2022-11-11 17:00:43

by 李扬韬

[permalink] [raw]
Subject: [PATCH v3] f2fs: add proc entry to show discard_plist info

This patch adds a new proc entry to show discard_plist
information in more detail, which is very helpful to
know the discard pend list count clearly.

Such as:

Discard pending list(Show diacrd command count on each entry):
0 4943 138 66 29 21 9 8 12
8 4 7 4 6 3 2 0 1
16 1 2 2 0 0 1 0 0
24 0 1 1 0 0 1 1 0
32 0 1 0 0 0 0 0 0
......

Signed-off-by: Yangtao Li <[email protected]>
---
fs/f2fs/f2fs.h | 1 +
fs/f2fs/segment.c | 22 ++++++++++++++++------
fs/f2fs/sysfs.c | 29 +++++++++++++++++++++++++++++
3 files changed, 46 insertions(+), 6 deletions(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 04ef4cce3d7f..a0226c970cbc 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -405,6 +405,7 @@ struct discard_cmd_control {
wait_queue_head_t discard_wait_queue; /* waiting queue for wake-up */
unsigned int discard_wake; /* to wake up discard thread */
struct mutex cmd_lock;
+ unsigned int nr_pending[MAX_PLIST_NUM]; /* # of pending discards */
unsigned int nr_discards; /* # of discards in the list */
unsigned int max_discards; /* max. discards to be issued */
unsigned int max_discard_request; /* max. discard request per round */
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index aa4be7f25963..72e60d5ee70f 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -921,6 +921,7 @@ static struct discard_cmd *__create_discard_cmd(struct f2fs_sb_info *sbi,
dc->bio_ref = 0;
atomic_inc(&dcc->discard_cmd_cnt);
dcc->undiscard_blks += len;
+ dcc->nr_pending[plist_idx(len)]++;

return dc;
}
@@ -1169,6 +1170,7 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi,
submit_bio(bio);

atomic_inc(&dcc->issued_discard);
+ dcc->nr_pending[plist_idx(len)]--;

f2fs_update_iostat(sbi, NULL, FS_DISCARD, 1);

@@ -1210,9 +1212,11 @@ static void __insert_discard_tree(struct f2fs_sb_info *sbi,
}

static void __relocate_discard_cmd(struct discard_cmd_control *dcc,
- struct discard_cmd *dc)
+ struct discard_cmd *dc, unsigned int index)
{
list_move_tail(&dc->list, &dcc->pend_list[plist_idx(dc->len)]);
+ dcc->nr_pending[plist_idx(dc->len)]++;
+ dcc->nr_pending[index]--;
}

static void __punch_discard_cmd(struct f2fs_sb_info *sbi,
@@ -1230,9 +1234,10 @@ static void __punch_discard_cmd(struct f2fs_sb_info *sbi,
dcc->undiscard_blks -= di.len;

if (blkaddr > di.lstart) {
+ block_t old_len = dc->len;
dc->len = blkaddr - dc->lstart;
dcc->undiscard_blks += dc->len;
- __relocate_discard_cmd(dcc, dc);
+ __relocate_discard_cmd(dcc, dc, plist_idx(old_len));
modified = true;
}

@@ -1243,11 +1248,12 @@ static void __punch_discard_cmd(struct f2fs_sb_info *sbi,
di.lstart + di.len - 1 - blkaddr,
NULL, NULL);
} else {
+ block_t old_len = dc->len;
dc->lstart++;
dc->len--;
dc->start++;
dcc->undiscard_blks += dc->len;
- __relocate_discard_cmd(dcc, dc);
+ __relocate_discard_cmd(dcc, dc, plist_idx(old_len));
}
}
}
@@ -1306,9 +1312,10 @@ static void __update_discard_tree_range(struct f2fs_sb_info *sbi,
prev_dc->bdev == bdev &&
__is_discard_back_mergeable(&di, &prev_dc->di,
max_discard_blocks)) {
+ block_t old_len = prev_dc->di.len;
prev_dc->di.len += di.len;
dcc->undiscard_blks += di.len;
- __relocate_discard_cmd(dcc, prev_dc);
+ __relocate_discard_cmd(dcc, prev_dc, plist_idx(old_len));
di = prev_dc->di;
tdc = prev_dc;
merged = true;
@@ -1318,13 +1325,16 @@ static void __update_discard_tree_range(struct f2fs_sb_info *sbi,
next_dc->bdev == bdev &&
__is_discard_front_mergeable(&di, &next_dc->di,
max_discard_blocks)) {
+ block_t old_len = next_dc->di.len;
next_dc->di.lstart = di.lstart;
next_dc->di.len += di.len;
next_dc->di.start = di.start;
dcc->undiscard_blks += di.len;
- __relocate_discard_cmd(dcc, next_dc);
- if (tdc)
+ __relocate_discard_cmd(dcc, next_dc, plist_idx(old_len));
+ if (tdc) {
+ dcc->nr_pending[plist_idx(tdc->len)]--;
__remove_discard_cmd(sbi, tdc);
+ }
merged = true;
}

diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
index 032c03e09580..2176553f97c9 100644
--- a/fs/f2fs/sysfs.c
+++ b/fs/f2fs/sysfs.c
@@ -1252,6 +1252,32 @@ static int __maybe_unused victim_bits_seq_show(struct seq_file *seq,
return 0;
}

+static int __maybe_unused discard_plist_seq_show(struct seq_file *seq,
+ void *offset)
+{
+ struct super_block *sb = seq->private;
+ struct f2fs_sb_info *sbi = F2FS_SB(sb);
+ struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
+ int i;
+
+ seq_puts(seq, "Discard pending list(Show diacrd command count on each entry):\n");
+ if (!f2fs_realtime_discard_enable(sbi))
+ return 0;
+
+ for (i = 0; i < MAX_PLIST_NUM; i++) {
+ if (i % 8 == 0)
+ seq_printf(seq, "%-10d", i);
+ seq_printf(seq, " %10d", dcc->nr_pending[i]);
+ if (i % 8 == 7)
+ seq_putc(seq, '\n');
+ else
+ seq_putc(seq, ' ');
+ }
+ seq_putc(seq, '\n');
+
+ return 0;
+}
+
int __init f2fs_init_sysfs(void)
{
int ret;
@@ -1322,6 +1348,8 @@ int f2fs_register_sysfs(struct f2fs_sb_info *sbi)
#endif
proc_create_single_data("victim_bits", 0444, sbi->s_proc,
victim_bits_seq_show, sb);
+ proc_create_single_data("discard_plist", 0444, sbi->s_proc,
+ discard_plist_seq_show, sb);
}
return 0;
put_feature_list_kobj:
@@ -1345,6 +1373,7 @@ void f2fs_unregister_sysfs(struct f2fs_sb_info *sbi)
remove_proc_entry("segment_info", sbi->s_proc);
remove_proc_entry("segment_bits", sbi->s_proc);
remove_proc_entry("victim_bits", sbi->s_proc);
+ remove_proc_entry("discard_plist", sbi->s_proc);
remove_proc_entry(sbi->sb->s_id, f2fs_proc_root);
}

--
2.25.1



2022-11-14 23:10:30

by Jaegeuk Kim

[permalink] [raw]
Subject: Re: [PATCH v3] f2fs: add proc entry to show discard_plist info

