Re: [PATCH v2] f2fs: introduce cur_reserved_blocks in sysfs

2017-10-25 Thread Yunlong Song 

Hi, Chao,

ping...

Please see the review comment below. And the change is already in the v3 
patch.


On 2017/8/18 23:16, Yunlong Song wrote:

I send a v3 patch, please review, and the main difference is shown below.

On 2017/8/18 18:20, Chao Yu wrote:

Hi Yunlong,

IMO, we don't need additional sysfs entry, how about changing a bit 
as below?


>From 3fc8206871fe457859f1537c9dc8918b45f14601 Mon Sep 17 00:00:00 2001
From: Yunlong Song 
Date: Wed, 16 Aug 2017 23:01:56 +0800
Subject: [PATCH] f2fs: support soft block reservation

It supports to extend reserved_blocks sysfs interface to be soft
threshold, which allows user configure it exceeding current available
user space.

Signed-off-by: Yunlong Song 
Signed-off-by: Chao Yu 
---
  Documentation/ABI/testing/sysfs-fs-f2fs |  3 ++-
  fs/f2fs/f2fs.h  | 12 ++--
  fs/f2fs/super.c |  3 ++-
  fs/f2fs/sysfs.c | 16 ++--
  4 files changed, 28 insertions(+), 6 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs 
b/Documentation/ABI/testing/sysfs-fs-f2fs

index 11b7f4ebea7c..45c3d92f77c8 100644
--- a/Documentation/ABI/testing/sysfs-fs-f2fs
+++ b/Documentation/ABI/testing/sysfs-fs-f2fs
@@ -138,7 +138,8 @@ What: /sys/fs/f2fs//reserved_blocks
  Date:June 2017
  Contact:"Chao Yu" 
  Description:
- Controls current reserved blocks in system.
+ Controls current reserved blocks in system, the threshold
+ is soft, it could exceed current avaible user space.

  What:/sys/fs/f2fs//gc_urgent
  Date:August 2017
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 336021b9b93e..a7b2d257e8ee 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1046,6 +1046,7 @@ struct f2fs_sb_info {
  block_t discard_blks;/* discard command candidats */
  block_t last_valid_block_count;/* for recovery */
  block_t reserved_blocks;/* configurable reserved blocks */
+block_t current_reserved_blocks;/* current reserved blocks */

  u32 s_next_generation;/* for NFS support */

@@ -1520,7 +1521,8 @@ static inline int inc_valid_block_count(struct 
f2fs_sb_info *sbi,


  spin_lock(&sbi->stat_lock);
  sbi->total_valid_block_count += (block_t)(*count);
-avail_user_block_count = sbi->user_block_count - 
sbi->reserved_blocks;

+avail_user_block_count = sbi->user_block_count -
+sbi->current_reserved_blocks;
  if (unlikely(sbi->total_valid_block_count > 
avail_user_block_count)) {

  diff = sbi->total_valid_block_count - avail_user_block_count;
  *count -= diff;
@@ -1554,6 +1556,9 @@ static inline void dec_valid_block_count(struct 
f2fs_sb_info *sbi,

  f2fs_bug_on(sbi, sbi->total_valid_block_count < (block_t) count);
  f2fs_bug_on(sbi, inode->i_blocks < sectors);
  sbi->total_valid_block_count -= (block_t)count;
+if (sbi->reserved_blocks)

Add sbi->reserved_blocks != sbi->cur_reserved_blocks check

+sbi->current_reserved_blocks = min(sbi->reserved_blocks,
+sbi->current_reserved_blocks + count);
  spin_unlock(&sbi->stat_lock);
  f2fs_i_blocks_write(inode, count, false, true);
  }
@@ -1700,7 +1705,7 @@ static inline int inc_valid_node_count(struct 
f2fs_sb_info *sbi,

  spin_lock(&sbi->stat_lock);

  valid_block_count = sbi->total_valid_block_count + 1;
-if (unlikely(valid_block_count + sbi->reserved_blocks >
+if (unlikely(valid_block_count + sbi->current_reserved_blocks >
  sbi->user_block_count)) {
  spin_unlock(&sbi->stat_lock);
  goto enospc;
@@ -1743,6 +1748,9 @@ static inline void dec_valid_node_count(struct 
f2fs_sb_info *sbi,


  sbi->total_valid_node_count--;
  sbi->total_valid_block_count--;
+if (sbi->reserved_blocks)
+sbi->current_reserved_blocks = min(sbi->reserved_blocks,
+sbi->current_reserved_blocks + 1);

change to sbi->cur_reserved_blocks++;


  spin_unlock(&sbi->stat_lock);

diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 4c1bdcb94133..036f083bbf56 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -957,7 +957,7 @@ static int f2fs_statfs(struct dentry *dentry, 
struct kstatfs *buf)

  buf->f_blocks = total_count - start_count;
  buf->f_bfree = user_block_count - valid_user_blocks(sbi) + 
ovp_count;

  buf->f_bavail = user_block_count - valid_user_blocks(sbi) -
-sbi->reserved_blocks;
+sbi->current_reserved_blocks;

  avail_node_count = sbi->total_node_count - F2FS_RESERVED_NODE_NUM;

@@ -2411,6 +2411,7 @@ static int f2fs_fill_super(struct super_block 
*sb, void *data, int silent)

le64_to_cpu(sbi->ckpt->valid_block_count);
  sbi->last_valid_block_count = sbi->total_valid_block_count;
  sbi->reserved_blocks = 0;
+sbi->current_reserved_blocks = 0;

  for (i = 0; i < NR_INODE_TYPE; i++) {

Re: [PATCH v2] f2fs: introduce cur_reserved_blocks in sysfs

2017-08-18 Thread Yunlong Song 

I send a v3 patch, please review, and the main difference is shown below.

On 2017/8/18 18:20, Chao Yu wrote:

Hi Yunlong,

IMO, we don't need additional sysfs entry, how about changing a bit as below?

>From 3fc8206871fe457859f1537c9dc8918b45f14601 Mon Sep 17 00:00:00 2001
From: Yunlong Song 
Date: Wed, 16 Aug 2017 23:01:56 +0800
Subject: [PATCH] f2fs: support soft block reservation

It supports to extend reserved_blocks sysfs interface to be soft
threshold, which allows user configure it exceeding current available
user space.

Signed-off-by: Yunlong Song 
Signed-off-by: Chao Yu 
---
  Documentation/ABI/testing/sysfs-fs-f2fs |  3 ++-
  fs/f2fs/f2fs.h  | 12 ++--
  fs/f2fs/super.c |  3 ++-
  fs/f2fs/sysfs.c | 16 ++--
  4 files changed, 28 insertions(+), 6 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs 
b/Documentation/ABI/testing/sysfs-fs-f2fs
index 11b7f4ebea7c..45c3d92f77c8 100644
--- a/Documentation/ABI/testing/sysfs-fs-f2fs
+++ b/Documentation/ABI/testing/sysfs-fs-f2fs
@@ -138,7 +138,8 @@ What:   /sys/fs/f2fs//reserved_blocks
  Date: June 2017
  Contact:  "Chao Yu" 
  Description:
-Controls current reserved blocks in system.
+Controls current reserved blocks in system, the threshold
+is soft, it could exceed current avaible user space.

  What: /sys/fs/f2fs//gc_urgent
  Date: August 2017
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 336021b9b93e..a7b2d257e8ee 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1046,6 +1046,7 @@ struct f2fs_sb_info {
block_t discard_blks;   /* discard command candidats */
block_t last_valid_block_count; /* for recovery */
block_t reserved_blocks;/* configurable reserved blocks 
*/
+   block_t current_reserved_blocks;/* current reserved blocks */

u32 s_next_generation;  /* for NFS support */

@@ -1520,7 +1521,8 @@ static inline int inc_valid_block_count(struct 
f2fs_sb_info *sbi,

spin_lock(&sbi->stat_lock);
sbi->total_valid_block_count += (block_t)(*count);
-   avail_user_block_count = sbi->user_block_count - sbi->reserved_blocks;
+   avail_user_block_count = sbi->user_block_count -
+   sbi->current_reserved_blocks;
if (unlikely(sbi->total_valid_block_count > avail_user_block_count)) {
diff = sbi->total_valid_block_count - avail_user_block_count;
*count -= diff;
@@ -1554,6 +1556,9 @@ static inline void dec_valid_block_count(struct 
f2fs_sb_info *sbi,
f2fs_bug_on(sbi, sbi->total_valid_block_count < (block_t) count);
f2fs_bug_on(sbi, inode->i_blocks < sectors);
sbi->total_valid_block_count -= (block_t)count;
+   if (sbi->reserved_blocks)

Add sbi->reserved_blocks != sbi->cur_reserved_blocks check

+   sbi->current_reserved_blocks = min(sbi->reserved_blocks,
+   sbi->current_reserved_blocks + count);
spin_unlock(&sbi->stat_lock);
f2fs_i_blocks_write(inode, count, false, true);
  }
@@ -1700,7 +1705,7 @@ static inline int inc_valid_node_count(struct 
f2fs_sb_info *sbi,
spin_lock(&sbi->stat_lock);

valid_block_count = sbi->total_valid_block_count + 1;
-   if (unlikely(valid_block_count + sbi->reserved_blocks >
+   if (unlikely(valid_block_count + sbi->current_reserved_blocks >
sbi->user_block_count)) {
spin_unlock(&sbi->stat_lock);
goto enospc;
@@ -1743,6 +1748,9 @@ static inline void dec_valid_node_count(struct 
f2fs_sb_info *sbi,

sbi->total_valid_node_count--;
sbi->total_valid_block_count--;
+   if (sbi->reserved_blocks)
+   sbi->current_reserved_blocks = min(sbi->reserved_blocks,
+   sbi->current_reserved_blocks + 1);

change to sbi->cur_reserved_blocks++;


spin_unlock(&sbi->stat_lock);

diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 4c1bdcb94133..036f083bbf56 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -957,7 +957,7 @@ static int f2fs_statfs(struct dentry *dentry, struct 
kstatfs *buf)
buf->f_blocks = total_count - start_count;
buf->f_bfree = user_block_count - valid_user_blocks(sbi) + ovp_count;
buf->f_bavail = user_block_count - valid_user_blocks(sbi) -
-   sbi->reserved_blocks;
+   sbi->current_reserved_blocks;

avail_node_count = sbi->total_node_count - F2FS_RESERVED_NODE_NUM;

@@ -2411,6 +2411,7 @@ static int f2fs_fill_super(struct super_block *sb, void 
*data, int silent)
le64_to_cpu(sbi->ckpt->valid_block_count);
sbi->last_

Re: [PATCH v2] f2fs: introduce cur_reserved_blocks in sysfs

2017-08-18 Thread Chao Yu 
Hi Yunlong,

IMO, we don't need additional sysfs entry, how about changing a bit as below?

>From 3fc8206871fe457859f1537c9dc8918b45f14601 Mon Sep 17 00:00:00 2001
From: Yunlong Song 
Date: Wed, 16 Aug 2017 23:01:56 +0800
Subject: [PATCH] f2fs: support soft block reservation

It supports to extend reserved_blocks sysfs interface to be soft
threshold, which allows user configure it exceeding current available
user space.

Signed-off-by: Yunlong Song 
Signed-off-by: Chao Yu 
---
 Documentation/ABI/testing/sysfs-fs-f2fs |  3 ++-
 fs/f2fs/f2fs.h  | 12 ++--
 fs/f2fs/super.c |  3 ++-
 fs/f2fs/sysfs.c | 16 ++--
 4 files changed, 28 insertions(+), 6 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs 
b/Documentation/ABI/testing/sysfs-fs-f2fs
index 11b7f4ebea7c..45c3d92f77c8 100644
--- a/Documentation/ABI/testing/sysfs-fs-f2fs
+++ b/Documentation/ABI/testing/sysfs-fs-f2fs
@@ -138,7 +138,8 @@ What:   /sys/fs/f2fs//reserved_blocks
 Date:  June 2017
 Contact:   "Chao Yu" 
 Description:
-Controls current reserved blocks in system.
+Controls current reserved blocks in system, the threshold
+is soft, it could exceed current avaible user space.

 What:  /sys/fs/f2fs//gc_urgent
 Date:  August 2017
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 336021b9b93e..a7b2d257e8ee 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1046,6 +1046,7 @@ struct f2fs_sb_info {
block_t discard_blks;   /* discard command candidats */
block_t last_valid_block_count; /* for recovery */
block_t reserved_blocks;/* configurable reserved blocks 
*/
+   block_t current_reserved_blocks;/* current reserved blocks */

u32 s_next_generation;  /* for NFS support */

@@ -1520,7 +1521,8 @@ static inline int inc_valid_block_count(struct 
f2fs_sb_info *sbi,

spin_lock(&sbi->stat_lock);
sbi->total_valid_block_count += (block_t)(*count);
-   avail_user_block_count = sbi->user_block_count - sbi->reserved_blocks;
+   avail_user_block_count = sbi->user_block_count -
+   sbi->current_reserved_blocks;
if (unlikely(sbi->total_valid_block_count > avail_user_block_count)) {
diff = sbi->total_valid_block_count - avail_user_block_count;
*count -= diff;
@@ -1554,6 +1556,9 @@ static inline void dec_valid_block_count(struct 
f2fs_sb_info *sbi,
f2fs_bug_on(sbi, sbi->total_valid_block_count < (block_t) count);
f2fs_bug_on(sbi, inode->i_blocks < sectors);
sbi->total_valid_block_count -= (block_t)count;
+   if (sbi->reserved_blocks)
+   sbi->current_reserved_blocks = min(sbi->reserved_blocks,
+   sbi->current_reserved_blocks + count);
spin_unlock(&sbi->stat_lock);
f2fs_i_blocks_write(inode, count, false, true);
 }
@@ -1700,7 +1705,7 @@ static inline int inc_valid_node_count(struct 
f2fs_sb_info *sbi,
spin_lock(&sbi->stat_lock);

valid_block_count = sbi->total_valid_block_count + 1;
-   if (unlikely(valid_block_count + sbi->reserved_blocks >
+   if (unlikely(valid_block_count + sbi->current_reserved_blocks >
sbi->user_block_count)) {
spin_unlock(&sbi->stat_lock);
goto enospc;
@@ -1743,6 +1748,9 @@ static inline void dec_valid_node_count(struct 
f2fs_sb_info *sbi,

sbi->total_valid_node_count--;
sbi->total_valid_block_count--;
+   if (sbi->reserved_blocks)
+   sbi->current_reserved_blocks = min(sbi->reserved_blocks,
+   sbi->current_reserved_blocks + 1);

spin_unlock(&sbi->stat_lock);

diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 4c1bdcb94133..036f083bbf56 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -957,7 +957,7 @@ static int f2fs_statfs(struct dentry *dentry, struct 
kstatfs *buf)
buf->f_blocks = total_count - start_count;
buf->f_bfree = user_block_count - valid_user_blocks(sbi) + ovp_count;
buf->f_bavail = user_block_count - valid_user_blocks(sbi) -
-   sbi->reserved_blocks;
+   sbi->current_reserved_blocks;

avail_node_count = sbi->total_node_count - F2FS_RESERVED_NODE_NUM;

@@ -2411,6 +2411,7 @@ static int f2fs_fill_super(struct super_block *sb, void 
*data, int silent)
le64_to_cpu(sbi->ckpt->valid_block_count);
sbi->last_valid_block_count = sbi->total_valid_block_count;
sbi->reserved_blocks = 0;
+   sbi->current_reserved_blocks = 0;

for (i = 0; i < NR_INODE_TYPE; i++) {
INIT_LIST_HEAD(&sbi->inode_list

Re: [PATCH v2] f2fs: introduce cur_reserved_blocks in sysfs

2017-08-18 Thread Yunlong Song 

ping...

