f2fs: add tracepoints for truncate operation

add tracepoints for tracing the truncate operations
like truncate node/data blocks, f2fs_truncate etc.

Tracepoints are added at entry and exit of operation
to trace the success & failure of operation.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Pankaj Kumar <pankaj.km@samsung.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
[Jaegeuk: combine and modify the tracepoint structures]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

fs/f2fs/file.c

@@ -193,6 +193,9 @@ static int truncate_data_blocks_range(struct dnode_of_data *dn, int count)
 		sync_inode_page(dn);
 	}
 	dn->ofs_in_node = ofs;
+
+	trace_f2fs_truncate_data_blocks_range(dn->inode, dn->nid,
+					 dn->ofs_in_node, nr_free);
 	return nr_free;
 }
 
@@ -229,6 +232,8 @@ static int truncate_blocks(struct inode *inode, u64 from)
 	int count = 0, ilock = -1;
 	int err;
 
+	trace_f2fs_truncate_blocks_enter(inode, from);
+
 	free_from = (pgoff_t)
 			((from + blocksize - 1) >> (sbi->log_blocksize));
 
@@ -239,6 +244,7 @@ static int truncate_blocks(struct inode *inode, u64 from)
 		if (err == -ENOENT)
 			goto free_next;
 		mutex_unlock_op(sbi, ilock);
+		trace_f2fs_truncate_blocks_exit(inode, err);
 		return err;
 	}
 
@@ -263,6 +269,7 @@ free_next:
 	/* lastly zero out the first data page */
 	truncate_partial_data_page(inode, from);
 
+	trace_f2fs_truncate_blocks_exit(inode, err);
 	return err;
 }
 
@@ -272,6 +279,8 @@ void f2fs_truncate(struct inode *inode)
 				S_ISLNK(inode->i_mode)))
 		return;
 
+	trace_f2fs_truncate(inode);
+
 	if (!truncate_blocks(inode, i_size_read(inode))) {
 		inode->i_mtime = inode->i_ctime = CURRENT_TIME;
 		mark_inode_dirty(inode);

fs/f2fs/node.c

@@ -19,6 +19,7 @@
 #include "f2fs.h"
 #include "node.h"
 #include "segment.h"
+#include <trace/events/f2fs.h>
 
 static struct kmem_cache *nat_entry_slab;
 static struct kmem_cache *free_nid_slab;
@@ -508,6 +509,7 @@ invalidate:
 
 	f2fs_put_page(dn->node_page, 1);
 	dn->node_page = NULL;
+	trace_f2fs_truncate_node(dn->inode, dn->nid, ni.blk_addr);
 }
 
 static int truncate_dnode(struct dnode_of_data *dn)
@@ -548,9 +550,13 @@ static int truncate_nodes(struct dnode_of_data *dn, unsigned int nofs,
 	if (dn->nid == 0)
 		return NIDS_PER_BLOCK + 1;
 
+	trace_f2fs_truncate_nodes_enter(dn->inode, dn->nid, dn->data_blkaddr);
+
 	page = get_node_page(sbi, dn->nid);
-	if (IS_ERR(page))
+	if (IS_ERR(page)) {
+		trace_f2fs_truncate_nodes_exit(dn->inode, PTR_ERR(page));
 		return PTR_ERR(page);
+	}
 
 	rn = (struct f2fs_node *)page_address(page);
 	if (depth < 3) {
@@ -592,10 +598,12 @@ static int truncate_nodes(struct dnode_of_data *dn, unsigned int nofs,
 	} else {
 		f2fs_put_page(page, 1);
 	}
+	trace_f2fs_truncate_nodes_exit(dn->inode, freed);
 	return freed;
 
 out_err:
 	f2fs_put_page(page, 1);
+	trace_f2fs_truncate_nodes_exit(dn->inode, ret);
 	return ret;
 }
 
@@ -650,6 +658,9 @@ static int truncate_partial_nodes(struct dnode_of_data *dn,
 fail:
 	for (i = depth - 3; i >= 0; i--)
 		f2fs_put_page(pages[i], 1);
+
+	trace_f2fs_truncate_partial_nodes(dn->inode, nid, depth, err);
+
 	return err;
 }
 
@@ -666,11 +677,15 @@ int truncate_inode_blocks(struct inode *inode, pgoff_t from)
 	struct dnode_of_data dn;
 	struct page *page;
 
+	trace_f2fs_truncate_inode_blocks_enter(inode, from);
+
 	level = get_node_path(from, offset, noffset);
 
 	page = get_node_page(sbi, inode->i_ino);
-	if (IS_ERR(page))
+	if (IS_ERR(page)) {
+		trace_f2fs_truncate_inode_blocks_exit(inode, PTR_ERR(page));
 		return PTR_ERR(page);
+	}
 
 	set_new_dnode(&dn, inode, page, NULL, 0);
 	unlock_page(page);
@@ -740,6 +755,7 @@ skip_partial:
 	}
 fail:
 	f2fs_put_page(page, 0);
+	trace_f2fs_truncate_inode_blocks_exit(inode, err);
 	return err > 0 ? 0 : err;
 }
 

include/trace/events/f2fs.h

@@ -189,6 +189,182 @@ DEFINE_EVENT(f2fs__inode_exit, f2fs_unlink_exit,
 
 	TP_ARGS(inode, ret)
 );
+
+DEFINE_EVENT(f2fs__inode, f2fs_truncate,
+
+	TP_PROTO(struct inode *inode),
+
+	TP_ARGS(inode)
+);
+
+TRACE_EVENT(f2fs_truncate_data_blocks_range,
+
+	TP_PROTO(struct inode *inode, nid_t nid, unsigned int ofs, int free),
+
+	TP_ARGS(inode, nid,  ofs, free),
+
+	TP_STRUCT__entry(
+		__field(dev_t,	dev)
+		__field(ino_t,	ino)
+		__field(nid_t,	nid)
+		__field(unsigned int,	ofs)
+		__field(int,	free)
+	),
+
+	TP_fast_assign(
+		__entry->dev	= inode->i_sb->s_dev;
+		__entry->ino	= inode->i_ino;
+		__entry->nid	= nid;
+		__entry->ofs	= ofs;
+		__entry->free	= free;
+	),
+
+	TP_printk("dev = (%d,%d), ino = %lu, nid = %u, offset = %u, freed = %d",
+		show_dev_ino(__entry),
+		(unsigned int)__entry->nid,
+		__entry->ofs,
+		__entry->free)
+);
+
+DECLARE_EVENT_CLASS(f2fs__truncate_op,
+
+	TP_PROTO(struct inode *inode, u64 from),
+
+	TP_ARGS(inode, from),
+
+	TP_STRUCT__entry(
+		__field(dev_t,	dev)
+		__field(ino_t,	ino)
+		__field(loff_t,	size)
+		__field(blkcnt_t, blocks)
+		__field(u64,	from)
+	),
+
+	TP_fast_assign(
+		__entry->dev	= inode->i_sb->s_dev;
+		__entry->ino	= inode->i_ino;
+		__entry->size	= inode->i_size;
+		__entry->blocks	= inode->i_blocks;
+		__entry->from	= from;
+	),
+
+	TP_printk("dev = (%d,%d), ino = %lu, i_size = %lld, i_blocks = %llu, "
+		"start file offset = %llu",
+		show_dev_ino(__entry),
+		__entry->size,
+		(unsigned long long)__entry->blocks,
+		(unsigned long long)__entry->from)
+);
+
+DEFINE_EVENT(f2fs__truncate_op, f2fs_truncate_blocks_enter,
+
+	TP_PROTO(struct inode *inode, u64 from),
+
+	TP_ARGS(inode, from)
+);
+
+DEFINE_EVENT(f2fs__inode_exit, f2fs_truncate_blocks_exit,
+
+	TP_PROTO(struct inode *inode, int ret),
+
+	TP_ARGS(inode, ret)
+);
+
+DEFINE_EVENT(f2fs__truncate_op, f2fs_truncate_inode_blocks_enter,
+
+	TP_PROTO(struct inode *inode, u64 from),
+
+	TP_ARGS(inode, from)
+);
+
+DEFINE_EVENT(f2fs__inode_exit, f2fs_truncate_inode_blocks_exit,
+
+	TP_PROTO(struct inode *inode, int ret),
+
+	TP_ARGS(inode, ret)
+);
+
+DECLARE_EVENT_CLASS(f2fs__truncate_node,
+
+	TP_PROTO(struct inode *inode, nid_t nid, block_t blk_addr),
+
+	TP_ARGS(inode, nid, blk_addr),
+
+	TP_STRUCT__entry(
+		__field(dev_t,	dev)
+		__field(ino_t,	ino)
+		__field(nid_t,	nid)
+		__field(block_t,	blk_addr)
+	),
+
+	TP_fast_assign(
+		__entry->dev		= inode->i_sb->s_dev;
+		__entry->ino		= inode->i_ino;
+		__entry->nid		= nid;
+		__entry->blk_addr	= blk_addr;
+	),
+
+	TP_printk("dev = (%d,%d), ino = %lu, nid = %u, block_address = 0x%llx",
+		show_dev_ino(__entry),
+		(unsigned int)__entry->nid,
+		(unsigned long long)__entry->blk_addr)
+);
+
+DEFINE_EVENT(f2fs__truncate_node, f2fs_truncate_nodes_enter,
+
+	TP_PROTO(struct inode *inode, nid_t nid, block_t blk_addr),
+
+	TP_ARGS(inode, nid, blk_addr)
+);
+
+DEFINE_EVENT(f2fs__inode_exit, f2fs_truncate_nodes_exit,
+
+	TP_PROTO(struct inode *inode, int ret),
+
+	TP_ARGS(inode, ret)
+);
+
+DEFINE_EVENT(f2fs__truncate_node, f2fs_truncate_node,
+
+	TP_PROTO(struct inode *inode, nid_t nid, block_t blk_addr),
+
+	TP_ARGS(inode, nid, blk_addr)
+);
+
+TRACE_EVENT(f2fs_truncate_partial_nodes,
+
+	TP_PROTO(struct inode *inode, nid_t nid[], int depth, int err),
+
+	TP_ARGS(inode, nid, depth, err),
+
+	TP_STRUCT__entry(
+		__field(dev_t,	dev)
+		__field(ino_t,	ino)
+		__field(nid_t,	nid[3])
+		__field(int,	depth)
+		__field(int,	err)
+	),
+
+	TP_fast_assign(
+		__entry->dev	= inode->i_sb->s_dev;
+		__entry->ino	= inode->i_ino;
+		__entry->nid[0]	= nid[0];
+		__entry->nid[1]	= nid[1];
+		__entry->nid[2]	= nid[2];
+		__entry->depth	= depth;
+		__entry->err	= err;
+	),
+
+	TP_printk("dev = (%d,%d), ino = %lu, "
+		"nid[0] = %u, nid[1] = %u, nid[2] = %u, depth = %d, err = %d",
+		show_dev_ino(__entry),
+		(unsigned int)__entry->nid[0],
+		(unsigned int)__entry->nid[1],
+		(unsigned int)__entry->nid[2],
+		__entry->depth,
+		__entry->err)
+);
+
 #endif /* _TRACE_F2FS_H */
 
  /* This part must be outside protection */