when performing buffered writes in a large section, overhead is incurred due to the iteration through ckpt_valid_blocks within the section. when SEGS_PER_SEC is 128, this overhead accounts for 20% within the f2fs_write_single_data_page routine. as the size of the section increases, the overhead also grows. to handle this problem ckpt_valid_blocks is added within the section entries.
Test insmod null_blk.ko nr_devices=1 completion_nsec=1 submit_queues=8 hw_queue_depth=64 max_sectors=512 bs=4096 memory_backed=1 make_f2fs /dev/block/nullb0 make_f2fs -s 128 /dev/block/nullb0 fio --bs=512k --size=1536M --rw=write --name=1 --filename=/mnt/test_dir/seq_write --ioengine=io_uring --iodepth=64 --end_fsync=1 before SEGS_PER_SEC 1 2556MiB/s SEGS_PER_SEC 128 2145MiB/s after SEGS_PER_SEC 1 2556MiB/s SEGS_PER_SEC 128 2556MiB/s Signed-off-by: yohan.joung <yohan.jo...@sk.com> --- fs/f2fs/segment.c | 41 +++++++++++++++++++++++++++++------- fs/f2fs/segment.h | 53 +++++++++++++++++++++++++++++++++++++---------- 2 files changed, 76 insertions(+), 18 deletions(-) diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index 671bc5a8fd4a..7a53f2d8a474 100644 --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -2447,7 +2447,7 @@ static void update_segment_mtime(struct f2fs_sb_info *sbi, block_t blkaddr, * that the consecutive input blocks belong to the same segment. */ static int update_sit_entry_for_release(struct f2fs_sb_info *sbi, struct seg_entry *se, - block_t blkaddr, unsigned int offset, int del) + unsigned int segno, block_t blkaddr, unsigned int offset, int del) { bool exist; #ifdef CONFIG_F2FS_CHECK_FS @@ -2492,15 +2492,22 @@ static int update_sit_entry_for_release(struct f2fs_sb_info *sbi, struct seg_ent f2fs_test_and_clear_bit(offset + i, se->discard_map)) sbi->discard_blks++; - if (!f2fs_test_bit(offset + i, se->ckpt_valid_map)) +#ifdef CONFIG_F2FS_CHECK_FS + if (__is_large_section(sbi)) + sanity_check_valid_blocks(sbi, segno); +#endif + if (!f2fs_test_bit(offset + i, se->ckpt_valid_map)) { se->ckpt_valid_blocks -= 1; + if (__is_large_section(sbi)) + get_sec_entry(sbi, segno)->ckpt_valid_blocks -= 1; + } } return del; } static int update_sit_entry_for_alloc(struct f2fs_sb_info *sbi, struct seg_entry *se, - block_t blkaddr, unsigned int offset, int del) + unsigned int segno, block_t blkaddr, unsigned int offset, int del) { bool exist; #ifdef CONFIG_F2FS_CHECK_FS @@ -2532,13 +2539,23 @@ static int update_sit_entry_for_alloc(struct f2fs_sb_info *sbi, struct seg_entry * SSR should never reuse block which is checkpointed * or newly invalidated. */ +#ifdef CONFIG_F2FS_CHECK_FS + if (__is_large_section(sbi)) + sanity_check_valid_blocks(sbi, segno); +#endif if (!is_sbi_flag_set(sbi, SBI_CP_DISABLED)) { - if (!f2fs_test_and_set_bit(offset, se->ckpt_valid_map)) + if (!f2fs_test_and_set_bit(offset, se->ckpt_valid_map)) { se->ckpt_valid_blocks++; + if (__is_large_section(sbi)) + get_sec_entry(sbi, segno)->ckpt_valid_blocks++; + } } - if (!f2fs_test_bit(offset, se->ckpt_valid_map)) + if (!f2fs_test_bit(offset, se->ckpt_valid_map)) { se->ckpt_valid_blocks += del; + if (__is_large_section(sbi)) + get_sec_entry(sbi, segno)->ckpt_valid_blocks += del; + } return del; } @@ -2569,9 +2586,9 @@ static void update_sit_entry(struct f2fs_sb_info *sbi, block_t blkaddr, int del) /* Update valid block bitmap */ if (del > 0) { - del = update_sit_entry_for_alloc(sbi, se, blkaddr, offset, del); + del = update_sit_entry_for_alloc(sbi, se, segno, blkaddr, offset, del); } else { - del = update_sit_entry_for_release(sbi, se, blkaddr, offset, del); + del = update_sit_entry_for_release(sbi, se, segno, blkaddr, offset, del); } __mark_sit_entry_dirty(sbi, segno); @@ -4700,12 +4717,16 @@ void f2fs_flush_sit_entries(struct f2fs_sb_info *sbi, struct cp_control *cpc) &sit_in_journal(journal, offset)); check_block_count(sbi, segno, &sit_in_journal(journal, offset)); + if (__is_large_section(sbi)) + set_ckpt_valid_blocks(sbi, segno); } else { sit_offset = SIT_ENTRY_OFFSET(sit_i, segno); seg_info_to_raw_sit(se, &raw_sit->entries[sit_offset]); check_block_count(sbi, segno, &raw_sit->entries[sit_offset]); + if (__is_large_section(sbi)) + set_ckpt_valid_blocks(sbi, segno); } __clear_bit(segno, bitmap); @@ -5029,6 +5050,12 @@ static int build_sit_entries(struct f2fs_sb_info *sbi) } up_read(&curseg->journal_rwsem); + /* update ckpt_ckpt_valid_block */ + if (__is_large_section(sbi)) { + for (unsigned int segno = 0; segno < MAIN_SEGS(sbi); segno += SEGS_PER_SEC(sbi)) + set_ckpt_valid_blocks(sbi, segno); + } + if (err) return err; diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h index 5777b385e7d2..ebc90d3cb57c 100644 --- a/fs/f2fs/segment.h +++ b/fs/f2fs/segment.h @@ -211,6 +211,7 @@ struct seg_entry { struct sec_entry { unsigned int valid_blocks; /* # of valid blocks in a section */ + unsigned int ckpt_valid_blocks; /* # of valid blocks last cp in a section */ }; #define MAX_SKIP_GC_COUNT 16 @@ -347,22 +348,52 @@ static inline unsigned int get_valid_blocks(struct f2fs_sb_info *sbi, static inline unsigned int get_ckpt_valid_blocks(struct f2fs_sb_info *sbi, unsigned int segno, bool use_section) { - if (use_section && __is_large_section(sbi)) { - unsigned int secno = GET_SEC_FROM_SEG(sbi, segno); - unsigned int start_segno = GET_SEG_FROM_SEC(sbi, secno); - unsigned int blocks = 0; - int i; + if (use_section && __is_large_section(sbi)) + return get_sec_entry(sbi, segno)->ckpt_valid_blocks; + else + return get_seg_entry(sbi, segno)->ckpt_valid_blocks; +} + +static inline void set_ckpt_valid_blocks(struct f2fs_sb_info *sbi, + unsigned int segno) +{ + unsigned int secno = GET_SEC_FROM_SEG(sbi, segno); + unsigned int start_segno = GET_SEG_FROM_SEC(sbi, secno); + unsigned int blocks = 0; + int i; - for (i = 0; i < SEGS_PER_SEC(sbi); i++, start_segno++) { - struct seg_entry *se = get_seg_entry(sbi, start_segno); + for (i = 0; i < SEGS_PER_SEC(sbi); i++, start_segno++) { + struct seg_entry *se = get_seg_entry(sbi, start_segno); - blocks += se->ckpt_valid_blocks; - } - return blocks; + blocks += se->ckpt_valid_blocks; } - return get_seg_entry(sbi, segno)->ckpt_valid_blocks; + get_sec_entry(sbi, segno)->ckpt_valid_blocks = blocks; } +#ifdef CONFIG_F2FS_CHECK_FS +static inline void sanity_check_valid_blocks(struct f2fs_sb_info *sbi, + unsigned int segno) +{ + unsigned int secno = GET_SEC_FROM_SEG(sbi, segno); + unsigned int start_segno = GET_SEG_FROM_SEC(sbi, secno); + unsigned int blocks = 0; + int i; + + for (i = 0; i < SEGS_PER_SEC(sbi); i++, start_segno++) { + struct seg_entry *se = get_seg_entry(sbi, start_segno); + + blocks += se->ckpt_valid_blocks; + } + + if (blocks != get_sec_entry(sbi, segno)->ckpt_valid_blocks) { + f2fs_err(sbi, + "Inconsistent ckpt valid blocks: " + "seg entry(%d) vs sec entry(%d) at secno %d", + blocks, get_sec_entry(sbi, segno)->ckpt_valid_blocks, secno); + f2fs_bug_on(sbi, 1); + } +} +#endif static inline void seg_info_from_raw_sit(struct seg_entry *se, struct f2fs_sit_entry *rs) { -- 2.33.0 _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel