Re: [f2fs-dev] [PATCH 2/4] f2fs: build stat_info before orphan inode recovery

[Jaegeuk Kim <jaegeuk@kernel.org>]

On 03/09, Chao Yu wrote:
> On 2017/3/8 6:13, Jaegeuk Kim wrote:
> > f2fs_sync_fs() -> write_checkpoint() calls stat_inc_cp_count(sbi->stat_info),
> > which needs stat_info allocation.
> > Otherwise, we can hit:
> > 
> > [254042.598623]  ? count_shadow_nodes+0xa0/0xa0
> > [254042.598633]  f2fs_sync_fs+0x65/0xd0 [f2fs]
> > [254042.598645]  f2fs_balance_fs_bg+0xe4/0x1c0 [f2fs]
> > [254042.598657]  f2fs_write_node_pages+0x34/0x1a0 [f2fs]
> > [254042.598664]  ? pagevec_lookup_entries+0x1e/0x30
> > [254042.598673]  do_writepages+0x1e/0x30
> > [254042.598682]  __writeback_single_inode+0x45/0x330
> > [254042.598688]  writeback_single_inode+0xd7/0x190
> > [254042.598694]  write_inode_now+0x86/0xa0
> > [254042.598699]  iput+0x122/0x200
> > [254042.598709]  f2fs_fill_super+0xd4a/0x14d0 [f2fs]
> > [254042.598717]  mount_bdev+0x184/0x1c0
> > [254042.598934]  ? f2fs_commit_super+0x100/0x100 [f2fs]
> > [254042.599142]  f2fs_mount+0x15/0x20 [f2fs]
> > [254042.599349]  mount_fs+0x39/0x160
> > [254042.599554]  ? __alloc_percpu+0x15/0x20
> > [254042.599759]  vfs_kern_mount+0x67/0x110
> > [254042.599972]  do_mount+0x1bb/0xc80
> > [254042.600175]  ? memdup_user+0x42/0x60
> > [254042.600380]  SyS_mount+0x83/0xd0
> > [254042.600583]  entry_SYSCALL_64_fastpath+0x1e/0xad
> > 
> > Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
> > ---
> >  fs/f2fs/super.c | 10 +++++-----
> >  1 file changed, 5 insertions(+), 5 deletions(-)
> > 
> > diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
> > index 96fe8ed73100..cfb40d3fd875 100644
> > --- a/fs/f2fs/super.c
> > +++ b/fs/f2fs/super.c
> > @@ -2022,6 +2022,10 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
> >  
> >  	f2fs_join_shrinker(sbi);
> >  
> > +	err = f2fs_build_stats(sbi);
> > +	if (err)
> > +		goto free_nm;
> 
> Both node_inode and shrinker need to be released and detached.
> 
> How about relocate f2fs_build_stats in front of build_segment_manager?

I just got another panic to try this, since sys/../f2fs/status needs them.

Thanks,

> 
> Thanks,
> 
> > +
> >  	/* if there are nt orphan nodes free them */
> >  	err = recover_orphan_inodes(sbi);
> >  	if (err)
> > @@ -2046,10 +2050,6 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
> >  		goto free_root_inode;
> >  	}
> >  
> > -	err = f2fs_build_stats(sbi);
> > -	if (err)
> > -		goto free_root_inode;
> > -
> >  	if (f2fs_proc_root)
> >  		sbi->s_proc = proc_mkdir(sb->s_id, f2fs_proc_root);
> >  
> > @@ -2143,7 +2143,6 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
> >  		remove_proc_entry("segment_bits", sbi->s_proc);
> >  		remove_proc_entry(sb->s_id, f2fs_proc_root);
> >  	}
> > -	f2fs_destroy_stats(sbi);
> >  free_root_inode:
> >  	dput(sb->s_root);
> >  	sb->s_root = NULL;
> > @@ -2161,6 +2160,7 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
> >  	truncate_inode_pages_final(META_MAPPING(sbi));
> >  	iput(sbi->node_inode);
> >  	mutex_unlock(&sbi->umount_mutex);
> > +	f2fs_destroy_stats(sbi);
> >  free_nm:
> >  	destroy_node_manager(sbi);
> >  free_sm:
> >