piggin
The use of the same inode list structure (inode->i_list) for two different list constructs with different lifecycles and purposes makes it impossible to separate the locking of the different operations. Therefore, to enable the separation of the locking of the writeback and reclaim lists, split the inode->i_list into two separate lists dedicated to their specific tracking functions. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25fs: fix buffer invalidation in invalidate_listChristoph Hellwig
We must not call invalidate_inode_buffers in invalidate_list unless the inode can be reclaimed. If we remove the buffer association of a busy inode fsync won't find the buffers anymore. As invalidate_inode_buffers is called from various others sources than umount this actually does matter in practice. While at it change the loop to a more natural form and remove the WARN_ON for I_NEW, wich we already tested a few lines above. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25fs: do not assign default i_ino in new_inodeChristoph Hellwig
Instead of always assigning an increasing inode number in new_inode move the call to assign it into those callers that actually need it. For now callers that need it is estimated conservatively, that is the call is added to all filesystems that do not assign an i_ino by themselves. For a few more filesystems we can avoid assigning any inode number given that they aren't user visible, and for others it could be done lazily when an inode number is actually needed, but that's left for later patches. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25fs: introduce a per-cpu last_ino allocatorEric Dumazet
new_inode() dirties a contended cache line to get increasing inode numbers. This limits performance on workloads that cause significant parallel inode allocation. Solve this problem by using a per_cpu variable fed by the shared last_ino in batches of 1024 allocations. This reduces contention on the shared last_ino, and give same spreading ino numbers than before (i.e. same wraparound after 2^32 allocations). Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25new helper: ihold()Al Viro
Clones an existing reference to inode; caller must already hold one. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25fs: remove inode_add_to_list/__inode_add_to_listChristoph Hellwig
Split up inode_add_to_list/__inode_add_to_list. Locking for the two lists will be split soon so these helpers really don't buy us much anymore. The __ prefixes for the sb list helpers will go away soon, but until inode_lock is gone we'll need them to distinguish between the locked and unlocked variants. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25fs: move i_count increments into find_inode/find_inode_fastChristoph Hellwig
Now that iunique is not abusing find_inode anymore we can move the i_ref increment back to where it belongs. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25fs: Stop abusing find_inode_fast in iuniqueChristoph Hellwig
Stop abusing find_inode_fast for iunique and opencode the inode hash walk. Introduce a new iunique_lock to protect the iunique counters once inode_lock is removed. Based on a patch originally from Nick Piggin. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25fs: Factor inode hash operations into functionsDave Chinner
Before replacing the inode hash locking with a more scalable mechanism, factor the removal of the inode from the hashes rather than open coding it in several places. Based on a patch originally from Nick Piggin. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25fs: Implement lazy LRU updates for inodesNick Piggin
Convert the inode LRU to use lazy updates to reduce lock and cacheline traffic. We avoid moving inodes around in the LRU list during iget/iput operations so these frequent operations don't need to access the LRUs. Instead, we defer the refcount checks to reclaim-time and use a per-inode state flag, I_REFERENCED, to tell reclaim that iget has touched the inode in the past. This means that only reclaim should be touching the LRU with any frequency, hence significantly reducing lock acquisitions and the amount contention on LRU updates. This also removes the inode_in_use list, which means we now only have one list for tracking the inode LRU status. This makes it much simpler to split out the LRU list operations under it's own lock. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25fs: Convert nr_inodes and nr_unused to per-cpu countersDave Chinner
The number of inodes allocated does not need to be tied to the addition or removal of an inode to/from a list. If we are not tied to a list lock, we could update the counters when inodes are initialised or destroyed, but to do that we need to convert the counters to be per-cpu (i.e. independent of a lock). This means that we have the freedom to change the list/locking implementation without needing to care about the counters. Based on a patch originally from Eric Dumazet. [AV: cleaned up a bit, fixed build breakage on weird configs Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25new helper: inode_unhashed()Al Viro
note: for race-free uses you inode_lock held Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25unexport invalidate_inodesAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25lockdep: fixup checking of dir inode annotationNamhyung Kim
Since inode->i_mode shares its bits for S_IFMT, S_ISDIR should be used to distinguish whether it is a dir or not. Signed-off-by: Namhyung Kim <namhyung@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25fs: mark destroy_inode staticChristoph Hellwig
Hugetlbfs used to need it, but after the destroy_inode and evict_inode changes it's not required anymore. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-10Merge branch 'for-linus' of git://git.infradead.org/users/eparis/notifyLinus Torvalds
* 'for-linus' of git://git.infradead.org/users/eparis/notify: (132 commits) fanotify: use both marks when possible fsnotify: pass both the vfsmount mark and inode mark fsnotify: walk the inode and vfsmount lists simultaneously fsnotify: rework ignored mark flushing fsnotify: remove global fsnotify groups lists fsnotify: remove group->mask fsnotify: remove the global masks fsnotify: cleanup should_send_event fanotify: use the mark in handler functions audit: use the mark in handler functions dnotify: use the mark in handler functions inotify: use the mark in handler functions fsnotify: send fsnotify_mark to groups in event handling functions fsnotify: Exchange list heads instead of moving elements fsnotify: srcu to protect read side of inode and vfsmount locks fsnotify: use an explicit flag to indicate fsnotify_destroy_mark has been called fsnotify: use _rcu functions for mark list traversal fsnotify: place marks on object in order of group memory address vfs/fsnotify: fsnotify_close can delay the final work in fput fsnotify: store struct file not struct path ... Fix up trivial delete/modify conflict in fs/notify/inotify/inotify.c.
