Skip to content

Commit

Permalink
f2fs: support issuing/waiting discard in range
Browse files Browse the repository at this point in the history 
Fstrim intends to trim invalid blocks of filesystem only with specified
range and granularity, but actually, it will issue all previous cached
discard commands which may be out-of-range and be with unmatched
granularity, it's unneeded.

In order to fix above issues, this patch introduces new helps to support
to issue and wait discard in range and adds a new fstrim_list for tracking
in-flight discard from ->fstrim.

Signed-off-by: Chao Yu <[email protected]>
Signed-off-by: Jaegeuk Kim <[email protected]>
  • Loading branch information
@chaseyu
chaseyu authored and Jaegeuk Kim committed Oct 26, 2017
1 parent 1228b48 commit 8412663
Show file tree
Hide file tree
Showing 3 changed files with 109 additions and 23 deletions.
3 changes: 2 additions & 1 deletion fs/f2fs/f2fs.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -249,6 +249,7 @@ struct discard_cmd_control {
struct list_head pend_list[MAX_PLIST_NUM];/* store pending entries */
unsigned char pend_list_tag[MAX_PLIST_NUM];/* tag for pending entries */
struct list_head wait_list; /* store on-flushing entries */
struct list_head fstrim_list; /* in-flight discard from fstrim */
wait_queue_head_t discard_wait_queue; /* waiting queue for wake-up */
unsigned int discard_wake; /* to wake up discard thread */
struct mutex cmd_lock;
Expand Down Expand Up @@ -2535,7 +2536,7 @@ void invalidate_blocks(struct f2fs_sb_info *sbi, block_t addr);
bool is_checkpointed_data(struct f2fs_sb_info *sbi, block_t blkaddr);
void refresh_sit_entry(struct f2fs_sb_info *sbi, block_t old, block_t new);
void stop_discard_thread(struct f2fs_sb_info *sbi);
void f2fs_wait_discard_bios(struct f2fs_sb_info *sbi, bool umount);
void f2fs_wait_discard_bios(struct f2fs_sb_info *sbi);
void clear_prefree_segments(struct f2fs_sb_info *sbi, struct cp_control *cpc);
void release_discard_addrs(struct f2fs_sb_info *sbi);
int npages_for_summary_flush(struct f2fs_sb_info *sbi, bool for_ra);
Expand Down
127 changes: 106 additions & 21 deletions fs/f2fs/segment.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -873,9 +873,11 @@ void __check_sit_bitmap(struct f2fs_sb_info *sbi,

/* this function is copied from blkdev_issue_discard from block/blk-lib.c */
static void __submit_discard_cmd(struct f2fs_sb_info *sbi,
struct discard_cmd *dc)
struct discard_cmd *dc, bool fstrim)
{
struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
struct list_head *wait_list = fstrim ? &(dcc->fstrim_list) :
&(dcc->wait_list);
struct bio *bio = NULL;

if (dc->state != D_PREP)
Expand All @@ -897,7 +899,7 @@ static void __submit_discard_cmd(struct f2fs_sb_info *sbi,
bio->bi_end_io = f2fs_submit_discard_endio;
bio->bi_opf |= REQ_SYNC;
submit_bio(bio);
list_move_tail(&dc->list, &dcc->wait_list);
list_move_tail(&dc->list, wait_list);
__check_sit_bitmap(sbi, dc->start, dc->start + dc->len);

f2fs_update_iostat(sbi, FS_DISCARD, 1);
Expand Down Expand Up @@ -1082,6 +1084,68 @@ static int __queue_discard_cmd(struct f2fs_sb_info *sbi,
return 0;
}

static void __issue_discard_cmd_range(struct f2fs_sb_info *sbi,
unsigned int start, unsigned int end,
unsigned int granularity)
{
struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
struct discard_cmd *prev_dc = NULL, *next_dc = NULL;
struct rb_node **insert_p = NULL, *insert_parent = NULL;
struct discard_cmd *dc;
struct blk_plug plug;
int issued;

next:
issued = 0;

mutex_lock(&dcc->cmd_lock);
f2fs_bug_on(sbi, !__check_rb_tree_consistence(sbi, &dcc->root));

dc = (struct discard_cmd *)__lookup_rb_tree_ret(&dcc->root,
NULL, start,
(struct rb_entry **)&prev_dc,
(struct rb_entry **)&next_dc,
&insert_p, &insert_parent, true);
if (!dc)
dc = next_dc;

blk_start_plug(&plug);

while (dc && dc->lstart <= end) {
struct rb_node *node;

if (dc->len < granularity)
goto skip;

if (dc->state != D_PREP) {
list_move_tail(&dc->list, &dcc->fstrim_list);
goto skip;
}

