Hi all, This is a first pass at improved transaction log reservation overrun reporting based on Dave's suggestion[1]. This essentially creates a new helper to dump transaction info (i.e., logged items) along with ticket data in the event of an overrun and refactors things a bit to be able to call it from a context where an accurate calculation of the reservation requirement is available but the log items have not been removed from the transaction. Note that this increases the amount of output on a tx overrun quite a bit, particularly if the transaction includes multiple log items/vectors, but I opted for verbosity and to retain the current format for the first iteration. I'm curious if anybody has thoughts on formatting, what data to include or not, whether to tie certain things (i.e., raw buffer data?) to the current log level, general level of detail, etc. Sample output from a fabricated overrun is shown below[2]. Lightly tested so far. Thoughts, reviews, flames appreciated. Brian [1] http://www.spinics.net/lists/linux-xfs/msg06446.html [2] Output from an fallocate request after the write transaction reservation is erroneously reduced to 32 bytes: ------------[ cut here ]------------ WARNING: CPU: 1 PID: 1621 at fs/xfs//xfs_log_cil.c:466 xfs_log_commit_cil+0x6d5/0x790 [xfs] ... Call Trace: dump_stack+0x86/0xc3 __warn+0xcb/0xf0 warn_slowpath_null+0x1d/0x20 xfs_log_commit_cil+0x6d5/0x790 [xfs] __xfs_trans_commit+0x82/0x280 [xfs] xfs_trans_commit+0x10/0x20 [xfs] xfs_alloc_file_space+0x22a/0x4c0 [xfs] xfs_file_fallocate+0x230/0x3b0 [xfs] ? rcu_read_lock_sched_held+0x4a/0x80 ? rcu_sync_lockdep_assert+0x2f/0x60 ? __sb_start_write+0xe9/0x210 ? vfs_fallocate+0x214/0x280 vfs_fallocate+0x159/0x280 SyS_fallocate+0x48/0x80 entry_SYSCALL_64_fastpath+0x1f/0xc2 ... ---[ end trace e928d52baa488ea3 ]--- XFS (dm-3): Transaction log reservation overrun: XFS (dm-3): log items: 876 bytes (iov hdrs: 120 bytes) XFS (dm-3): split region headers: 0 bytes XFS (dm-3): ctx ticket: 2100 bytes XFS (dm-3): transaction summary: XFS (dm-3): flags = 0x5 XFS (dm-3): ticket reservation summary: XFS (dm-3): unit res = 2132 bytes XFS (dm-3): current res = -844 bytes XFS (dm-3): total reg = 0 bytes (o/flow = 0 bytes) XFS (dm-3): ophdrs = 0 (ophdr space = 0 bytes) XFS (dm-3): ophdr + reg = 0 bytes XFS (dm-3): num regions = 0 XFS (dm-3): log item: XFS (dm-3): type = 0x123b XFS (dm-3): flags = 0x1 XFS (dm-3): niovecs = 4 XFS (dm-3): size = 720 XFS (dm-3): bytes = 300 XFS (dm-3): buf len = 304 XFS (dm-3): iovec[0] XFS (dm-3): type = 0x5 XFS (dm-3): len = 56 XFS (dm-3): first 32 bytes of iovec[0]: ffff984954ea2c78: 3b 12 04 00 45 00 00 00 34 00 10 00 49 98 ff ff ;...E...4...I... ffff984954ea2c88: 63 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 c............... XFS (dm-3): iovec[1] XFS (dm-3): type = 0x6 XFS (dm-3): len = 176 XFS (dm-3): first 32 bytes of iovec[1]: ffff984954ea2cb0: 4e 49 a4 81 03 02 00 00 00 00 00 00 00 00 00 00 NI.............. ffff984954ea2cc0: 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ XFS (dm-3): iovec[2] XFS (dm-3): type = 0x7 XFS (dm-3): len = 16 XFS (dm-3): first 16 bytes of iovec[2]: ffff984954ea2d60: 80 00 00 00 00 00 00 00 00 00 00 00 02 80 01 00 ................ XFS (dm-3): iovec[3] XFS (dm-3): type = 0xc XFS (dm-3): len = 52 XFS (dm-3): first 32 bytes of iovec[3]: ffff984954ea2d70: 00 33 01 00 07 25 04 73 65 6c 69 6e 75 78 75 6e .3...%.selinuxun ffff984954ea2d80: 63 6f 6e 66 69 6e 65 64 5f 75 3a 6f 62 6a 65 63 confined_u:objec XFS (dm-3): log item: XFS (dm-3): type = 0x123c XFS (dm-3): flags = 0x0 XFS (dm-3): niovecs = 2 XFS (dm-3): size = 256 XFS (dm-3): bytes = 152 XFS (dm-3): buf len = 152 XFS (dm-3): iovec[0] XFS (dm-3): type = 0x1 XFS (dm-3): len = 24 XFS (dm-3): first 24 bytes of iovec[0]: ffff9849532d1258: 3c 12 02 00 00 28 01 00 01 00 00 00 00 00 00 00 <....(.......... ffff9849532d1268: 01 00 00 00 01 00 00 00 ........ XFS (dm-3): iovec[1] XFS (dm-3): type = 0x2 XFS (dm-3): len = 128 XFS (dm-3): first 32 bytes of iovec[1]: ffff9849532d1270: 58 41 47 46 00 00 00 01 00 00 00 00 00 0f 00 00 XAGF............ ffff9849532d1280: 00 00 00 01 00 00 00 02 00 00 00 00 00 00 00 01 ................ XFS (dm-3): log item: XFS (dm-3): type = 0x123c XFS (dm-3): flags = 0x0 XFS (dm-3): niovecs = 2 XFS (dm-3): size = 256 XFS (dm-3): bytes = 152 XFS (dm-3): buf len = 152 XFS (dm-3): iovec[0] XFS (dm-3): type = 0x1 XFS (dm-3): len = 24 XFS (dm-3): first 24 bytes of iovec[0]: ffff9849532d1358: 3c 12 02 00 00 20 08 00 10 00 00 00 00 00 00 00 <.... .......... ffff9849532d1368: 01 00 00 00 01 00 00 00 ........ XFS (dm-3): iovec[1] XFS (dm-3): type = 0x2 XFS (dm-3): len = 128 XFS (dm-3): first 32 bytes of iovec[1]: ffff9849532d1370: 41 42 33 43 00 00 00 02 ff ff ff ff ff ff ff ff AB3C............ ffff9849532d1380: 00 00 00 00 00 00 00 10 00 00 00 01 00 00 00 54 ...............T XFS (dm-3): log item: XFS (dm-3): type = 0x123c XFS (dm-3): flags = 0x0 XFS (dm-3): niovecs = 2 XFS (dm-3): size = 256 XFS (dm-3): bytes = 152 XFS (dm-3): buf len = 152 XFS (dm-3): iovec[0] XFS (dm-3): type = 0x1 XFS (dm-3): len = 24 XFS (dm-3): first 24 bytes of iovec[0]: ffff9849532d1558: 3c 12 02 00 00 20 08 00 08 00 00 00 00 00 00 00 <.... .......... ffff9849532d1568: 01 00 00 00 01 00 00 00 ........ XFS (dm-3): iovec[1] XFS (dm-3): type = 0x2 XFS (dm-3): len = 128 XFS (dm-3): first 32 bytes of iovec[1]: ffff9849532d1570: 41 42 33 42 00 00 00 02 ff ff ff ff ff ff ff ff AB3B............ ffff9849532d1580: 00 00 00 00 00 00 00 08 00 00 00 01 00 00 00 54 ...............T XFS (dm-3): xfs_do_force_shutdown(0x2) called from line 501 of file fs/xfs//xfs_log_cil.c. Return address = 0xffffffffc041e56b XFS (dm-3): Log I/O Error Detected. Shutting down filesystem XFS (dm-3): Please umount the filesystem and rectify the problem(s) Brian Foster (3): xfs: separate shutdown from ticket reservation print helper xfs: refactor xlog_cil_insert_items() to facilitate transaction dump xfs: dump transaction usage details on log reservation overrun fs/xfs/xfs_log.c | 59 +++++++++++++++++++++++++++++++++--- fs/xfs/xfs_log_cil.c | 84 ++++++++++++++++++++++++++++++--------------------- fs/xfs/xfs_log_priv.h | 1 + 3 files changed, 105 insertions(+), 39 deletions(-) -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
