On Wed, Oct 02, 2019 at 02:58:55PM +0200, David Sterba wrote: > On Fri, Sep 06, 2019 at 10:15:30AM -0700, Mark Fasheh wrote: > > Hi, > > > > Relocation caches extent backrefs in an rbtree (the 'backref cache'). The > > following patches move the backref cache code out of relocation.c and into > > it's own file. We then do a straight-forward cleanup the main backref cache > > function, build_backref_tree(). No functionality is changed in these > > patches. > > > > These patches are part of a larger series I have, which speeds up qgroup > > accounting by using the same backref cache facility. That series is not > > quite ready, however I wanted to see about getting these cleanup patches > > upstreamed as they are nicely self contained and benefit the readability of > > the code. > > Patches 1-3 moved to misc-next.
And removed again. There's an assertion hit in at least 2 fstests (btrfs/061, btrfs/063, btrfs/187). I tried the verbatim patches from the mailinglist and the version I applied with some minor edits, both reproduce that. [ 6466.460371] assertion failed: !node || !node->detached, in fs/btrfs/backref-cache.c:890 [ 6466.462933] ------------[ cut here ]------------ [ 6466.464419] kernel BUG at fs/btrfs/ctree.h:3119! [ 6466.465950] invalid opcode: 0000 [#1] SMP [ 6466.467281] CPU: 3 PID: 23411 Comm: btrfs Tainted: G W 5.4.0-rc1-default+ #743 [ 6466.470089] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58-prebuilt.qemu.org 04/01/2014 [ 6466.473501] RIP: 0010:assfail.constprop.0+0x18/0x26 [btrfs] [ 6466.479151] RSP: 0000:ffffaca387a13950 EFLAGS: 00010246 [ 6466.479965] RAX: 000000000000004b RBX: ffff97d4777aacb8 RCX: 0000000000000001 [ 6466.481011] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffffbd1044c0 [ 6466.482059] RBP: dead000000000122 R08: 0000000000000000 R09: 0000000000000000 [ 6466.483114] R10: 0000000000000000 R11: 0000000000000000 R12: dead000000000100 [ 6466.484163] R13: ffff97d46d38f508 R14: ffff97d490a74b90 R15: ffff97d4777aace8 [ 6466.485236] FS: 00007f5ca43fb8c0(0000) GS:ffff97d4bdc00000(0000) knlGS:0000000000000000 [ 6466.486508] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 6466.487888] CR2: 000055c2028b0018 CR3: 000000003abfe000 CR4: 00000000000006e0 [ 6466.489924] Call Trace: [ 6466.490728] build_backref_tree.cold+0xcc/0xdd [btrfs] [ 6466.492400] relocate_tree_blocks+0x19c/0x6f0 [btrfs] [ 6466.493989] ? kmem_cache_alloc_trace+0x1d3/0x260 [ 6466.495405] relocate_block_group+0x218/0x5b0 [btrfs] [ 6466.496884] btrfs_relocate_block_group+0x154/0x300 [btrfs] [ 6466.498478] btrfs_relocate_chunk+0x32/0xd0 [btrfs] [ 6466.499768] __btrfs_balance+0x41c/0xc90 [btrfs] [ 6466.501306] btrfs_balance+0x57d/0xa60 [btrfs] [ 6466.502663] ? btrfs_ioctl_balance+0x21c/0x350 [btrfs] [ 6466.504183] ? kmem_cache_alloc_trace+0x1d3/0x260 [ 6466.505578] btrfs_ioctl_balance+0x298/0x350 [btrfs] [ 6466.506819] btrfs_ioctl+0x2d3/0x2550 [btrfs] [ 6466.507964] ? __handle_mm_fault+0x60b/0x6e0 [ 6466.508883] ? _raw_spin_unlock+0x24/0x30 [ 6466.509678] ? do_vfs_ioctl+0x405/0x730 [ 6466.510390] do_vfs_ioctl+0x405/0x730 [ 6466.511056] ksys_ioctl+0x3a/0x70 [ 6466.511834] ? trace_hardirqs_off_thunk+0x1a/0x20 [ 6466.512715] __x64_sys_ioctl+0x16/0x20 [ 6466.513351] do_syscall_64+0x50/0x1f0 [ 6466.513978] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 6466.514790] RIP: 0033:0x7f5ca4620387 [ 6466.518949] RSP: 002b:00007ffe004aeb78 EFLAGS: 00000206 ORIG_RAX: 0000000000000010 [ 6466.521066] RAX: ffffffffffffffda RBX: 00007ffe004aec20 RCX: 00007f5ca4620387 [ 6466.523018] RDX: 00007ffe004aec20 RSI: 00000000c4009420 RDI: 0000000000000003 [ 6466.524988] RBP: 0000000000000003 R08: 000055683637c2a0 R09: 0000000000000231 [ 6466.526966] R10: fffffffffffff206 R11: 0000000000000206 R12: 0000000000000001 [ 6466.528936] R13: 00007ffe004b0167 R14: 0000000000000001 R15: 0000000000000000 [ 6466.533252] Modules linked in: dm_flakey dm_mod dax btrfs libcrc32c xor zstd_decompress zstd_compress xxhash raid6_pq loop [ 6466.535241] ---[ end trace a30d87f8f65c9956 ]--- [ 6466.536313] RIP: 0010:assfail.constprop.0+0x18/0x26 [btrfs] [ 6466.540357] RSP: 0000:ffffaca387a13950 EFLAGS: 00010246 [ 6466.541358] RAX: 000000000000004b RBX: ffff97d4777aacb8 RCX: 0000000000000001 [ 6466.542609] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffffbd1044c0 [ 6466.545863] RBP: dead000000000122 R08: 0000000000000000 R09: 0000000000000000 [ 6466.548036] R10: 0000000000000000 R11: 0000000000000000 R12: dead000000000100 [ 6466.549618] R13: ffff97d46d38f508 R14: ffff97d490a74b90 R15: ffff97d4777aace8 [ 6466.551137] FS: 00007f5ca43fb8c0(0000) GS:ffff97d4bdc00000(0000) knlGS:0000000000000000 [ 6466.552858] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 6466.553844] CR2: 000055c2028b0018 CR3: 000000003abfe000 CR4: 00000000000006e0 [ 6467.928233] ------------[ cut here ]------------