2010-08-09All filesystems that need invalidate_inode_buffers() are doing that explicitlyAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09convert remaining ->clear_inode() to ->evict_inode()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09Make ->drop_inode() just return whether inode needs to be droppedAl Viro
... and let iput_final() do the actual eviction or retention Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09fs/inode.c:clear_inode() is goneAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09fs/inode.c:evict() doesn't care about delete vs. non-delete paths nowAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09->delete_inode() is goneAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09new helper: end_writeback()Al Viro
Essentially, the minimal variant of ->evict_inode(). It's a trimmed-down clear_inode(), sans any fs callbacks. Once it returns we know that no async writeback will be happening; every ->evict_inode() instance should do that once and do that before doing anything ->write_inode() could interfere with (e.g. freeing the on-disk inode). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09Take ->i_bdev/->i_cdev handling out of clear_inode()Al Viro
All call chains to clear_inode() pass through evict_inode() and clear_inode() should be called by evict_inode() exactly once. So we can pull i_bdev/i_cdev detaching up to evict_inode() itself. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09generic_detach_inode() can be static nowAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09New method - evict_inode()Al Viro
Hybrid of ->clear_inode() and ->delete_inode(); if present, does all fs work to be done when in-core inode is about to be gone, for whatever reason. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09unify fs/inode.c callers of clear_inode()Al Viro
For now, just a straightforward merge Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09simplify checks for I_CLEAR/I_FREEINGAl Viro
add I_CLEAR instead of replacing I_FREEING with it. I_CLEAR is equivalent to I_FREEING for almost all code looking at either; it's there to keep track of having called clear_inode() exactly once per inode lifetime, at some point after having set I_FREEING. I_CLEAR and I_FREEING never get set at the same time with the current code, so we can switch to setting i_flags to I_FREEING | I_CLEAR instead of I_CLEAR without loss of information. As the result of such change, checks become simpler and the amount of code that needs to know about I_CLEAR shrinks a lot. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-07-28fsnotify: rename fsnotify_mark_entry to just fsnotify_markEric Paris
The name is long and it serves no real purpose. So rename fsnotify_mark_entry to just fsnotify_mark. Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28inotify: remove inotify in kernel interfaceEric Paris
nothing uses inotify in the kernel, drop it! Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-19mm: add context argument to shrinker callbackDave Chinner
The current shrinker implementation requires the registered callback to have global state to work from. This makes it difficult to shrink caches that are not global (e.g. per-filesystem caches). Pass the shrinker structure to the callback so that users can embed the shrinker structure in the context the shrinker needs to operate on and get back to it in the callback via container_of(). Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-05-21vfs: Add inode uid,gid,mode init helperDmitry Monakhov
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-05-21fs: inode.c use atomic_inc_return in __igetRichard Kennedy
Using atomic_inc_return in __iget(struct inode *inode) makes the intent of this code clearer and generates less code on processors that have this operation. On x86_64 this patch reduces the text size of inode.o by 12 bytes. Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk> ---- patch against 2.6.34-rc7 compiled & tested on x86_64 AMD X2 I've been running with this patch applied for several weeks with no obvious problems. regards Richard Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-04-12security: remove dead hook inode_deleteEric Paris
Unused hook. Remove. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2010-03-05dquot: move dquot initialization responsibility into the filesystemChristoph Hellwig
Currently various places in the VFS call vfs_dq_init directly. This means we tie the quota code into the VFS. Get rid of that and make the filesystem responsible for the initialization. For most metadata operations this is a straight forward move into the methods, but for truncate and open it's a bit more complicated. For truncate we currently only call vfs_dq_init for the sys_truncate case because open already takes care of it for ftruncate and open(O_TRUNC) - the new code causes an additional vfs_dq_init for those which is harmless. For open the initialization is moved from do_filp_open into the open method, which means it happens slightly earlier now, and only for regular files. The latter is fine because we don't need to initialize it for operations on special files, and we already do it as part of the namespace operations for directories. Add a dquot_file_open helper that filesystems that support generic quotas can use to fill in ->open. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz>
2010-03-05dquot: move dquot drop responsibility into the filesystemChristoph Hellwig
Currently clear_inode calls vfs_dq_drop directly. This means we tie the quota code into the VFS. Get rid of that and make the filesystem responsible for the drop inside the ->clear_inode superblock operation. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz>
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>
2009-10-25LSM: imbed ima calls in the security hooksMimi Zohar
Based on discussions on LKML and LSM, where there are consecutive security_ and ima_ calls in the vfs layer, move the ima_ calls to the existing security_ hooks. Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
2009-09-24vfs: optimize touch_time() tooAndi Kleen
Do a similar optimization as earlier for touch_atime. Getting the lock in mnt_get_write is relatively costly, so try all avenues to avoid it first. This patch is careful to still only update inode fields inside the lock region. This didn't show up in benchmarks, but it's easy enough to do. [akpm@linux-foundation.org: fix typo in comment] [hugh.dickins@tiscali.co.uk: fix inverted test of mnt_want_write_file()] Signed-off-by: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Valerie Aurora <vaurora@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Dave Hansen <haveblue@us.ibm.com> Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-09-24vfs: optimization for touch_atime()Andi Kleen
Some benchmark testing shows touch_atime to be high up in profile logs for IO intensive workloads. Most likely that's due to the lock in mnt_want_write(). Unfortunately touch_atime first takes the lock, and then does all the other tests that could avoid atime updates (like noatime or relatime). Do it the other way round -- first try to avoid the update and only then if that didn't succeed take the lock. That works because none of the atime avoidance tests rely on locking. This also eliminates a goto. Signed-off-by: Andi Kleen <ak@linux.intel.com> Cc: Christoph Hellwig <hch@infradead.org> Reviewed-by: Valerie Aurora <vaurora@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Dave Hansen <haveblue@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-09-24vfs: split generic_forget_inode() so that hugetlbfs does not have to copy itJan Kara
Hugetlbfs needs to do special things instead of truncate_inode_pages(). Currently, it copied generic_forget_inode() except for truncate_inode_pages() call which is asking for trouble (the code there isn't trivial). So create a separate function generic_detach_inode() which does all the list magic done in generic_forget_inode() and call it from hugetlbfs_forget_inode(). Signed-off-by: Jan Kara <jack@suse.cz> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-09-24fs/inode.c: add dev-id and inode number for debugging in init_special_inode()Manish Katiyar
Add device-id and inode number for better debugging. This was suggested by Andreas in one of the threads http://article.gmane.org/gmane.comp.file-systems.ext4/12062 . "If anyone has a chance, fixing this error message to be not-useless would be good... Including the device name and the inode number would help track down the source of the problem." Signed-off-by: Manish Katiyar <mkatiyar@gmail.com> Cc: Andreas Dilger <adilger@sun.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-09-23fs: turn iprune_mutex into rwsemNick Piggin
