[PATCH RFC 01/10] fs/locks: Add trace_leases_conflict

From: ira . weiny
Date: Wed Jun 05 2019 - 21:49:15 EST


From: Ira Weiny <ira.weiny@xxxxxxxxx>

Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>
---
fs/locks.c | 20 ++++++++++++++-----
include/trace/events/filelock.h | 35 +++++++++++++++++++++++++++++++++
2 files changed, 50 insertions(+), 5 deletions(-)

diff --git a/fs/locks.c b/fs/locks.c
index ec1e4a5df629..0cc2b9f30e22 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1534,11 +1534,21 @@ static void time_out_leases(struct inode *inode, struct list_head *dispose)

static bool leases_conflict(struct file_lock *lease, struct file_lock *breaker)
{
- if ((breaker->fl_flags & FL_LAYOUT) != (lease->fl_flags & FL_LAYOUT))
- return false;
- if ((breaker->fl_flags & FL_DELEG) && (lease->fl_flags & FL_LEASE))
- return false;
- return locks_conflict(breaker, lease);
+ bool rc;
+
+ if ((breaker->fl_flags & FL_LAYOUT) != (lease->fl_flags & FL_LAYOUT)) {
+ rc = false;
+ goto trace;
+ }
+ if ((breaker->fl_flags & FL_DELEG) && (lease->fl_flags & FL_LEASE)) {
+ rc = false;
+ goto trace;
+ }
+
+ rc = locks_conflict(breaker, lease);
+trace:
+ trace_leases_conflict(rc, lease, breaker);
+ return rc;
}

static bool
diff --git a/include/trace/events/filelock.h b/include/trace/events/filelock.h
index fad7befa612d..4b735923f2ff 100644
--- a/include/trace/events/filelock.h
+++ b/include/trace/events/filelock.h
@@ -203,6 +203,41 @@ TRACE_EVENT(generic_add_lease,
show_fl_type(__entry->fl_type))
);

+TRACE_EVENT(leases_conflict,
+ TP_PROTO(bool conflict, struct file_lock *lease, struct file_lock *breaker),
+
+ TP_ARGS(conflict, lease, breaker),
+
+ TP_STRUCT__entry(
+ __field(void *, lease)
+ __field(void *, breaker)
+ __field(unsigned int, l_fl_flags)
+ __field(unsigned int, b_fl_flags)
+ __field(unsigned char, l_fl_type)
+ __field(unsigned char, b_fl_type)
+ __field(bool, conflict)
+ ),
+
+ TP_fast_assign(
+ __entry->lease = lease;
+ __entry->l_fl_flags = lease->fl_flags;
+ __entry->l_fl_type = lease->fl_type;
+ __entry->breaker = breaker;
+ __entry->b_fl_flags = breaker->fl_flags;
+ __entry->b_fl_type = breaker->fl_type;
+ __entry->conflict = conflict;
+ ),
+
+ TP_printk("conflict %d: lease=0x%p fl_flags=%s fl_type=%s; breaker=0x%p fl_flags=%s fl_type=%s",
+ __entry->conflict,
+ __entry->lease,
+ show_fl_flags(__entry->l_fl_flags),
+ show_fl_type(__entry->l_fl_type),
+ __entry->breaker,
+ show_fl_flags(__entry->b_fl_flags),
+ show_fl_type(__entry->b_fl_type))
+);
+
#endif /* _TRACE_FILELOCK_H */

/* This part must be outside protection */
--
2.20.1