f2fs: add tracepoints for sync & inode operations

Add tracepoints in f2fs for tracing the syncing
operations like filesystem sync, file sync enter/exit.
It will helf to trace the code under debugging scenarios.

Also add tracepoints for tracing the various inode operations
like building inode, eviction of inode, link/unlike of
inodes.

Signed-off-by: Namjae Jeon <[e-mail]>
Signed-off-by: Pankaj Kumar <[e-mail]>
Acked-by: Steven Rostedt <[e-mail]>
[Jaegeuk: combine and modify the tracepoint structures]
Signed-off-by: Jaegeuk Kim <[e-mail]>

fs/f2fs/file.c

···
 #include "segment.h"
 #include "xattr.h"
 #include "acl.h"
+#include <trace/events/f2fs.h>
 
 static int f2fs_vm_page_mkwrite(struct vm_area_struct *vma,
 						struct vm_fault *vmf)
···
 	if (inode->i_sb->s_flags & MS_RDONLY)
 		return 0;
 
+	trace_f2fs_sync_file_enter(inode);
 	ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
-	if (ret)
+	if (ret) {
+		trace_f2fs_sync_file_exit(inode, need_cp, datasync, ret);
 		return ret;
+	}
 
 	/* guarantee free sections for fsync */
 	f2fs_balance_fs(sbi);
···
 	}
 out:
 	mutex_unlock(&inode->i_mutex);
+	trace_f2fs_sync_file_exit(inode, need_cp, datasync, ret);
 	return ret;
 }
 

fs/f2fs/inode.c

···
 #include "f2fs.h"
 #include "node.h"
 
+#include <trace/events/f2fs.h>
+
 void f2fs_set_inode_flags(struct inode *inode)
 {
 	unsigned int flags = F2FS_I(inode)->i_flags;
···
 {
 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
 	struct inode *inode;
-	int ret;
+	int ret = 0;
 
 	inode = iget_locked(sb, ino);
 	if (!inode)
 		return ERR_PTR(-ENOMEM);
-	if (!(inode->i_state & I_NEW))
+
+	if (!(inode->i_state & I_NEW)) {
+		trace_f2fs_iget(inode);
 		return inode;
+	}
 	if (ino == F2FS_NODE_INO(sbi) || ino == F2FS_META_INO(sbi))
 		goto make_now;
 
···
 		goto bad_inode;
 	}
 	unlock_new_inode(inode);
-
+	trace_f2fs_iget(inode);
 	return inode;
 
 bad_inode:
 	iget_failed(inode);
+	trace_f2fs_iget_exit(inode, ret);
 	return ERR_PTR(ret);
 }
 
···
 	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
 	int ilock;
 
+	trace_f2fs_evict_inode(inode);
 	truncate_inode_pages(&inode->i_data, 0);
 
 	if (inode->i_ino == F2FS_NODE_INO(sbi) ||

fs/f2fs/namei.c

···
 #include "node.h"
 #include "xattr.h"
 #include "acl.h"
+#include <trace/events/f2fs.h>
 
 static struct inode *f2fs_new_inode(struct inode *dir, umode_t mode)
 {
···
 	int err = -ENOENT;
 	int ilock;
 
+	trace_f2fs_unlink_enter(dir, dentry);
 	f2fs_balance_fs(sbi);
 
 	de = f2fs_find_entry(dir, &dentry->d_name, &page);
···
 	/* In order to evict this inode,  we set it dirty */
 	mark_inode_dirty(inode);
 fail:
+	trace_f2fs_unlink_exit(inode, err);
 	return err;
 }
 

fs/f2fs/super.c

···
 #include "segment.h"
 #include "xattr.h"
 
+#define CREATE_TRACE_POINTS
+#include <trace/events/f2fs.h>
+
 static struct kmem_cache *f2fs_inode_cachep;
 
 enum {
···
 int f2fs_sync_fs(struct super_block *sb, int sync)
 {
 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
+
+	trace_f2fs_sync_fs(sb, sync);
 
 	if (!sbi->s_dirty && !get_pages(sbi, F2FS_DIRTY_NODES))
 		return 0;