On 2017/8/15 12:08, Yunlong Song wrote:

ping...

On 2017/8/11 19:43, Yunlong Song wrote:
In this patch, we add a new sysfs interface, we can use it to 
gradually achieve
the reserved_blocks finally, even when reserved_blocks is initially 
set over
user_block_count - total_valid_block_count. This is very useful, 
especially when
we upgrade kernel with new reserved_blocks value, but old disk image 
unluckily has
user_block_count - total_valid_block_count smaller than the desired 
reserved_blocks.
With this patch, f2fs can try its best to reserve space and get close 
to the
reserved_blocks, and the current value of achieved reserved_blocks 
can be shown

in real time.

To ensure there is enough space for supporting system's activation, 
we safely
increase cur_reserved_blocks in dev_valid_block(,node)_count to only 
take up the

blocks which are just obsoleted.

Signed-off-by: Yunlong Song 
---
  Documentation/ABI/testing/sysfs-fs-f2fs |  6 ++
  fs/f2fs/f2fs.h  |  9 +++--
  fs/f2fs/super.c |  3 ++-
  fs/f2fs/sysfs.c | 15 ++-
  4 files changed, 25 insertions(+), 8 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs 
b/Documentation/ABI/testing/sysfs-fs-f2fs

index 11b7f4e..bdbb9f3 100644
--- a/Documentation/ABI/testing/sysfs-fs-f2fs
+++ b/Documentation/ABI/testing/sysfs-fs-f2fs
@@ -151,3 +151,9 @@ Date:August 2017
  Contact:"Jaegeuk Kim" 
  Description:
   Controls sleep time of GC urgent mode
+
+What:/sys/fs/f2fs//cur_reserved_blocks
+Date:August 2017
+Contact:"Yunlong Song" 
+Description:
+ Shows current reserved blocks in system.
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 2f20b6b..62d7343 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1041,6 +1041,7 @@ struct f2fs_sb_info {
  block_t discard_blks;/* discard command candidats */
  block_t last_valid_block_count;/* for recovery */
  block_t reserved_blocks;/* configurable reserved blocks */
+block_t cur_reserved_blocks;/* current reserved blocks */
u32 s_next_generation;/* for NFS support */
  @@ -1515,7 +1516,7 @@ static inline int 
inc_valid_block_count(struct f2fs_sb_info *sbi,

spin_lock(&sbi->stat_lock);
  sbi->total_valid_block_count += (block_t)(*count);
-avail_user_block_count = sbi->user_block_count - 
sbi->reserved_blocks;
+avail_user_block_count = sbi->user_block_count - 
sbi->cur_reserved_blocks;
  if (unlikely(sbi->total_valid_block_count > 
avail_user_block_count)) {

  diff = sbi->total_valid_block_count - avail_user_block_count;
  *count -= diff;
@@ -1549,6 +1550,8 @@ static inline void dec_valid_block_count(struct 
f2fs_sb_info *sbi,

  f2fs_bug_on(sbi, sbi->total_valid_block_count < (block_t) count);
  f2fs_bug_on(sbi, inode->i_blocks < sectors);
  sbi->total_valid_block_count -= (block_t)count;
+sbi->cur_reserved_blocks = min(sbi->reserved_blocks,
+sbi->cur_reserved_blocks + count);
  spin_unlock(&sbi->stat_lock);
  f2fs_i_blocks_write(inode, count, false, true);
  }
@@ -1695,7 +1698,7 @@ static inline int inc_valid_node_count(struct 
f2fs_sb_info *sbi,

  spin_lock(&sbi->stat_lock);
valid_block_count = sbi->total_valid_block_count + 1;
-if (unlikely(valid_block_count + sbi->reserved_blocks >
+if (unlikely(valid_block_count + sbi->cur_reserved_blocks >
  sbi->user_block_count)) {
  spin_unlock(&sbi->stat_lock);
  goto enospc;
@@ -1738,6 +1741,8 @@ static inline void dec_valid_node_count(struct 
f2fs_sb_info *sbi,

sbi->total_valid_node_count--;
  sbi->total_valid_block_count--;
+sbi->cur_reserved_blocks = min(sbi->reserved_blocks,
+sbi->cur_reserved_blocks + 1);
spin_unlock(&sbi->stat_lock);
  diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 4c1bdcb..16a805f 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -957,7 +957,7 @@ static int f2fs_statfs(struct dentry *dentry, 
struct kstatfs *buf)

  buf->f_blocks = total_count - start_count;
  buf->f_bfree = user_block_count - valid_user_blocks(sbi) + 
ovp_count;

  buf->f_bavail = user_block_count - valid_user_blocks(sbi) -
-sbi->reserved_blocks;
+sbi->cur_reserved_blocks;
avail_node_count = sbi->total_node_count - 
F2FS_RESERVED_NODE_NUM;
  @@ -2411,6 +2411,7 @@ static int f2fs_fill_super(struct super_block 
*sb, void *data, int silent)

le64_to_cpu(sbi->ckpt->valid_block_count);
  sbi->last_valid_block_count = sbi->total_valid_block_count;
  sbi->reserved_blocks = 0;
+sbi->cur_reserved_blocks = 0;
for (i = 0; i < NR_INODE_TYPE; i++) {
  INIT_LIST_HEAD(&sbi->inode_list[i]);
diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
index a1be

Re: [PATCH v2] f2fs: introduce cur_reserved_blocks in sysfs

2017-08-14 Thread Yunlong Song 

ping...

On 2017/8/11 19:43, Yunlong Song wrote:

In this patch, we add a new sysfs interface, we can use it to gradually achieve
the reserved_blocks finally, even when reserved_blocks is initially set over
user_block_count - total_valid_block_count. This is very useful, especially when
we upgrade kernel with new reserved_blocks value, but old disk image unluckily 
has
user_block_count - total_valid_block_count smaller than the desired 
reserved_blocks.
With this patch, f2fs can try its best to reserve space and get close to the
reserved_blocks, and the current value of achieved reserved_blocks can be shown
in real time.

To ensure there is enough space for supporting system's activation, we safely
increase cur_reserved_blocks in dev_valid_block(,node)_count to only take up the
blocks which are just obsoleted.

Signed-off-by: Yunlong Song 
---
  Documentation/ABI/testing/sysfs-fs-f2fs |  6 ++
  fs/f2fs/f2fs.h  |  9 +++--
  fs/f2fs/super.c |  3 ++-
  fs/f2fs/sysfs.c | 15 ++-
  4 files changed, 25 insertions(+), 8 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs 
b/Documentation/ABI/testing/sysfs-fs-f2fs
index 11b7f4e..bdbb9f3 100644
--- a/Documentation/ABI/testing/sysfs-fs-f2fs
+++ b/Documentation/ABI/testing/sysfs-fs-f2fs
@@ -151,3 +151,9 @@ Date:   August 2017
  Contact:  "Jaegeuk Kim" 
  Description:
 Controls sleep time of GC urgent mode
+
+What:  /sys/fs/f2fs//cur_reserved_blocks
+Date:  August 2017
+Contact:   "Yunlong Song" 
+Description:
+Shows current reserved blocks in system.
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 2f20b6b..62d7343 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1041,6 +1041,7 @@ struct f2fs_sb_info {
block_t discard_blks;   /* discard command candidats */
block_t last_valid_block_count; /* for recovery */
block_t reserved_blocks;/* configurable reserved blocks 
*/
+   block_t cur_reserved_blocks;/* current reserved blocks */
  