On 11/11, Yangtao Li wrote:
> This patch adds a new proc entry to show discard_plist
> information in more detail, which is very helpful to
> know the discard pend list count clearly.
>
> Such as:
>
> Discard pending list(Show diacrd command count on each entry):
> 0 4943 138 66 29 21 9 8 12
> 8 4 7 4 6 3 2 0 1
> 16 1 2 2 0 0 1 0 0
> 24 0 1 1 0 0 1 1 0
> 32 0 1 0 0 0 0 0 0
> ......
>
> Signed-off-by: Yangtao Li <[email protected]>
> ---
> fs/f2fs/f2fs.h | 1 +
> fs/f2fs/segment.c | 22 ++++++++++++++++------
> fs/f2fs/sysfs.c | 29 +++++++++++++++++++++++++++++
> 3 files changed, 46 insertions(+), 6 deletions(-)
>
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index 04ef4cce3d7f..a0226c970cbc 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -405,6 +405,7 @@ struct discard_cmd_control {
> wait_queue_head_t discard_wait_queue; /* waiting queue for wake-up */
> unsigned int discard_wake; /* to wake up discard thread */
> struct mutex cmd_lock;
> + unsigned int nr_pending[MAX_PLIST_NUM]; /* # of pending discards */
> unsigned int nr_discards; /* # of discards in the list */
> unsigned int max_discards; /* max. discards to be issued */
> unsigned int max_discard_request; /* max. discard request per round */
> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
> index aa4be7f25963..72e60d5ee70f 100644
> --- a/fs/f2fs/segment.c
> +++ b/fs/f2fs/segment.c
> @@ -921,6 +921,7 @@ static struct discard_cmd *__create_discard_cmd(struct f2fs_sb_info *sbi,
> dc->bio_ref = 0;
> atomic_inc(&dcc->discard_cmd_cnt);
> dcc->undiscard_blks += len;
> + dcc->nr_pending[plist_idx(len)]++;
>
> return dc;
> }
> @@ -1169,6 +1170,7 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi,
> submit_bio(bio);
>
> atomic_inc(&dcc->issued_discard);
> + dcc->nr_pending[plist_idx(len)]--;
>
> f2fs_update_iostat(sbi, NULL, FS_DISCARD, 1);
>
> @@ -1210,9 +1212,11 @@ static void __insert_discard_tree(struct f2fs_sb_info *sbi,
> }
>
> static void __relocate_discard_cmd(struct discard_cmd_control *dcc,
> - struct discard_cmd *dc)
> + struct discard_cmd *dc, unsigned int index)

How about getting all the info?

static void __relocate_discard_cmd(dcc, dc, new_lstart, new_start, new_len)
{
dcc->nr_pending[plist_idx(dc->len)]--;

if (new_lstart)
dc->lstart = new_lstart;
if (new_start)
dc->start = new_start;
dc->len = new_len;
dcc->undiscard_blks += dc->len;
dcc->nr_pending[plist_idx(dc->len)]++;
list_move_tail(&dc->list, &dcc->pend_list[plist_idx(dc->len)]);
}

> {
> list_move_tail(&dc->list, &dcc->pend_list[plist_idx(dc->len)]);
> + dcc->nr_pending[plist_idx(dc->len)]++;
> + dcc->nr_pending[index]--;
> }
>
> static void __punch_discard_cmd(struct f2fs_sb_info *sbi,
> @@ -1230,9 +1234,10 @@ static void __punch_discard_cmd(struct f2fs_sb_info *sbi,
> dcc->undiscard_blks -= di.len;
>
> if (blkaddr > di.lstart) {
> + block_t old_len = dc->len;
> dc->len = blkaddr - dc->lstart;
> dcc->undiscard_blks += dc->len;
> - __relocate_discard_cmd(dcc, dc);
> + __relocate_discard_cmd(dcc, dc, plist_idx(old_len));

__relocate_discard_cmd(dcc, dc, 0, 0, blkaddr - dc->lstart);

> modified = true;
> }
>
> @@ -1243,11 +1248,12 @@ static void __punch_discard_cmd(struct f2fs_sb_info *sbi,
> di.lstart + di.len - 1 - blkaddr,
> NULL, NULL);
> } else {
> + block_t old_len = dc->len;
> dc->lstart++;
> dc->len--;
> dc->start++;
> dcc->undiscard_blks += dc->len;
> - __relocate_discard_cmd(dcc, dc);
> + __relocate_discard_cmd(dcc, dc, plist_idx(old_len));

