btrfs: tests, use BTRFS_FS_STATE_DUMMY_FS_INFO instead of dummy root

2016-07-26T11:54:19+00:00

Now that we have a dummy fs_info associated with each test that uses a root, we don't need the DUMMY_ROOT bit anymore. This lets us make choices without needing an actual root like in e.g. btrfs_find_create_tree_block. Signed-off-by: Jeff Mahoney Signed-off-by: David Sterba

btrfs: Fix slab accounting flags

2016-07-26T11:52:25+00:00

BTRFS is using a variety of slab caches to satisfy internal needs. Those slab caches are always allocated with the SLAB_RECLAIM_ACCOUNT, meaning allocations from the caches are going to be accounted as SReclaimable. At the same time btrfs is not registering any shrinkers whatsoever, thus preventing memory from the slabs to be shrunk. This means those caches are not in fact reclaimable. To fix this remove the SLAB_RECLAIM_ACCOUNT on all caches apart from the inode cache, since this one is being freed by the generic VFS super_block shrinker. Also set the transaction related caches as SLAB_TEMPORARY, to better document the lifetime of the objects (it just translates to SLAB_RECLAIM_ACCOUNT). Signed-off-by: Nikolay Borisov Reviewed-by: David Sterba Signed-off-by: David Sterba

Merge branch 'cleanups-4.7' into for-chris-4.7-20160525

2016-05-25T20:51:03+00:00

btrfs: fix string and comment grammatical issues and typos

2016-05-25T20:35:14+00:00

Signed-off-by: Nicholas D Steeves Signed-off-by: David Sterba

Btrfs: fix fspath error deallocation

2016-05-10T14:22:26+00:00

Make sure to deallocate fspath with vfree() in case of error in init_ipath(). fspath is allocated with vmalloc() in init_data_container() since commit 425d17a290c0 ("Btrfs: use larger limit for translation of logical to inode"). Signed-off-by: Vincent Stehlé Reviewed-by: David Sterba Signed-off-by: David Sterba

Merge branch 'cleanups-4.6' into for-chris-4.6

2016-02-26T14:38:33+00:00

btrfs: drop null testing before destroy functions

2016-02-18T10:46:03+00:00

Cleanup. kmem_cache_destroy has support NULL argument checking, so drop the double null testing before calling it. Signed-off-by: Kinglong Mee Signed-off-by: David Sterba

btrfs: remove open-coded swap() in backref.c:__merge_refs

2016-02-18T10:45:55+00:00

The kernel provides a swap() that does the same thing as this code. Signed-off-by: Dave Jones Signed-off-by: David Sterba

