f2fs: add a tracepoint for f2fs_write_begin

This patch adds a tracepoint for f2fs_write_begin to trace write op of user.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

2 files changed, 32 insertions, 0 deletions

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index a7bb98f5831a..cde0d69969b9 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -900,6 +900,8 @@ static int f2fs_write_begin(struct file *file, struct address_space *mapping,
         struct dnode_of_data dn;
         int err = 0;
 
+        trace_f2fs_write_begin(inode, pos, len, flags);
+
         f2fs_balance_fs(sbi);
 repeat:
         err = f2fs_convert_inline_data(inode, pos + len);
diff --git a/include/trace/events/f2fs.h b/include/trace/events/f2fs.h
index 67f38faac589..1e9375aa9340 100644
--- a/include/trace/events/f2fs.h
+++ b/include/trace/events/f2fs.h
@@ -659,6 +659,36 @@ DEFINE_EVENT_CONDITION(f2fs__submit_bio, f2fs_submit_read_bio,
         TP_CONDITION(bio)
 );
 
+TRACE_EVENT(f2fs_write_begin,
+
+        TP_PROTO(struct inode *inode, loff_t pos, unsigned int len,
+                                unsigned int flags),
+
+        TP_ARGS(inode, pos, len, flags),
+
+        TP_STRUCT__entry(
+                __field(dev_t,  dev)
+                __field(ino_t,  ino)
+                __field(loff_t, pos)
+                __field(unsigned int, len)
+                __field(unsigned int, flags)
+        ),
+
+        TP_fast_assign(
+                __entry->dev    = inode->i_sb->s_dev;
+                __entry->ino    = inode->i_ino;
+                __entry->pos    = pos;
+                __entry->len    = len;
+                __entry->flags  = flags;
+        ),
+
+        TP_printk("dev = (%d,%d), ino = %lu, pos = %llu, len = %u, flags = %u",
+                show_dev_ino(__entry),
+                (unsigned long long)__entry->pos,
+                __entry->len,
+                __entry->flags)
+);
+
 DECLARE_EVENT_CLASS(f2fs__page,
 
         TP_PROTO(struct page *page, int type),