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

[Jan Kara]

On Thu 16-04-26 10:35:06, Jeff Layton wrote:
> Add a tracepoint so we can see exactly how this is being called.
> 
> Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>

Looks good. Feel free to add:

Reviewed-by: Jan Kara <jack@xxxxxxx>

								Honza

> ---
>  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
> 
-- 
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR