17 Dec, 2011

1 commit

  • …inux/kernel/git/mason/linux-btrfs

    * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
    Btrfs: unplug every once and a while
    Btrfs: deal with NULL srv_rsv in the delalloc inode reservation code
    Btrfs: only set cache_generation if we setup the block group
    Btrfs: don't panic if orphan item already exists
    Btrfs: fix leaked space in truncate
    Btrfs: fix how we do delalloc reservations and how we free reservations on error
    Btrfs: deal with enospc from dirtying inodes properly
    Btrfs: fix num_workers_starting bug and other bugs in async thread
    BTRFS: Establish i_ops before calling d_instantiate
    Btrfs: add a cond_resched() into the worker loop
    Btrfs: fix ctime update of on-disk inode
    btrfs: keep orphans for subvolume deletion
    Btrfs: fix inaccurate available space on raid0 profile
    Btrfs: fix wrong disk space information of the files
    Btrfs: fix wrong i_size when truncating a file to a larger size
    Btrfs: fix btrfs_end_bio to deal with write errors to a single mirror

    * 'for-linus-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
    btrfs: lower the dirty balance poll interval

    Linus Torvalds
     

16 Dec, 2011

1 commit


12 Nov, 2011

1 commit

  • * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
    btrfs: rename the option to nospace_cache
    Btrfs: handle bio_add_page failure gracefully in scrub
    Btrfs: fix deadlock caused by the race between relocation
    Btrfs: only map pages if we know we need them when reading the space cache
    Btrfs: fix orphan backref nodes
    Btrfs: Abstract similar code for btrfs_block_rsv_add{, _noflush}
    Btrfs: fix unreleased path in btrfs_orphan_cleanup()
    Btrfs: fix no reserved space for writing out inode cache
    Btrfs: fix nocow when deleting the item
    Btrfs: tweak the delayed inode reservations again
    Btrfs: rework error handling in btrfs_mount()
    Btrfs: close devices on all error paths in open_ctree()
    Btrfs: avoid null dereference and leaks when bailing from open_ctree()
    Btrfs: fix subvol_name leak on error in btrfs_mount()
    Btrfs: fix memory leak in btrfs_parse_early_options()
    Btrfs: fix our reservations for updating an inode when completing io
    Btrfs: fix oops on NULL trans handle in btrfs_truncate
    btrfs: fix double-free 'tree_root' in 'btrfs_mount()'

    Linus Torvalds
     

11 Nov, 2011

1 commit

  • Josef sent along an incremental to the inode reservation
    code to make sure we try and fall back to directly updating
    the inode item if things go horribly wrong.

    This reworks that patch slightly, adding a fallback function
    that will always try to update the inode item directly without
    going through the delayed_inode code.

    Signed-off-by: Chris Mason

    Chris Mason
     

09 Nov, 2011

1 commit

  • People have been reporting ENOSPC crashes in finish_ordered_io. This is because
    we try to steal from the delalloc block rsv to satisfy a reservation to update
    the inode. The problem with this is we don't explicitly save space for updating
    the inode when doing delalloc. This is kind of a problem and we've gotten away
    with this because way back when we just stole from the delalloc reserve without
    any questions, and this worked out fine because generally speaking the leaf had
    been modified either by the mtime update when we did the original write or
    because we just updated the leaf when we inserted the file extent item, only on
    rare occasions had the leaf not actually been modified, and that was still ok
    because we'd just use a block or two out of the over-reservation that is
    delalloc.

    Then came the delayed inode stuff. This is amazing, except it wants a full
    reservation for updating the inode since it may do it at some point down the
    road after we've written the blocks and we have to recow everything again. This
    worked out because the delayed inode stuff just stole from the global reserve,
    that is until recently when I changed that because it caused other problems.

    So here we are, we're doing everything right and being screwed for it. So take
    an extra reservation for the inode at delalloc reservation time and carry it
    through the life of the delalloc reservation. If we need it we can steal it in
    the delayed inode stuff. If we have already stolen it try and do a normal
    metadata reservation. If that fails try to steal from the delalloc reservation.
    If _that_ fails we'll get a WARN_ON() so I can start thinking of a better way to
    solve this and in the meantime we'll steal from the global reserve.

    With this patch I ran xfstests 13 in a loop for a couple of hours and didn't see
    any problems.

    Signed-off-by: Josef Bacik
    Signed-off-by: Chris Mason

    Josef Bacik
     

07 Nov, 2011

1 commit

  • * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (114 commits)
    Btrfs: check for a null fs root when writing to the backup root log
    Btrfs: fix race during transaction joins
    Btrfs: fix a potential btrfs_bio leak on scrub fixups
    Btrfs: rename btrfs_bio multi -> bbio for consistency
    Btrfs: stop leaking btrfs_bios on readahead
    Btrfs: stop the readahead threads on failed mount
    Btrfs: fix extent_buffer leak in the metadata IO error handling
    Btrfs: fix the new inspection ioctls for 32 bit compat
    Btrfs: fix delayed insertion reservation
    Btrfs: ClearPageError during writepage and clean_tree_block
    Btrfs: be smarter about committing the transaction in reserve_metadata_bytes
    Btrfs: make a delayed_block_rsv for the delayed item insertion
    Btrfs: add a log of past tree roots
    btrfs: separate superblock items out of fs_info
    Btrfs: use the global reserve when truncating the free space cache inode
    Btrfs: release metadata from global reserve if we have to fallback for unlink
    Btrfs: make sure to flush queued bios if write_cache_pages waits
    Btrfs: fix extent pinning bugs in the tree log
    Btrfs: make sure btrfs_remove_free_space doesn't leak EAGAIN
    Btrfs: don't wait as long for more batches during SSD log commit
    ...

    Linus Torvalds
     

06 Nov, 2011

2 commits

  • We all keep getting those stupid warnings from use_block_rsv when running
    stress.sh, and it's because the delayed insertion stuff is being stupid. It's
    not the delayed insertion stuffs fault, it's all just stupid. When marking an
    inode dirty for oh say updating the time on it, we just do a
    btrfs_join_transaction, which doesn't reserve any space. This is stupid because
    we're going to have to have space reserve to make this change, but we do it
    because it's fast because chances are we're going to call it over and over again
    and it doesn't matter. Well thanks to the delayed insertion stuff this is
    mostly the case, so we do actually need to make this reservation. So if
    trans->bytes_reserved is 0 then try to do a normal reservation. If not return
    ENOSPC which will make the btrfs_dirty_inode start a proper transaction which
    will let it do the whole ENOSPC dance and reserve enough space for the delayed
    insertion to steal the reservation from the transaction.

    The other stupid thing we do is not reserve space for the inode when writing to
    the thing. Usually this is ok since we have to update the time so we'd have
    already done all this work before we get to the endio stuff, so it doesn't
    matter. But this is stupid because we could write the data after the
    transaction commits where we changed the mtime of the inode so we have to cow
    all the way down to the inode anyway. This used to be masked by the delalloc
    reservation stuff, but because we delay the update it doesn't get masked in this
    case. So again the delayed insertion stuff bites us in the ass. So if our
    trans->block_rsv is delalloc, just steal the reservation from the delalloc
    reserve. Hopefully this won't bite us in the ass, but I've said that before.

    With this patch stress.sh no longer spits out those stupid warnings (famous last
    words). Thanks,

    Signed-off-by: Josef Bacik
    Signed-off-by: Chris Mason

    Josef Bacik
     
  • I've been hitting warnings in use_block_rsv when running the delayed insertion
    stuff. It's because we will readjust global block rsv based on what is in use,
    which means we could end up discarding reservations that are for the delayed
    insertion stuff. So instead create a seperate block rsv for the delayed
    insertion stuff. This will also make it easier to debug problems with the
    delayed insertion reservations since we will know that only the delayed
    insertion code touches this block_rsv. Thanks,

    Signed-off-by: Josef Bacik
    Signed-off-by: Chris Mason

    Josef Bacik
     

02 Nov, 2011

1 commit


28 Jul, 2011

1 commit

  • The btrfs metadata btree is the source of significant
    lock contention, especially in the root node. This
    commit changes our locking to use a reader/writer
    lock.

    The lock is built on top of rw spinlocks, and it
    extends the lock tracking to remember if we have a
    read lock or a write lock when we go to blocking. Atomics
    count the number of blocking readers or writers at any
    given time.

    It removes all of the adaptive spinning from the old code
    and uses only the spinning/blocking hints inside of btrfs
    to decide when it should continue spinning.

    In read heavy workloads this is dramatically faster. In write
    heavy workloads we're still faster because of less contention
    on the root node lock.

    We suffer slightly in dbench because we schedule more often
    during write locks, but all other benchmarks so far are improved.

    Signed-off-by: Chris Mason

    Chris Mason
     

27 Jun, 2011

1 commit

  • When iputting the inode, We may leave the delayed nodes if they have some
    delayed items that have not been dealt with. So when the inode is read again,
    we must look up the relative delayed node, and use the information in it to
    initialize the inode. Or we will get inconsonant inode information, it may
    cause that the same directory index number is allocated again, and hit the
    following oops:

    [ 5447.554187] err add delayed dir index item(name: pglog_0.965_0) into the
    insertion tree of the delayed node(root id: 262, inode id: 258, errno: -17)
    [ 5447.569766] ------------[ cut here ]------------
    [ 5447.575361] kernel BUG at fs/btrfs/delayed-inode.c:1301!
    [SNIP]
    [ 5447.790721] Call Trace:
    [ 5447.793191] [] btrfs_insert_dir_item+0x189/0x1bb [btrfs]
    [ 5447.800156] [] btrfs_add_link+0x12b/0x191 [btrfs]
    [ 5447.806517] [] btrfs_add_nondir+0x31/0x58 [btrfs]
    [ 5447.812876] [] btrfs_create+0xf9/0x197 [btrfs]
    [ 5447.818961] [] vfs_create+0x72/0x92
    [ 5447.824090] [] do_last+0x22c/0x40b
    [ 5447.829133] [] path_openat+0xc0/0x2ef
    [ 5447.834438] [] ? __perf_event_task_sched_out+0x24/0x44
    [ 5447.841216] [] ? perf_event_task_sched_out+0x59/0x67
    [ 5447.847846] [] do_filp_open+0x3d/0x87
    [ 5447.853156] [] ? strncpy_from_user+0x43/0x4d
    [ 5447.859072] [] ? getname_flags+0x2e/0x80
    [ 5447.864636] [] ? do_getname+0x14b/0x173
    [ 5447.870112] [] ? audit_getname+0x16/0x26
    [ 5447.875682] [] ? spin_lock+0xe/0x10
    [ 5447.880882] [] do_sys_open+0x69/0xae
    [ 5447.886153] [] sys_open+0x20/0x22
    [ 5447.891114] [] system_call_fastpath+0x16/0x1b

    Fix it by reusing the old delayed node.

    Reported-by: Jim Schutt
    Signed-off-by: Miao Xie
    Tested-by: Jim Schutt
    Signed-off-by: Chris Mason

    Miao Xie
     

18 Jun, 2011

2 commits

  • Snapshot creation has two phases. One is the initial snapshot setup,
    and the second is done during commit, while nobody is allowed to modify
    the root we are snapshotting.

    The delayed metadata insertion code can break that rule, it does a
    delayed inode update on the inode of the parent of the snapshot,
    and delayed directory item insertion.

    This makes sure to run the pending delayed operations before we
    record the snapshot root, which avoids corruptions.

    Signed-off-by: Chris Mason

    Chris Mason
     
  • We have migrated the space for the delayed inode items from
    trans_block_rsv to global_block_rsv, but we forgot to set trans->block_rsv to
    global_block_rsv when we doing delayed inode operations, and the following Oops
    happened:

    [ 9792.654889] ------------[ cut here ]------------
    [ 9792.654898] WARNING: at fs/btrfs/extent-tree.c:5681
    btrfs_alloc_free_block+0xca/0x27c [btrfs]()
    [ 9792.654899] Hardware name: To Be Filled By O.E.M.
    [ 9792.654900] Modules linked in: btrfs zlib_deflate libcrc32c
    ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 ip6table_filter ip6_tables
    arc4 rt61pci rt2x00pci rt2x00lib snd_hda_codec_hdmi mac80211
    snd_hda_codec_realtek cfg80211 snd_hda_intel edac_core snd_seq rfkill
    pcspkr serio_raw snd_hda_codec eeprom_93cx6 edac_mce_amd sp5100_tco
    i2c_piix4 k10temp snd_hwdep snd_seq_device snd_pcm floppy r8169 xhci_hcd
    mii snd_timer snd soundcore snd_page_alloc ipv6 firewire_ohci pata_acpi
    ata_generic firewire_core pata_via crc_itu_t radeon ttm drm_kms_helper
    drm i2c_algo_bit i2c_core [last unloaded: scsi_wait_scan]
    [ 9792.654919] Pid: 2762, comm: rm Tainted: G W 2.6.39+ #1
    [ 9792.654920] Call Trace:
    [ 9792.654922] [] warn_slowpath_common+0x83/0x9b
    [ 9792.654925] [] warn_slowpath_null+0x1a/0x1c
    [ 9792.654933] [] btrfs_alloc_free_block+0xca/0x27c [btrfs]
    [ 9792.654945] [] ? map_extent_buffer+0x6e/0xa8 [btrfs]
    [ 9792.654953] [] __btrfs_cow_block+0xfc/0x30c [btrfs]
    [ 9792.654963] [] ? btrfs_buffer_uptodate+0x47/0x58 [btrfs]
    [ 9792.654970] [] ? read_block_for_search+0x94/0x368 [btrfs]
    [ 9792.654978] [] btrfs_cow_block+0xfe/0x146 [btrfs]
    [ 9792.654986] [] btrfs_search_slot+0x14d/0x4b6 [btrfs]
    [ 9792.654997] [] ? map_extent_buffer+0x6e/0xa8 [btrfs]
    [ 9792.655022] [] btrfs_lookup_inode+0x2f/0x8f [btrfs]
    [ 9792.655025] [] ? _cond_resched+0xe/0x22
    [ 9792.655027] [] ? mutex_lock+0x29/0x50
    [ 9792.655039] [] btrfs_update_delayed_inode+0x72/0x137 [btrfs]
    [ 9792.655051] [] btrfs_run_delayed_items+0x90/0xdb [btrfs]
    [ 9792.655062] [] btrfs_commit_transaction+0x228/0x654 [btrfs]
    [ 9792.655064] [] ? remove_wait_queue+0x3a/0x3a
    [ 9792.655075] [] btrfs_evict_inode+0x14d/0x202 [btrfs]
    [ 9792.655077] [] evict+0x71/0x111
    [ 9792.655079] [] iput+0x12a/0x132
    [ 9792.655081] [] do_unlinkat+0x106/0x155
    [ 9792.655083] [] ? path_put+0x1f/0x23
    [ 9792.655085] [] ? audit_syscall_entry+0x145/0x171
    [ 9792.655087] [] ? putname+0x34/0x36
    [ 9792.655090] [] sys_unlinkat+0x29/0x2b
    [ 9792.655092] [] system_call_fastpath+0x16/0x1b
    [ 9792.655093] ---[ end trace 02b696eb02b3f768 ]---

    This patch fix it by setting the reservation of the transaction handle to the
    correct one.

    Reported-by: Josef Bacik
    Signed-off-by: Miao Xie
    Signed-off-by: Chris Mason

    Miao Xie
     

04 Jun, 2011

2 commits

  • With Linus' tree, today's linux-next build (powercp ppc64_defconfig)
    produced this warning:

    fs/btrfs/delayed-inode.c: In function 'btrfs_delayed_update_inode':
    fs/btrfs/delayed-inode.c:1598:6: warning: 'ret' may be used
    uninitialized in this function

    Introduced by commit 16cdcec736cd ("btrfs: implement delayed inode items
    operation").

    This fixes a bug in btrfs_update_inode(): if the returned value from
    btrfs_delayed_update_inode is a nonzero garbage, inode stat data are not
    updated and several call paths may hit a BUG_ON or fail with strange
    code.

    Reported-by: Stephen Rothwell
    Signed-off-by: David Sterba

    David Sterba
     
  • The nitems counter needs to start at zero

    Signed-off-by: Chris Mason

    Chris Mason
     

28 May, 2011

1 commit

  • git://git.kernel.org/pub/scm/linux/kernel/git/josef/btrfs-work into for-linus

    Conflicts:
    fs/btrfs/disk-io.c
    fs/btrfs/extent-tree.c
    fs/btrfs/free-space-cache.c
    fs/btrfs/inode.c
    fs/btrfs/transaction.c

    Signed-off-by: Chris Mason

    Chris Mason
     

23 May, 2011

1 commit


22 May, 2011

1 commit


21 May, 2011

1 commit

  • Changelog V5 -> V6:
    - Fix oom when the memory load is high, by storing the delayed nodes into the
    root's radix tree, and letting btrfs inodes go.