__relocate_discard_cmd(dcc, dc, dc->lstart + 1, dc->start + 1, dc->len - 1);

> }
> }
> }
> @@ -1306,9 +1312,10 @@ static void __update_discard_tree_range(struct f2fs_sb_info *sbi,
> prev_dc->bdev == bdev &&
> __is_discard_back_mergeable(&di, &prev_dc->di,
> max_discard_blocks)) {
> + block_t old_len = prev_dc->di.len;
> prev_dc->di.len += di.len;
> dcc->undiscard_blks += di.len;
> - __relocate_discard_cmd(dcc, prev_dc);
> + __relocate_discard_cmd(dcc, prev_dc, plist_idx(old_len));

__relocate_discard_cmd(dcc, prev_dc, 0, 0, di.len);

> di = prev_dc->di;
> tdc = prev_dc;
> merged = true;
> @@ -1318,13 +1325,16 @@ static void __update_discard_tree_range(struct f2fs_sb_info *sbi,
> next_dc->bdev == bdev &&
> __is_discard_front_mergeable(&di, &next_dc->di,
> max_discard_blocks)) {
> + block_t old_len = next_dc->di.len;
> next_dc->di.lstart = di.lstart;
> next_dc->di.len += di.len;
> next_dc->di.start = di.start;
> dcc->undiscard_blks += di.len;
> - __relocate_discard_cmd(dcc, next_dc);

__relocate_discard_cmd(dcc, next_dc, di.lstart, di.start, di.len);

> - if (tdc)
> + __relocate_discard_cmd(dcc, next_dc, plist_idx(old_len));
> + if (tdc) {
> + dcc->nr_pending[plist_idx(tdc->len)]--;
> __remove_discard_cmd(sbi, tdc);
> + }
> merged = true;
> }
>
> diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
> index 032c03e09580..2176553f97c9 100644
> --- a/fs/f2fs/sysfs.c
> +++ b/fs/f2fs/sysfs.c
> @@ -1252,6 +1252,32 @@ static int __maybe_unused victim_bits_seq_show(struct seq_file *seq,
> return 0;
> }
>
> +static int __maybe_unused discard_plist_seq_show(struct seq_file *seq,
> + void *offset)
> +{
> + struct super_block *sb = seq->private;
> + struct f2fs_sb_info *sbi = F2FS_SB(sb);
> + struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
> + int i;
> +
> + seq_puts(seq, "Discard pending list(Show diacrd command count on each entry):\n");
> + if (!f2fs_realtime_discard_enable(sbi))
> + return 0;
> +
> + for (i = 0; i < MAX_PLIST_NUM; i++) {
> + if (i % 8 == 0)
> + seq_printf(seq, "%-10d", i);
> + seq_printf(seq, " %10d", dcc->nr_pending[i]);
> + if (i % 8 == 7)
> + seq_putc(seq, '\n');
> + else
> + seq_putc(seq, ' ');
> + }
> + seq_putc(seq, '\n');
> +
> + return 0;
> +}
> +
> int __init f2fs_init_sysfs(void)
> {
> int ret;
> @@ -1322,6 +1348,8 @@ int f2fs_register_sysfs(struct f2fs_sb_info *sbi)
> #endif
> proc_create_single_data("victim_bits", 0444, sbi->s_proc,
> victim_bits_seq_show, sb);
> + proc_create_single_data("discard_plist", 0444, sbi->s_proc,
> + discard_plist_seq_show, sb);
> }
> return 0;
> put_feature_list_kobj:
> @@ -1345,6 +1373,7 @@ void f2fs_unregister_sysfs(struct f2fs_sb_info *sbi)
> remove_proc_entry("segment_info", sbi->s_proc);
> remove_proc_entry("segment_bits", sbi->s_proc);
> remove_proc_entry("victim_bits", sbi->s_proc);
> + remove_proc_entry("discard_plist", sbi->s_proc);
> remove_proc_entry(sbi->sb->s_id, f2fs_proc_root);
> }
>
> --
> 2.25.1