[PATCH 4/5] f2fs: use percpu_counter for alloc_valid_block_count

[Jaegeuk Kim <jaegeuk@kernel.org>]

This patch uses percpu_count for sbi->alloc_valid_block_count.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
---
 fs/f2fs/checkpoint.c | 2 +-
 fs/f2fs/f2fs.h       | 8 +++++---
 fs/f2fs/recovery.c   | 5 +++--
 fs/f2fs/super.c      | 7 +++++--
 4 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index d04113b..140643d 100644
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -1079,7 +1079,7 @@ static int do_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
 
 	/* update user_block_counts */
 	sbi->last_valid_block_count = sbi->total_valid_block_count;
-	sbi->alloc_valid_block_count = 0;
+	percpu_counter_set(&sbi->alloc_valid_block_count, 0);
 
 	/* Here, we only have one bio having CP pack */
 	sync_meta_pages(sbi, META_FLUSH, LONG_MAX);
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index ae978a1..43aa692 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -829,13 +829,14 @@ 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 */
 
 	/* # of pages, see count_type */
 	struct percpu_counter nr_pages[NR_COUNT_TYPE];
+	/* # of allocated blocks */
+	struct percpu_counter alloc_valid_block_count;
 
 	struct f2fs_mount_info mount_opt;	/* mount options */
 
@@ -1161,8 +1162,9 @@ static inline bool inc_valid_block_count(struct f2fs_sb_info *sbi,
 	inode->i_blocks += *count;
 	sbi->total_valid_block_count =
 		sbi->total_valid_block_count + (block_t)(*count);
-	sbi->alloc_valid_block_count += (block_t)(*count);
 	spin_unlock(&sbi->stat_lock);
+
+	percpu_counter_add(&sbi->alloc_valid_block_count, (*count));
 	return true;
 }
 
@@ -1310,11 +1312,11 @@ static inline bool inc_valid_node_count(struct f2fs_sb_info *sbi,
 	if (inode)
 		inode->i_blocks++;
 
-	sbi->alloc_valid_block_count++;
 	sbi->total_valid_node_count++;
 	sbi->total_valid_block_count++;
 	spin_unlock(&sbi->stat_lock);
 
+	percpu_counter_inc(&sbi->alloc_valid_block_count);
 	return true;
 }
 
diff --git a/fs/f2fs/recovery.c b/fs/f2fs/recovery.c
index 6303b2a..f89b70e 100644
--- a/fs/f2fs/recovery.c
+++ b/fs/f2fs/recovery.c
@@ -49,8 +49,9 @@ static struct kmem_cache *fsync_entry_slab;
 
 bool space_for_roll_forward(struct f2fs_sb_info *sbi)
 {
-	if (sbi->last_valid_block_count + sbi->alloc_valid_block_count
-			> sbi->user_block_count)
+	s64 nalloc = percpu_counter_sum_positive(&sbi->alloc_valid_block_count);
+
+	if (sbi->last_valid_block_count + nalloc > sbi->user_block_count)
 		return false;
 	return true;
 }
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 56f177b..c0fd075 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -618,6 +618,7 @@ static void destroy_percpu_info(struct f2fs_sb_info *sbi)
 
 	for (i = 0; i < NR_COUNT_TYPE; i++)
 		percpu_counter_destroy(&sbi->nr_pages[i]);
+	percpu_counter_destroy(&sbi->alloc_valid_block_count);
 }
 
 static void f2fs_put_super(struct super_block *sb)
@@ -1384,7 +1385,9 @@ static int init_percpu_info(struct f2fs_sb_info *sbi)
 		if (err)
 			return err;
 	}
-	return 0;
+
+	return percpu_counter_init(&sbi->alloc_valid_block_count, 0,
+								GFP_KERNEL);
 }
 
 /*
@@ -1603,7 +1606,7 @@ try_onemore:
 	sbi->total_valid_block_count =
 				le64_to_cpu(sbi->ckpt->valid_block_count);
 	sbi->last_valid_block_count = sbi->total_valid_block_count;
-	sbi->alloc_valid_block_count = 0;
+
 	for (i = 0; i < NR_INODE_TYPE; i++) {
 		INIT_LIST_HEAD(&sbi->inode_list[i]);
 		spin_lock_init(&sbi->inode_lock[i]);
-- 
2.6.3