forked from luck/tmp_suning_uos_patched
27fb5a72f5
I noticed that fsfreeze can take a very long time to freeze an XFS if there happens to be a GETFSMAP caller running in the background. I also happened to notice the following in dmesg: ------------[ cut here ]------------ WARNING: CPU: 2 PID: 43492 at fs/xfs/xfs_super.c:853 xfs_quiesce_attr+0x83/0x90 [xfs] Modules linked in: xfs libcrc32c ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 ip_set_hash_ip ip_set_hash_net xt_tcpudp xt_set ip_set_hash_mac ip_set nfnetlink ip6table_filter ip6_tables bfq iptable_filter sch_fq_codel ip_tables x_tables nfsv4 af_packet [last unloaded: xfs] CPU: 2 PID: 43492 Comm: xfs_io Not tainted 5.6.0-rc4-djw #rc4 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.10.2-1ubuntu1 04/01/2014 RIP: 0010:xfs_quiesce_attr+0x83/0x90 [xfs] Code: 7c 07 00 00 85 c0 75 22 48 89 df 5b e9 96 c1 00 00 48 c7 c6 b0 2d 38 a0 48 89 df e8 57 64 ff ff 8b 83 7c 07 00 00 85 c0 74 de <0f> 0b 48 89 df 5b e9 72 c1 00 00 66 90 0f 1f 44 00 00 41 55 41 54 RSP: 0018:ffffc900030f3e28 EFLAGS: 00010202 RAX: 0000000000000001 RBX: ffff88802ac54000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff81e4a6f0 RDI: 00000000ffffffff RBP: ffff88807859f070 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000010 R12: 0000000000000000 R13: ffff88807859f388 R14: ffff88807859f4b8 R15: ffff88807859f5e8 FS: 00007fad1c6c0fc0(0000) GS:ffff88807e000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0c7d237000 CR3: 0000000077f01003 CR4: 00000000001606a0 Call Trace: xfs_fs_freeze+0x25/0x40 [xfs] freeze_super+0xc8/0x180 do_vfs_ioctl+0x70b/0x750 ? __fget_files+0x135/0x210 ksys_ioctl+0x3a/0xb0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x50/0x1a0 entry_SYSCALL_64_after_hwframe+0x49/0xbe These two things appear to be related. The assertion trips when another thread initiates a fsmap request (which uses an empty transaction) after the freezer waited for m_active_trans to hit zero but before the the freezer executes the WARN_ON just prior to calling xfs_log_quiesce. The lengthy delays in freezing happen because the freezer calls xfs_wait_buftarg to clean out the buffer lru list. Meanwhile, the GETFSMAP caller is continuing to grab and release buffers, which means that it can take a very long time for the buffer lru list to empty out. We fix both of these races by calling sb_start_write to obtain freeze protection while using empty transactions for GETFSMAP and for metadata scrubbing. The other two users occur during mount, during which time we cannot fs freeze. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> |
||
|---|---|---|
| .. | ||
| libxfs | ||
| scrub | ||
| Kconfig | ||
| kmem.c | ||
| kmem.h | ||
| Makefile | ||
| mrlock.h | ||
| xfs_acl.c | ||
| xfs_acl.h | ||
| xfs_aops.c | ||
| xfs_aops.h | ||
| xfs_attr_inactive.c | ||
| xfs_attr_list.c | ||
| xfs_bio_io.c | ||
| xfs_bmap_item.c | ||
| xfs_bmap_item.h | ||
| xfs_bmap_util.c | ||
| xfs_bmap_util.h | ||
| xfs_buf_item.c | ||
| xfs_buf_item.h | ||
| xfs_buf.c | ||
| xfs_buf.h | ||
| xfs_dir2_readdir.c | ||
| xfs_discard.c | ||
| xfs_discard.h | ||
| xfs_dquot_item.c | ||
| xfs_dquot_item.h | ||
| xfs_dquot.c | ||
| xfs_dquot.h | ||
| xfs_error.c | ||
| xfs_error.h | ||
| xfs_export.c | ||
| xfs_export.h | ||
| xfs_extent_busy.c | ||
| xfs_extent_busy.h | ||
| xfs_extfree_item.c | ||
| xfs_extfree_item.h | ||
| xfs_file.c | ||
| xfs_filestream.c | ||
| xfs_filestream.h | ||
| xfs_fsmap.c | ||
| xfs_fsmap.h | ||
| xfs_fsops.c | ||
| xfs_fsops.h | ||
| xfs_globals.c | ||
| xfs_health.c | ||
| xfs_icache.c | ||
| xfs_icache.h | ||
| xfs_icreate_item.c | ||
| xfs_icreate_item.h | ||
| xfs_inode_item.c | ||
| xfs_inode_item.h | ||
| xfs_inode.c | ||
| xfs_inode.h | ||
| xfs_ioctl.c | ||
| xfs_ioctl.h | ||
| xfs_ioctl32.c | ||
| xfs_ioctl32.h | ||
| xfs_iomap.c | ||
| xfs_iomap.h | ||
| xfs_iops.c | ||
| xfs_iops.h | ||
| xfs_itable.c | ||
| xfs_itable.h | ||
| xfs_iwalk.c | ||
| xfs_iwalk.h | ||
| xfs_linux.h | ||
| xfs_log_cil.c | ||
| xfs_log_priv.h | ||
| xfs_log_recover.c | ||
| xfs_log.c | ||
| xfs_log.h | ||
| xfs_message.c | ||
| xfs_message.h | ||
| xfs_mount.c | ||
| xfs_mount.h | ||
| xfs_mru_cache.c | ||
| xfs_mru_cache.h | ||
| xfs_ondisk.h | ||
| xfs_pnfs.c | ||
| xfs_pnfs.h | ||
| xfs_pwork.c | ||
| xfs_pwork.h | ||
| xfs_qm_bhv.c | ||
| xfs_qm_syscalls.c | ||
| xfs_qm.c | ||
| xfs_qm.h | ||
| xfs_quota.h | ||
| xfs_quotaops.c | ||
| xfs_refcount_item.c | ||
| xfs_refcount_item.h | ||
| xfs_reflink.c | ||
| xfs_reflink.h | ||
| xfs_rmap_item.c | ||
| xfs_rmap_item.h | ||
| xfs_rtalloc.c | ||
| xfs_rtalloc.h | ||
| xfs_stats.c | ||
| xfs_stats.h | ||
| xfs_super.c | ||
| xfs_super.h | ||
| xfs_symlink.c | ||
| xfs_symlink.h | ||
| xfs_sysctl.c | ||
| xfs_sysctl.h | ||
| xfs_sysfs.c | ||
| xfs_sysfs.h | ||
| xfs_trace.c | ||
| xfs_trace.h | ||
| xfs_trans_ail.c | ||
| xfs_trans_buf.c | ||
| xfs_trans_dquot.c | ||
| xfs_trans_priv.h | ||
| xfs_trans.c | ||
| xfs_trans.h | ||
| xfs_xattr.c | ||
| xfs.h | ||