[PATCH RFC 3/5] f2fs: inherit mtime of original block during GC

From: Chao Yu
Date: Tue Jun 30 2020 - 06:05:01 EST


Don't let f2fs inner GC ruins original aging degree of segment.

Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
---
fs/f2fs/data.c | 2 +-
fs/f2fs/f2fs.h | 5 +++--
fs/f2fs/gc.c | 4 ++--
fs/f2fs/segment.c | 55 ++++++++++++++++++++++++++++++++++++-----------
4 files changed, 49 insertions(+), 17 deletions(-)

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index d742f38b1445..062d585fa080 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -1366,7 +1366,7 @@ static int __allocate_data_block(struct dnode_of_data *dn, int seg_type)
set_summary(&sum, dn->nid, dn->ofs_in_node, ni.version);
old_blkaddr = dn->data_blkaddr;
f2fs_allocate_data_block(sbi, NULL, old_blkaddr, &dn->data_blkaddr,
- &sum, seg_type, NULL);
+ &sum, seg_type, NULL, false);
if (GET_SEGNO(sbi, old_blkaddr) != NULL_SEGNO)
invalidate_mapping_pages(META_MAPPING(sbi),
old_blkaddr, old_blkaddr);
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index f06c77066284..a90702a725b6 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -3383,7 +3383,8 @@ void f2fs_outplace_write_data(struct dnode_of_data *dn,
int f2fs_inplace_write_data(struct f2fs_io_info *fio);
void f2fs_do_replace_block(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
block_t old_blkaddr, block_t new_blkaddr,
- bool recover_curseg, bool recover_newaddr);
+ bool recover_curseg, bool recover_newaddr,
+ bool from_gc);
void f2fs_replace_block(struct f2fs_sb_info *sbi, struct dnode_of_data *dn,
block_t old_addr, block_t new_addr,
unsigned char version, bool recover_curseg,
@@ -3391,7 +3392,7 @@ void f2fs_replace_block(struct f2fs_sb_info *sbi, struct dnode_of_data *dn,
void f2fs_allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
block_t old_blkaddr, block_t *new_blkaddr,
struct f2fs_summary *sum, int type,
- struct f2fs_io_info *fio);
+ struct f2fs_io_info *fio, bool from_gc);
void f2fs_wait_on_page_writeback(struct page *page,
enum page_type type, bool ordered, bool locked);
void f2fs_wait_on_block_writeback(struct inode *inode, block_t blkaddr);
diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
index 84807abe4e00..e720886ef9bf 100644
--- a/fs/f2fs/gc.c
+++ b/fs/f2fs/gc.c
@@ -875,7 +875,7 @@ static int move_data_block(struct inode *inode, block_t bidx,
}

f2fs_allocate_data_block(fio.sbi, NULL, fio.old_blkaddr, &newaddr,
- &sum, CURSEG_COLD_DATA, NULL);
+ &sum, CURSEG_COLD_DATA, NULL, true);

fio.encrypted_page = f2fs_pagecache_get_page(META_MAPPING(fio.sbi),
newaddr, FGP_LOCK | FGP_CREAT, GFP_NOFS);
@@ -925,7 +925,7 @@ static int move_data_block(struct inode *inode, block_t bidx,
recover_block:
if (err)
f2fs_do_replace_block(fio.sbi, &sum, newaddr, fio.old_blkaddr,
- true, true);
+ true, true, true);
up_out:
if (lfs_mode)
up_write(&fio.sbi->io_order_lock);
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 906c313835ad..0fde06b904c5 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -2149,12 +2149,28 @@ static void __set_sit_entry_type(struct f2fs_sb_info *sbi, int type,
if (modified)
__mark_sit_entry_dirty(sbi, segno);
}
+static inline unsigned long long get_segment_mtime(struct f2fs_sb_info *sbi,
+ block_t blkaddr)
+{
+ unsigned int segno = GET_SEGNO(sbi, blkaddr);
+
+ if (segno == NULL_SEGNO)
+ return 0;
+ return get_seg_entry(sbi, segno)->mtime;
+}

-static void update_segment_mtime(struct f2fs_sb_info *sbi, block_t blkaddr)
+static void update_segment_mtime(struct f2fs_sb_info *sbi, block_t blkaddr,
+ unsigned long long old_mtime)
{
+ struct seg_entry *se;
unsigned int segno = GET_SEGNO(sbi, blkaddr);
- struct seg_entry *se = get_seg_entry(sbi, segno);
- unsigned long long mtime = get_mtime(sbi, false);
+ unsigned long long ctime = get_mtime(sbi, false);
+ unsigned long long mtime = old_mtime ? old_mtime : ctime;
+
+ if (segno == NULL_SEGNO)
+ return;
+
+ se = get_seg_entry(sbi, segno);

if (!se->mtime) {
se->mtime = mtime;
@@ -2162,8 +2178,8 @@ static void update_segment_mtime(struct f2fs_sb_info *sbi, block_t blkaddr)
se->mtime = (se->mtime * se->valid_blocks + mtime) /
(se->valid_blocks + 1);
}
- if (mtime > SIT_I(sbi)->max_mtime)
- SIT_I(sbi)->max_mtime = mtime;
+ if (ctime > SIT_I(sbi)->max_mtime)
+ SIT_I(sbi)->max_mtime = ctime;
}

static void update_sit_entry(struct f2fs_sb_info *sbi, block_t blkaddr, int del)
@@ -2185,8 +2201,6 @@ static void update_sit_entry(struct f2fs_sb_info *sbi, block_t blkaddr, int del)
f2fs_bug_on(sbi, (new_vblocks >> (sizeof(unsigned short) << 3) ||
(new_vblocks > sbi->blocks_per_seg)));

- update_segment_mtime(sbi, blkaddr);
-
se->valid_blocks = new_vblocks;

/* Update valid block bitmap */
@@ -2280,6 +2294,7 @@ void f2fs_invalidate_blocks(struct f2fs_sb_info *sbi, block_t addr)
/* add it into sit main buffer */
down_write(&sit_i->sentry_lock);

+ update_segment_mtime(sbi, addr, 0);
update_sit_entry(sbi, addr, -1);

/* add it into dirty seglist */
@@ -3188,10 +3203,11 @@ static int __get_segment_type(struct f2fs_io_info *fio)
void f2fs_allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
block_t old_blkaddr, block_t *new_blkaddr,
struct f2fs_summary *sum, int type,
- struct f2fs_io_info *fio)
+ struct f2fs_io_info *fio, bool from_gc)
{
struct sit_info *sit_i = SIT_I(sbi);
struct curseg_info *curseg = CURSEG_I(sbi, type);
+ unsigned long long old_mtime;

down_read(&SM_I(sbi)->curseg_lock);

@@ -3213,6 +3229,14 @@ void f2fs_allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,

stat_inc_block_count(sbi, curseg);

+ if (from_gc) {
+ old_mtime = get_segment_mtime(sbi, old_blkaddr);
+ } else {
+ update_segment_mtime(sbi, old_blkaddr, 0);
+ old_mtime = 0;
+ }
+ update_segment_mtime(sbi, *new_blkaddr, old_mtime);
+
/*
* SIT information should be updated before segment allocation,
* since SSR needs latest valid block information.
@@ -3289,7 +3313,8 @@ static void do_write_page(struct f2fs_summary *sum, struct f2fs_io_info *fio)
down_read(&fio->sbi->io_order_lock);
reallocate:
f2fs_allocate_data_block(fio->sbi, fio->page, fio->old_blkaddr,
- &fio->new_blkaddr, sum, type, fio);
+ &fio->new_blkaddr, sum, type, fio,
+ is_cold_data(fio->page));
if (GET_SEGNO(fio->sbi, fio->old_blkaddr) != NULL_SEGNO)
invalidate_mapping_pages(META_MAPPING(fio->sbi),
fio->old_blkaddr, fio->old_blkaddr);
@@ -3405,7 +3430,8 @@ static inline int __f2fs_get_curseg(struct f2fs_sb_info *sbi,

void f2fs_do_replace_block(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
block_t old_blkaddr, block_t new_blkaddr,
- bool recover_curseg, bool recover_newaddr)
+ bool recover_curseg, bool recover_newaddr,
+ bool from_gc)
{
struct sit_info *sit_i = SIT_I(sbi);
struct curseg_info *curseg;
@@ -3456,11 +3482,16 @@ void f2fs_do_replace_block(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
curseg->next_blkoff = GET_BLKOFF_FROM_SEG0(sbi, new_blkaddr);
__add_sum_entry(sbi, type, sum);

- if (!recover_curseg || recover_newaddr)
+ if (!recover_curseg || recover_newaddr) {
+ if (!from_gc)
+ update_segment_mtime(sbi, new_blkaddr, 0);
update_sit_entry(sbi, new_blkaddr, 1);
+ }
if (GET_SEGNO(sbi, old_blkaddr) != NULL_SEGNO) {
invalidate_mapping_pages(META_MAPPING(sbi),
old_blkaddr, old_blkaddr);
+ if (!from_gc)
+ update_segment_mtime(sbi, old_blkaddr, 0);
update_sit_entry(sbi, old_blkaddr, -1);
}

@@ -3492,7 +3523,7 @@ void f2fs_replace_block(struct f2fs_sb_info *sbi, struct dnode_of_data *dn,
set_summary(&sum, dn->nid, dn->ofs_in_node, version);

f2fs_do_replace_block(sbi, &sum, old_addr, new_addr,
- recover_curseg, recover_newaddr);
+ recover_curseg, recover_newaddr, false);

f2fs_update_data_blkaddr(dn, new_addr);
}
--
2.26.2