[PATCH 1/2] vfs: add tracepoints in inode_set_ctime_deleg

[Jeff Layton <jlayton@kernel.org>]

Add tracepoints in inode_set_ctime_deleg() that show the existing ctime,
the requested ctime and the current_time().

Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
 fs/inode.c                       |  5 ++++-
 include/trace/events/timestamp.h | 40 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/fs/inode.c b/fs/inode.c
index 99318b157a9a13b3dd8dad0f5f90951f08ef64de..6a8bf57d649aa0909b85f09e3b5b0fbc81efe303 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -2811,10 +2811,13 @@ struct timespec64 inode_set_ctime_deleg(struct inode *inode, struct timespec64 u
 	cur_ts.tv_sec = inode->i_ctime_sec;
 
 	/* If the update is older than the existing value, skip it. */
-	if (timespec64_compare(&update, &cur_ts) <= 0)
+	if (timespec64_compare(&update, &cur_ts) <= 0) {
+		trace_inode_set_ctime_deleg(inode, &cur_ts, &update, NULL);
 		return cur_ts;
+	}
 
 	ktime_get_coarse_real_ts64_mg(&now);
+	trace_inode_set_ctime_deleg(inode, &cur_ts, &update, &now);
 
 	/* Clamp the update to "now" if it's in the future */
 	if (timespec64_compare(&update, &now) > 0)
diff --git a/include/trace/events/timestamp.h b/include/trace/events/timestamp.h
index c9e5ec930054887a6a7bae8e487611b5ded33d71..e66161d8e14d9b74b0c875f0b324d24895403c18 100644
--- a/include/trace/events/timestamp.h
+++ b/include/trace/events/timestamp.h
@@ -118,6 +118,46 @@ TRACE_EVENT(fill_mg_cmtime,
 		__entry->mtime_s, __entry->mtime_ns
 	)
 );
+
+TRACE_EVENT(inode_set_ctime_deleg,
+	TP_PROTO(struct inode *inode,
+		 struct timespec64 *old,
+		 struct timespec64 *req,
+		 struct timespec64 *now),
+
+	TP_ARGS(inode, old, req, now),
+
+	TP_STRUCT__entry(
+		__field(dev_t,		dev)
+		__field(ino_t,		ino)
+		__field(time64_t,	old_s)
+		__field(time64_t,	req_s)
+		__field(time64_t,	now_s)
+		__field(u32,		old_ns)
+		__field(u32,		req_ns)
+		__field(u32,		now_ns)
+		__field(u32,		gen)
+	),
+
+	TP_fast_assign(
+		__entry->dev		= inode->i_sb->s_dev;
+		__entry->ino		= inode->i_ino;
+		__entry->gen		= inode->i_generation;
+		__entry->old_s		= old->tv_sec;
+		__entry->req_s		= req->tv_sec;
+		__entry->now_s		= now ? now->tv_sec : 0;
+		__entry->old_ns		= old->tv_nsec;
+		__entry->req_ns		= req->tv_nsec;
+		__entry->now_ns		= now ? now->tv_nsec : 0;
+	),
+
+	TP_printk("ino=%d:%d:%ld:%u old=%lld.%u req=%lld.%u now=%lld.%u",
+		MAJOR(__entry->dev), MINOR(__entry->dev), __entry->ino, __entry->gen,
+		__entry->old_s, __entry->old_ns,
+		__entry->req_s, __entry->req_ns,
+		__entry->now_s, __entry->now_ns
+	)
+);
 #endif /* _TRACE_TIMESTAMP_H */
 
 /* This part must be outside protection */

-- 
2.50.1