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* [PATCH v2] f2fs: add sysfs nodes to get accumulated compression info
@ 2021-03-05  2:24 Daeho Jeong
  2021-03-09  9:22 ` [f2fs-dev] " Chao Yu
  0 siblings, 1 reply; 5+ messages in thread
From: Daeho Jeong @ 2021-03-05  2:24 UTC (permalink / raw)
  To: linux-kernel, linux-f2fs-devel, kernel-team; +Cc: Daeho Jeong

From: Daeho Jeong <daehojeong@google.com>

Added acc_compr_inodes to show accumulated compressed inode count and
acc_compr_blocks to show accumulated secured block count with
compression in sysfs. These can be re-initialized to "0" by writing "0"
value in one of both.

Signed-off-by: Daeho Jeong <daehojeong@google.com>
---
v2: thanks to kernel test robot <lkp@intel.com>, fixed compile issue
    related to kernel config.
---
 Documentation/ABI/testing/sysfs-fs-f2fs | 13 +++++++
 fs/f2fs/checkpoint.c                    |  8 ++++
 fs/f2fs/compress.c                      |  4 +-
 fs/f2fs/data.c                          |  2 +-
 fs/f2fs/f2fs.h                          | 50 ++++++++++++++++++++++++-
 fs/f2fs/file.c                          |  8 ++--
 fs/f2fs/inode.c                         |  1 +
 fs/f2fs/super.c                         | 10 ++++-
 fs/f2fs/sysfs.c                         | 45 ++++++++++++++++++++++
 include/linux/f2fs_fs.h                 |  4 +-
 10 files changed, 135 insertions(+), 10 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs b/Documentation/ABI/testing/sysfs-fs-f2fs
index cbeac1bebe2f..f4fc87503754 100644
--- a/Documentation/ABI/testing/sysfs-fs-f2fs
+++ b/Documentation/ABI/testing/sysfs-fs-f2fs
@@ -409,3 +409,16 @@ Description:	Give a way to change checkpoint merge daemon's io priority.
 		I/O priority "3". We can select the class between "rt" and "be",
 		and set the I/O priority within valid range of it. "," delimiter
 		is necessary in between I/O class and priority number.
+
+What:		/sys/fs/f2fs/<disk>/acc_compr_inodes
+Date:		March 2021
+Contact:	"Daeho Jeong" <daehojeong@google.com>
+Description:	Show accumulated compressed inode count. If you write "0" here,
+		you can initialize acc_compr_inodes and acc_compr_blocks as "0".
+
+What:		/sys/fs/f2fs/<disk>/acc_compr_blocks
+Date:		March 2021
+Contact:	"Daeho Jeong" <daehojeong@google.com>
+Description:	Show accumulated secured block count with compression.
+		If you write "0" here, you can initialize acc_compr_inodes and
+		acc_compr_blocks as "0".
diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index 174a0819ad96..cd944a569162 100644
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -1514,6 +1514,14 @@ static int do_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
 	seg_i->journal->info.kbytes_written = cpu_to_le64(kbytes_written);
 
 	if (__remain_node_summaries(cpc->reason)) {
+		/* Record compression statistics in the hot node summary */
+		spin_lock(&sbi->acc_compr_lock);
+		seg_i->journal->info.acc_compr_blocks =
+			cpu_to_le64(sbi->acc_compr_blocks);
+		seg_i->journal->info.acc_compr_inodes =
+			cpu_to_le32(sbi->acc_compr_inodes);
+		spin_unlock(&sbi->acc_compr_lock);
+
 		f2fs_write_node_summaries(sbi, start_blk);
 		start_blk += NR_CURSEG_NODE_TYPE;
 	}
diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c
index 77fa342de38f..9029e95f4ae4 100644
--- a/fs/f2fs/compress.c
+++ b/fs/f2fs/compress.c
@@ -1351,8 +1351,8 @@ static int f2fs_write_compressed_pages(struct compress_ctx *cc,
 	}
 
 	if (fio.compr_blocks)
-		f2fs_i_compr_blocks_update(inode, fio.compr_blocks - 1, false);
-	f2fs_i_compr_blocks_update(inode, cc->nr_cpages, true);
+		f2fs_i_compr_blocks_update(inode, fio.compr_blocks - 1, false, true);
+	f2fs_i_compr_blocks_update(inode, cc->nr_cpages, true, true);
 
