scoutfs: add some basic tracepoints

I added these tracepoints to verify that file data isn't reachable after
mount because we're not writing out the inode with the current i_size.

Signed-off-by: Zach Brown <zab@versity.com>

kmod/src/filerw.c

@@ -19,6 +19,7 @@
 #include "inode.h"
 #include "key.h"
 #include "filerw.h"
+#include "scoutfs_trace.h"
 
 /*
  * File data is stored in items just like everything else.  This is very
@@ -167,9 +168,12 @@ static int scoutfs_write_begin(struct file *file, struct address_space *mapping,
 			       loff_t pos, unsigned len, unsigned flags,
 			       struct page **pagep, void **fsdata)
 {
+	struct inode *inode = mapping->host;
 	pgoff_t index = pos >> PAGE_CACHE_SHIFT;
 	struct page *page;
 
+	trace_scoutfs_write_begin(scoutfs_ino(inode), pos, len);
+
 	page = grab_cache_page_write_begin(mapping, index, flags);
 	if (!page)
 		return -ENOMEM;
@@ -185,6 +189,8 @@ static int scoutfs_write_end(struct file *file, struct address_space *mapping,
 	struct inode *inode = mapping->host;
 	unsigned off;
 
+	trace_scoutfs_write_end(scoutfs_ino(inode), pos, len, copied);
+
 	off = pos & (PAGE_CACHE_SIZE - 1);
 
 	/* zero the stale part of the page if we did a short copy */

kmod/src/inode.c

@@ -22,6 +22,7 @@
 #include "segment.h"
 #include "dir.h"
 #include "filerw.h"
+#include "scoutfs_trace.h"
 
 /*
  * XXX
@@ -237,6 +238,7 @@ int scoutfs_dirty_inode_item(struct inode *inode)
 	if (!ret) {
 		store_inode(ref.val, inode);
 		scoutfs_put_ref(&ref);
+		trace_scoutfs_dirty_inode(inode);
 	}
 	return ret;
 }
@@ -264,6 +266,7 @@ void scoutfs_update_inode_item(struct inode *inode)
 
 	store_inode(ref.val, inode);
 	scoutfs_put_ref(&ref);
+	trace_scoutfs_update_inode(inode);
 }
 
 /*

kmod/src/scoutfs_trace.h

@@ -66,10 +66,128 @@ TRACE_EVENT(scoutfs_bloom_miss,
 		  __entry->inode, __entry->type, __entry->offset)
 );
 
+TRACE_EVENT(scoutfs_write_begin,
+	TP_PROTO(u64 ino, loff_t pos, unsigned len),
+
+	TP_ARGS(ino, pos, len),
+
+	TP_STRUCT__entry(
+		__field(__u64, inode)
+		__field(__u64, pos)
+		__field(__u32, len)
+	),
+
+	TP_fast_assign(
+		__entry->inode = ino;
+		__entry->pos = pos;
+		__entry->len = len;
+	),
+
+	TP_printk("ino %llu pos %llu len %u",
+		  __entry->inode, __entry->pos, __entry->len)
+);
+
+TRACE_EVENT(scoutfs_write_end,
+	TP_PROTO(u64 ino, loff_t pos, unsigned len, unsigned copied),
+
+	TP_ARGS(ino, pos, len, copied),
+
+	TP_STRUCT__entry(
+		__field(__u64, inode)
+		__field(__u64, pos)
+		__field(__u32, len)
+		__field(__u32, copied)
+	),
+
+	TP_fast_assign(
+		__entry->inode = ino;
+		__entry->pos = pos;
+		__entry->len = len;
+		__entry->copied = copied;
+	),
+
+	TP_printk("ino %llu pos %llu len %u",
+		  __entry->inode, __entry->pos, __entry->len)
+);
+
+TRACE_EVENT(scoutfs_dirty_inode,
+	TP_PROTO(struct inode *inode),
+
+	TP_ARGS(inode),
+
+	TP_STRUCT__entry(
+		__field(__u64, ino)
+		__field(__u64, size)
+	),
+
+	TP_fast_assign(
+		__entry->ino = scoutfs_ino(inode);
+		__entry->size = inode->i_size;
+	),
+
+	TP_printk("ino %llu size %llu",
+		__entry->ino, __entry->size)
+);
+
+TRACE_EVENT(scoutfs_update_inode,
+	TP_PROTO(struct inode *inode),
+
+	TP_ARGS(inode),
+
+	TP_STRUCT__entry(
+		__field(__u64, ino)
+		__field(__u64, size)
+	),
+
+	TP_fast_assign(
+		__entry->ino = scoutfs_ino(inode);
+		__entry->size = inode->i_size;
+	),
+
+	TP_printk("ino %llu size %llu",
+		__entry->ino, __entry->size)
+);
+
+TRACE_EVENT(scoutfs_dirty_super,
+	TP_PROTO(struct scoutfs_super_block *super),
+
+	TP_ARGS(super),
+
+	TP_STRUCT__entry(
+		__field(__u64, blkno)
+		__field(__u64, seq)
+	),
+
+	TP_fast_assign(
+		__entry->blkno = le64_to_cpu(super->hdr.blkno);
+		__entry->seq = le64_to_cpu(super->hdr.seq);
+	),
+
+	TP_printk("blkno %llu seq %llu",
+		__entry->blkno, __entry->seq)
+);
+
+TRACE_EVENT(scoutfs_write_super,
+	TP_PROTO(struct scoutfs_super_block *super),
+
+	TP_ARGS(super),
+
+	TP_STRUCT__entry(
+		__field(__u64, blkno)
+		__field(__u64, seq)
+	),
+
+	TP_fast_assign(
+		__entry->blkno = le64_to_cpu(super->hdr.blkno);
+		__entry->seq = le64_to_cpu(super->hdr.seq);
+	),
+
+	TP_printk("blkno %llu seq %llu",
+		__entry->blkno, __entry->seq)
+);
 
 #endif /* _TRACE_SCOUTFS_H */
 
-/* This part must be outside protection */
 /* This part must be outside protection */
 #undef TRACE_INCLUDE_PATH
 #define TRACE_INCLUDE_PATH .

kmod/src/super.c

@@ -27,6 +27,7 @@
 #include "manifest.h"
 #include "ring.h"
 #include "segment.h"
+#include "scoutfs_trace.h"
 
 /*
  * We've been dirtying log segment blocks and ring blocks as items were
@@ -71,6 +72,8 @@ int scoutfs_advance_dirty_super(struct super_block *sb)
 
 	le64_add_cpu(&super->hdr.seq, 1);
 
+	trace_scoutfs_dirty_super(super);
+
 	return 0;
 }
 
@@ -96,6 +99,7 @@ int scoutfs_write_dirty_super(struct super_block *sb)
 
 	scoutfs_calc_hdr_crc(bh);
 	mark_buffer_dirty(bh);
+	trace_scoutfs_write_super(super);
 	ret = sync_dirty_buffer(bh);
 	brelse(bh);