[PATCH 5/5] f2fs: do not __punch_discard_cmd in lfs mode
From: Yunlong Song
Date: Thu Jul 12 2018 - 11:10:55 EST
In lfs mode, it is better to submit and wait for discard of the
new_blkaddr's overall section, rather than punch it which makes
more small discards and is not friendly with flash alignment. And
f2fs does not have to wait discard of each new_blkaddr except for the
start_block of each section with this patch.
Signed-off-by: Yunlong Song <yunlong.song@xxxxxxxxxx>
---
fs/f2fs/segment.c | 76 ++++++++++++++++++++++++++++++++++++++++++++++++++-----
fs/f2fs/segment.h | 7 ++++-
2 files changed, 75 insertions(+), 8 deletions(-)
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index f6c20e0..bce321a 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -893,7 +893,19 @@ static void __remove_discard_cmd(struct f2fs_sb_info *sbi,
static void f2fs_submit_discard_endio(struct bio *bio)
{
struct discard_cmd *dc = (struct discard_cmd *)bio->bi_private;
+ struct f2fs_sb_info *sbi = F2FS_SB(dc->bdev->bd_super);
+ if (test_opt(sbi, LFS)) {
+ unsigned int segno = GET_SEGNO(sbi, dc->lstart);
+ unsigned int secno = GET_SEC_FROM_SEG(sbi, segno);
+ int cnt = (dc->len >> sbi->log_blocks_per_seg) /
+ sbi->segs_per_sec;
+
+ while (cnt--) {
+ set_bit(secno, FREE_I(sbi)->discard_secmap);
+ secno++;
+ }
+ }
dc->error = blk_status_to_errno(bio->bi_status);
dc->state = D_DONE;
complete_all(&dc->wait);
@@ -1349,8 +1361,15 @@ static void f2fs_wait_discard_bio(struct f2fs_sb_info *sbi, block_t blkaddr)
dc = (struct discard_cmd *)f2fs_lookup_rb_tree(&dcc->root,
NULL, blkaddr);
if (dc) {
- if (dc->state == D_PREP) {
+ if (dc->state == D_PREP && !test_opt(sbi, LFS))
__punch_discard_cmd(sbi, dc, blkaddr);
+ else if (dc->state == D_PREP && test_opt(sbi, LFS)) {
+ struct discard_policy dpolicy;
+
+ __init_discard_policy(sbi, &dpolicy, DPOLICY_FORCE, 1);
+ __submit_discard_cmd(sbi, &dpolicy, dc);
+ dc->ref++;
+ need_wait = true;
} else {
dc->ref++;
need_wait = true;
@@ -2071,9 +2090,10 @@ static void get_new_segment(struct f2fs_sb_info *sbi,
unsigned int hint = GET_SEC_FROM_SEG(sbi, *newseg);
unsigned int old_zoneno = GET_ZONE_FROM_SEG(sbi, *newseg);
unsigned int left_start = hint;
- bool init = true;
+ bool init = true, check_discard = test_opt(sbi, LFS) ? true : false;
int go_left = 0;
int i;
+ unsigned long *free_secmap;
spin_lock(&free_i->segmap_lock);
@@ -2084,11 +2104,25 @@ static void get_new_segment(struct f2fs_sb_info *sbi,
goto got_it;
}
find_other_zone:
- secno = find_next_zero_bit(free_i->free_secmap, MAIN_SECS(sbi), hint);
+ if (check_discard) {
+ int entries = f2fs_bitmap_size(MAIN_SECS(sbi)) / sizeof(unsigned long);
+
+ free_secmap = free_i->tmp_secmap;
+ for (i = 0; i < entries; i++)
+ free_secmap[i] = (!(free_i->free_secmap[i] ^
+ free_i->discard_secmap[i])) | free_i->free_secmap[i];
+ } else
+ free_secmap = free_i->free_secmap;
+
+ secno = find_next_zero_bit(free_secmap, MAIN_SECS(sbi), hint);
if (secno >= MAIN_SECS(sbi)) {
if (dir == ALLOC_RIGHT) {
- secno = find_next_zero_bit(free_i->free_secmap,
+ secno = find_next_zero_bit(free_secmap,
MAIN_SECS(sbi), 0);
+ if (secno >= MAIN_SECS(sbi) && check_discard) {
+ check_discard = false;
+ goto find_other_zone;
+ }
f2fs_bug_on(sbi, secno >= MAIN_SECS(sbi));
} else {
go_left = 1;
@@ -2098,13 +2132,17 @@ static void get_new_segment(struct f2fs_sb_info *sbi,
if (go_left == 0)
goto skip_left;
- while (test_bit(left_start, free_i->free_secmap)) {
+ while (test_bit(left_start, free_secmap)) {
if (left_start > 0) {
left_start--;
continue;
}
- left_start = find_next_zero_bit(free_i->free_secmap,
+ left_start = find_next_zero_bit(free_secmap,
MAIN_SECS(sbi), 0);
+ if (left_start >= MAIN_SECS(sbi) && check_discard) {
+ check_discard = false;
+ goto find_other_zone;
+ }
f2fs_bug_on(sbi, left_start >= MAIN_SECS(sbi));
break;
}
@@ -2719,7 +2757,18 @@ void f2fs_allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
*new_blkaddr = NEXT_FREE_BLKADDR(sbi, curseg);
- f2fs_wait_discard_bio(sbi, *new_blkaddr);
+ if (test_opt(sbi, LFS)) {
+ unsigned int start_segno, secno;
+
+ secno = GET_SEC_FROM_SEG(sbi, curseg->segno);
+ start_segno = secno * sbi->segs_per_sec;
+ if (*new_blkaddr == START_BLOCK(sbi, start_segno) &&
+ !test_bit(secno, FREE_I(sbi)->discard_secmap))
+ f2fs_wait_discard_bio(sbi, *new_blkaddr);
+ f2fs_bug_on(sbi, !test_bit(secno, FREE_I(sbi)->discard_secmap));
+ }
+ else
+ f2fs_wait_discard_bio(sbi, *new_blkaddr);
/*
* __add_sum_entry should be resided under the curseg_mutex
@@ -3648,10 +3697,21 @@ static int build_free_segmap(struct f2fs_sb_info *sbi)
if (!free_i->free_secmap)
return -ENOMEM;
+ free_i->discard_secmap = f2fs_kvmalloc(sbi, sec_bitmap_size, GFP_KERNEL);
+ if (!free_i->discard_secmap)
+ return -ENOMEM;
+
+ free_i->tmp_secmap = f2fs_kvmalloc(sbi, sec_bitmap_size, GFP_KERNEL);
+ if (!free_i->tmp_secmap)
+ return -ENOMEM;
+
/* set all segments as dirty temporarily */
memset(free_i->free_segmap, 0xff, bitmap_size);
memset(free_i->free_secmap, 0xff, sec_bitmap_size);
+ /* set all sections as discarded temporarily */
+ memset(free_i->discard_secmap, 0xff, sec_bitmap_size);
+
/* init free segmap information */
free_i->start_segno = GET_SEGNO_FROM_SEG0(sbi, MAIN_BLKADDR(sbi));
free_i->free_segments = 0;
@@ -4047,6 +4107,8 @@ static void destroy_free_segmap(struct f2fs_sb_info *sbi)
SM_I(sbi)->free_info = NULL;
kvfree(free_i->free_segmap);
kvfree(free_i->free_secmap);
+ kvfree(free_i->discard_secmap);
+ kvfree(free_i->tmp_secmap);
kfree(free_i);
}
diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
index 5049551..b37a909 100644
--- a/fs/f2fs/segment.h
+++ b/fs/f2fs/segment.h
@@ -259,6 +259,8 @@ struct free_segmap_info {
spinlock_t segmap_lock; /* free segmap lock */
unsigned long *free_segmap; /* free segment bitmap */
unsigned long *free_secmap; /* free section bitmap */
+ unsigned long *discard_secmap; /* discard section bitmap */
+ unsigned long *tmp_secmap; /* bitmap for temporal use */
};
/* Notice: The order of dirty type is same with CURSEG_XXX in f2fs.h */
@@ -453,8 +455,11 @@ static inline void __set_test_and_free(struct f2fs_sb_info *sbi,
next = find_next_bit(free_i->free_segmap,
start_segno + sbi->segs_per_sec, start_segno);
if (next >= start_segno + sbi->segs_per_sec) {
- if (test_and_clear_bit(secno, free_i->free_secmap))
+ if (test_and_clear_bit(secno, free_i->free_secmap)) {
free_i->free_sections++;
+ if (test_opt(sbi, LFS))
+ clear_bit(secno, free_i->discard_secmap);
+ }
}
}
skip_free:
--
1.8.5.2