Commit b19ee727 authored by liuderong's avatar liuderong Committed by Jaegeuk Kim
Browse files

f2fs: introduce f2fs_get_section_mtime 



When segs_per_sec is larger than 1, section may contain invalid segments,
mtime should be the average value of each valid blocks,
so introduce f2fs_get_section_mtime to
record the average mtime of all valid blocks in a section.

Signed-off-by: default avatarliuderong <liuderong@oppo.com>
Reviewed-by: default avatarChao Yu <chao@kernel.org>
Signed-off-by: default avatarJaegeuk Kim <jaegeuk@kernel.org>
parent eca631b8

fs/f2fs/f2fs.h

+2 −0
Original line number Diff line number Diff line
@@ -3783,6 +3783,8 @@ enum rw_hint f2fs_io_type_to_rw_hint(struct f2fs_sb_info *sbi, 
unsigned int f2fs_usable_segs_in_sec(struct f2fs_sb_info *sbi);

unsigned int f2fs_usable_blks_in_seg(struct f2fs_sb_info *sbi,

			unsigned int segno);

unsigned long long f2fs_get_section_mtime(struct f2fs_sb_info *sbi,

			unsigned int segno);



#define DEF_FRAGMENT_SIZE	4

#define MIN_FRAGMENT_SIZE	1

fs/f2fs/gc.c

+4 −13
Original line number Diff line number Diff line
@@ -361,20 +361,15 @@ static unsigned int check_bg_victims(struct f2fs_sb_info *sbi) 
static unsigned int get_cb_cost(struct f2fs_sb_info *sbi, unsigned int segno)

{

	struct sit_info *sit_i = SIT_I(sbi);

	unsigned int secno = GET_SEC_FROM_SEG(sbi, segno);

	unsigned int start = GET_SEG_FROM_SEC(sbi, secno);

	unsigned long long mtime = 0;

	unsigned int vblocks;

	unsigned char age = 0;

	unsigned char u;

	unsigned int i;

	unsigned int usable_segs_per_sec = f2fs_usable_segs_in_sec(sbi);



	for (i = 0; i < usable_segs_per_sec; i++)

		mtime += get_seg_entry(sbi, start + i)->mtime;

	mtime = f2fs_get_section_mtime(sbi, segno);

	f2fs_bug_on(sbi, mtime == INVALID_MTIME);

	vblocks = get_valid_blocks(sbi, segno, true);



	mtime = div_u64(mtime, usable_segs_per_sec);

	vblocks = div_u64(vblocks, usable_segs_per_sec);



	u = BLKS_TO_SEGS(sbi, vblocks * 100);
@@ -519,10 +514,7 @@ static void add_victim_entry(struct f2fs_sb_info *sbi, 
				struct victim_sel_policy *p, unsigned int segno)

{

	struct sit_info *sit_i = SIT_I(sbi);

	unsigned int secno = GET_SEC_FROM_SEG(sbi, segno);

	unsigned int start = GET_SEG_FROM_SEC(sbi, secno);

	unsigned long long mtime = 0;

	unsigned int i;



	if (unlikely(is_sbi_flag_set(sbi, SBI_CP_DISABLED))) {

		if (p->gc_mode == GC_AT &&
@@ -530,9 +522,8 @@ static void add_victim_entry(struct f2fs_sb_info *sbi, 
			return;

	}



	for (i = 0; i < SEGS_PER_SEC(sbi); i++)

		mtime += get_seg_entry(sbi, start + i)->mtime;

	mtime = div_u64(mtime, SEGS_PER_SEC(sbi));

	mtime = f2fs_get_section_mtime(sbi, segno);

	f2fs_bug_on(sbi, mtime == INVALID_MTIME);



	/* Handle if the system time has changed by the user */

	if (mtime < sit_i->min_mtime)

fs/f2fs/segment.c

+30 −5
Original line number Diff line number Diff line
@@ -5430,6 +5430,35 @@ unsigned int f2fs_usable_segs_in_sec(struct f2fs_sb_info *sbi) 
	return SEGS_PER_SEC(sbi);

}



unsigned long long f2fs_get_section_mtime(struct f2fs_sb_info *sbi,

	unsigned int segno)

{

	unsigned int usable_segs_per_sec = f2fs_usable_segs_in_sec(sbi);

	unsigned int secno = 0, start = 0;

	unsigned int total_valid_blocks = 0;

	unsigned long long mtime = 0;

	unsigned int i = 0;



	secno = GET_SEC_FROM_SEG(sbi, segno);

	start = GET_SEG_FROM_SEC(sbi, secno);



	if (!__is_large_section(sbi))

		return get_seg_entry(sbi, start + i)->mtime;



	for (i = 0; i < usable_segs_per_sec; i++) {

		/* for large section, only check the mtime of valid segments */

		struct seg_entry *se = get_seg_entry(sbi, start+i);



		mtime += se->mtime * se->valid_blocks;

		total_valid_blocks += se->valid_blocks;

	}



	if (total_valid_blocks == 0)

		return INVALID_MTIME;



	return div_u64(mtime, total_valid_blocks);

}



/*

 * Update min, max modified time for cost-benefit GC algorithm

 */
@@ -5443,13 +5472,9 @@ static void init_min_max_mtime(struct f2fs_sb_info *sbi) 
	sit_i->min_mtime = ULLONG_MAX;



	for (segno = 0; segno < MAIN_SEGS(sbi); segno += SEGS_PER_SEC(sbi)) {

		unsigned int i;

		unsigned long long mtime = 0;



		for (i = 0; i < SEGS_PER_SEC(sbi); i++)

			mtime += get_seg_entry(sbi, segno + i)->mtime;



		mtime = div_u64(mtime, SEGS_PER_SEC(sbi));

		mtime = f2fs_get_section_mtime(sbi, segno);



		if (sit_i->min_mtime > mtime)

			sit_i->min_mtime = mtime;

fs/f2fs/segment.h

+2 −0
Original line number Diff line number Diff line
@@ -18,6 +18,8 @@ 
#define F2FS_MIN_SEGMENTS	9 /* SB + 2 (CP + SIT + NAT) + SSA + MAIN */

#define F2FS_MIN_META_SEGMENTS	8 /* SB + 2 (CP + SIT + NAT) + SSA */



#define INVALID_MTIME ULLONG_MAX /* no valid blocks in a segment/section */



/* L: Logical segment # in volume, R: Relative segment # in main area */

#define GET_L2R_SEGNO(free_i, segno)	((segno) - (free_i)->start_segno)

#define GET_R2L_SEGNO(free_i, segno)	((segno) + (free_i)->start_segno)