  	u32 s_next_generation;			/* for NFS support */
  
@@ -1515,7 +1516,7 @@ static inline int inc_valid_block_count(struct f2fs_sb_info *sbi,
  
  	spin_lock(&sbi->stat_lock);

sbi->total_valid_block_count += (block_t)(*count);
-   avail_user_block_count = sbi->user_block_count - sbi->reserved_blocks;
+   avail_user_block_count = sbi->user_block_count - 
sbi->cur_reserved_blocks;
if (unlikely(sbi->total_valid_block_count > avail_user_block_count)) {
diff = sbi->total_valid_block_count - avail_user_block_count;
*count -= diff;
@@ -1549,6 +1550,8 @@ static inline void dec_valid_block_count(struct 
f2fs_sb_info *sbi,
f2fs_bug_on(sbi, sbi->total_valid_block_count < (block_t) count);
f2fs_bug_on(sbi, inode->i_blocks < sectors);
sbi->total_valid_block_count -= (block_t)count;
+   sbi->cur_reserved_blocks = min(sbi->reserved_blocks,
+   
sbi->cur_reserved_blocks + count);
spin_unlock(&sbi->stat_lock);
f2fs_i_blocks_write(inode, count, false, true);
  }
@@ -1695,7 +1698,7 @@ static inline int inc_valid_node_count(struct 
f2fs_sb_info *sbi,
spin_lock(&sbi->stat_lock);
  
  	valid_block_count = sbi->total_valid_block_count + 1;

-   if (unlikely(valid_block_count + sbi->reserved_blocks >
+   if (unlikely(valid_block_count + sbi->cur_reserved_blocks >
sbi->user_block_count)) {
spin_unlock(&sbi->stat_lock);
goto enospc;
@@ -1738,6 +1741,8 @@ static inline void dec_valid_node_count(struct 
f2fs_sb_info *sbi,
  
  	sbi->total_valid_node_count--;

sbi->total_valid_block_count--;
+   sbi->cur_reserved_blocks = min(sbi->reserved_blocks,
+   
sbi->cur_reserved_blocks + 1);
  
  	spin_unlock(&sbi->stat_lock);
  
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c

index 4c1bdcb..16a805f 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -957,7 +957,7 @@ static int f2fs_statfs(struct dentry *dentry, struct 
kstatfs *buf)
buf->f_blocks = total_count - start_count;
buf->f_bfree = user_block_count - valid_user_blocks(sbi) + ovp_count;
buf->f_bavail = user_block_count - valid_user_blocks(sbi) -
-   sbi->reserved_blocks;
+   sbi->cur_reserved_blocks;
  
  	avail_node_count = sbi->total_node_count - F2FS_RESERVED_NODE_NUM;
  
@@ -2411,6 +2411,7 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)

le64_to_cpu(sbi->ckpt->valid_block_count);
sbi->last_valid_block_count = sbi->total_valid_block_count;

[PATCH v2] f2fs: introduce cur_reserved_blocks in sysfs

2017-08-11 Thread Yunlong Song 
In this patch, we add a new sysfs interface, we can use it to gradually achieve
the reserved_blocks finally, even when reserved_blocks is initially set over
user_block_count - total_valid_block_count. This is very useful, especially when
we upgrade kernel with new reserved_blocks value, but old disk image unluckily 
has
user_block_count - total_valid_block_count smaller than the desired 
reserved_blocks.
With this patch, f2fs can try its best to reserve space and get close to the
reserved_blocks, and the current value of achieved reserved_blocks can be shown
in real time.

To ensure there is enough space for supporting system's activation, we safely
increase cur_reserved_blocks in dev_valid_block(,node)_count to only take up the
blocks which are just obsoleted.

