[PATCH 18/19] f2fs: introduce discard_map for f2fs_trim_fs

From: Jaegeuk Kim
Date: Fri May 01 2015 - 20:50:46 EST

Next message: Jaegeuk Kim: "[PATCH 16/19] f2fs: split find_data_page according to specific purposes"
Previous message: Alexey Dobriyan: "[PATCH 03/10] parse_integer: convert sscanf()"
In reply to: Jaegeuk Kim: "[PATCH 19/19] f2fs: issue discard with finally produced len and minlen"
Next in thread: Jaegeuk Kim: "[PATCH 16/19] f2fs: split find_data_page according to specific purposes"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

This patch adds a bitmap for discard issues from f2fs_trim_fs.
There-in rule is to issue discard commands only for invalidated blocks
after mount.
Once mount is done, f2fs_trim_fs trims out whole invalid area.
After ehn, it will not issue and discrads redundantly.

Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
---
fs/f2fs/debug.c | 2 +-
fs/f2fs/f2fs.h | 21 +++++++++++++++++++++
fs/f2fs/segment.c | 52 +++++++++++++++++++++++++++++++++++++++-------------
fs/f2fs/segment.h | 1 +
4 files changed, 62 insertions(+), 14 deletions(-)

diff --git a/fs/f2fs/debug.c b/fs/f2fs/debug.c
index f5388f3..f50acbc 100644
--- a/fs/f2fs/debug.c
+++ b/fs/f2fs/debug.c
@@ -143,7 +143,7 @@ static void update_mem_info(struct f2fs_sb_info *sbi)
si->base_mem += sizeof(struct sit_info);
si->base_mem += MAIN_SEGS(sbi) * sizeof(struct seg_entry);
si->base_mem += f2fs_bitmap_size(MAIN_SEGS(sbi));
- si->base_mem += 2 * SIT_VBLOCK_MAP_SIZE * MAIN_SEGS(sbi);
+ si->base_mem += 3 * SIT_VBLOCK_MAP_SIZE * MAIN_SEGS(sbi);
si->base_mem += SIT_VBLOCK_MAP_SIZE;
if (sbi->segs_per_sec > 1)
si->base_mem += MAIN_SECS(sbi) * sizeof(struct sec_entry);
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 78a4300..98fc719 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -117,6 +117,8 @@ enum {
#define DEF_BATCHED_TRIM_SECTIONS 32
#define BATCHED_TRIM_SEGMENTS(sbi) \
(SM_I(sbi)->trim_sections * (sbi)->segs_per_sec)
+#define BATCHED_TRIM_BLOCKS(sbi) \
+ (BATCHED_TRIM_SEGMENTS(sbi) << (sbi)->log_blocks_per_seg)

struct cp_control {
int reason;
@@ -698,6 +700,7 @@ struct f2fs_sb_info {
block_t user_block_count; /* # of user blocks */
block_t total_valid_block_count; /* # of valid blocks */
block_t alloc_valid_block_count; /* # of allocated blocks */
+ block_t discard_blks; /* discard command candidats */
block_t last_valid_block_count; /* for recovery */
u32 s_next_generation; /* for NFS support */
atomic_t nr_pages[NR_COUNT_TYPE]; /* # of pages, see count_type */
@@ -1225,6 +1228,24 @@ static inline int f2fs_test_bit(unsigned int nr, char *addr)
return mask & *addr;
}

+static inline void f2fs_set_bit(unsigned int nr, char *addr)
+{
+ int mask;
+
+ addr += (nr >> 3);
+ mask = 1 << (7 - (nr & 0x07));
+ *addr |= mask;
+}
+
+static inline void f2fs_clear_bit(unsigned int nr, char *addr)
+{
+ int mask;
+
+ addr += (nr >> 3);
+ mask = 1 << (7 - (nr & 0x07));
+ *addr &= ~mask;
+}
+
static inline int f2fs_test_and_set_bit(unsigned int nr, char *addr)
{
int mask;
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index df8bce5..5a4ec01 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -483,10 +483,12 @@ void discard_next_dnode(struct f2fs_sb_info *sbi, block_t blkaddr)
}

static void __add_discard_entry(struct f2fs_sb_info *sbi,
- struct cp_control *cpc, unsigned int start, unsigned int end)
+ struct cp_control *cpc, struct seg_entry *se,
+ unsigned int start, unsigned int end)
{
struct list_head *head = &SM_I(sbi)->discard_list;
struct discard_entry *new, *last;
+ unsigned int i;

if (!list_empty(head)) {
last = list_last_entry(head, struct discard_entry, list);
@@ -504,6 +506,10 @@ static void __add_discard_entry(struct f2fs_sb_info *sbi,
list_add_tail(&new->list, head);
done:
SM_I(sbi)->nr_discards += end - start;
+ for (i = start; i < end; i++) {
+ f2fs_set_bit(i, se->discard_map);
+ sbi->discard_blks--;
+ }
cpc->trimmed += end - start;
}

@@ -514,6 +520,7 @@ static void add_discard_addrs(struct f2fs_sb_info *sbi, struct cp_control *cpc)
struct seg_entry *se = get_seg_entry(sbi, cpc->trim_start);
unsigned long *cur_map = (unsigned long *)se->cur_valid_map;
unsigned long *ckpt_map = (unsigned long *)se->ckpt_valid_map;
+ unsigned long *discard_map = (unsigned long *)se->discard_map;
unsigned long *dmap = SIT_I(sbi)->tmp_map;
unsigned int start = 0, end = -1;
bool force = (cpc->reason == CP_DISCARD);
@@ -523,8 +530,11 @@ static void add_discard_addrs(struct f2fs_sb_info *sbi, struct cp_control *cpc)
SM_I(sbi)->nr_discards >= SM_I(sbi)->max_discards))
return;

- if (force && !se->valid_blocks) {
+ if (!se->valid_blocks) {
struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
+
+ if (!force)
+ return;
/*
* if this segment is registered in the prefree list, then
* we should skip adding a discard candidate, and let the
@@ -537,18 +547,14 @@ static void add_discard_addrs(struct f2fs_sb_info *sbi, struct cp_control *cpc)
return;
}
mutex_unlock(&dirty_i->seglist_lock);
-
- __add_discard_entry(sbi, cpc, 0, sbi->blocks_per_seg);
+ } else if (se->valid_blocks == max_blocks) {
+ /* zero block will be discarded through the prefree list */
return;
}

- /* zero block will be discarded through the prefree list */
- if (!se->valid_blocks || se->valid_blocks == max_blocks)
- return;
-
/* SIT_VBLOCK_MAP_SIZE should be multiple of sizeof(unsigned long) */
for (i = 0; i < entries; i++)
- dmap[i] = force ? ~ckpt_map[i] :
+ dmap[i] = force ? ~ckpt_map[i] & ~discard_map[i] :
(cur_map[i] ^ ckpt_map[i]) & ckpt_map[i];

while (force || SM_I(sbi)->nr_discards <= SM_I(sbi)->max_discards) {
@@ -561,7 +567,7 @@ static void add_discard_addrs(struct f2fs_sb_info *sbi, struct cp_control *cpc)
if (force && end - start < cpc->trim_minlen)
continue;

- __add_discard_entry(sbi, cpc, start, end);
+ __add_discard_entry(sbi, cpc, se, start, end);
}
}

@@ -675,9 +681,13 @@ static void update_sit_entry(struct f2fs_sb_info *sbi, block_t blkaddr, int del)
if (del > 0) {
if (f2fs_test_and_set_bit(offset, se->cur_valid_map))
f2fs_bug_on(sbi, 1);
+ if (f2fs_test_and_set_bit(offset, se->discard_map))
+ sbi->discard_blks--;
} else {
if (!f2fs_test_and_clear_bit(offset, se->cur_valid_map))
f2fs_bug_on(sbi, 1);
+ if (f2fs_test_and_clear_bit(offset, se->discard_map))
+ sbi->discard_blks++;
}
if (!f2fs_test_bit(offset, se->ckpt_valid_map))
se->ckpt_valid_blocks += del;
@@ -1080,7 +1090,14 @@ int f2fs_trim_fs(struct f2fs_sb_info *sbi, struct fstrim_range *range)
/* do checkpoint to issue discard commands safely */
for (; start_segno <= end_segno; start_segno = cpc.trim_end + 1) {
cpc.trim_start = start_segno;
- cpc.trim_end = min_t(unsigned int, rounddown(start_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 +
BATCHED_TRIM_SEGMENTS(sbi),
sbi->segs_per_sec) - 1, end_segno);

@@ -1859,8 +1876,11 @@ static int build_sit_info(struct f2fs_sb_info *sbi)
= kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
sit_i->sentries[start].ckpt_valid_map
= kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
- if (!sit_i->sentries[start].cur_valid_map
- || !sit_i->sentries[start].ckpt_valid_map)
+ sit_i->sentries[start].discard_map
+ = kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
+ if (!sit_i->sentries[start].cur_valid_map ||
+ !sit_i->sentries[start].ckpt_valid_map ||
+ !sit_i->sentries[start].discard_map)
return -ENOMEM;
}

@@ -1998,6 +2018,11 @@ static void build_sit_entries(struct f2fs_sb_info *sbi)
got_it:
check_block_count(sbi, start, &sit);
seg_info_from_raw_sit(se, &sit);
+
+ /* build discard map only one time */
+ memcpy(se->discard_map, se->cur_valid_map, SIT_VBLOCK_MAP_SIZE);
+ sbi->discard_blks += sbi->blocks_per_seg - se->valid_blocks;
+
if (sbi->segs_per_sec > 1) {
struct sec_entry *e = get_sec_entry(sbi, start);
e->valid_blocks += se->valid_blocks;
@@ -2247,6 +2272,7 @@ static void destroy_sit_info(struct f2fs_sb_info *sbi)
for (start = 0; start < MAIN_SEGS(sbi); start++) {
kfree(sit_i->sentries[start].cur_valid_map);
kfree(sit_i->sentries[start].ckpt_valid_map);
+ kfree(sit_i->sentries[start].discard_map);
}
}
kfree(sit_i->tmp_map);
diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
index 85d7fa7..8496357 100644
--- a/fs/f2fs/segment.h
+++ b/fs/f2fs/segment.h
@@ -163,6 +163,7 @@ struct seg_entry {
*/
unsigned short ckpt_valid_blocks;
unsigned char *ckpt_valid_map;
+ unsigned char *discard_map;
unsigned char type; /* segment type like CURSEG_XXX_TYPE */
unsigned long long mtime; /* modification time of the segment */
};
--
2.1.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

Next message: Jaegeuk Kim: "[PATCH 16/19] f2fs: split find_data_page according to specific purposes"
Previous message: Alexey Dobriyan: "[PATCH 03/10] parse_integer: convert sscanf()"
In reply to: Jaegeuk Kim: "[PATCH 19/19] f2fs: issue discard with finally produced len and minlen"
Next in thread: Jaegeuk Kim: "[PATCH 16/19] f2fs: split find_data_page according to specific purposes"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]