From 8e327b9c0de858f27e711f854e8bf99e5d409c2e Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Thu, 25 Aug 2022 15:09:10 +0800 Subject: btrfs: dump all space infos if we abort transaction due to ENOSPC We have hit some transaction abort due to -ENOSPC internally. Normally we should always reserve enough space for metadata for every transaction, thus hitting -ENOSPC should really indicate some cases we didn't expect. But unfortunately current error reporting will only give a kernel warning and stack trace, not really helpful to debug what's causing the problem. And mount option debug_enospc can only help when user can reproduce the problem, but under most cases, such transaction abort by -ENOSPC is really hard to reproduce. So this patch will dump all space infos (data, metadata, system) when we abort the first transaction with -ENOSPC. This should at least provide some clue to us. The example of a dump would look like this: BTRFS: Transaction aborted (error -28) WARNING: CPU: 8 PID: 3366 at fs/btrfs/transaction.c:2137 btrfs_commit_transaction+0xf81/0xfb0 [btrfs] ---[ end trace 0000000000000000 ]--- BTRFS info (device dm-1: state A): dumping space info: BTRFS info (device dm-1: state A): space_info DATA has 6791168 free, is not full BTRFS info (device dm-1: state A): space_info total=8388608, used=1597440, pinned=0, reserved=0, may_use=0, readonly=0 zone_unusable=0 BTRFS info (device dm-1: state A): space_info METADATA has 257114112 free, is not full BTRFS info (device dm-1: state A): space_info total=268435456, used=131072, pinned=180224, reserved=65536, may_use=10878976, readonly=65536 zone_unusable=0 BTRFS info (device dm-1: state A): space_info SYSTEM has 8372224 free, is not full BTRFS info (device dm-1: state A): space_info total=8388608, used=16384, pinned=0, reserved=0, may_use=0, readonly=0 zone_unusable=0 BTRFS info (device dm-1: state A): global_block_rsv: size 3670016 reserved 3670016 BTRFS info (device dm-1: state A): trans_block_rsv: size 0 reserved 0 BTRFS info (device dm-1: state A): chunk_block_rsv: size 0 reserved 0 BTRFS info (device dm-1: state A): delayed_block_rsv: size 4063232 reserved 4063232 BTRFS info (device dm-1: state A): delayed_refs_rsv: size 3145728 reserved 3145728 BTRFS: error (device dm-1: state A) in btrfs_commit_transaction:2137: errno=-28 No space left BTRFS info (device dm-1: state EA): forced readonly Reviewed-by: Johannes Thumshirn Signed-off-by: Qu Wenruo Signed-off-by: David Sterba --- fs/btrfs/space-info.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'fs/btrfs/space-info.h') diff --git a/fs/btrfs/space-info.h b/fs/btrfs/space-info.h index 2039096803ed..8f5948740941 100644 --- a/fs/btrfs/space-info.h +++ b/fs/btrfs/space-info.h @@ -157,4 +157,6 @@ static inline void btrfs_space_info_free_bytes_may_use( } int btrfs_reserve_data_bytes(struct btrfs_fs_info *fs_info, u64 bytes, enum btrfs_reserve_flush_enum flush); +void btrfs_dump_space_info_for_trans_abort(struct btrfs_fs_info *fs_info); + #endif /* BTRFS_SPACE_INFO_H */ -- cgit v1.2.3-70-g09d2