On 3/1/2017 17:09, Chao Yu wrote:
> This patch adds to account free nids for each NAT blocks, and while
> scanning all free nid bitmap, do check count and skip lookuping in
> full NAT block.
>
> Signed-off-by: Chao Yu <yuch...@huawei.com>
> ---
> fs/f2fs/debug.c | 1 +
> fs/f2fs/f2fs.h | 2 ++
> fs/f2fs/node.c | 34 ++++++++++++++++++++++++++++------
> 3 files changed, 31 insertions(+), 6 deletions(-)
>
> diff --git a/fs/f2fs/debug.c b/fs/f2fs/debug.c
> index a77df377e2e8..ee2d0a485fc3 100644
> --- a/fs/f2fs/debug.c
> +++ b/fs/f2fs/debug.c
> @@ -196,6 +196,7 @@ static void update_mem_info(struct f2fs_sb_info *sbi)
> si->base_mem += (NM_I(sbi)->nat_bits_blocks << F2FS_BLKSIZE_BITS);
> si->base_mem += NM_I(sbi)->nat_blocks * NAT_ENTRY_BITMAP_SIZE;
> si->base_mem += NM_I(sbi)->nat_blocks / 8;
> + si->base_mem += NM_I(sbi)->nat_blocks * sizeof(unsigned short);
>
> get_cache:
> si->cache_mem = 0;
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index 7e2924981eeb..c0b33719dfa9 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -557,6 +557,8 @@ struct f2fs_nm_info {
> struct mutex build_lock; /* lock for build free nids */
> 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 */
>
Sorry for my reply so late.
Is the free_nid_lock needed here?
The free_nid_count should be protected as free_nid_bitmap,
but there isn't any lock for free_nid_bitmap.
How about atomic?
The free node ids management seems a little complex now.
thanks,
Kinglong Mee
> /* for checkpoint */
> char *nat_bitmap; /* NAT bitmap pointer */
> diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
> index 94967171dee8..1a759d45b7e4 100644
> --- a/fs/f2fs/node.c
> +++ b/fs/f2fs/node.c
> @@ -1823,7 +1823,8 @@ static void remove_free_nid(struct f2fs_sb_info *sbi,
> nid_t nid)
> kmem_cache_free(free_nid_slab, i);
> }
>
> -void update_free_nid_bitmap(struct f2fs_sb_info *sbi, nid_t nid, bool set)
> +void update_free_nid_bitmap(struct f2fs_sb_info *sbi, nid_t nid,
> + bool set, bool build)
> {
> struct f2fs_nm_info *nm_i = NM_I(sbi);
> unsigned int nat_ofs = NAT_BLOCK_OFFSET(nid);
> @@ -1836,6 +1837,13 @@ void update_free_nid_bitmap(struct f2fs_sb_info *sbi,
> nid_t nid, bool set)
> set_bit_le(nid_ofs, nm_i->free_nid_bitmap[nat_ofs]);
> else
> clear_bit_le(nid_ofs, nm_i->free_nid_bitmap[nat_ofs]);
> +
> + 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]--;
> + spin_unlock(&nm_i->free_nid_lock);
> }
>
> static void scan_nat_page(struct f2fs_sb_info *sbi,
> @@ -1847,6 +1855,9 @@ static void scan_nat_page(struct f2fs_sb_info *sbi,
> unsigned int nat_ofs = NAT_BLOCK_OFFSET(start_nid);
> int i;
>
> + if (test_bit_le(nat_ofs, nm_i->nat_block_bitmap))
> + return;
> +
> set_bit_le(nat_ofs, nm_i->nat_block_bitmap);
>
> i = start_nid % NAT_ENTRY_PER_BLOCK;
> @@ -1861,7 +1872,7 @@ 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);
> + update_free_nid_bitmap(sbi, start_nid, freed, true);
> }
> }
>
> @@ -1877,6 +1888,8 @@ static void scan_free_nid_bits(struct f2fs_sb_info *sbi)
> for (i = 0; i < nm_i->nat_blocks; i++) {
> if (!test_bit_le(i, nm_i->nat_block_bitmap))
> continue;
> + if (!nm_i->free_nid_count[i])
> + continue;
> for (idx = 0; idx < NAT_ENTRY_PER_BLOCK; idx++) {
> nid_t nid;
>
> @@ -2081,7 +2094,7 @@ 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);
> + update_free_nid_bitmap(sbi, *nid, false, false);
>
> spin_unlock(&nm_i->nid_list_lock);
> return true;
> @@ -2137,7 +2150,7 @@ void alloc_nid_failed(struct f2fs_sb_info *sbi, nid_t
> nid)
>
> nm_i->available_nids++;
>
> - update_free_nid_bitmap(sbi, nid, true);
> + update_free_nid_bitmap(sbi, nid, true, false);
>
> spin_unlock(&nm_i->nid_list_lock);
>
> @@ -2467,11 +2480,11 @@ 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);
> + 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);
> + update_free_nid_bitmap(sbi, nid, false, false);
> spin_unlock(&NM_I(sbi)->nid_list_lock);
> }
> }
> @@ -2651,6 +2664,14 @@ int init_free_nid_cache(struct f2fs_sb_info *sbi)
> GFP_KERNEL);
> if (!nm_i->nat_block_bitmap)
> return -ENOMEM;
> +
> + nm_i->free_nid_count = f2fs_kvzalloc(nm_i->nat_blocks *
> + sizeof(unsigned short), GFP_KERNEL);
> + if (!nm_i->free_nid_count)
> + return -ENOMEM;
> +
> + spin_lock_init(&nm_i->free_nid_lock);
> +
> return 0;
> }
>
> @@ -2730,6 +2751,7 @@ void destroy_node_manager(struct f2fs_sb_info *sbi)
>
> kvfree(nm_i->nat_block_bitmap);
> kvfree(nm_i->free_nid_bitmap);
> + kvfree(nm_i->free_nid_count);
>
> kfree(nm_i->nat_bitmap);
> kfree(nm_i->nat_bits);
>
------------------------------------------------------------------------------
Announcing the Oxford Dictionaries API! The API offers world-renowned
dictionary content that is easy and intuitive to access. Sign up for an
account today to start using our lexical data to power your apps and
projects. Get started today and enter our developer competition.
http://sdm.link/oxford
_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