 	set_inode_flag(cc->inode, FI_APPEND_WRITE);
 	if (cc->cluster_idx == 0)
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index b9721c8f116c..d3afb9b0090e 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -2591,7 +2591,7 @@ int f2fs_do_write_data_page(struct f2fs_io_info *fio)
 	ClearPageError(page);
 
 	if (fio->compr_blocks && fio->old_blkaddr == COMPRESS_ADDR)
-		f2fs_i_compr_blocks_update(inode, fio->compr_blocks - 1, false);
+		f2fs_i_compr_blocks_update(inode, fio->compr_blocks - 1, false, true);
 
 	/* LFS mode write path */
 	f2fs_outplace_write_data(&dn, fio);
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index e2d302ae3a46..a12edf5283cd 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1609,6 +1609,11 @@ struct f2fs_sb_info {
 	u64 sectors_written_start;
 	u64 kbytes_written;
 
+	/* For accumulated compression statistics */
+	u64 acc_compr_blocks;
+	u32 acc_compr_inodes;
+	spinlock_t acc_compr_lock;
+
 	/* Reference to checksum algorithm driver via cryptoapi */
 	struct crypto_shash *s_chksum_driver;
 
@@ -3985,6 +3990,43 @@ static inline int __init f2fs_init_compress_cache(void) { return 0; }
 static inline void f2fs_destroy_compress_cache(void) { }
 #endif
 
+#define inc_acc_compr_inodes(inode)					\
+	do {								\
+		struct f2fs_sb_info *sbi = F2FS_I_SB(inode);		\
+		if (f2fs_compressed_file(inode)) {			\
+			spin_lock(&sbi->acc_compr_lock);                \
+			sbi->acc_compr_inodes++;                        \
+			spin_unlock(&sbi->acc_compr_lock);              \
+		}                                                       \
+	} while (0)
+#define dec_acc_compr_inodes(inode)					\
+	do {								\
+		struct f2fs_sb_info *sbi = F2FS_I_SB(inode);		\
+		if (f2fs_compressed_file(inode)) {			\
+			spin_lock(&sbi->acc_compr_lock);		\
+			if (sbi->acc_compr_inodes)			\
+				sbi->acc_compr_inodes--;		\
+			spin_unlock(&sbi->acc_compr_lock);		\
+		}							\
+	} while (0)
+#define add_acc_compr_blocks(inode, blocks)				\
+	do {								\
+		struct f2fs_sb_info *sbi = F2FS_I_SB(inode);		\
+		spin_lock(&sbi->acc_compr_lock);			\
+		sbi->acc_compr_blocks += diff;				\
+		spin_unlock(&sbi->acc_compr_lock);			\
+	} while (0)
+#define sub_acc_compr_blocks(inode, blocks)				\
+	do {								\
+		struct f2fs_sb_info *sbi = F2FS_I_SB(inode);		\
+		spin_lock(&sbi->acc_compr_lock);			\
+		if (sbi->acc_compr_blocks >= diff)			\
+			sbi->acc_compr_blocks -= diff;			\
+		else							\
+			sbi->acc_compr_blocks = 0;			\
+		spin_unlock(&sbi->acc_compr_lock);			\
+	} while (0)
+
 static inline void set_compress_context(struct inode *inode)
 {
 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
@@ -4006,6 +4048,7 @@ static inline void set_compress_context(struct inode *inode)
 	F2FS_I(inode)->i_flags |= F2FS_COMPR_FL;
 	set_inode_flag(inode, FI_COMPRESSED_FILE);
 	stat_inc_compr_inode(inode);
+	inc_acc_compr_inodes(inode);
 	f2fs_mark_inode_dirty_sync(inode, true);
 }
 
@@ -4021,6 +4064,7 @@ static inline bool f2fs_disable_compressed_file(struct inode *inode)
 
 	fi->i_flags &= ~F2FS_COMPR_FL;
 	stat_dec_compr_inode(inode);
+	dec_acc_compr_inodes(inode);
 	clear_inode_flag(inode, FI_COMPRESSED_FILE);
 	f2fs_mark_inode_dirty_sync(inode, true);
 	return true;
@@ -4114,7 +4158,7 @@ static inline bool f2fs_may_compress(struct inode *inode)
 }
 
 static inline void f2fs_i_compr_blocks_update(struct inode *inode,
-						u64 blocks, bool add)
+					u64 blocks, bool add, bool accumulate)
 {
 	int diff = F2FS_I(inode)->i_cluster_size - blocks;
 	struct f2fs_inode_info *fi = F2FS_I(inode);
@@ -4126,9 +4170,13 @@ static inline void f2fs_i_compr_blocks_update(struct inode *inode,
 	if (add) {
 		atomic_add(diff, &fi->i_compr_blocks);
 		stat_add_compr_blocks(inode, diff);
+		if (accumulate)
+			add_acc_compr_blocks(inode, diff);
 	} else {
 		atomic_sub(diff, &fi->i_compr_blocks);
 		stat_sub_compr_blocks(inode, diff);
+		if (accumulate)
+			sub_acc_compr_blocks(inode, diff);
 	}
 	f2fs_mark_inode_dirty_sync(inode, true);
 }
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index d26ff2ae3f5e..6e704383fe86 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -568,7 +568,7 @@ void f2fs_truncate_data_blocks_range(struct dnode_of_data *dn, int count)
 					!(cluster_index & (cluster_size - 1))) {
 			if (compressed_cluster)
 				f2fs_i_compr_blocks_update(dn->inode,
-							valid_blocks, false);
+							valid_blocks, false, true);
 			compressed_cluster = (blkaddr == COMPRESS_ADDR);
 			valid_blocks = 0;
 		}
@@ -597,7 +597,7 @@ void f2fs_truncate_data_blocks_range(struct dnode_of_data *dn, int count)
 	}
 
 	if (compressed_cluster)
-		f2fs_i_compr_blocks_update(dn->inode, valid_blocks, false);
+		f2fs_i_compr_blocks_update(dn->inode, valid_blocks, false, true);
 
 	if (nr_free) {
 		pgoff_t fofs;
@@ -3503,7 +3503,7 @@ static int release_compress_blocks(struct dnode_of_data *dn, pgoff_t count)
 			f2fs_set_data_blkaddr(dn);
 		}
 
-		f2fs_i_compr_blocks_update(dn->inode, compr_blocks, false);
+		f2fs_i_compr_blocks_update(dn->inode, compr_blocks, false, false);
 		dec_valid_block_count(sbi, dn->inode,
 					cluster_size - compr_blocks);
 
@@ -3675,7 +3675,7 @@ static int reserve_compress_blocks(struct dnode_of_data *dn, pgoff_t count)
 		if (reserved != cluster_size - compr_blocks)
 			return -ENOSPC;
 
-		f2fs_i_compr_blocks_update(dn->inode, compr_blocks, true);
+		f2fs_i_compr_blocks_update(dn->inode, compr_blocks, true, false);
 
 		reserved_blocks += reserved;
 next:
diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
index 349d9cb933ee..32a3cbb60409 100644
--- a/fs/f2fs/inode.c
+++ b/fs/f2fs/inode.c
@@ -776,6 +776,7 @@ void f2fs_evict_inode(struct inode *inode)
 			set_sbi_flag(sbi, SBI_QUOTA_NEED_REPAIR);
 	}
 	sb_end_intwrite(inode->i_sb);
+	dec_acc_compr_inodes(inode);
 no_delete:
 	dquot_drop(inode);
 
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 7069793752f1..994895e0d326 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -3861,11 +3861,19 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
 	/* For write statistics */
 	sbi->sectors_written_start = f2fs_get_sectors_written(sbi);
 
+	/* For accumulated compression statistics */
+	spin_lock_init(&sbi->acc_compr_lock);
+
 	/* Read accumulated write IO statistics if exists */
 	seg_i = CURSEG_I(sbi, CURSEG_HOT_NODE);
-	if (__exist_node_summaries(sbi))
+	if (__exist_node_summaries(sbi)) {
 		sbi->kbytes_written =
 			le64_to_cpu(seg_i->journal->info.kbytes_written);
+		sbi->acc_compr_blocks =
+			le64_to_cpu(seg_i->journal->info.acc_compr_blocks);
+		sbi->acc_compr_inodes =
+			le32_to_cpu(seg_i->journal->info.acc_compr_inodes);
+	}
 
 	f2fs_build_gc_manager(sbi);
 
diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
index e38a7f6921dd..cc85a1028e19 100644
--- a/fs/f2fs/sysfs.c
+++ b/fs/f2fs/sysfs.c
@@ -282,6 +282,32 @@ static ssize_t f2fs_sbi_show(struct f2fs_attr *a,
 		return len;
 	}
 
+#ifdef CONFIG_F2FS_FS_COMPRESSION
+	if (!strcmp(a->attr.name, "acc_compr_blocks")) {
+		u64 bcount;
+		int len;
+
+		spin_lock(&sbi->acc_compr_lock);
+		bcount = sbi->acc_compr_blocks;
+		spin_unlock(&sbi->acc_compr_lock);
+
+		len = scnprintf(buf, PAGE_SIZE, "%llu\n", bcount);
+		return len;
+	}
+
+	if (!strcmp(a->attr.name, "acc_compr_inodes")) {
+		u32 icount;
+		int len;
+
+		spin_lock(&sbi->acc_compr_lock);
+		icount = sbi->acc_compr_inodes;
+		spin_unlock(&sbi->acc_compr_lock);
+
+		len = scnprintf(buf, PAGE_SIZE, "%u\n", icount);
+		return len;
+	}
+#endif
+
 	ui = (unsigned int *)(ptr + a->offset);
 
 	return sprintf(buf, "%u\n", *ui);
@@ -458,6 +484,19 @@ static ssize_t __sbi_store(struct f2fs_attr *a,
 		return count;
 	}
 
+#ifdef CONFIG_F2FS_FS_COMPRESSION
+	if (!strcmp(a->attr.name, "acc_compr_blocks") ||
+		!strcmp(a->attr.name, "acc_compr_inodes")) {
+		if (t != 0)
+			return -EINVAL;
+		spin_lock(&sbi->acc_compr_lock);
+		sbi->acc_compr_blocks = 0;
+		sbi->acc_compr_inodes = 0;
+		spin_unlock(&sbi->acc_compr_lock);
+		return count;
+	}
+#endif
+
 	*ui = (unsigned int)t;
 
 	return count;
@@ -668,6 +707,8 @@ F2FS_FEATURE_RO_ATTR(sb_checksum, FEAT_SB_CHECKSUM);
 F2FS_FEATURE_RO_ATTR(casefold, FEAT_CASEFOLD);
 #ifdef CONFIG_F2FS_FS_COMPRESSION
 F2FS_FEATURE_RO_ATTR(compression, FEAT_COMPRESSION);
+F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, acc_compr_blocks, acc_compr_blocks);
+F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, acc_compr_inodes, acc_compr_inodes);
 #endif
 
 #define ATTR_LIST(name) (&f2fs_attr_##name.attr)
@@ -730,6 +771,10 @@ static struct attribute *f2fs_attrs[] = {
 	ATTR_LIST(moved_blocks_foreground),
 	ATTR_LIST(moved_blocks_background),
 	ATTR_LIST(avg_vblocks),
+#endif
+#ifdef CONFIG_F2FS_FS_COMPRESSION
+	ATTR_LIST(acc_compr_blocks),
+	ATTR_LIST(acc_compr_inodes),
 #endif
 	NULL,
 };
diff --git a/include/linux/f2fs_fs.h b/include/linux/f2fs_fs.h
index c6cc0a566ef5..7b707ddeca99 100644
--- a/include/linux/f2fs_fs.h
+++ b/include/linux/f2fs_fs.h
@@ -429,7 +429,7 @@ struct summary_footer {
 /* Reserved area should make size of f2fs_extra_info equals to
  * that of nat_journal and sit_journal.
  */
-#define EXTRA_INFO_RESERVED	(SUM_JOURNAL_SIZE - 2 - 8)
+#define EXTRA_INFO_RESERVED	(SUM_JOURNAL_SIZE - 2 - 20)
 
 /*
  * frequently updated NAT/SIT entries can be stored in the spare area in
@@ -462,6 +462,8 @@ struct sit_journal {
 
 struct f2fs_extra_info {
 	__le64 kbytes_written;
+	__le64 acc_compr_blocks;
+	__le32 acc_compr_inodes;
 	__u8 reserved[EXTRA_INFO_RESERVED];
 } __packed;
 
-- 
2.30.1.766.gb4fecdf3b7-goog


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* Re: [f2fs-dev] [PATCH v2] f2fs: add sysfs nodes to get accumulated compression info
  2021-03-05  2:24 [PATCH v2] f2fs: add sysfs nodes to get accumulated compression info Daeho Jeong
@ 2021-03-09  9:22 ` Chao Yu
  2021-03-09 13:00   ` Daeho Jeong
  0 siblings, 1 reply; 5+ messages in thread
From: Chao Yu @ 2021-03-09  9:22 UTC (permalink / raw)
  To: Daeho Jeong, linux-kernel, linux-f2fs-devel, kernel-team; +Cc: Daeho Jeong

On 2021/3/5 10:24, Daeho Jeong wrote:
> From: Daeho Jeong <daehojeong@google.com>
> 
> Added acc_compr_inodes to show accumulated compressed inode count and
> acc_compr_blocks to show accumulated secured block count with

I noticed that these stat numbers are recorded in extra reserved area in
hot node curseg journal, the journal will be persisted only for umount
or fastboot checkpoint, so the numbers are not so accurate... does this
satisfy your requirement?

> compression in sysfs. These can be re-initialized to "0" by writing "0"
> value in one of both.

Why do we allow reset the stat numbers?

Why not covering all code with macro CONFIG_F2FS_FS_COMPRESSION, since these
numbers are only be updated when we enable compression.

Thanks,

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [f2fs-dev] [PATCH v2] f2fs: add sysfs nodes to get accumulated compression info
  2021-03-09  9:22 ` [f2fs-dev] " Chao Yu
@ 2021-03-09 13:00   ` Daeho Jeong
  2021-03-10  1:31     ` Chao Yu
  0 siblings, 1 reply; 5+ messages in thread
From: Daeho Jeong @ 2021-03-09 13:00 UTC (permalink / raw)
  To: Chao Yu; +Cc: linux-kernel, linux-f2fs-devel, kernel-team, Daeho Jeong

2021년 3월 9일 (화) 오후 6:22, Chao Yu <yuchao0@huawei.com>님이 작성:
>
> On 2021/3/5 10:24, Daeho Jeong wrote:
> > From: Daeho Jeong <daehojeong@google.com>
> >
> > Added acc_compr_inodes to show accumulated compressed inode count and
> > acc_compr_blocks to show accumulated secured block count with
>
> I noticed that these stat numbers are recorded in extra reserved area in
> hot node curseg journal, the journal will be persisted only for umount
> or fastboot checkpoint, so the numbers are not so accurate... does this
> satisfy your requirement?
>

Yes, we are satisfied with just getting rough number of them. But, it
would be better if you suggest more accurate way. :)

> > compression in sysfs. These can be re-initialized to "0" by writing "0"
> > value in one of both.
>
> Why do we allow reset the stat numbers?
>

Actually, I want to have a way to clear any stale number of them, but
I agree we don't need this.

> Why not covering all code with macro CONFIG_F2FS_FS_COMPRESSION, since these
> numbers are only be updated when we enable compression.
>

I wanted to keep the info even in the kernel with doesn't support
per-file compression if those had been written once. What do you
think?

> Thanks,

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [f2fs-dev] [PATCH v2] f2fs: add sysfs nodes to get accumulated compression info
  2021-03-09 13:00   ` Daeho Jeong
@ 2021-03-10  1:31     ` Chao Yu
  2021-03-10  4:30       ` Daeho Jeong
  0 siblings, 1 reply; 5+ messages in thread
From: Chao Yu @ 2021-03-10  1:31 UTC (permalink / raw)
  To: Daeho Jeong; +Cc: linux-kernel, linux-f2fs-devel, kernel-team, Daeho Jeong

