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/ctree.h | 6 ++++-- fs/btrfs/space-info.c | 31 ++++++++++++++++++++++++------- fs/btrfs/space-info.h | 2 ++ fs/btrfs/super.c | 4 +++- 4 files changed, 33 insertions(+), 10 deletions(-) diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 5d03fc267b58..b38cd6e2eb5d 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -3828,7 +3828,7 @@ const char * __attribute_const__ btrfs_decode_error(int errno); __cold void __btrfs_abort_transaction(struct btrfs_trans_handle *trans, const char *function, - unsigned int line, int errno); + unsigned int line, int errno, bool first_hit); /* * Call btrfs_abort_transaction as early as possible when an error condition is @@ -3836,9 +3836,11 @@ void __btrfs_abort_transaction(struct btrfs_trans_handle *trans, */ #define btrfs_abort_transaction(trans, errno) \ do { \ + bool first = false; \ /* Report first abort since mount */ \ if (!test_and_set_bit(BTRFS_FS_STATE_TRANS_ABORTED, \ &((trans)->fs_info->fs_state))) { \ + first = true; \ if ((errno) != -EIO && (errno) != -EROFS) { \ WARN(1, KERN_DEBUG \ "BTRFS: Transaction aborted (error %d)\n", \ @@ -3850,7 +3852,7 @@ do { \ } \ } \ __btrfs_abort_transaction((trans), __func__, \ - __LINE__, (errno)); \ + __LINE__, (errno), first); \ } while (0) #ifdef CONFIG_PRINTK_INDEX diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c index 3527276f35e9..2e06b7c422c7 100644 --- a/fs/btrfs/space-info.c +++ b/fs/btrfs/space-info.c @@ -492,6 +492,15 @@ static const char *space_info_flag_to_str(const struct btrfs_space_info *space_i } } +static void dump_global_block_rsv(struct btrfs_fs_info *fs_info) +{ + DUMP_BLOCK_RSV(fs_info, global_block_rsv); + DUMP_BLOCK_RSV(fs_info, trans_block_rsv); + DUMP_BLOCK_RSV(fs_info, chunk_block_rsv); + DUMP_BLOCK_RSV(fs_info, delayed_block_rsv); + DUMP_BLOCK_RSV(fs_info, delayed_refs_rsv); +} + static void __btrfs_dump_space_info(struct btrfs_fs_info *fs_info, struct btrfs_space_info *info) { @@ -508,13 +517,6 @@ static void __btrfs_dump_space_info(struct btrfs_fs_info *fs_info, info->total_bytes, info->bytes_used, info->bytes_pinned, info->bytes_reserved, info->bytes_may_use, info->bytes_readonly, info->bytes_zone_unusable); - - DUMP_BLOCK_RSV(fs_info, global_block_rsv); - DUMP_BLOCK_RSV(fs_info, trans_block_rsv); - DUMP_BLOCK_RSV(fs_info, chunk_block_rsv); - DUMP_BLOCK_RSV(fs_info, delayed_block_rsv); - DUMP_BLOCK_RSV(fs_info, delayed_refs_rsv); - } void btrfs_dump_space_info(struct btrfs_fs_info *fs_info, @@ -526,6 +528,7 @@ void btrfs_dump_space_info(struct btrfs_fs_info *fs_info, spin_lock(&info->lock); __btrfs_dump_space_info(fs_info, info); + dump_global_block_rsv(fs_info); spin_unlock(&info->lock); if (!dump_block_groups) @@ -1770,3 +1773,17 @@ int btrfs_reserve_data_bytes(struct btrfs_fs_info *fs_info, u64 bytes, } return ret; } + +/* Dump all the space infos when we abort a transaction due to ENOSPC. */ +__cold void btrfs_dump_space_info_for_trans_abort(struct btrfs_fs_info *fs_info) +{ + struct btrfs_space_info *space_info; + + btrfs_info(fs_info, "dumping space info:"); + list_for_each_entry(space_info, &fs_info->space_info, list) { + spin_lock(&space_info->lock); + __btrfs_dump_space_info(fs_info, space_info); + spin_unlock(&space_info->lock); + } + dump_global_block_rsv(fs_info); +} 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 */ diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 51449619a023..7291e9d67e92 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -346,12 +346,14 @@ void __cold btrfs_err_32bit_limit(struct btrfs_fs_info *fs_info) __cold void __btrfs_abort_transaction(struct btrfs_trans_handle *trans, const char *function, - unsigned int line, int errno) + unsigned int line, int errno, bool first_hit) { struct btrfs_fs_info *fs_info = trans->fs_info; WRITE_ONCE(trans->aborted, errno); WRITE_ONCE(trans->transaction->aborted, errno); + if (first_hit && errno == -ENOSPC) + btrfs_dump_space_info_for_trans_abort(fs_info); /* Wake up anybody who may be waiting on this transaction */ wake_up(&fs_info->transaction_wait); wake_up(&fs_info->transaction_blocked_wait); -- cgit v1.2.3