__submit_discard_cmd(sbi, dc, true);

if (++issued >= DISCARD_ISSUE_RATE) {
start = dc->lstart + dc->len;

blk_finish_plug(&plug);
mutex_unlock(&dcc->cmd_lock);

schedule();

goto next;
}
skip:
node = rb_next(&dc->rb_node);
dc = rb_entry_safe(node, struct discard_cmd, rb_node);

if (fatal_signal_pending(current))
break;
}

blk_finish_plug(&plug);
mutex_unlock(&dcc->cmd_lock);
}

static int __issue_discard_cmd(struct f2fs_sb_info *sbi, bool issue_cond)
{
struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
Expand All @@ -1104,22 +1168,19 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi, bool issue_cond)

/* Hurry up to finish fstrim */
if (dcc->pend_list_tag[i] & P_TRIM) {
__submit_discard_cmd(sbi, dc);
__submit_discard_cmd(sbi, dc, false);
issued++;

if (fatal_signal_pending(current))
break;
continue;
}

if (!issue_cond) {
__submit_discard_cmd(sbi, dc);
__submit_discard_cmd(sbi, dc, false);
issued++;
continue;
}

if (is_idle(sbi)) {
__submit_discard_cmd(sbi, dc);
__submit_discard_cmd(sbi, dc, false);
issued++;
} else {
io_interrupted = true;
Expand Down Expand Up @@ -1173,10 +1234,14 @@ static void __wait_one_discard_bio(struct f2fs_sb_info *sbi,
mutex_unlock(&dcc->cmd_lock);
}

static void __wait_discard_cmd(struct f2fs_sb_info *sbi, bool wait_cond)
static void __wait_discard_cmd_range(struct f2fs_sb_info *sbi, bool wait_cond,
block_t start, block_t end,
unsigned int granularity,
bool fstrim)
{
struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
struct list_head *wait_list = &(dcc->wait_list);
struct list_head *wait_list = fstrim ? &(dcc->fstrim_list) :
&(dcc->wait_list);
struct discard_cmd *dc, *tmp;
bool need_wait;

Expand All @@ -1185,6 +1250,10 @@ static void __wait_discard_cmd(struct f2fs_sb_info *sbi, bool wait_cond)

mutex_lock(&dcc->cmd_lock);
list_for_each_entry_safe(dc, tmp, wait_list, list) {
if (dc->lstart + dc->len <= start || end <= dc->lstart)
continue;
if (dc->len < granularity)
continue;
if (!wait_cond || (dc->state == D_DONE && !dc->ref)) {
wait_for_completion_io(&dc->wait);
__remove_discard_cmd(sbi, dc);
Expand All @@ -1202,6 +1271,11 @@ static void __wait_discard_cmd(struct f2fs_sb_info *sbi, bool wait_cond)
}
}

static void __wait_all_discard_cmd(struct f2fs_sb_info *sbi, bool wait_cond)
{
__wait_discard_cmd_range(sbi, wait_cond, 0, UINT_MAX, 1, false);
}

/* This should be covered by global mutex, &sit_i->sentry_lock */
void f2fs_wait_discard_bio(struct f2fs_sb_info *sbi, block_t blkaddr)
{
Expand Down Expand Up @@ -1237,12 +1311,12 @@ void stop_discard_thread(struct f2fs_sb_info *sbi)
}
}

/* This comes from f2fs_put_super and f2fs_trim_fs */
void f2fs_wait_discard_bios(struct f2fs_sb_info *sbi, bool umount)
/* This comes from f2fs_put_super */
void f2fs_wait_discard_bios(struct f2fs_sb_info *sbi)
{
__issue_discard_cmd(sbi, false);
__drop_discard_cmd(sbi);
__wait_discard_cmd(sbi, !umount);
__wait_all_discard_cmd(sbi, false);
}

static void mark_discard_range_all(struct f2fs_sb_info *sbi)
Expand Down Expand Up @@ -1286,7 +1360,7 @@ static int issue_discard_thread(void *data)

issued = __issue_discard_cmd(sbi, true);
if (issued) {
__wait_discard_cmd(sbi, true);
__wait_all_discard_cmd(sbi, true);
wait_ms = DEF_MIN_DISCARD_ISSUE_TIME;
} else {
wait_ms = DEF_MAX_DISCARD_ISSUE_TIME;
Expand Down Expand Up @@ -1597,6 +1671,7 @@ static int create_discard_cmd_control(struct f2fs_sb_info *sbi)
dcc->pend_list_tag[i] |= P_ACTIVE;
}
INIT_LIST_HEAD(&dcc->wait_list);
INIT_LIST_HEAD(&dcc->fstrim_list);
mutex_init(&dcc->cmd_lock);
atomic_set(&dcc->issued_discard, 0);
atomic_set(&dcc->issing_discard, 0);
Expand Down Expand Up @@ -2224,7 +2299,8 @@ int f2fs_trim_fs(struct f2fs_sb_info *sbi, struct fstrim_range *range)
{
__u64 start = F2FS_BYTES_TO_BLK(range->start);
__u64 end = start + F2FS_BYTES_TO_BLK(range->len) - 1;
unsigned int start_segno, end_segno;
unsigned int start_segno, end_segno, cur_segno;
block_t start_block, end_block;
struct cp_control cpc;
int err = 0;

Expand All @@ -2245,20 +2321,25 @@ int f2fs_trim_fs(struct f2fs_sb_info *sbi, struct fstrim_range *range)
start_segno = (start <= MAIN_BLKADDR(sbi)) ? 0 : GET_SEGNO(sbi, start);
end_segno = (end >= MAX_BLKADDR(sbi)) ? MAIN_SEGS(sbi) - 1 :
GET_SEGNO(sbi, end);

start_block = START_BLOCK(sbi, start_segno);
end_block = START_BLOCK(sbi, end_segno + 1);

cpc.reason = CP_DISCARD;
cpc.trim_minlen = max_t(__u64, 1, F2FS_BYTES_TO_BLK(range->minlen));

/* do checkpoint to issue discard commands safely */
for (; start_segno <= end_segno; start_segno = cpc.trim_end + 1) {
cpc.trim_start = start_segno;
for (cur_segno = start_segno; cur_segno <= end_segno;
cur_segno = cpc.trim_end + 1) {
cpc.trim_start = cur_segno;

if (sbi->discard_blks == 0)
break;
else if (sbi->discard_blks < BATCHED_TRIM_BLOCKS(sbi))
cpc.trim_end = end_segno;
else
cpc.trim_end = min_t(unsigned int,
rounddown(start_segno +
rounddown(cur_segno +
BATCHED_TRIM_SEGMENTS(sbi),
sbi->segs_per_sec) - 1, end_segno);

Expand All @@ -2270,9 +2351,13 @@ int f2fs_trim_fs(struct f2fs_sb_info *sbi, struct fstrim_range *range)

schedule();
}
/* It's time to issue all the filed discards */
mark_discard_range_all(sbi);
f2fs_wait_discard_bios(sbi, false);

start_block = START_BLOCK(sbi, start_segno);
end_block = START_BLOCK(sbi, min(cur_segno, end_segno) + 1);

__issue_discard_cmd_range(sbi, start_block, end_block, cpc.trim_minlen);
__wait_discard_cmd_range(sbi, true, start_block, end_block,
cpc.trim_minlen, true);
out:
range->len = F2FS_BLK_TO_BYTES(cpc.trimmed);
return err;
Expand Down
2 changes: 1 addition & 1 deletion fs/f2fs/super.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -801,7 +801,7 @@ static void f2fs_put_super(struct super_block *sb)
}

/* be sure to wait for any on-going discard commands */
f2fs_wait_discard_bios(sbi, true);
f2fs_wait_discard_bios(sbi);

if (f2fs_discard_en(sbi) && !sbi->discard_blks) {
struct cp_control cpc = {
Expand Down

0 comments on commit 8412663

Please sign in to comment.