Re: [PATCH] f2fs: do not use discard_map for non-discard case
From: Chao Yu
Date: Fri Aug 05 2016 - 05:40:10 EST
Hi Jaegeuk,
On 2016/8/5 3:04, Jaegeuk Kim wrote:
> We don't need to keep discard_map, if f2fs has no discard mount option.
In trim_fs path, we will still use discard_map though, right?
Thanks,
>
> Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
> ---
> fs/f2fs/f2fs.h | 2 ++
> fs/f2fs/segment.c | 87 ++++++++++++++++++++++++++++++++++++++++++++++---------
> fs/f2fs/super.c | 10 +++++++
> 3 files changed, 86 insertions(+), 13 deletions(-)
>
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index 61cb83d..a400715 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -2036,6 +2036,8 @@ int lookup_journal_in_cursum(struct f2fs_journal *, int, unsigned int, int);
> void flush_sit_entries(struct f2fs_sb_info *, struct cp_control *);
> int build_segment_manager(struct f2fs_sb_info *);
> void destroy_segment_manager(struct f2fs_sb_info *);
> +int build_discard_map(struct f2fs_sb_info *);
> +void destroy_discard_map(struct f2fs_sb_info *);
> int __init create_segment_manager_caches(void);
> void destroy_segment_manager_caches(void);
>
> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
> index a46296f..66822d3 100644
> --- a/fs/f2fs/segment.c
> +++ b/fs/f2fs/segment.c
> @@ -660,11 +660,11 @@ static void add_discard_addrs(struct f2fs_sb_info *sbi, struct cp_control *cpc)
> bool force = (cpc->reason == CP_DISCARD);
> int i;
>
> - if (se->valid_blocks == max_blocks)
> + if (se->valid_blocks == max_blocks || !test_opt(sbi, DISCARD))
> return;
>
> if (!force) {
> - if (!test_opt(sbi, DISCARD) || !se->valid_blocks ||
> + if (!se->valid_blocks ||
> SM_I(sbi)->nr_discards >= SM_I(sbi)->max_discards)
> return;
> }
> @@ -818,12 +818,14 @@ static void update_sit_entry(struct f2fs_sb_info *sbi, block_t blkaddr, int del)
> if (del > 0) {
> if (f2fs_test_and_set_bit(offset, se->cur_valid_map))
> f2fs_bug_on(sbi, 1);
> - if (!f2fs_test_and_set_bit(offset, se->discard_map))
> + if (test_opt(sbi, DISCARD) &&
> + !f2fs_test_and_set_bit(offset, se->discard_map))
> sbi->discard_blks--;
> } else {
> if (!f2fs_test_and_clear_bit(offset, se->cur_valid_map))
> f2fs_bug_on(sbi, 1);
> - if (f2fs_test_and_clear_bit(offset, se->discard_map))
> + if (test_opt(sbi, DISCARD) &&
> + f2fs_test_and_clear_bit(offset, se->discard_map))
> sbi->discard_blks++;
> }
> if (!f2fs_test_bit(offset, se->ckpt_valid_map))
> @@ -2096,6 +2098,55 @@ out:
> set_prefree_as_free_segments(sbi);
> }
>
> +static int __init_discard_map(struct f2fs_sb_info *sbi)
> +{
> + struct sit_info *sit_i;
> + unsigned int start;
> +
> + if (!test_opt(sbi, DISCARD))
> + return 0;
> +
> + sit_i = SIT_I(sbi);
> +
> + for (start = 0; start < MAIN_SEGS(sbi); start++) {
> + sit_i->sentries[start].discard_map
> + = kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
> + if (!sit_i->sentries[start].discard_map)
> + return -ENOMEM;
> + }
> + return 0;
> +}
> +
> +static void __build_discard_map(struct f2fs_sb_info *sbi)
> +{
> + struct sit_info *sit_i;
> + unsigned int start;
> +
> + if (!test_opt(sbi, DISCARD))
> + return;
> +
> + sit_i = SIT_I(sbi);
> +
> + for (start = 0; start < MAIN_SEGS(sbi); start++) {
> + struct seg_entry *se = &sit_i->sentries[start];
> +
> + memcpy(se->discard_map, se->cur_valid_map, SIT_VBLOCK_MAP_SIZE);
> + sbi->discard_blks += sbi->blocks_per_seg - se->valid_blocks;
> + }
> +}
