Re: [f2fs-dev] [PATCH 6/6] f2fs: show # of on-going flush and discard bios

From: heyunlei
Date: Sat Jan 14 2017 - 02:28:16 EST


Hi Jaegeuk,

On 2017/1/13 6:44, Jaegeuk Kim wrote:
This patch adds stat information for flush and discard commands.

Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
---
fs/f2fs/debug.c | 7 +++++--
fs/f2fs/f2fs.h | 3 ++-
fs/f2fs/segment.c | 4 ++++
3 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/fs/f2fs/debug.c b/fs/f2fs/debug.c
index f9f6b0aeba02..e67cab2fafac 100644
--- a/fs/f2fs/debug.c
+++ b/fs/f2fs/debug.c
@@ -54,6 +54,8 @@ static void update_general_status(struct f2fs_sb_info *sbi)
si->max_aw_cnt = atomic_read(&sbi->max_aw_cnt);
si->nr_wb_cp_data = get_pages(sbi, F2FS_WB_CP_DATA);
si->nr_wb_data = get_pages(sbi, F2FS_WB_DATA);
+ si->nr_flush = atomic_read(&SM_I(sbi)->fcc_info->submit_flush);
+ si->nr_discard = atomic_read(&SM_I(sbi)->dcc_info->submit_discard);
si->total_count = (int)sbi->user_block_count / sbi->blocks_per_seg;
si->rsvd_segs = reserved_segments(sbi);
si->overp_segs = overprovision_segments(sbi);
@@ -318,8 +320,9 @@ static int stat_show(struct seq_file *s, void *v)
seq_printf(s, " - Inner Struct Count: tree: %d(%d), node: %d\n",
si->ext_tree, si->zombie_tree, si->ext_node);
seq_puts(s, "\nBalancing F2FS Async:\n");
- seq_printf(s, " - IO (CP: %4d, Data: %4d)\n",
- si->nr_wb_cp_data, si->nr_wb_data);
+ seq_printf(s, " - IO (CP: %4d, Data: %4d, Flush: %4d, Discard: %4d)\n",
+ si->nr_wb_cp_data, si->nr_wb_data,
+ si->nr_flush, si->nr_discard);
seq_printf(s, " - inmem: %4d, atomic IO: %4d (Max. %4d)\n",
si->inmem_pages, si->aw_cnt, si->max_aw_cnt);
seq_printf(s, " - nodes: %4d in %4d\n",
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index ef5e3709c161..d51bc18e7292 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -201,6 +201,7 @@ struct discard_cmd_control {
wait_queue_head_t discard_wait_queue; /* waiting queue for wake-up */
struct mutex cmd_lock;
int max_discards; /* max. discards to be issued */
+ atomic_t submit_discard; /* # of issued discard */
};

/* for the list of fsync inodes, used only during recovery */
@@ -2254,7 +2255,7 @@ struct f2fs_stat_info {
unsigned int ndirty_dirs, ndirty_files, ndirty_all;
int nats, dirty_nats, sits, dirty_sits, free_nids, alloc_nids;
int total_count, utilization;
- int bg_gc, nr_wb_cp_data, nr_wb_data;
+ int bg_gc, nr_wb_cp_data, nr_wb_data, nr_flush, nr_discard;
int inline_xattr, inline_inode, inline_dir, orphans;
int aw_cnt, max_aw_cnt;
unsigned int valid_count, valid_node_count, valid_inode_count, discard_blks;
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 74364006bfa6..5a2d380182d9 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -653,6 +653,8 @@ static void __remove_discard_cmd(struct f2fs_sb_info *sbi, struct discard_cmd *d
{
int err = dc->bio->bi_error;

+ atomic_dec(&(SM_I(sbi)->dcc_info->submit_discard));
Here submit_discard decrease will include discard command without bio submit.

Thanks.
+
if (err == -EOPNOTSUPP)
err = 0;

@@ -678,6 +680,7 @@ void f2fs_wait_discard_bio(struct f2fs_sb_info *sbi, block_t blkaddr)
if (dc->state == D_PREP) {
dc->state = D_SUBMIT;
submit_bio(dc->bio);
+ atomic_inc(&dcc->submit_discard);
}
wait_for_completion_io(&dc->wait);

@@ -723,6 +726,7 @@ static int issue_discard_thread(void *data)
if (dc->state == D_PREP) {
dc->state = D_SUBMIT;
submit_bio(dc->bio);
+ atomic_inc(&dcc->submit_discard);
if (iter++ > DISCARD_ISSUE_RATE)
break;
} else if (dc->state == D_DONE) {