On 03/02, Chao Yu wrote: > On 2022/3/1 12:48, Jaegeuk Kim wrote: > > 1. waiting for f2fs_evict_inode > > [ 5560.043945] __wait_on_freeing_inode+0xac/0xf0 > > [ 5560.045540] ? var_wake_function+0x30/0x30 > > [ 5560.047036] find_inode_fast+0x6d/0xc0 > > [ 5560.048473] iget_locked+0x79/0x230 > > [ 5560.049933] f2fs_iget+0x27/0x1200 [f2fs] > > [ 5560.051496] f2fs_lookup+0x18c/0x3e0 [f2fs] > > [ 5560.053069] __lookup_slow+0x84/0x150 > > [ 5560.054503] walk_component+0x141/0x1b0 > > [ 5560.055938] link_path_walk.part.0+0x23b/0x360 > > [ 5560.057541] ? end_bio_bh_io_sync+0x37/0x50 > > [ 5560.059086] path_parentat+0x3c/0x90 > > [ 5560.060492] filename_parentat+0xd7/0x1e0 > > [ 5560.062002] ? blk_mq_free_request+0x127/0x150 > > [ 5560.063576] do_renameat2+0xc1/0x5b0 > > --> sb_start_write(m->mnt_sb); -> __sb_start_write(sb, SB_FREEZE_WRITE); > > > > [ 5560.064999] ? __check_object_size+0x13f/0x150 > > [ 5560.066559] ? strncpy_from_user+0x44/0x150 > > [ 5560.068038] ? getname_flags.part.0+0x4c/0x1b0 > > [ 5560.069617] __x64_sys_renameat2+0x51/0x60 > > > > 2. waiting for sb_start_intwrite -> __sb_start_write(sb, SB_FREEZE_FS); > > It's still not clear that why __sb_start_write(sb, SB_FREEZE_FS) will be > blocked, > as SB_FREEZE_FS and SB_FREEZE_WRITE points to different locks.
It seems I missed another call, thaw_super(), got SB_FREEZE_FS and then being stuck to grab SB_FREEZE_WRITE. > > Thread A Thread B > Thread C > - rename > - sb_start_write > - __sb_start_write(SB_FREEZE_WRITE) > ... > - f2fs_lookup > ... > - __wait_on_freeing_inode > - drop_slab > - prune_icache_sb > - inode_lru_isolate > :inode->i_state |= I_FREEING > > - Is there any flow that it has already held > > SB_FREEZE_FS and try to lock SB_FREEZE_WRITE? > - f2fs_evict_inode > - __sb_start_write(SB_FREEZE_FS) > > Thanks, > > > > > [ 5560.152447] percpu_rwsem_wait+0xaf/0x160 > > [ 5560.154000] ? percpu_down_write+0xd0/0xd0 > > [ 5560.155498] __percpu_down_read+0x4e/0x60 > > [ 5560.157000] f2fs_evict_inode+0x5a3/0x610 [f2fs] > > [ 5560.158648] ? var_wake_function+0x30/0x30 > > [ 5560.160341] evict+0xd2/0x180 > > [ 5560.161728] prune_icache_sb+0x81/0xb0 > > --> inode_lru_isolate() -> inode->i_state |= I_FREEING; > > > > [ 5560.163179] super_cache_scan+0x169/0x1f0 > > [ 5560.164675] do_shrink_slab+0x145/0x2b0 > > [ 5560.166121] shrink_slab+0x186/0x2d0 > > [ 5560.167481] drop_slab_node+0x4a/0x90 > > [ 5560.168876] drop_slab+0x3e/0x80 > > [ 5560.170178] drop_caches_sysctl_handler+0x75/0x90 > > [ 5560.171761] proc_sys_call_handler+0x149/0x280 > > [ 5560.173328] proc_sys_write+0x13/0x20 > > [ 5560.174667] new_sync_write+0x117/0x1b0 > > [ 5560.176120] vfs_write+0x1d5/0x270 > > [ 5560.177409] ksys_write+0x67/0xe0 > > > > Signed-off-by: Jaegeuk Kim <[email protected]> > > --- > > Note, I found this call stack. > > > > fs/f2fs/inode.c | 2 -- > > 1 file changed, 2 deletions(-) > > > > diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c > > index ab8e0c06c78c..882db4bd917b 100644 > > --- a/fs/f2fs/inode.c > > +++ b/fs/f2fs/inode.c > > @@ -778,7 +778,6 @@ void f2fs_evict_inode(struct inode *inode) > > f2fs_remove_ino_entry(sbi, inode->i_ino, UPDATE_INO); > > f2fs_remove_ino_entry(sbi, inode->i_ino, FLUSH_INO); > > - sb_start_intwrite(inode->i_sb); > > set_inode_flag(inode, FI_NO_ALLOC); > > i_size_write(inode, 0); > > retry: > > @@ -809,7 +808,6 @@ void f2fs_evict_inode(struct inode *inode) > > if (dquot_initialize_needed(inode)) > > set_sbi_flag(sbi, SBI_QUOTA_NEED_REPAIR); > > } > > - sb_end_intwrite(inode->i_sb); > > no_delete: > > dquot_drop(inode); _______________________________________________ Linux-f2fs-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
