2015-07-15 09:30:37

by Chao Yu

[permalink] [raw]
Subject: [PATCH 2/2] f2fs: use atomic_t to record hit ratio info of extent cache

Variables for recording extent cache ratio info were updated without
protection, this patch tries to alter them to atomic_t type for more
accurate stat.

Signed-off-by: Chao Yu <[email protected]>
---
fs/f2fs/debug.c | 7 +++++--
fs/f2fs/extent_cache.c | 6 +++---
fs/f2fs/f2fs.h | 7 ++++---
3 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/fs/f2fs/debug.c b/fs/f2fs/debug.c
index 2aeaf4e..bc215fd 100644
--- a/fs/f2fs/debug.c
+++ b/fs/f2fs/debug.c
@@ -33,8 +33,8 @@ static void update_general_status(struct f2fs_sb_info *sbi)
int i;

/* validation check of the segment numbers */
- si->hit_ext = sbi->read_hit_ext;
- si->total_ext = sbi->total_hit_ext;
+ si->hit_ext = atomic_read(&sbi->read_hit_ext);
+ si->total_ext = atomic_read(&sbi->total_hit_ext);
si->ext_tree = sbi->total_ext_tree;
si->ext_node = atomic_read(&sbi->total_ext_node);
si->ndirty_node = get_pages(sbi, F2FS_DIRTY_NODES);
@@ -369,6 +369,9 @@ int f2fs_build_stats(struct f2fs_sb_info *sbi)
si->sbi = sbi;
sbi->stat_info = si;

+ atomic_set(&sbi->total_hit_ext, 0);
+ atomic_set(&sbi->read_hit_ext, 0);
+
atomic_set(&sbi->inline_xattr, 0);
atomic_set(&sbi->inline_inode, 0);
atomic_set(&sbi->inline_dir, 0);
diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c
index 5f78fc1..362df8c 100644
--- a/fs/f2fs/extent_cache.c
+++ b/fs/f2fs/extent_cache.c
@@ -279,7 +279,7 @@ static bool f2fs_lookup_extent_tree(struct inode *inode, pgoff_t pgofs,
et->largest.fofs + et->largest.len > pgofs) {
*ei = et->largest;
ret = true;
- stat_inc_read_hit(sbi->sb);
+ stat_inc_read_hit(sbi);
goto out;
}

@@ -292,10 +292,10 @@ static bool f2fs_lookup_extent_tree(struct inode *inode, pgoff_t pgofs,
et->cached_en = en;
spin_unlock(&sbi->extent_lock);
ret = true;
- stat_inc_read_hit(sbi->sb);
+ stat_inc_read_hit(sbi);
}
out:
- stat_inc_total_hit(sbi->sb);
+ stat_inc_total_hit(sbi);
read_unlock(&et->lock);

trace_f2fs_lookup_extent_tree_end(inode, pgofs, ei);
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index b18b852..38ba525 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -781,7 +781,8 @@ struct f2fs_sb_info {
unsigned int segment_count[2]; /* # of allocated segments */
unsigned int block_count[2]; /* # of allocated blocks */
atomic_t inplace_count; /* # of inplace update */
- int total_hit_ext, read_hit_ext; /* extent cache hit ratio */
+ atomic_t total_hit_ext; /* # of lookup extent cache */
+ atomic_t read_hit_ext; /* # of hit extent cache */
atomic_t inline_xattr; /* # of inline_xattr inodes */
atomic_t inline_inode; /* # of inline_data inodes */
atomic_t inline_dir; /* # of inline_dentry inodes */
@@ -1837,8 +1838,8 @@ static inline struct f2fs_stat_info *F2FS_STAT(struct f2fs_sb_info *sbi)
#define stat_inc_bggc_count(sbi) ((sbi)->bg_gc++)
#define stat_inc_dirty_dir(sbi) ((sbi)->n_dirty_dirs++)
#define stat_dec_dirty_dir(sbi) ((sbi)->n_dirty_dirs--)
-#define stat_inc_total_hit(sb) ((F2FS_SB(sb))->total_hit_ext++)
-#define stat_inc_read_hit(sb) ((F2FS_SB(sb))->read_hit_ext++)
+#define stat_inc_total_hit(sbi) (atomic_inc(&(sbi)->total_hit_ext))
+#define stat_inc_read_hit(sbi) (atomic_inc(&(sbi)->read_hit_ext))
#define stat_inc_inline_xattr(inode) \
do { \
if (f2fs_has_inline_xattr(inode)) \
--
2.4.2