Signed-off-by: Yunlong Song 
---
 Documentation/ABI/testing/sysfs-fs-f2fs |  6 ++
 fs/f2fs/f2fs.h  |  9 +++--
 fs/f2fs/super.c |  3 ++-
 fs/f2fs/sysfs.c | 15 ++-
 4 files changed, 25 insertions(+), 8 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs 
b/Documentation/ABI/testing/sysfs-fs-f2fs
index 11b7f4e..bdbb9f3 100644
--- a/Documentation/ABI/testing/sysfs-fs-f2fs
+++ b/Documentation/ABI/testing/sysfs-fs-f2fs
@@ -151,3 +151,9 @@ Date:   August 2017
 Contact:   "Jaegeuk Kim" 
 Description:
 Controls sleep time of GC urgent mode
+
+What:  /sys/fs/f2fs//cur_reserved_blocks
+Date:  August 2017
+Contact:   "Yunlong Song" 
+Description:
+Shows current reserved blocks in system.
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 2f20b6b..62d7343 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1041,6 +1041,7 @@ struct f2fs_sb_info {
block_t discard_blks;   /* discard command candidats */
block_t last_valid_block_count; /* for recovery */
block_t reserved_blocks;/* configurable reserved blocks 
*/
+   block_t cur_reserved_blocks;/* current reserved blocks */
 
u32 s_next_generation;  /* for NFS support */
 
@@ -1515,7 +1516,7 @@ static inline int inc_valid_block_count(struct 
f2fs_sb_info *sbi,
 
spin_lock(&sbi->stat_lock);
sbi->total_valid_block_count += (block_t)(*count);
-   avail_user_block_count = sbi->user_block_count - sbi->reserved_blocks;
+   avail_user_block_count = sbi->user_block_count - 
sbi->cur_reserved_blocks;
if (unlikely(sbi->total_valid_block_count > avail_user_block_count)) {
diff = sbi->total_valid_block_count - avail_user_block_count;
*count -= diff;
@@ -1549,6 +1550,8 @@ static inline void dec_valid_block_count(struct 
f2fs_sb_info *sbi,
f2fs_bug_on(sbi, sbi->total_valid_block_count < (block_t) count);
f2fs_bug_on(sbi, inode->i_blocks < sectors);
sbi->total_valid_block_count -= (block_t)count;
+   sbi->cur_reserved_blocks = min(sbi->reserved_blocks,
+   
sbi->cur_reserved_blocks + count);
spin_unlock(&sbi->stat_lock);
f2fs_i_blocks_write(inode, count, false, true);
 }
@@ -1695,7 +1698,7 @@ static inline int inc_valid_node_count(struct 
f2fs_sb_info *sbi,
spin_lock(&sbi->stat_lock);
 
valid_block_count = sbi->total_valid_block_count + 1;
-   if (unlikely(valid_block_count + sbi->reserved_blocks >
+   if (unlikely(valid_block_count + sbi->cur_reserved_blocks >
sbi->user_block_count)) {
spin_unlock(&sbi->stat_lock);
goto enospc;
@@ -1738,6 +1741,8 @@ static inline void dec_valid_node_count(struct 
f2fs_sb_info *sbi,
 
sbi->total_valid_node_count--;
sbi->total_valid_block_count--;
+   sbi->cur_reserved_blocks = min(sbi->reserved_blocks,
+   
sbi->cur_reserved_blocks + 1);
 
spin_unlock(&sbi->stat_lock);
 
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 4c1bdcb..16a805f 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -957,7 +957,7 @@ static int f2fs_statfs(struct dentry *dentry, struct 
kstatfs *buf)
buf->f_blocks = total_count - start_count;
buf->f_bfree = user_block_count - valid_user_blocks(sbi) + ovp_count;
buf->f_bavail = user_block_count - valid_user_blocks(sbi) -
-   sbi->reserved_blocks;
+   sbi->cur_reserved_blocks;
 
avail_node_count = sbi->total_node_count - F2FS_RESERVED_NODE_NUM;
 
@@ -2411,6 +2411,7 @@ static int f2fs_fill_super(struct super_block *sb, void 
*data, int silent)
le64_to_cpu(sbi->ckpt->valid_block_count);
sbi->last_valid_block_count = sbi->total_valid_block_count;
sbi->reserved_blocks