f2fs: create gc_no_zoned_gc_percent and gc_boost_zoned_gc_percent

Added control knobs for gc_no_zoned_gc_percent and
gc_boost_zoned_gc_percent.

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Author: Daeho Jeong

Documentation/ABI/testing/sysfs-fs-f2fs

@@ -797,3 +797,17 @@ Date:		September 2024
 Contact:	"Daeho Jeong" <daehojeong@google.com>
 Description:	In order to fine tune GC behavior, we can control the number of
 		reserved segments.
+
+What:		/sys/fs/f2fs/<disk>/gc_no_zoned_gc_percent
+Date:		September 2024
+Contact:	"Daeho Jeong" <daehojeong@google.com>
+Description:	If the percentage of free sections over total sections is above this
+		number, F2FS do not garbage collection for zoned devices through the
+		background GC thread. the default number is "60".
+
+What:		/sys/fs/f2fs/<disk>/gc_boost_zoned_gc_percent
+Date:		September 2024
+Contact:	"Daeho Jeong" <daehojeong@google.com>
+Description:	If the percentage of free sections over total sections is under this
+		number, F2FS boosts garbage collection for zoned devices through the
+		background GC thread. the default number is "25".

fs/f2fs/gc.c

@@ -119,7 +119,8 @@ static int gc_thread_func(void *data)
 		}
 
 		if (f2fs_sb_has_blkzoned(sbi)) {
-			if (has_enough_free_blocks(sbi, LIMIT_NO_ZONED_GC)) {
+			if (has_enough_free_blocks(sbi,
+				gc_th->no_zoned_gc_percent)) {
 				wait_ms = gc_th->no_gc_sleep_time;
 				f2fs_up_write(&sbi->gc_lock);
 				goto next;
@@ -200,10 +201,14 @@ int f2fs_start_gc_thread(struct f2fs_sb_info *sbi)
 		gc_th->min_sleep_time = DEF_GC_THREAD_MIN_SLEEP_TIME_ZONED;
 		gc_th->max_sleep_time = DEF_GC_THREAD_MAX_SLEEP_TIME_ZONED;
 		gc_th->no_gc_sleep_time = DEF_GC_THREAD_NOGC_SLEEP_TIME_ZONED;
+		gc_th->no_zoned_gc_percent = LIMIT_NO_ZONED_GC;
+		gc_th->boost_zoned_gc_percent = LIMIT_BOOST_ZONED_GC;
 	} else {
 		gc_th->min_sleep_time = DEF_GC_THREAD_MIN_SLEEP_TIME;
 		gc_th->max_sleep_time = DEF_GC_THREAD_MAX_SLEEP_TIME;
 		gc_th->no_gc_sleep_time = DEF_GC_THREAD_NOGC_SLEEP_TIME;
+		gc_th->no_zoned_gc_percent = 0;
+		gc_th->boost_zoned_gc_percent = 0;
 	}
 
 	gc_th->gc_wake = false;
@@ -1740,8 +1745,9 @@ static int do_garbage_collect(struct f2fs_sb_info *sbi,
 
 			if (f2fs_sb_has_blkzoned(sbi) &&
 					!has_enough_free_blocks(sbi,
-					LIMIT_BOOST_ZONED_GC))
-				window_granularity *= BOOST_GC_MULTIPLE;
+					sbi->gc_thread->boost_zoned_gc_percent))
+				window_granularity *=
+					BOOST_GC_MULTIPLE;
 
 			end_segno = start_segno + window_granularity;
 		}

fs/f2fs/gc.h

@@ -61,6 +61,10 @@ struct f2fs_gc_kthread {
 						 * caller of f2fs_balance_fs()
 						 * will wait on this wait queue.
 						 */
+
+	/* for gc control for zoned devices */
+	unsigned int no_zoned_gc_percent;
+	unsigned int boost_zoned_gc_percent;
 };
 
 struct gc_inode_list {

fs/f2fs/sysfs.c

@@ -977,6 +977,8 @@ GC_THREAD_RW_ATTR(gc_urgent_sleep_time, urgent_sleep_time);
 GC_THREAD_RW_ATTR(gc_min_sleep_time, min_sleep_time);
 GC_THREAD_RW_ATTR(gc_max_sleep_time, max_sleep_time);
 GC_THREAD_RW_ATTR(gc_no_gc_sleep_time, no_gc_sleep_time);
+GC_THREAD_RW_ATTR(gc_no_zoned_gc_percent, no_zoned_gc_percent);
+GC_THREAD_RW_ATTR(gc_boost_zoned_gc_percent, boost_zoned_gc_percent);
 
 /* SM_INFO ATTR */
 SM_INFO_RW_ATTR(reclaim_segments, rec_prefree_segments);
@@ -1137,6 +1139,8 @@ static struct attribute *f2fs_attrs[] = {
 	ATTR_LIST(gc_min_sleep_time),
 	ATTR_LIST(gc_max_sleep_time),
 	ATTR_LIST(gc_no_gc_sleep_time),
+	ATTR_LIST(gc_no_zoned_gc_percent),
+	ATTR_LIST(gc_boost_zoned_gc_percent),
 	ATTR_LIST(gc_idle),
 	ATTR_LIST(gc_urgent),
 	ATTR_LIST(reclaim_segments),