> +
> +int build_discard_map(struct f2fs_sb_info *sbi)
> +{
> + int err;
> +
> + err = __init_discard_map(sbi);
> + if (err)
> + return err;
> +
> + __build_discard_map(sbi);
> + return 0;
> +}
> +
> static int build_sit_info(struct f2fs_sb_info *sbi)
> {
> struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
> @@ -2127,14 +2178,14 @@ static int build_sit_info(struct f2fs_sb_info *sbi)
> = kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
> sit_i->sentries[start].ckpt_valid_map
> = kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
> - sit_i->sentries[start].discard_map
> - = kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
> if (!sit_i->sentries[start].cur_valid_map ||
> - !sit_i->sentries[start].ckpt_valid_map ||
> - !sit_i->sentries[start].discard_map)
> + !sit_i->sentries[start].ckpt_valid_map)
> return -ENOMEM;
> }
>
> + if (__init_discard_map(sbi))
> + return -ENOMEM;
> +
> sit_i->tmp_map = kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
> if (!sit_i->tmp_map)
> return -ENOMEM;
> @@ -2275,10 +2326,6 @@ got_it:
> check_block_count(sbi, start, &sit);
> seg_info_from_raw_sit(se, &sit);
>
> - /* build discard map only one time */
> - memcpy(se->discard_map, se->cur_valid_map, SIT_VBLOCK_MAP_SIZE);
> - sbi->discard_blks += sbi->blocks_per_seg - se->valid_blocks;
> -
> if (sbi->segs_per_sec > 1) {
> struct sec_entry *e = get_sec_entry(sbi, start);
> e->valid_blocks += se->valid_blocks;
> @@ -2286,6 +2333,9 @@ got_it:
> }
> start_blk += readed;
> } while (start_blk < sit_blk_cnt);
> +
> + /* build discard map only one time */
> + __build_discard_map(sbi);
> }
>
> static void init_free_segmap(struct f2fs_sb_info *sbi)
> @@ -2522,6 +2572,17 @@ static void destroy_free_segmap(struct f2fs_sb_info *sbi)
> kfree(free_i);
> }
>
> +void destroy_discard_map(struct f2fs_sb_info *sbi)
> +{
> + struct sit_info *sit_i = SIT_I(sbi);
> + unsigned int start;
> +
> + for (start = 0; start < MAIN_SEGS(sbi); start++) {
> + kfree(sit_i->sentries[start].discard_map);
> + sit_i->sentries[start].discard_map = NULL;
> + }
> +}
> +
> static void destroy_sit_info(struct f2fs_sb_info *sbi)
> {
> struct sit_info *sit_i = SIT_I(sbi);
> @@ -2534,8 +2595,8 @@ static void destroy_sit_info(struct f2fs_sb_info *sbi)
> for (start = 0; start < MAIN_SEGS(sbi); start++) {
> kfree(sit_i->sentries[start].cur_valid_map);
> kfree(sit_i->sentries[start].ckpt_valid_map);
> - kfree(sit_i->sentries[start].discard_map);
> }
> + destroy_discard_map(sbi);
> }
> kfree(sit_i->tmp_map);
>
> diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
> index 7f863a6..eec5c95 100644
> --- a/fs/f2fs/super.c
> +++ b/fs/f2fs/super.c
> @@ -1001,6 +1001,7 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data)
> bool need_restart_gc = false;
> bool need_stop_gc = false;
> bool no_extent_cache = !test_opt(sbi, EXTENT_CACHE);
> + bool no_discard = !test_opt(sbi, DISCARD);
>
> /*
> * Save the old mount options in case we
> @@ -1079,6 +1080,15 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data)
> if (err)
> goto restore_gc;
> }
> +
> + /* initialize discard map structure */
> + if (no_discard && test_opt(sbi, DISCARD)) {
> + err = build_discard_map(sbi);
> + if (err)
> + goto restore_gc;
> + } else if (!no_discard && !test_opt(sbi, DISCARD)) {
> + destroy_discard_map(sbi);
> + }
> skip:
> /* Update the POSIXACL Flag */
> sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
>