Re: [f2fs-dev] [PATCH] f2fs: cover update_free_nid_bitmap with free_list_lock

[Jaegeuk Kim <jaegeuk@kernel.org>]

On 03/13, Kinglong Mee wrote:
> On 3/13/2017 20:10, Chao Yu wrote:
> > free_nid_bitmap and free_nid_count in update_free_nid_bitmap should be
> > updated atomically, use free_list_lock cover them to avoid race in
> 
> nid_list_lock?

Think so.
I merged a modified one in dev-test and started to test it.

Thanks,

> 
> Reviewed-by: Kinglong Mee <kinglongmee@gmail.com>
> 
> > concurrent scenario.
> > 
> > Signed-off-by: Chao Yu <yuchao0@huawei.com>
> > ---
> >  fs/f2fs/f2fs.h |  1 -
> >  fs/f2fs/node.c | 27 +++++++++++----------------
> >  2 files changed, 11 insertions(+), 17 deletions(-)
> > 
> > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> > index 843ce39502bc..d905e53ba524 100644
> > --- a/fs/f2fs/f2fs.h
> > +++ b/fs/f2fs/f2fs.h
> > @@ -561,7 +561,6 @@ struct f2fs_nm_info {
> >  	unsigned char (*free_nid_bitmap)[NAT_ENTRY_BITMAP_SIZE];
> >  	unsigned char *nat_block_bitmap;
> >  	unsigned short *free_nid_count;	/* free nid count of NAT block */
> > -	spinlock_t free_nid_lock;	/* protect updating of nid count */
> >  
> >  	/* for checkpoint */
> >  	char *nat_bitmap;		/* NAT bitmap pointer */
> > diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
> > index 11df8ab32478..3bfffd744f87 100644
> > --- a/fs/f2fs/node.c
> > +++ b/fs/f2fs/node.c
> > @@ -1815,7 +1815,7 @@ static void remove_free_nid(struct f2fs_sb_info *sbi, nid_t nid)
> >  }
> >  
> >  static void update_free_nid_bitmap(struct f2fs_sb_info *sbi, nid_t nid,
> > -			bool set, bool build, bool locked)
> > +							bool set, bool build)
> >  {
> >  	struct f2fs_nm_info *nm_i = NM_I(sbi);
> >  	unsigned int nat_ofs = NAT_BLOCK_OFFSET(nid);
> > @@ -1829,14 +1829,10 @@ static void update_free_nid_bitmap(struct f2fs_sb_info *sbi, nid_t nid,
> >  	else
> >  		__clear_bit_le(nid_ofs, nm_i->free_nid_bitmap[nat_ofs]);
> >  
> > -	if (!locked)
> > -		spin_lock(&nm_i->free_nid_lock);
> >  	if (set)
> >  		nm_i->free_nid_count[nat_ofs]++;
> >  	else if (!build)
> >  		nm_i->free_nid_count[nat_ofs]--;
> > -	if (!locked)
> > -		spin_unlock(&nm_i->free_nid_lock);
> >  }
> >  
> >  static void scan_nat_page(struct f2fs_sb_info *sbi,
> > @@ -1865,7 +1861,9 @@ static void scan_nat_page(struct f2fs_sb_info *sbi,
> >  		f2fs_bug_on(sbi, blk_addr == NEW_ADDR);
> >  		if (blk_addr == NULL_ADDR)
> >  			freed = add_free_nid(sbi, start_nid, true);
> > -		update_free_nid_bitmap(sbi, start_nid, freed, true, false);
> > +		spin_lock(&NM_I(sbi)->nid_list_lock);
> > +		update_free_nid_bitmap(sbi, start_nid, freed, true);
> > +		spin_unlock(&NM_I(sbi)->nid_list_lock);
> >  	}
> >  }
> >  
> > @@ -2020,7 +2018,7 @@ bool alloc_nid(struct f2fs_sb_info *sbi, nid_t *nid)
> >  		__insert_nid_to_list(sbi, i, ALLOC_NID_LIST, false);
> >  		nm_i->available_nids--;
> >  
> > -		update_free_nid_bitmap(sbi, *nid, false, false, false);
> > +		update_free_nid_bitmap(sbi, *nid, false, false);
> >  
> >  		spin_unlock(&nm_i->nid_list_lock);
> >  		return true;
> > @@ -2076,7 +2074,7 @@ void alloc_nid_failed(struct f2fs_sb_info *sbi, nid_t nid)
> >  
> >  	nm_i->available_nids++;
> >  
> > -	update_free_nid_bitmap(sbi, nid, true, false, false);
> > +	update_free_nid_bitmap(sbi, nid, true, false);
> >  
> >  	spin_unlock(&nm_i->nid_list_lock);
> >  
> > @@ -2406,11 +2404,11 @@ static void __flush_nat_entry_set(struct f2fs_sb_info *sbi,
> >  			add_free_nid(sbi, nid, false);
> >  			spin_lock(&NM_I(sbi)->nid_list_lock);
> >  			NM_I(sbi)->available_nids++;
> > -			update_free_nid_bitmap(sbi, nid, true, false, false);
> > +			update_free_nid_bitmap(sbi, nid, true, false);
> >  			spin_unlock(&NM_I(sbi)->nid_list_lock);
> >  		} else {
> >  			spin_lock(&NM_I(sbi)->nid_list_lock);
> > -			update_free_nid_bitmap(sbi, nid, false, false, false);
> > +			update_free_nid_bitmap(sbi, nid, false, false);
> >  			spin_unlock(&NM_I(sbi)->nid_list_lock);
> >  		}
> >  	}
> > @@ -2535,10 +2533,10 @@ inline void load_free_nid_bitmap(struct f2fs_sb_info *sbi)
> >  		nid = i * NAT_ENTRY_PER_BLOCK;
> >  		last_nid = (i + 1) * NAT_ENTRY_PER_BLOCK;
> >  
> > -		spin_lock(&nm_i->free_nid_lock);
> > +		spin_lock(&NM_I(sbi)->nid_list_lock);
> >  		for (; nid < last_nid; nid++)
> > -			update_free_nid_bitmap(sbi, nid, true, true, true);
> > -		spin_unlock(&nm_i->free_nid_lock);
> > +			update_free_nid_bitmap(sbi, nid, true, true);
> > +		spin_unlock(&NM_I(sbi)->nid_list_lock);
> >  	}
> >  
> >  	for (i = 0; i < nm_i->nat_blocks; i++) {
> > @@ -2629,9 +2627,6 @@ static int init_free_nid_cache(struct f2fs_sb_info *sbi)
> >  					sizeof(unsigned short), GFP_KERNEL);
> >  	if (!nm_i->free_nid_count)
> >  		return -ENOMEM;
> > -
> > -	spin_lock_init(&nm_i->free_nid_lock);
> > -
> >  	return 0;
> >  }
> >  
> >