[PATCH 2/2] f2fs: use ioprio hint for hot and pinned files

[Daniel Lee <chullee@google.com>]

Apply the `ioprio_hint` to set `F2FS_IOPRIO_WRITE` priority
on files identified as "hot" at creation and on files that are
pinned via ioctl.

Signed-off-by: Daniel Lee <chullee@google.com>
---
 fs/f2fs/f2fs.h  | 21 +++++++++++++++++++++
 fs/f2fs/file.c  |  3 +++
 fs/f2fs/namei.c | 11 +++++++----
 3 files changed, 31 insertions(+), 4 deletions(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 162d79a3c1a5..0b05b3b6386b 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -3441,6 +3441,27 @@ static inline void set_file(struct inode *inode, int type)
 	f2fs_mark_inode_dirty_sync(inode, true);
 }
 
+static inline int get_ioprio(struct inode *inode)
+{
+	return F2FS_I(inode)->ioprio_hint;
+}
+
+static inline void set_ioprio(struct inode *inode, int level)
+{
+	if (get_ioprio(inode) == level)
+		return;
+	F2FS_I(inode)->ioprio_hint = level;
+	f2fs_mark_inode_dirty_sync(inode, true);
+}
+
+static inline void clear_ioprio(struct inode *inode)
+{
+	if (get_ioprio(inode) == 0)
+		return;
+	F2FS_I(inode)->ioprio_hint = 0;
+	f2fs_mark_inode_dirty_sync(inode, true);
+}
+
 static inline void clear_file(struct inode *inode, int type)
 {
 	if (!is_file(inode, type))
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 4fd45e94661a..95a3b4b59dd1 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -3496,6 +3496,7 @@ static int f2fs_ioc_set_pin_file(struct file *filp, unsigned long arg)
 
 	if (!pin) {
 		clear_inode_flag(inode, FI_PIN_FILE);
+		clear_ioprio(inode);
 		f2fs_i_gc_failures_write(inode, 0);
 		goto done;
 	} else if (f2fs_is_pinned_file(inode)) {
@@ -3529,6 +3530,8 @@ static int f2fs_ioc_set_pin_file(struct file *filp, unsigned long arg)
 	}
 
 	set_inode_flag(inode, FI_PIN_FILE);
+	file_set_hot(inode);
+	set_ioprio(inode, F2FS_IOPRIO_WRITE);
 	ret = F2FS_I(inode)->i_gc_failures;
 done:
 	f2fs_update_time(sbi, REQ_TIME);
diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
index 07e333ee21b7..0f96a0b86c40 100644
--- a/fs/f2fs/namei.c
+++ b/fs/f2fs/namei.c
@@ -191,9 +191,10 @@ static void set_compress_new_inode(struct f2fs_sb_info *sbi, struct inode *dir,
 }
 
 /*
- * Set file's temperature for hot/cold data separation
+ * Set file's temperature (for hot/cold data separation) and
+ * I/O priority, based on filename extension
  */
-static void set_file_temperature(struct f2fs_sb_info *sbi, struct inode *inode,
+static void set_file_temp_prio(struct f2fs_sb_info *sbi, struct inode *inode,
 		const unsigned char *name)
 {
 	__u8 (*extlist)[F2FS_EXTENSION_LEN] = sbi->raw_super->extension_list;
@@ -212,8 +213,10 @@ static void set_file_temperature(struct f2fs_sb_info *sbi, struct inode *inode,
 
 	if (i < cold_count)
 		file_set_cold(inode);
-	else
+	else {
 		file_set_hot(inode);
+		set_ioprio(inode, F2FS_IOPRIO_WRITE);
+	}
 }
 
 static struct inode *f2fs_new_inode(struct mnt_idmap *idmap,
@@ -317,7 +320,7 @@ static struct inode *f2fs_new_inode(struct mnt_idmap *idmap,
 		set_inode_flag(inode, FI_INLINE_DATA);
 
 	if (name && !test_opt(sbi, DISABLE_EXT_IDENTIFY))
-		set_file_temperature(sbi, inode, name);
+		set_file_temp_prio(sbi, inode, name);
 
 	stat_inc_inline_xattr(inode);
 	stat_inc_inline_inode(inode);
-- 
2.50.0.rc1.591.g9c95f17f64-goog