f2fs: add app/fs io stat

This patch enables inner app/fs io stats and introduces below virtual fs
nodes for exposing stats info:
/sys/fs/f2fs/<dev>/iostat_enable
/proc/fs/f2fs/<dev>/iostat_info

Signed-off-by: Chao Yu <yuchao0@huawei.com>
[Jaegeuk Kim: fix wrong stat assignment]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

1 files changed, 56 insertions, 3 deletions

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 7c1244ba92a8..0ccccbfdeeab 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -557,6 +557,7 @@ struct f2fs_inode_info {
 	f2fs_hash_t chash;		/* hash value of given file name */
 	unsigned int clevel;		/* maximum level of given file name */
 	struct task_struct *task;	/* lookup and create consistency */
+	struct task_struct *cp_task;	/* separate cp/wb IO stats*/
 	nid_t i_xattr_nid;		/* node id that contains xattrs */
 	loff_t	last_disk_size;		/* lastly written file size */
 
@@ -863,6 +864,23 @@ enum need_lock_type {
 	LOCK_RETRY,
 };
 
+enum iostat_type {
+	APP_DIRECT_IO,			/* app direct IOs */
+	APP_BUFFERED_IO,		/* app buffered IOs */
+	APP_WRITE_IO,			/* app write IOs */
+	APP_MAPPED_IO,			/* app mapped IOs */
+	FS_DATA_IO,			/* data IOs from kworker/fsync/reclaimer */
+	FS_NODE_IO,			/* node IOs from kworker/fsync/reclaimer */
+	FS_META_IO,			/* meta IOs from kworker/reclaimer */
+	FS_GC_DATA_IO,			/* data IOs from forground gc */
+	FS_GC_NODE_IO,			/* node IOs from forground gc */
+	FS_CP_DATA_IO,			/* data IOs from checkpoint */
+	FS_CP_NODE_IO,			/* node IOs from checkpoint */
+	FS_CP_META_IO,			/* meta IOs from checkpoint */
+	FS_DISCARD,			/* discard */
+	NR_IO_TYPE,
+};
+
 struct f2fs_io_info {
 	struct f2fs_sb_info *sbi;	/* f2fs_sb_info pointer */
 	enum page_type type;	/* contains DATA/NODE/META/META_FLUSH */
@@ -877,6 +895,7 @@ struct f2fs_io_info {
 	bool submitted;		/* indicate IO submission */
 	int need_lock;		/* indicate we need to lock cp_rwsem */
 	bool in_list;		/* indicate fio is in io_list */
+	enum iostat_type io_type;	/* io type */
 };
 
 #define is_read_io(rw) ((rw) == READ)
@@ -1068,6 +1087,11 @@ struct f2fs_sb_info {
 #endif
 	spinlock_t stat_lock;			/* lock for stat operations */
 
+	/* For app/fs IO statistics */
+	spinlock_t iostat_lock;
+	unsigned long long write_iostat[NR_IO_TYPE];
+	bool iostat_enable;
+
 	/* For sysfs suppport */
 	struct kobject s_kobj;
 	struct completion s_kobj_unregister;
@@ -2291,6 +2315,31 @@ static inline int get_extra_isize(struct inode *inode)
 		sizeof((f2fs_inode)->field))			\
 		<= (F2FS_OLD_ATTRIBUTE_SIZE + extra_isize))	\
 
+static inline void f2fs_reset_iostat(struct f2fs_sb_info *sbi)
+{
+	int i;
+
+	spin_lock(&sbi->iostat_lock);
+	for (i = 0; i < NR_IO_TYPE; i++)
+		sbi->write_iostat[i] = 0;
+	spin_unlock(&sbi->iostat_lock);
+}
+
+static inline void f2fs_update_iostat(struct f2fs_sb_info *sbi,
+			enum iostat_type type, unsigned long long io_bytes)
+{
+	if (!sbi->iostat_enable)
+		return;
+	spin_lock(&sbi->iostat_lock);
+	sbi->write_iostat[type] += io_bytes;
+
+	if (type == APP_WRITE_IO || type == APP_DIRECT_IO)
+		sbi->write_iostat[APP_BUFFERED_IO] =
+			sbi->write_iostat[APP_WRITE_IO] -
+			sbi->write_iostat[APP_DIRECT_IO];
+	spin_unlock(&sbi->iostat_lock);
+}
+
 /*
  * file.c
  */
@@ -2418,7 +2467,7 @@ void move_node_page(struct page *node_page, int gc_type);
 int fsync_node_pages(struct f2fs_sb_info *sbi, struct inode *inode,
 			struct writeback_control *wbc, bool atomic);
 int sync_node_pages(struct f2fs_sb_info *sbi, struct writeback_control *wbc,
-			bool do_balance);
+			bool do_balance, enum iostat_type io_type);
 void build_free_nids(struct f2fs_sb_info *sbi, bool sync, bool mount);
 bool alloc_nid(struct f2fs_sb_info *sbi, nid_t *nid);
 void alloc_nid_done(struct f2fs_sb_info *sbi, nid_t nid);
@@ -2461,7 +2510,8 @@ int f2fs_trim_fs(struct f2fs_sb_info *sbi, struct fstrim_range *range);
 bool exist_trim_candidates(struct f2fs_sb_info *sbi, struct cp_control *cpc);
 struct page *get_sum_page(struct f2fs_sb_info *sbi, unsigned int segno);
 void update_meta_page(struct f2fs_sb_info *sbi, void *src, block_t blk_addr);
-void write_meta_page(struct f2fs_sb_info *sbi, struct page *page);
+void write_meta_page(struct f2fs_sb_info *sbi, struct page *page,
+						enum iostat_type io_type);
 void write_node_page(unsigned int nid, struct f2fs_io_info *fio);
 void write_data_page(struct dnode_of_data *dn, struct f2fs_io_info *fio);
 int rewrite_data_page(struct f2fs_io_info *fio);
@@ -2502,7 +2552,7 @@ int ra_meta_pages(struct f2fs_sb_info *sbi, block_t start, int nrpages,
 			int type, bool sync);
 void ra_meta_pages_cond(struct f2fs_sb_info *sbi, pgoff_t index);
 long sync_meta_pages(struct f2fs_sb_info *sbi, enum page_type type,
-			long nr_to_write);
+			long nr_to_write, enum iostat_type io_type);
 void add_ino_entry(struct f2fs_sb_info *sbi, nid_t ino, int type);
 void remove_ino_entry(struct f2fs_sb_info *sbi, nid_t ino, int type);
 void release_ino_entry(struct f2fs_sb_info *sbi, bool all);
@@ -2555,6 +2605,9 @@ int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map,
 int f2fs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 			u64 start, u64 len);
 void f2fs_set_page_dirty_nobuffers(struct page *page);
+int __f2fs_write_data_pages(struct address_space *mapping,
+						struct writeback_control *wbc,
+						enum iostat_type io_type);
 void f2fs_invalidate_page(struct page *page, unsigned int offset,
 			unsigned int length);
 int f2fs_release_page(struct page *page, gfp_t wait);