[PATCH] f2fs: show more debug info for discard pend list

[Yangtao Li]

This patch shows the discard pend list information:

Discard pend list(X:exist .:not exist):
  0   X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X
  32  X X X X . X X . X X X X X X X X X X X X . X X . X X . X X . X X
  64  . . X X . X X . . X . . . X X . X . X . X X . X . X X . . . X .
  96  . X . . . . X . . . . X . . . X X . . . . . . . . . X . . X X .
  128 . X . . . X . . X X X . . . . . X X X . . X . . . . . . . X . X
  160 . . X . . . . . X . . . . . . . . . X . . . X X . . . X . X . .
  192 . . . . . . . . . . . . . . . . X . . . . . . . . . . . . . . .
  224 . X . . . . X . . X . . . . . . . X . . . . . . . X . . . X . .
  256 . . . . . . X . . . . . . . . . . . . . . . . . . . . . . . X .
  288 . . . . . . . . . . X . . . . . . . X . . . . . . . . . . . . .
  320 . . . . . . X X . . X . . . X X . . . . . . . X . . . . . . . .
  352 . . . . . X . . . . . . . . . . . . . . X . . . . . . . . X . .
  384 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . X
  416 X . . . . X . . . . . . . . . . . . . . . . . . . . . . . . . .
  448 . . . . . . . . X . . . . . . . . . . . . . . . . X . . . . . .
  480 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Signed-off-by: Yangtao Li <frank.li@xxxxxxxx>
---
 fs/f2fs/debug.c | 23 +++++++++++++++++++++++
 fs/f2fs/f2fs.h  |  1 +
 2 files changed, 24 insertions(+)

diff --git a/fs/f2fs/debug.c b/fs/f2fs/debug.c
index a216dcdf6941..343e0fa3b1be 100644
--- a/fs/f2fs/debug.c
+++ b/fs/f2fs/debug.c
@@ -109,6 +109,7 @@ static void update_general_status(struct f2fs_sb_info *sbi)
 			llist_empty(&SM_I(sbi)->fcc_info->issue_list);
 	}
 	if (SM_I(sbi)->dcc_info) {
+		struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
 		si->nr_discarded =
 			atomic_read(&SM_I(sbi)->dcc_info->issued_discard);
 		si->nr_discarding =
@@ -116,6 +117,14 @@ static void update_general_status(struct f2fs_sb_info *sbi)
 		si->nr_discard_cmd =
 			atomic_read(&SM_I(sbi)->dcc_info->discard_cmd_cnt);
 		si->undiscard_blks = SM_I(sbi)->dcc_info->undiscard_blks;
+		mutex_lock(&dcc->cmd_lock);
+		for (i = 0; i < MAX_PLIST_NUM; i++) {
+			if (!list_empty(&dcc->pend_list[i]))
+				si->discard_pend_list_exist[i] = true;
+			else
+				si->discard_pend_list_exist[i] = false;
+		}
+		mutex_unlock(&dcc->cmd_lock);
 	}
 	si->nr_issued_ckpt = atomic_read(&sbi->cprc_info.issued_ckpt);
 	si->nr_total_ckpt = atomic_read(&sbi->cprc_info.total_ckpt);
@@ -549,6 +558,20 @@ static int stat_show(struct seq_file *s, void *v)
 		for (j = 0; j < si->util_free; j++)
 			seq_putc(s, '-');
 		seq_puts(s, "]\n\n");
+
+		/* Discard pend list info */
+		if (SM_I(si->sbi)->dcc_info) {
+			seq_puts(s, "Discard pend list(X:exist .:not exist):\n");
+			for (j = 0; j < MAX_PLIST_NUM; j++) {
+				if (j % 32 == 0)
+					seq_printf(s, "  %-3d", j);
+				seq_printf(s, " %c", si->discard_pend_list_exist[j] ? 'X' : '.');
+				if (j % 32 == 31)
+					seq_putc(s, '\n');
+			}
+			seq_putc(s, '\n');
+		}
+
 		seq_printf(s, "IPU: %u blocks\n", si->inplace_count);
 		seq_printf(s, "SSR: %u blocks in %u segments\n",
 			   si->block_count[SSR], si->segment_count[SSR]);
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 2f33d6f23a26..c444f3f86608 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -3875,6 +3875,7 @@ struct f2fs_stat_info {
 	int nr_discarding, nr_discarded;
 	int nr_discard_cmd;
 	unsigned int undiscard_blks;
+	bool discard_pend_list_exist[MAX_PLIST_NUM];
 	int nr_issued_ckpt, nr_total_ckpt, nr_queued_ckpt;
 	unsigned int cur_ckpt_time, peak_ckpt_time;
 	int inline_xattr, inline_inode, inline_dir, append, update, orphans;
-- 
2.25.1