include/trace/events/f2fs.h

···
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM f2fs
+
+#if !defined(_TRACE_F2FS_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_F2FS_H
+
+#include <linux/tracepoint.h>
+
+#define show_dev(entry)		MAJOR(entry->dev), MINOR(entry->dev)
+#define show_dev_ino(entry)	show_dev(entry), (unsigned long)entry->ino
+
+DECLARE_EVENT_CLASS(f2fs__inode,
+
+	TP_PROTO(struct inode *inode),
+
+	TP_ARGS(inode),
+
+	TP_STRUCT__entry(
+		__field(dev_t,	dev)
+		__field(ino_t,	ino)
+		__field(ino_t,	pino)
+		__field(umode_t, mode)
+		__field(loff_t,	size)
+		__field(unsigned int, nlink)
+		__field(blkcnt_t, blocks)
+		__field(__u8,	advise)
+	),
+
+	TP_fast_assign(
+		__entry->dev	= inode->i_sb->s_dev;
+		__entry->ino	= inode->i_ino;
+		__entry->pino	= F2FS_I(inode)->i_pino;
+		__entry->mode	= inode->i_mode;
+		__entry->nlink	= inode->i_nlink;
+		__entry->size	= inode->i_size;
+		__entry->blocks	= inode->i_blocks;
+		__entry->advise	= F2FS_I(inode)->i_advise;
+	),
+
+	TP_printk("dev = (%d,%d), ino = %lu, pino = %lu, i_mode = 0x%hx, "
+		"i_size = %lld, i_nlink = %u, i_blocks = %llu, i_advise = 0x%x",
+		show_dev_ino(__entry),
+		(unsigned long)__entry->pino,
+		__entry->mode,
+		__entry->size,
+		(unsigned int)__entry->nlink,
+		(unsigned long long)__entry->blocks,
+		(unsigned char)__entry->advise)
+);
+
+DECLARE_EVENT_CLASS(f2fs__inode_exit,
+
+	TP_PROTO(struct inode *inode, int ret),
+
+	TP_ARGS(inode, ret),
+
+	TP_STRUCT__entry(
+		__field(dev_t,	dev)
+		__field(ino_t,	ino)
+		__field(int,	ret)
+	),
+
+	TP_fast_assign(
+		__entry->dev	= inode->i_sb->s_dev;
+		__entry->ino	= inode->i_ino;
+		__entry->ret	= ret;
+	),
+
+	TP_printk("dev = (%d,%d), ino = %lu, ret = %d",
+		show_dev_ino(__entry),
+		__entry->ret)
+);
+
+DEFINE_EVENT(f2fs__inode, f2fs_sync_file_enter,
+
+	TP_PROTO(struct inode *inode),
+
+	TP_ARGS(inode)
+);
+
+TRACE_EVENT(f2fs_sync_file_exit,
+
+	TP_PROTO(struct inode *inode, bool need_cp, int datasync, int ret),
+
+	TP_ARGS(inode, need_cp, datasync, ret),
+
+	TP_STRUCT__entry(
+		__field(dev_t,	dev)
+		__field(ino_t,	ino)
+		__field(bool,	need_cp)
+		__field(int,	datasync)
+		__field(int,	ret)
+	),
+
+	TP_fast_assign(
+		__entry->dev		= inode->i_sb->s_dev;
+		__entry->ino		= inode->i_ino;
+		__entry->need_cp	= need_cp;
+		__entry->datasync	= datasync;
+		__entry->ret		= ret;
+	),
+
+	TP_printk("dev = (%d,%d), ino = %lu, checkpoint is %s, "
+		"datasync = %d, ret = %d",
+		show_dev_ino(__entry),
+		__entry->need_cp ? "needed" : "not needed",
+		__entry->datasync,
+		__entry->ret)
+);
+
+TRACE_EVENT(f2fs_sync_fs,
+
+	TP_PROTO(struct super_block *sb, int wait),
+
+	TP_ARGS(sb, wait),
+
+	TP_STRUCT__entry(
+		__field(dev_t,	dev)
+		__field(int,	dirty)
+		__field(int,	wait)
+	),
+
+	TP_fast_assign(
+		__entry->dev	= sb->s_dev;
+		__entry->dirty	= F2FS_SB(sb)->s_dirty;
+		__entry->wait	= wait;
+	),
+
+	TP_printk("dev = (%d,%d), superblock is %s, wait = %d",
+		show_dev(__entry),
+		__entry->dirty ? "dirty" : "not dirty",
+		__entry->wait)
+);
+
+DEFINE_EVENT(f2fs__inode, f2fs_iget,
+
+	TP_PROTO(struct inode *inode),
+
+	TP_ARGS(inode)
+);
+
+DEFINE_EVENT(f2fs__inode_exit, f2fs_iget_exit,
+
+	TP_PROTO(struct inode *inode, int ret),
+
+	TP_ARGS(inode, ret)
+);
+
+DEFINE_EVENT(f2fs__inode, f2fs_evict_inode,
+
+	TP_PROTO(struct inode *inode),
+
+	TP_ARGS(inode)
+);
+
+TRACE_EVENT(f2fs_unlink_enter,
+
+	TP_PROTO(struct inode *dir, struct dentry *dentry),
+
+	TP_ARGS(dir, dentry),
+
+	TP_STRUCT__entry(
+		__field(dev_t,	dev)
+		__field(ino_t,	ino)
+		__field(loff_t,	size)
+		__field(blkcnt_t, blocks)
+		__field(const char *,	name)
+	),
+
+	TP_fast_assign(
+		__entry->dev	= dir->i_sb->s_dev;
+		__entry->ino	= dir->i_ino;
+		__entry->size	= dir->i_size;
+		__entry->blocks	= dir->i_blocks;
+		__entry->name	= dentry->d_name.name;
+	),
+
+	TP_printk("dev = (%d,%d), dir ino = %lu, i_size = %lld, "
+		"i_blocks = %llu, name = %s",
+		show_dev_ino(__entry),
+		__entry->size,
+		(unsigned long long)__entry->blocks,
+		__entry->name)
+);
+
+DEFINE_EVENT(f2fs__inode_exit, f2fs_unlink_exit,
+
+	TP_PROTO(struct inode *inode, int ret),
+
+	TP_ARGS(inode, ret)
+);
+#endif /* _TRACE_F2FS_H */
+
+ /* This part must be outside protection */
+#include <trace/define_trace.h>