We have had a report of bad memory allocation latency during DVD-RAM (UDF) writing. This is causing the user's desktop session to become unusable. Jan tracked the cause of this down to UDF inode reclaim blocking: gnome-screens D ffff810006d1d598 0 20686 1 ffff810006d1d508 0000000000000082 ffff810037db6718 0000000000000800 ffff810006d1d488 ffffffff807e4280 ffffffff807e4280 ffff810006d1a580 ffff8100bccbc140 ffff810006d1a8c0 0000000006d1d4e8 ffff810006d1a8c0 Call Trace: [<ffffffff804477f3>] io_schedule+0x63/0xa5 [<ffffffff802c2587>] sync_buffer+0x3b/0x3f [<ffffffff80447d2a>] __wait_on_bit+0x47/0x79 [<ffffffff80447dc6>] out_of_line_wait_on_bit+0x6a/0x77 [<ffffffff802c24f6>] __wait_on_buffer+0x1f/0x21 [<ffffffff802c442a>] __bread+0x70/0x86 [<ffffffff88de9ec7>] :udf:udf_tread+0x38/0x3a [<ffffffff88de0fcf>] :udf:udf_update_inode+0x4d/0x68c [<ffffffff88de26e1>] :udf:udf_write_inode+0x1d/0x2b [<ffffffff802bcf85>] __writeback_single_inode+0x1c0/0x394 [<ffffffff802bd205>] write_inode_now+0x7d/0xc4 [<ffffffff88de2e76>] :udf:udf_clear_inode+0x3d/0x53 [<ffffffff802b39ae>] clear_inode+0xc2/0x11b [<ffffffff802b3ab1>] dispose_list+0x5b/0x102 [<ffffffff802b3d35>] shrink_icache_memory+0x1dd/0x213 [<ffffffff8027ede3>] shrink_slab+0xe3/0x158 [<ffffffff8027fbab>] try_to_free_pages+0x177/0x232 [<ffffffff8027a578>] __alloc_pages+0x1fa/0x392 [<ffffffff802951fa>] alloc_page_vma+0x176/0x189 [<ffffffff802822d8>] __do_fault+0x10c/0x417 [<ffffffff80284232>] handle_mm_fault+0x466/0x940 [<ffffffff8044b922>] do_page_fault+0x676/0xabf This blocks with iprune_mutex held, which then blocks other reclaimers: X D ffff81009d47c400 0 17285 14831 ffff8100844f3728 0000000000000086 0000000000000000 ffff81000000e288 ffff81000000da00 ffffffff807e4280 ffffffff807e4280 ffff81009d47c400 ffffffff805ff890 ffff81009d47c740 00000000844f3808 ffff81009d47c740 Call Trace: [<ffffffff80447f8c>] __mutex_lock_slowpath+0x72/0xa9 [<ffffffff80447e1a>] mutex_lock+0x1e/0x22 [<ffffffff802b3ba1>] shrink_icache_memory+0x49/0x213 [<ffffffff8027ede3>] shrink_slab+0xe3/0x158 [<ffffffff8027fbab>] try_to_free_pages+0x177/0x232 [<ffffffff8027a578>] __alloc_pages+0x1fa/0x392 [<ffffffff8029507f>] alloc_pages_current+0xd1/0xd6 [<ffffffff80279ac0>] __get_free_pages+0xe/0x4d [<ffffffff802ae1b7>] __pollwait+0x5e/0xdf [<ffffffff8860f2b4>] :nvidia:nv_kern_poll+0x2e/0x73 [<ffffffff802ad949>] do_select+0x308/0x506 [<ffffffff802adced>] core_sys_select+0x1a6/0x254 [<ffffffff802ae0b7>] sys_select+0xb5/0x157 Now I think the main problem is having the filesystem block (and do IO) in inode reclaim. The problem is that this doesn't get accounted well and penalizes a random allocator with a big latency spike caused by work generated from elsewhere. I think the best idea would be to avoid this. By design if possible, or by deferring the hard work to an asynchronous context. If the latter, then the fs would probably want to throttle creation of new work with queue size of the deferred work, but let's not get into those details. Anyway, the other obvious thing we looked at is the iprune_mutex which is causing the cascading blocking. We could turn this into an rwsem to improve concurrency. It is unreasonable to totally ban all potentially slow or blocking operations in inode reclaim, so I think this is a cheap way to get a small improvement. This doesn't solve the whole problem of course. The process doing inode reclaim will still take the latency hit, and concurrent processes may end up contending on filesystem locks. So fs developers should keep these problems in mind. Signed-off-by: Nick Piggin <npiggin@suse.de> Cc: Jan Kara <jack@ucw.cz> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22const: mark remaining inode_operations as constAlexey Dobriyan
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22fs: make sure data stored into inode is properly seen before unlocking new inodeJan Kara
In theory it could happen that on one CPU we initialize a new inode but clearing of I_NEW | I_LOCK gets reordered before some of the initialization. Thus on another CPU we return not fully uptodate inode from iget_locked(). This seems to fix a corruption issue on ext3 mounted over NFS. [akpm@linux-foundation.org: add some commentary] Signed-off-by: Jan Kara <jack@suse.cz> Cc: Christoph Hellwig <hch@infradead.org> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>