    Changelog V4 -> V5:
    - Fix the race on adding the delayed node to the inode, which is spotted by
    Chris Mason.
    - Merge Chris Mason's incremental patch into this patch.
    - Fix deadlock between readdir() and memory fault, which is reported by
    Itaru Kitayama.

    Changelog V3 -> V4:
    - Fix nested lock, which is reported by Itaru Kitayama, by updating space cache
    inode in time.

    Changelog V2 -> V3:
    - Fix the race between the delayed worker and the task which does delayed items
    balance, which is reported by Tsutomu Itoh.
    - Modify the patch address David Sterba's comment.
    - Fix the bug of the cpu recursion spinlock, reported by Chris Mason

    Changelog V1 -> V2:
    - break up the global rb-tree, use a list to manage the delayed nodes,
    which is created for every directory and file, and used to manage the
    delayed directory name index items and the delayed inode item.
    - introduce a worker to deal with the delayed nodes.

    Compare with Ext3/4, the performance of file creation and deletion on btrfs
    is very poor. the reason is that btrfs must do a lot of b+ tree insertions,
    such as inode item, directory name item, directory name index and so on.

    If we can do some delayed b+ tree insertion or deletion, we can improve the
    performance, so we made this patch which implemented delayed directory name
    index insertion/deletion and delayed inode update.

    Implementation:
    - introduce a delayed root object into the filesystem, that use two lists to
    manage the delayed nodes which are created for every file/directory.
    One is used to manage all the delayed nodes that have delayed items. And the
    other is used to manage the delayed nodes which is waiting to be dealt with
    by the work thread.
    - Every delayed node has two rb-tree, one is used to manage the directory name
    index which is going to be inserted into b+ tree, and the other is used to
    manage the directory name index which is going to be deleted from b+ tree.
    - introduce a worker to deal with the delayed operation. This worker is used
    to deal with the works of the delayed directory name index items insertion
    and deletion and the delayed inode update.
    When the delayed items is beyond the lower limit, we create works for some
    delayed nodes and insert them into the work queue of the worker, and then
    go back.
    When the delayed items is beyond the upper bound, we create works for all
    the delayed nodes that haven't been dealt with, and insert them into the work
    queue of the worker, and then wait for that the untreated items is below some
    threshold value.
    - When we want to insert a directory name index into b+ tree, we just add the
    information into the delayed inserting rb-tree.
    And then we check the number of the delayed items and do delayed items
    balance. (The balance policy is above.)
    - When we want to delete a directory name index from the b+ tree, we search it
    in the inserting rb-tree at first. If we look it up, just drop it. If not,
    add the key of it into the delayed deleting rb-tree.
    Similar to the delayed inserting rb-tree, we also check the number of the
    delayed items and do delayed items balance.
    (The same to inserting manipulation)
    - When we want to update the metadata of some inode, we cached the data of the
    inode into the delayed node. the worker will flush it into the b+ tree after
    dealing with the delayed insertion and deletion.
    - We will move the delayed node to the tail of the list after we access the
    delayed node, By this way, we can cache more delayed items and merge more
    inode updates.
    - If we want to commit transaction, we will deal with all the delayed node.
    - the delayed node will be freed when we free the btrfs inode.
    - Before we log the inode items, we commit all the directory name index items
    and the delayed inode update.

    I did a quick test by the benchmark tool[1] and found we can improve the
    performance of file creation by ~15%, and file deletion by ~20%.

    Before applying this patch:
    Create files:
    Total files: 50000
    Total time: 1.096108
    Average time: 0.000022
    Delete files:
    Total files: 50000
    Total time: 1.510403
    Average time: 0.000030

    After applying this patch:
    Create files:
    Total files: 50000
    Total time: 0.932899
    Average time: 0.000019
    Delete files:
    Total files: 50000
    Total time: 1.215732
    Average time: 0.000024

    [1] http://marc.info/?l=linux-btrfs&m=128212635122920&q=p3

    Many thanks for Kitayama-san's help!

    Signed-off-by: Miao Xie
    Reviewed-by: David Sterba
    Tested-by: Tsutomu Itoh
    Tested-by: Itaru Kitayama
    Signed-off-by: Chris Mason

    Miao Xie