* [PATCH v3 1/2] f2fs: add a method for calculating the remaining blocks in the current segment in LFS mode.
@ 2025-05-07 4:30 yohan.joung
2025-05-07 4:30 ` [PATCH v3 2/2] f2fs: add ckpt_valid_blocks to the section entry yohan.joung
2025-05-07 8:25 ` [PATCH v3 1/2] f2fs: add a method for calculating the remaining blocks in the current segment in LFS mode Chao Yu
0 siblings, 2 replies; 5+ messages in thread
From: yohan.joung @ 2025-05-07 4:30 UTC (permalink / raw)
To: jaegeuk, chao, daehojeong
Cc: linux-kernel, linux-f2fs-devel, pilhyun.kim, yohan.joung
In LFS mode, the previous segment cannot use invalid blocks,
so the remaining blocks from the next_blkoff of the current segment
to the end of the section are calculated.
Signed-off-by: yohan.joung <yohan.joung@sk.com>
---
fs/f2fs/segment.h | 23 +++++++++++++++++++----
1 file changed, 19 insertions(+), 4 deletions(-)
diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
index 03c0f59be5a8..f5d30f32ebdb 100644
--- a/fs/f2fs/segment.h
+++ b/fs/f2fs/segment.h
@@ -102,6 +102,8 @@ static inline void sanity_check_seg_type(struct f2fs_sb_info *sbi,
#define CAP_SEGS_PER_SEC(sbi) \
(SEGS_PER_SEC(sbi) - \
BLKS_TO_SEGS(sbi, (sbi)->unusable_blocks_per_sec))
+#define GET_START_SEG_FROM_SEC(sbi, segno) \
+ (rounddown(segno, SEGS_PER_SEC(sbi)))
#define GET_SEC_FROM_SEG(sbi, segno) \
(((segno) == -1) ? -1 : (segno) / SEGS_PER_SEC(sbi))
#define GET_SEG_FROM_SEC(sbi, secno) \
@@ -582,8 +584,14 @@ static inline bool has_curseg_enough_space(struct f2fs_sb_info *sbi,
if (unlikely(segno == NULL_SEGNO))
return false;
- left_blocks = CAP_BLKS_PER_SEC(sbi) -
- get_ckpt_valid_blocks(sbi, segno, true);
+ if (f2fs_lfs_mode(sbi) && __is_large_section(sbi)) {
+ left_blocks = CAP_BLKS_PER_SEC(sbi) -
+ (segno - GET_START_SEG_FROM_SEC(sbi, segno)) * BLKS_PER_SEG(sbi) -
+ CURSEG_I(sbi, i)->next_blkoff;
+ } else {
+ left_blocks = CAP_BLKS_PER_SEC(sbi) -
+ get_ckpt_valid_blocks(sbi, segno, true);
+ }
blocks = i <= CURSEG_COLD_DATA ? data_blocks : node_blocks;
if (blocks > left_blocks)
@@ -596,8 +604,15 @@ static inline bool has_curseg_enough_space(struct f2fs_sb_info *sbi,
if (unlikely(segno == NULL_SEGNO))
return false;
- left_blocks = CAP_BLKS_PER_SEC(sbi) -
- get_ckpt_valid_blocks(sbi, segno, true);
+ if (f2fs_lfs_mode(sbi) && __is_large_section(sbi)) {
+ left_blocks = CAP_BLKS_PER_SEC(sbi) -
+ (segno - GET_START_SEG_FROM_SEC(sbi, segno)) * BLKS_PER_SEG(sbi) -
+ CURSEG_I(sbi, CURSEG_HOT_DATA)->next_blkoff;
+ } else {
+ left_blocks = CAP_BLKS_PER_SEC(sbi) -
+ get_ckpt_valid_blocks(sbi, segno, true);
+ }
+
if (dent_blocks > left_blocks)
return false;
return true;
--
2.33.0
^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH v3 2/2] f2fs: add ckpt_valid_blocks to the section entry
2025-05-07 4:30 [PATCH v3 1/2] f2fs: add a method for calculating the remaining blocks in the current segment in LFS mode yohan.joung
@ 2025-05-07 4:30 ` yohan.joung
2025-05-07 8:47 ` Chao Yu
2025-05-07 8:25 ` [PATCH v3 1/2] f2fs: add a method for calculating the remaining blocks in the current segment in LFS mode Chao Yu
1 sibling, 1 reply; 5+ messages in thread
From: yohan.joung @ 2025-05-07 4:30 UTC (permalink / raw)
To: jaegeuk, chao, daehojeong
Cc: linux-kernel, linux-f2fs-devel, pilhyun.kim, yohan.joung
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.joung@sk.com>
---
fs/f2fs/segment.c | 29 ++++++++++++++++++++++-------
fs/f2fs/segment.h | 29 ++++++++++++++++++-----------
2 files changed, 40 insertions(+), 18 deletions(-)
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 671bc5a8fd4a..09b66a755559 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 +2492,18 @@ 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))
+ 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
@@ -2533,12 +2536,18 @@ static int update_sit_entry_for_alloc(struct f2fs_sb_info *sbi, struct seg_entry
* or newly invalidated.
*/
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 +2578,9 @@ 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);
@@ -5029,6 +5038,12 @@ 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 f5d30f32ebdb..e91d944f003a 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
@@ -347,20 +348,26 @@ 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;
}
static inline void seg_info_from_raw_sit(struct seg_entry *se,
--
2.33.0
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v3 1/2] f2fs: add a method for calculating the remaining blocks in the current segment in LFS mode.
2025-05-07 4:30 [PATCH v3 1/2] f2fs: add a method for calculating the remaining blocks in the current segment in LFS mode yohan.joung
2025-05-07 4:30 ` [PATCH v3 2/2] f2fs: add ckpt_valid_blocks to the section entry yohan.joung
@ 2025-05-07 8:25 ` Chao Yu
1 sibling, 0 replies; 5+ messages in thread
From: Chao Yu @ 2025-05-07 8:25 UTC (permalink / raw)
To: yohan.joung, jaegeuk, daehojeong
Cc: chao, linux-kernel, linux-f2fs-devel, pilhyun.kim
On 5/7/25 12:30, yohan.joung wrote:
> In LFS mode, the previous segment cannot use invalid blocks,
> so the remaining blocks from the next_blkoff of the current segment
> to the end of the section are calculated.
>
> Signed-off-by: yohan.joung <yohan.joung@sk.com>
> ---
> fs/f2fs/segment.h | 23 +++++++++++++++++++----
> 1 file changed, 19 insertions(+), 4 deletions(-)
>
> diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
> index 03c0f59be5a8..f5d30f32ebdb 100644
> --- a/fs/f2fs/segment.h
> +++ b/fs/f2fs/segment.h
> @@ -102,6 +102,8 @@ static inline void sanity_check_seg_type(struct f2fs_sb_info *sbi,
> #define CAP_SEGS_PER_SEC(sbi) \
> (SEGS_PER_SEC(sbi) - \
> BLKS_TO_SEGS(sbi, (sbi)->unusable_blocks_per_sec))
> +#define GET_START_SEG_FROM_SEC(sbi, segno) \
> + (rounddown(segno, SEGS_PER_SEC(sbi)))
> #define GET_SEC_FROM_SEG(sbi, segno) \
> (((segno) == -1) ? -1 : (segno) / SEGS_PER_SEC(sbi))
> #define GET_SEG_FROM_SEC(sbi, secno) \
> @@ -582,8 +584,14 @@ static inline bool has_curseg_enough_space(struct f2fs_sb_info *sbi,
> if (unlikely(segno == NULL_SEGNO))
> return false;
>
> - left_blocks = CAP_BLKS_PER_SEC(sbi) -
> - get_ckpt_valid_blocks(sbi, segno, true);
> + if (f2fs_lfs_mode(sbi) && __is_large_section(sbi)) {
> + left_blocks = CAP_BLKS_PER_SEC(sbi) -
> + (segno - GET_START_SEG_FROM_SEC(sbi, segno)) * BLKS_PER_SEG(sbi) -
SEGS_TO_BLKS(sbi, (segno - GET_START_SEG_FROM_SEC(sbi, segno))) ?
> + CURSEG_I(sbi, i)->next_blkoff;
> + } else {
> + left_blocks = CAP_BLKS_PER_SEC(sbi) -
> + get_ckpt_valid_blocks(sbi, segno, true);
> + }
>
> blocks = i <= CURSEG_COLD_DATA ? data_blocks : node_blocks;
> if (blocks > left_blocks)
> @@ -596,8 +604,15 @@ static inline bool has_curseg_enough_space(struct f2fs_sb_info *sbi,
> if (unlikely(segno == NULL_SEGNO))
> return false;
>
> - left_blocks = CAP_BLKS_PER_SEC(sbi) -
> - get_ckpt_valid_blocks(sbi, segno, true);
> + if (f2fs_lfs_mode(sbi) && __is_large_section(sbi)) {
> + left_blocks = CAP_BLKS_PER_SEC(sbi) -
> + (segno - GET_START_SEG_FROM_SEC(sbi, segno)) * BLKS_PER_SEG(sbi) -
Ditto,
> + CURSEG_I(sbi, CURSEG_HOT_DATA)->next_blkoff;
> + } else {
> + left_blocks = CAP_BLKS_PER_SEC(sbi) -
> + get_ckpt_valid_blocks(sbi, segno, true);
> + }
> +
> if (dent_blocks > left_blocks)
> return false;
> return true;
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v3 2/2] f2fs: add ckpt_valid_blocks to the section entry
2025-05-07 4:30 ` [PATCH v3 2/2] f2fs: add ckpt_valid_blocks to the section entry yohan.joung
@ 2025-05-07 8:47 ` Chao Yu
2025-05-07 9:03 ` [f2fs-dev] " yohan.joung
0 siblings, 1 reply; 5+ messages in thread
From: Chao Yu @ 2025-05-07 8:47 UTC (permalink / raw)
To: yohan.joung, jaegeuk, daehojeong
Cc: chao, linux-kernel, linux-f2fs-devel, pilhyun.kim
On 5/7/25 12:30, yohan.joung wrote:
> 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.joung@sk.com>
> ---
> fs/f2fs/segment.c | 29 ++++++++++++++++++++++-------
> fs/f2fs/segment.h | 29 ++++++++++++++++++-----------
> 2 files changed, 40 insertions(+), 18 deletions(-)
>
> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
> index 671bc5a8fd4a..09b66a755559 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 +2492,18 @@ 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))
> + 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
> @@ -2533,12 +2536,18 @@ static int update_sit_entry_for_alloc(struct f2fs_sb_info *sbi, struct seg_entry
> * or newly invalidated.
> */
> 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++;
What about adding sanity_check_valid_blocks() to check consistency between
valid blocks of segments and valid blocks of section? Covered w/
CONFIG_F2FS_CHECK_FS.
> + }
> }
>
> - 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 +2578,9 @@ 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);
> @@ -5029,6 +5038,12 @@ 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))
unsigned int segno;
for (segno = 0; segno < MAIN_SEGS(sbi);
segno += SEGS_PER_SEC(sbi))
> + set_ckpt_valid_blocks(sbi, segno);
ckpt_valid_blocks will be reset in f2fs_flush_sit_entries -> seg_info_to_raw_sit,
we need to call set_ckpt_valid_blocks() for each updated section?
Thanks,
> + }
> +
> if (err)
> return err;
>
> diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
> index f5d30f32ebdb..e91d944f003a 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
> @@ -347,20 +348,26 @@ 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;
> }
>
> static inline void seg_info_from_raw_sit(struct seg_entry *se,
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [f2fs-dev] [PATCH v3 2/2] f2fs: add ckpt_valid_blocks to the section entry
2025-05-07 8:47 ` Chao Yu
@ 2025-05-07 9:03 ` yohan.joung
0 siblings, 0 replies; 5+ messages in thread
From: yohan.joung @ 2025-05-07 9:03 UTC (permalink / raw)
To: linux-f2fs-devel
Cc: chao, daehojeong, jaegeuk, linux-kernel, pilhyun.kim, yohan.joung
>On 5/7/25 12:30, yohan.joung wrote:
>> 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.joung@sk.com>
>> ---
>> fs/f2fs/segment.c | 29 ++++++++++++++++++++++-------
>> fs/f2fs/segment.h | 29 ++++++++++++++++++-----------
>> 2 files changed, 40 insertions(+), 18 deletions(-)
>>
>> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
>> index 671bc5a8fd4a..09b66a755559 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 +2492,18 @@ 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))
>> + 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
>> @@ -2533,12 +2536,18 @@ static int update_sit_entry_for_alloc(struct f2fs_sb_info *sbi, struct seg_entry
>> * or newly invalidated.
>> */
>> 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++;
>
>What about adding sanity_check_valid_blocks() to check consistency between
>valid blocks of segments and valid blocks of section? Covered w/
>CONFIG_F2FS_CHECK_FS.
I will add it, thanks
>
>> + }
>> }
>>
>> - 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 +2578,9 @@ 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);
>> @@ -5029,6 +5038,12 @@ 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))
>
> unsigned int segno;
>
> for (segno = 0; segno < MAIN_SEGS(sbi);
> segno += SEGS_PER_SEC(sbi))
>
>> + set_ckpt_valid_blocks(sbi, segno);
>
>ckpt_valid_blocks will be reset in f2fs_flush_sit_entries -> seg_info_to_raw_sit,
>we need to call set_ckpt_valid_blocks() for each updated section?
>
>Thanks,
going to add set_ckpt_valid_blocks to seg_info_to_raw_sit
Thanks.
>
>> + }
>> +
>> if (err)
>> return err;
>>
>> diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
>> index f5d30f32ebdb..e91d944f003a 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
>> @@ -347,20 +348,26 @@ 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;
>> }
>>
>> static inline void seg_info_from_raw_sit(struct seg_entry *se,
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2025-05-07 9:03 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
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2025-05-07 4:30 [PATCH v3 1/2] f2fs: add a method for calculating the remaining blocks in the current segment in LFS mode yohan.joung
2025-05-07 4:30 ` [PATCH v3 2/2] f2fs: add ckpt_valid_blocks to the section entry yohan.joung
2025-05-07 8:47 ` Chao Yu
2025-05-07 9:03 ` [f2fs-dev] " yohan.joung
2025-05-07 8:25 ` [PATCH v3 1/2] f2fs: add a method for calculating the remaining blocks in the current segment in LFS mode Chao Yu
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