[PATCH v2 05/28] fsnotify: new tracepoint in fsnotify()

[Jeff Layton]

Add a tracepoint so we can see exactly how this is being called.

Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
---
 fs/notify/fsnotify.c            |  5 ++++
 include/trace/events/fsnotify.h | 51 +++++++++++++++++++++++++++++++++++++++++
 include/trace/misc/fsnotify.h   | 35 ++++++++++++++++++++++++++++
 3 files changed, 91 insertions(+)

diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c
index 9995de1710e5..5448738635f6 100644
--- a/fs/notify/fsnotify.c
+++ b/fs/notify/fsnotify.c
@@ -14,6 +14,9 @@
 #include <linux/fsnotify_backend.h>
 #include "fsnotify.h"
 
+#define CREATE_TRACE_POINTS
+#include <trace/events/fsnotify.h>
+
 /*
  * Clear all of the marks on an inode when it is being evicted from core
  */
@@ -504,6 +507,8 @@ int fsnotify(__u32 mask, const void *data, int data_type, struct inode *dir,
 	int ret = 0;
 	__u32 test_mask, marks_mask = 0;
 
+	trace_fsnotify(mask, data, data_type, dir, file_name, inode, cookie);
+
 	if (path)
 		mnt = real_mount(path->mnt);
 
diff --git a/include/trace/events/fsnotify.h b/include/trace/events/fsnotify.h
new file mode 100644
index 000000000000..341bbd57a39b
--- /dev/null
+++ b/include/trace/events/fsnotify.h
@@ -0,0 +1,51 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM fsnotify
+
+#if !defined(_TRACE_FSNOTIFY_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_FSNOTIFY_H
+
+#include <linux/tracepoint.h>
+
+#include <trace/misc/fsnotify.h>
+
+TRACE_EVENT(fsnotify,
+	TP_PROTO(__u32 mask, const void *data, int data_type,
+		 struct inode *dir, const struct qstr *file_name,
+		 struct inode *inode, u32 cookie),
+
+	TP_ARGS(mask, data, data_type, dir, file_name, inode, cookie),
+
+	TP_STRUCT__entry(
+		__field(__u32, mask)
+		__field(unsigned long, dir_ino)
+		__field(unsigned long, ino)
+		__field(dev_t, s_dev)
+		__field(int, data_type)
+		__field(u32, cookie)
+		__string(file_name, file_name ? (const char *)file_name->name : "")
+	),
+
+	TP_fast_assign(
+		__entry->mask = mask;
+		__entry->dir_ino = dir ? dir->i_ino : 0;
+		__entry->ino = inode ? inode->i_ino : 0;
+		__entry->s_dev = dir ? dir->i_sb->s_dev :
+				 inode ? inode->i_sb->s_dev : 0;
+		__entry->data_type = data_type;
+		__entry->cookie = cookie;
+		__assign_str(file_name);
+	),
+
+	TP_printk("dev=%d:%d dir=%lu ino=%lu data_type=%d cookie=0x%x mask=0x%x %s name=%s",
+		  MAJOR(__entry->s_dev), MINOR(__entry->s_dev),
+		  __entry->dir_ino, __entry->ino,
+		  __entry->data_type, __entry->cookie,
+		  __entry->mask, show_fsnotify_mask(__entry->mask),
+		  __get_str(file_name))
+);
+
+#endif /* _TRACE_FSNOTIFY_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
diff --git a/include/trace/misc/fsnotify.h b/include/trace/misc/fsnotify.h
new file mode 100644
index 000000000000..a201e1bd6d8c
--- /dev/null
+++ b/include/trace/misc/fsnotify.h
@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Display helpers for fsnotify events
+ */
+
+#include <linux/fsnotify_backend.h>
+
+#define show_fsnotify_mask(mask) \
+	__print_flags(mask, "|", \
+		{ FS_ACCESS,		"ACCESS" }, \
+		{ FS_MODIFY,		"MODIFY" }, \
+		{ FS_ATTRIB,		"ATTRIB" }, \
+		{ FS_CLOSE_WRITE,	"CLOSE_WRITE" }, \
+		{ FS_CLOSE_NOWRITE,	"CLOSE_NOWRITE" }, \
+		{ FS_OPEN,		"OPEN" }, \
+		{ FS_MOVED_FROM,	"MOVED_FROM" }, \
+		{ FS_MOVED_TO,		"MOVED_TO" }, \
+		{ FS_CREATE,		"CREATE" }, \
+		{ FS_DELETE,		"DELETE" }, \
+		{ FS_DELETE_SELF,	"DELETE_SELF" }, \
+		{ FS_MOVE_SELF,		"MOVE_SELF" }, \
+		{ FS_OPEN_EXEC,		"OPEN_EXEC" }, \
+		{ FS_UNMOUNT,		"UNMOUNT" }, \
+		{ FS_Q_OVERFLOW,	"Q_OVERFLOW" }, \
+		{ FS_ERROR,		"ERROR" }, \
+		{ FS_OPEN_PERM,		"OPEN_PERM" }, \
+		{ FS_ACCESS_PERM,	"ACCESS_PERM" }, \
+		{ FS_OPEN_EXEC_PERM,	"OPEN_EXEC_PERM" }, \
+		{ FS_PRE_ACCESS,	"PRE_ACCESS" }, \
+		{ FS_MNT_ATTACH,	"MNT_ATTACH" }, \
+		{ FS_MNT_DETACH,	"MNT_DETACH" }, \
+		{ FS_EVENT_ON_CHILD,	"EVENT_ON_CHILD" }, \
+		{ FS_RENAME,		"RENAME" }, \
+		{ FS_DN_MULTISHOT,	"DN_MULTISHOT" }, \
+		{ FS_ISDIR,		"ISDIR" })

-- 
2.53.0