f2fs: zone: introduce first_zoned_segno in f2fs_sb_info

first_zoned_segno() returns a fixed value, let's cache it in
structure f2fs_sb_info to avoid redundant calculation.

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Author: chaseyu

fs/f2fs/f2fs.h

@@ -1759,6 +1759,7 @@ struct f2fs_sb_info {
 	unsigned int dirty_device;		/* for checkpoint data flush */
 	spinlock_t dev_lock;			/* protect dirty_device */
 	bool aligned_blksize;			/* all devices has the same logical blksize */
+	unsigned int first_zoned_segno;		/* first zoned segno */
 
 	/* For write statistics */
 	u64 sectors_written_start;

fs/f2fs/segment.c

@@ -2711,7 +2711,7 @@ static int get_new_segment(struct f2fs_sb_info *sbi,
 		if (sbi->blkzone_alloc_policy == BLKZONE_ALLOC_PRIOR_CONV || pinning)
 			segno = 0;
 		else
-			segno = max(first_zoned_segno(sbi), *newseg);
+			segno = max(sbi->first_zoned_segno, *newseg);
 		hint = GET_SEC_FROM_SEG(sbi, segno);
 	}
 #endif
@@ -2723,7 +2723,7 @@ static int get_new_segment(struct f2fs_sb_info *sbi,
 	if (secno >= MAIN_SECS(sbi) && f2fs_sb_has_blkzoned(sbi)) {
 		/* Write only to sequential zones */
 		if (sbi->blkzone_alloc_policy == BLKZONE_ALLOC_ONLY_SEQ) {
-			hint = GET_SEC_FROM_SEG(sbi, first_zoned_segno(sbi));
+			hint = GET_SEC_FROM_SEG(sbi, sbi->first_zoned_segno);
 			secno = find_next_zero_bit(free_i->free_secmap, MAIN_SECS(sbi), hint);
 		} else
 			secno = find_first_zero_bit(free_i->free_secmap,

fs/f2fs/segment.h

@@ -974,13 +974,3 @@ static inline void wake_up_discard_thread(struct f2fs_sb_info *sbi, bool force)
 	dcc->discard_wake = true;
 	wake_up_interruptible_all(&dcc->discard_wait_queue);
 }
-
-static inline unsigned int first_zoned_segno(struct f2fs_sb_info *sbi)
-{
-	int devi;
-
-	for (devi = 0; devi < sbi->s_ndevs; devi++)
-		if (bdev_is_zoned(FDEV(devi).bdev))
-			return GET_SEGNO(sbi, FDEV(devi).start_blk);
-	return 0;
-}

fs/f2fs/super.c

@@ -4221,6 +4221,16 @@ static void f2fs_record_error_work(struct work_struct *work)
 	f2fs_record_stop_reason(sbi);
 }
 
+static inline unsigned int get_first_zoned_segno(struct f2fs_sb_info *sbi)
+{
+	int devi;
+
+	for (devi = 0; devi < sbi->s_ndevs; devi++)
+		if (bdev_is_zoned(FDEV(devi).bdev))
+			return GET_SEGNO(sbi, FDEV(devi).start_blk);
+	return 0;
+}
+
 static int f2fs_scan_devices(struct f2fs_sb_info *sbi)
 {
 	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
@@ -4621,6 +4631,9 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
 	/* For write statistics */
 	sbi->sectors_written_start = f2fs_get_sectors_written(sbi);
 
+	/* get segno of first zoned block device */
+	sbi->first_zoned_segno = get_first_zoned_segno(sbi);
+
 	/* Read accumulated write IO statistics if exists */
 	seg_i = CURSEG_I(sbi, CURSEG_HOT_NODE);
 	if (__exist_node_summaries(sbi))