- 27 Jul, 2020 40 commits
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Qu Wenruo authored
[BUG] When the anonymous block device pool is exhausted, subvolume/snapshot creation fails with EMFILE (Too many files open). This has been reported by a user. The allocation happens in the second phase during transaction commit where it's only way out is to abort the transaction BTRFS: Transaction aborted (error -24) WARNING: CPU: 17 PID: 17041 at fs/btrfs/transaction.c:1576 create_pending_snapshot+0xbc4/0xd10 [btrfs] RIP: 0010:create_pending_snapshot+0xbc4/0xd10 [btrfs] Call Trace: create_pending_snapshots+0x82/0xa0 [btrfs] btrfs_commit_transaction+0x275/0x8c0 [btrfs] btrfs_mksubvol+0x4b9/0x500 [btrfs] btrfs_ioctl_snap_create_transid+0x174/0x180 [btrfs] btrfs_ioctl_snap_create_v2+0x11c/0x180 [btrfs] btrfs_ioctl+0x11a4/0x2da0 [btrfs] do_vfs_ioctl+0xa9/0x640 ksys_ioctl+0x67/0x90 __x64_sys_ioctl+0x1a/0x20 do_syscall_64+0x5a/0x110 entry_SYSCALL_64_after_hwframe+0x44/0xa9 ---[ end trace 33f2f83f3d5250e9 ]--- BTRFS: error (device sda1) in create_pending_snapshot:1576: errno=-24 unknown BTRFS info (device sda1): forced readonly BTRFS warning (device sda1): Skipping commit of aborted transaction. BTRFS: error (device sda1) in cleanup_transaction:1831: errno=-24 unknown [CAUSE] When the global anonymous block device pool is exhausted, the following call chain will fail, and lead to transaction abort: btrfs_ioctl_snap_create_v2() |- btrfs_ioctl_snap_create_transid() |- btrfs_mksubvol() |- btrfs_commit_transaction() |- create_pending_snapshot() |- btrfs_get_fs_root() |- btrfs_init_fs_root() |- get_anon_bdev() [FIX] Although we can't enlarge the anonymous block device pool, at least we can preallocate anon_dev for subvolume/snapshot in the first phase, outside of transaction context and exactly at the moment the user calls the creation ioctl. Reported-by:Greed Rong <greedrong@gmail.com> Link: https://lore.kernel.org/linux-btrfs/CA+UqX+NTrZ6boGnWHhSeZmEY5J76CTqmYjO2S+=tHJX7nb9DPw@mail.gmail.com/ CC: stable@vger.kernel.org # 4.4+ Signed-off-by:
Qu Wenruo <wqu@suse.com> Reviewed-by:
David Sterba <dsterba@suse.com> Signed-off-by:
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Qu Wenruo authored
[BUG] When a lot of subvolumes are created, there is a user report about transaction aborted caused by slow anonymous block device reclaim: BTRFS: Transaction aborted (error -24) WARNING: CPU: 17 PID: 17041 at fs/btrfs/transaction.c:1576 create_pending_snapshot+0xbc4/0xd10 [btrfs] RIP: 0010:create_pending_snapshot+0xbc4/0xd10 [btrfs] Call Trace: create_pending_snapshots+0x82/0xa0 [btrfs] btrfs_commit_transaction+0x275/0x8c0 [btrfs] btrfs_mksubvol+0x4b9/0x500 [btrfs] btrfs_ioctl_snap_create_transid+0x174/0x180 [btrfs] btrfs_ioctl_snap_create_v2+0x11c/0x180 [btrfs] btrfs_ioctl+0x11a4/0x2da0 [btrfs] do_vfs_ioctl+0xa9/0x640 ksys_ioctl+0x67/0x90 __x64_sys_ioctl+0x1a/0x20 do_syscall_64+0x5a/0x110 entry_SYSCALL_64_after_hwframe+0x44/0xa9 ---[ end trace 33f2f83f3d5250e9 ]--- BTRFS: error (device sda1) in create_pending_snapshot:1576: errno=-24 unknown BTRFS info (device sda1): forced readonly BTRFS warning (device sda1): Skipping commit of aborted transaction. BTRFS: error (device sda1) in cleanup_transaction:1831: errno=-24 unknown [CAUSE] The anonymous device pool is shared and its size is 1M. It's possible to hit that limit if the subvolume deletion is not fast enough and the subvolumes to be cleaned keep the ids allocated. [WORKAROUND] We can't avoid the anon device pool exhaustion but we can shorten the time the id is attached to the subvolume root once the subvolume becomes invisible to the user. Reported-by:
Josef Bacik <josef@toxicpanda.com> Signed-off-by:
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Qu Wenruo authored