Btrfs: fix hang on extent buffer lock caused by the inode_paths ioctl

2016-02-05T02:26:25+00:00

While doing some tests I ran into an hang on an extent buffer's rwlock that produced the following trace: [39389.800012] NMI watchdog: BUG: soft lockup - CPU#15 stuck for 22s! [fdm-stress:32166] [39389.800016] NMI watchdog: BUG: soft lockup - CPU#14 stuck for 22s! [fdm-stress:32165] [39389.800016] Modules linked in: btrfs dm_mod ppdev xor sha256_generic hmac raid6_pq drbg ansi_cprng aesni_intel i2c_piix4 acpi_cpufreq aes_x86_64 ablk_helper tpm_tis parport_pc i2c_core sg cryptd evdev psmouse lrw tpm parport gf128mul serio_raw pcspkr glue_helper processor button loop autofs4 ext4 crc16 mbcache jbd2 sd_mod sr_mod cdrom ata_generic virtio_scsi ata_piix libata virtio_pci virtio_ring crc32c_intel scsi_mod e1000 virtio floppy [last unloaded: btrfs] [39389.800016] irq event stamp: 0 [39389.800016] hardirqs last enabled at (0): [< (null)>] (null) [39389.800016] hardirqs last disabled at (0): [] copy_process+0x638/0x1a35 [39389.800016] softirqs last enabled at (0): [] copy_process+0x638/0x1a35 [39389.800016] softirqs last disabled at (0): [< (null)>] (null) [39389.800016] CPU: 14 PID: 32165 Comm: fdm-stress Not tainted 4.4.0-rc6-btrfs-next-18+ #1 [39389.800016] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014 [39389.800016] task: ffff880175b1ca40 ti: ffff8800a185c000 task.ti: ffff8800a185c000 [39389.800016] RIP: 0010:[] [] queued_spin_lock_slowpath+0x57/0x158 [39389.800016] RSP: 0018:ffff8800a185fb80 EFLAGS: 00000202 [39389.800016] RAX: 0000000000000101 RBX: ffff8801710c4e9c RCX: 0000000000000101 [39389.800016] RDX: 0000000000000100 RSI: 0000000000000001 RDI: 0000000000000001 [39389.800016] RBP: ffff8800a185fb98 R08: 0000000000000001 R09: 0000000000000000 [39389.800016] R10: ffff8800a185fb68 R11: 6db6db6db6db6db7 R12: ffff8801710c4e98 [39389.800016] R13: ffff880175b1ca40 R14: ffff8800a185fc10 R15: ffff880175b1ca40 [39389.800016] FS: 00007f6d37fff700(0000) GS:ffff8802be9c0000(0000) knlGS:0000000000000000 [39389.800016] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [39389.800016] CR2: 00007f6d300019b8 CR3: 0000000037c93000 CR4: 00000000001406e0 [39389.800016] Stack: [39389.800016] ffff8801710c4e98 ffff8801710c4e98 ffff880175b1ca40 ffff8800a185fbb0 [39389.800016] ffffffff81091e11 ffff8801710c4e98 ffff8800a185fbc8 ffffffff81091895 [39389.800016] ffff8801710c4e98 ffff8800a185fbe8 ffffffff81486c5c ffffffffa067288c [39389.800016] Call Trace: [39389.800016] [] queued_read_lock_slowpath+0x46/0x60 [39389.800016] [] do_raw_read_lock+0x3e/0x41 [39389.800016] [] _raw_read_lock+0x3d/0x44 [39389.800016] [] ? btrfs_tree_read_lock+0x54/0x125 [btrfs] [39389.800016] [] btrfs_tree_read_lock+0x54/0x125 [btrfs] [39389.800016] [] ? btrfs_find_item+0xa7/0xd2 [btrfs] [39389.800016] [] btrfs_ref_to_path+0xd6/0x174 [btrfs] [39389.800016] [] inode_to_path+0x53/0xa2 [btrfs] [39389.800016] [] paths_from_inode+0x117/0x2ec [btrfs] [39389.800016] [] btrfs_ioctl+0xd5b/0x2793 [btrfs] [39389.800016] [] ? arch_local_irq_save+0x9/0xc [39389.800016] [] ? __this_cpu_preempt_check+0x13/0x15 [39389.800016] [] ? arch_local_irq_save+0x9/0xc [39389.800016] [] ? rcu_read_unlock+0x3e/0x5d [39389.800016] [] do_vfs_ioctl+0x42b/0x4ea [39389.800016] [] ? __fget_light+0x62/0x71 [39389.800016] [] SyS_ioctl+0x57/0x79 [39389.800016] [] entry_SYSCALL_64_fastpath+0x12/0x6f [39389.800016] Code: b9 01 01 00 00 f7 c6 00 ff ff ff 75 32 83 fe 01 89 ca 89 f0 0f 45 d7 f0 0f b1 13 39 f0 74 04 89 c6 eb e2 ff ca 0f 84 fa 00 00 00 <8b> 03 84 c0 74 04 f3 90 eb f6 66 c7 03 01 00 e9 e6 00 00 00 e8 [39389.800012] Modules linked in: btrfs dm_mod ppdev xor sha256_generic hmac raid6_pq drbg ansi_cprng aesni_intel i2c_piix4 acpi_cpufreq aes_x86_64 ablk_helper tpm_tis parport_pc i2c_core sg cryptd evdev psmouse lrw tpm parport gf128mul serio_raw pcspkr glue_helper processor button loop autofs4 ext4 crc16 mbcache jbd2 sd_mod sr_mod cdrom ata_generic virtio_scsi ata_piix libata virtio_pci virtio_ring crc32c_intel scsi_mod e1000 virtio floppy [last unloaded: btrfs] [39389.800012] irq event stamp: 0 [39389.800012] hardirqs last enabled at (0): [< (null)>] (null) [39389.800012] hardirqs last disabled at (0): [] copy_process+0x638/0x1a35 [39389.800012] softirqs last enabled at (0): [] copy_process+0x638/0x1a35 [39389.800012] softirqs last disabled at (0): [< (null)>] (null) [39389.800012] CPU: 15 PID: 32166 Comm: fdm-stress Tainted: G L 4.4.0-rc6-btrfs-next-18+ #1 [39389.800012] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014 [39389.800012] task: ffff880179294380 ti: ffff880034a60000 task.ti: ffff880034a60000 [39389.800012] RIP: 0010:[] [] queued_write_lock_slowpath+0x62/0x72 [39389.800012] RSP: 0018:ffff880034a639f0 EFLAGS: 00000206 [39389.800012] RAX: 0000000000000101 RBX: ffff8801710c4e98 RCX: 0000000000000000 [39389.800012] RDX: 00000000000000ff RSI: 0000000000000000 RDI: ffff8801710c4e9c [39389.800012] RBP: ffff880034a639f8 R08: 0000000000000001 R09: 0000000000000000 [39389.800012] R10: ffff880034a639b0 R11: 0000000000001000 R12: ffff8801710c4e98 [39389.800012] R13: 0000000000000001 R14: ffff880172cbc000 R15: ffff8801710c4e00 [39389.800012] FS: 00007f6d377fe700(0000) GS:ffff8802be9e0000(0000) knlGS:0000000000000000 [39389.800012] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [39389.800012] CR2: 00007f6d3d3c1000 CR3: 0000000037c93000 CR4: 00000000001406e0 [39389.800012] Stack: [39389.800012] ffff8801710c4e98 ffff880034a63a10 ffffffff81091963 ffff8801710c4e98 [39389.800012] ffff880034a63a30 ffffffff81486f1b ffffffffa0672cb3 ffff8801710c4e00 [39389.800012] ffff880034a63a78 ffffffffa0672cb3 ffff8801710c4e00 ffff880034a63a58 [39389.800012] Call Trace: [39389.800012] [] do_raw_write_lock+0x72/0x8c [39389.800012] [] _raw_write_lock+0x3a/0x41 [39389.800012] [] ? btrfs_tree_lock+0x119/0x251 [btrfs] [39389.800012] [] btrfs_tree_lock+0x119/0x251 [btrfs] [39389.800012] [] ? rcu_read_unlock+0x5b/0x5d [btrfs] [39389.800012] [] ? btrfs_root_node+0xda/0xe6 [btrfs] [39389.800012] [] btrfs_lock_root_node+0x22/0x42 [btrfs] [39389.800012] [] btrfs_search_slot+0x1b8/0x758 [btrfs] [39389.800012] [] ? time_hardirqs_on+0x15/0x28 [39389.800012] [] btrfs_lookup_inode+0x31/0x95 [btrfs] [39389.800012] [] ? trace_hardirqs_on+0xd/0xf [39389.800012] [] ? mutex_lock_nested+0x397/0x3bc [39389.800012] [] __btrfs_update_delayed_inode+0x59/0x1c0 [btrfs] [39389.800012] [] __btrfs_commit_inode_delayed_items+0x194/0x5aa [btrfs] [39389.800012] [] ? _raw_spin_unlock+0x31/0x44 [39389.800012] [] __btrfs_run_delayed_items+0xa4/0x15c [btrfs] [39389.800012] [] btrfs_run_delayed_items+0x11/0x13 [btrfs] [39389.800012] [] btrfs_commit_transaction+0x234/0x96e [btrfs] [39389.800012] [] btrfs_sync_fs+0x145/0x1ad [btrfs] [39389.800012] [] btrfs_ioctl+0x11d2/0x2793 [btrfs] [39389.800012] [] ? arch_local_irq_save+0x9/0xc [39389.800012] [] ? __might_fault+0x4c/0xa7 [39389.800012] [] ? __might_fault+0x4c/0xa7 [39389.800012] [] ? arch_local_irq_save+0x9/0xc [39389.800012] [] ? rcu_read_unlock+0x3e/0x5d [39389.800012] [] do_vfs_ioctl+0x42b/0x4ea [39389.800012] [] ? __fget_light+0x62/0x71 [39389.800012] [] SyS_ioctl+0x57/0x79 [39389.800012] [] entry_SYSCALL_64_fastpath+0x12/0x6f [39389.800012] Code: f0 0f b1 13 85 c0 75 ef eb 2a f3 90 8a 03 84 c0 75 f8 f0 0f b0 13 84 c0 75 f0 ba ff 00 00 00 eb 0a f0 0f b1 13 ff c8 74 0b f3 90 <8b> 03 83 f8 01 75 f7 eb ed c6 43 04 00 5b 5d c3 0f 1f 44 00 00 This happens because in the code path executed by the inode_paths ioctl we end up nesting two calls to read lock a leaf's rwlock when after the first call to read_lock() and before the second call to read_lock(), another task (running the delayed items as part of a transaction commit) has already called write_lock() against the leaf's rwlock. This situation is illustrated by the following diagram: Task A Task B btrfs_ref_to_path() btrfs_commit_transaction() read_lock(&eb->lock); btrfs_run_delayed_items() __btrfs_commit_inode_delayed_items() __btrfs_update_delayed_inode() btrfs_lookup_inode() write_lock(&eb->lock); --> task waits for lock read_lock(&eb->lock); --> makes this task hang forever (and task B too of course) So fix this by avoiding doing the nested read lock, which is easily avoidable. This issue does not happen if task B calls write_lock() after task A does the second call to read_lock(), however there does not seem to exist anything in the documentation that mentions what is the expected behaviour for recursive locking of rwlocks (leaving the idea that doing so is not a good usage of rwlocks). Also, as a side effect necessary for this fix, make sure we do not needlessly read lock extent buffers when the input path has skip_locking set (used when called from send). Cc: stable@vger.kernel.org Signed-off-by: Filipe Manana

btrfs: fix iterator with update error in backref.c

2016-01-15T18:27:18+00:00

Fix the following error: fs/btrfs/backref.c:565:1-20: iterator with update on line 577 Fixes: a7ca422('btrfs: use list_for_each_entry* in backref.c') Signed-off-by: Geliang Tang Signed-off-by: David Sterba

lwn.git/fs/btrfs/backref.c, branch 4.8-fixes