On 2021/3/9 21:00, Daeho Jeong wrote:
> 2021년 3월 9일 (화) 오후 6:22, Chao Yu <yuchao0@huawei.com>님이 작성:
>>
>> On 2021/3/5 10:24, Daeho Jeong wrote:
>>> From: Daeho Jeong <daehojeong@google.com>
>>>
>>> Added acc_compr_inodes to show accumulated compressed inode count and
>>> acc_compr_blocks to show accumulated secured block count with
>>
>> I noticed that these stat numbers are recorded in extra reserved area in
>> hot node curseg journal, the journal will be persisted only for umount
>> or fastboot checkpoint, so the numbers are not so accurate... does this
>> satisfy your requirement?
>>
> 
> Yes, we are satisfied with just getting rough number of them. But, it

Alright,

> would be better if you suggest more accurate way. :)

I think this is the cheapest way to store rough number, otherwise it needs to change
f2fs_checkpoint structure layout or add a new inner inode to persist these stat
numbers if we want more accurate one.

> 
>>> compression in sysfs. These can be re-initialized to "0" by writing "0"
>>> value in one of both.
>>
>> Why do we allow reset the stat numbers?
>>
> 
> Actually, I want to have a way to clear any stale number of them, but
> I agree we don't need this.
> 
>> Why not covering all code with macro CONFIG_F2FS_FS_COMPRESSION, since these
>> numbers are only be updated when we enable compression.
>>
> 
> I wanted to keep the info even in the kernel with doesn't support
> per-file compression if those had been written once. What do you
> think?

Sure, if so it's fine to me. :)

Thanks,

> 
>> Thanks,
> .
> 

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [f2fs-dev] [PATCH v2] f2fs: add sysfs nodes to get accumulated compression info
  2021-03-10  1:31     ` Chao Yu
@ 2021-03-10  4:30       ` Daeho Jeong
  0 siblings, 0 replies; 5+ messages in thread
From: Daeho Jeong @ 2021-03-10  4:30 UTC (permalink / raw)
  To: Chao Yu; +Cc: linux-kernel, linux-f2fs-devel, kernel-team, Daeho Jeong

We've reconsidered this feature and decided to get just runtime info
of them, not persistent on disk.
I am re-writing it.

Thanks,

2021년 3월 10일 (수) 오전 10:31, Chao Yu <yuchao0@huawei.com>님이 작성:
>
> On 2021/3/9 21:00, Daeho Jeong wrote:
> > 2021년 3월 9일 (화) 오후 6:22, Chao Yu <yuchao0@huawei.com>님이 작성:
> >>
> >> On 2021/3/5 10:24, Daeho Jeong wrote:
> >>> From: Daeho Jeong <daehojeong@google.com>
> >>>
> >>> Added acc_compr_inodes to show accumulated compressed inode count and
> >>> acc_compr_blocks to show accumulated secured block count with
> >>
> >> I noticed that these stat numbers are recorded in extra reserved area in
> >> hot node curseg journal, the journal will be persisted only for umount
> >> or fastboot checkpoint, so the numbers are not so accurate... does this
> >> satisfy your requirement?
> >>
> >
> > Yes, we are satisfied with just getting rough number of them. But, it
>
> Alright,
>
> > would be better if you suggest more accurate way. :)
>
> I think this is the cheapest way to store rough number, otherwise it needs to change
> f2fs_checkpoint structure layout or add a new inner inode to persist these stat
> numbers if we want more accurate one.
>
> >
> >>> compression in sysfs. These can be re-initialized to "0" by writing "0"
> >>> value in one of both.
> >>
> >> Why do we allow reset the stat numbers?
> >>
> >
> > Actually, I want to have a way to clear any stale number of them, but
> > I agree we don't need this.
> >
> >> Why not covering all code with macro CONFIG_F2FS_FS_COMPRESSION, since these
> >> numbers are only be updated when we enable compression.
> >>
> >
> > I wanted to keep the info even in the kernel with doesn't support
> > per-file compression if those had been written once. What do you
> > think?
>
> Sure, if so it's fine to me. :)
>
> Thanks,
>
> >
> >> Thanks,
> > .
> >

^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2021-03-10  4:32 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-03-05  2:24 [PATCH v2] f2fs: add sysfs nodes to get accumulated compression info Daeho Jeong
2021-03-09  9:22 ` [f2fs-dev] " Chao Yu
2021-03-09 13:00   ` Daeho Jeong
2021-03-10  1:31     ` Chao Yu
2021-03-10  4:30       ` Daeho Jeong

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