[BUG] When a lot of subvolumes are created, there is a user report about transaction aborted: BTRFS: Transaction aborted (error -24) WARNING: CPU: 17 PID: 17041 at fs/btrfs/transaction.c:1576 create_pending_snapshot+0xbc4/0xd10 [btrfs] RIP: 0010:create_pending_snapshot+0xbc4/0xd10 [btrfs] Call Trace: create_pending_snapshots+0x82/0xa0 [btrfs] btrfs_commit_transaction+0x275/0x8c0 [btrfs] btrfs_mksubvol+0x4b9/0x500 [btrfs] btrfs_ioctl_snap_create_transid+0x174/0x180 [btrfs] btrfs_ioctl_snap_create_v2+0x11c/0x180 [btrfs] btrfs_ioctl+0x11a4/0x2da0 [btrfs] do_vfs_ioctl+0xa9/0x640 ksys_ioctl+0x67/0x90 __x64_sys_ioctl+0x1a/0x20 do_syscall_64+0x5a/0x110 entry_SYSCALL_64_after_hwframe+0x44/0xa9 ---[ end trace 33f2f83f3d5250e9 ]--- BTRFS: error (device sda1) in create_pending_snapshot:1576: errno=-24 unknown BTRFS info (device sda1): forced readonly BTRFS warning (device sda1): Skipping commit of aborted transaction. BTRFS: error (device sda1) in cleanup_transaction:1831: errno=-24 unknown [CAUSE] The error is EMFILE (Too many files open) and comes from the anonymous block device allocation. The ids are in a shared pool of size 1<<20. The ids are assigned to live subvolumes, ie. the root structure exists in memory (eg. after creation or after the root appears in some path). The pool could be exhausted if the numbers are not reclaimed fast enough, after subvolume deletion or if other system component uses the anon block devices. [WORKAROUND] Since it's not possible to completely solve the problem, we can only minimize the time the id is allocated to a subvolume root. Firstly, we can reduce the use of anon_dev by trees that are not subvolume roots, like data reloc tree. This patch will do extra check on root objectid, to skip roots that don't need anon_dev. Currently it's only data reloc tree and orphan roots. Reported-by:
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Qu Wenruo authored
This patch will add the following sysfs interface: /sys/fs/btrfs/<UUID>/qgroups/<qgroup_id>/referenced /sys/fs/btrfs/<UUID>/qgroups/<qgroup_id>/exclusive /sys/fs/btrfs/<UUID>/qgroups/<qgroup_id>/max_referenced /sys/fs/btrfs/<UUID>/qgroups/<qgroup_id>/max_exclusive /sys/fs/btrfs/<UUID>/qgroups/<qgroup_id>/limit_flags Which is also available in output of "btrfs qgroup show". /sys/fs/btrfs/<UUID>/qgroups/<qgroup_id>/rsv_data /sys/fs/btrfs/<UUID>/qgroups/<qgroup_id>/rsv_meta_pertrans /sys/fs/btrfs/<UUID>/qgroups/<qgroup_id>/rsv_meta_prealloc The last 3 rsv related members are not visible to users, but can be very useful to debug qgroup limit related bugs. Also, to avoid '/' used in <qgroup_id>, the separator between qgroup level and qgroup id is changed to '_'. The interface is not hidden behind 'debug' as we want this interface to be included into production build and to provide another way to read the qgroup information besides the ioctls. Signed-off-by:
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Qu Wenruo authored
The qgroup level is limited to u16, so no need to use u64 for it. Signed-off-by:
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Nikolay Borisov authored
vfs_inode is used only for the inode number everything else requires btrfs_inode. Signed-off-by:
Nikolay Borisov <nborisov@suse.com> Reviewed-by:
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Nikolay Borisov authored
Instead of making multiple calls to BTRFS_I simply take btrfs_inode as an input paramter. Signed-off-by:
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Nikolay Borisov authored
The vfs inode is only used for a pair of inode_lock/unlock calls all other uses call for btrfs_inode. Signed-off-by:
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Nikolay Borisov authored
All of its children functions use btrfs_inode. Signed-off-by:
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Nikolay Borisov authored
All of its children take btrfs_inode so bubble up this requirement to btrfs_delalloc_reserve_space's interface and stop calling BTRFS_I internally. Signed-off-by:
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Nikolay Borisov authored
Instead of calling BTRFS_I on the passed vfs_inode take btrfs_inode directly. Signed-off-by:
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Nikolay Borisov authored
It needs btrfs_inode so take it as a parameter directly. Signed-off-by:
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Nikolay Borisov authored
It only uses btrfs_inode internally so take it as a parameter. Signed-off-by:
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Nikolay Borisov authored
No point in taking an inode only to get btrfs_fs_info from it, instead take btrfs_fs_info directly. Signed-off-by:
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Nikolay Borisov authored
There's only a single use of vfs_inode in a tracepoint so let's take btrfs_inode directly. Signed-off-by:
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Nikolay Borisov authored
There is a single use of the generic vfs_inode so let's take btrfs_inode as a parameter and remove couple of redundant BTRFS_I() calls. Signed-off-by:
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Nikolay Borisov authored
Preparation to make btrfs_dirty_pages take btrfs_inode as parameter. Signed-off-by:
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Nikolay Borisov authored
Only find_lock_delalloc_range uses vfs_inode so let's take the btrfs_inode as a parameter. Signed-off-by:
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Nikolay Borisov authored
It has only a single use for a generic vfs inode vs 3 for btrfs_inode. Signed-off-by:
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Nikolay Borisov authored
This function really needs a btrfs_inode and not a generic vfs one. Take it as a parameter and get rid of superfluous BTRFS_I() calls. Signed-off-by:
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Nikolay Borisov authored
Take btrfs_inode directly and stop using superfulous BTRFS_I calls. Signed-off-by:
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Nikolay Borisov authored
Simply forwards its argument so let's get rid of one extra BTRFS_I by taking btrfs_inode directly. Signed-off-by:
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Nikolay Borisov authored
All children now take btrfs_inode so convert it to taking it as a parameter as well. Signed-off-by:
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Nikolay Borisov authored
Gets rid of superfulous BTRFS_I() calls and prepare for converting btrfs_run_delalloc_range to using btrfs_inode. Signed-off-by:
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Nikolay Borisov authored
Simply gets rid of superfluous BTRFS_I() calls. Signed-off-by:
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Nikolay Borisov authored
Gets rid of superfluous BTRFS_I() calls. Signed-off-by:
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Nikolay Borisov authored
Preparation to converting btrfs_run_delalloc_range to using btrfs_inode without BTRFS_I() calls. Signed-off-by:
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Nikolay Borisov authored
It really wants btrfs_inode. Signed-off-by:
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Nikolay Borisov authored
It doesn't really need vfs_inode but btrfs_inode. Signed-off-by:
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Nikolay Borisov authored
It only uses vfs inode for assigning it to the async_chunk function. Signed-off-by:
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Nikolay Borisov authored
It only really uses btrfs_inode. Signed-off-by:
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Nikolay Borisov authored
It really wants btrfs_inode and is prepration to converting run_delalloc_nocow to taking btrfs_inode. Signed-off-by:
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Nikolay Borisov authored
Signed-off-by:
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Nikolay Borisov authored
It just forwards its argument to __btrfs_qgroup_release_data. Signed-off-by:
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Nikolay Borisov authored
All but 3 uses require vfs_inode so convert the logic to have btrfs_inode be the main inode struct. Signed-off-by:
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Nikolay Borisov authored
Majority of its uses are for btrfs_inode so take it as an argument directly. Signed-off-by:
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Nikolay Borisov authored
It simpy forwards its inode argument to __btrfs_add_ordered_extent which already takes btrfs_inode. Signed-off-by:
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Nikolay Borisov authored
All its children functions take btrfs_inode so convert it to taking btrfs_inode. Signed-off-by:
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Nikolay Borisov authored
Preparation to converting its callers to taking btrfs_inode. Signed-off-by:
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Nikolay Borisov authored
It has only 2 uses for the vfs_inode - insert_inline_extent and i_size_read. On the flipside it will allow converting its callers to btrfs_inode, so convert it to taking btrfs_inode. Signed-off-by:
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