[PATCH] trace: add trace_event for the open() syscall

[Tim Gardner]

Scott James Remnant wrote:
> This patch uses TRACE_EVENT to add a tracepoint for the open()
> syscall, in the spirit of the previous patch for sreadahead
> that added the trace with ftrace.
> 
> It's not upstream because a much better system for adding tracepoints
> for all syscalls is being worked on upstream, this is a stop-gap until
> we have that.
> 
> Signed-off-by: Scott James Remnant <scott at ubuntu.com>
> ---
>  fs/open.c                 |    4 ++++
>  include/trace/events/fs.h |   35 +++++++++++++++++++++++++++++++++++
>  2 files changed, 39 insertions(+), 0 deletions(-)
>  create mode 100644 include/trace/events/fs.h
> 
> diff --git a/fs/open.c b/fs/open.c
> index dd98e80..bc70440 100644
> --- a/fs/open.c
> +++ b/fs/open.c
> @@ -31,6 +31,9 @@
>  #include <linux/falloc.h>
>  #include <linux/fs_struct.h>
>  
> +#define CREATE_TRACE_POINTS
> +#include <trace/events/fs.h>
> +
>  int vfs_statfs(struct dentry *dentry, struct kstatfs *buf)
>  {
>  	int retval = -ENODEV;
> @@ -1040,6 +1043,7 @@ long do_sys_open(int dfd, const char __user *filename, int flags, int mode)
>  			} else {
>  				fsnotify_open(f->f_path.dentry);
>  				fd_install(fd, f);
> +				trace_do_sys_open(tmp, flags, mode);
>  			}
>  		}
>  		putname(tmp);
> diff --git a/include/trace/events/fs.h b/include/trace/events/fs.h
> new file mode 100644
> index 0000000..ae330c8
> --- /dev/null
> +++ b/include/trace/events/fs.h
> @@ -0,0 +1,35 @@
> +#undef TRACE_SYSTEM
> +#define TRACE_SYSTEM fs
> +
> +#if !defined(_TRACE_FS_H) || defined(TRACE_HEADER_MULTI_READ)
> +#define _TRACE_FS_H
> +
> +#include <linux/fs.h>
> +#include <linux/tracepoint.h>
> +
> +TRACE_EVENT(do_sys_open,
> +
> +	TP_PROTO(char *filename, int flags, int mode),
> +
> +	TP_ARGS(filename, flags, mode),
> +
> +	TP_STRUCT__entry(
> +		__string(	filename, filename		)
> +		__field(	int, flags			)
> +		__field(	int, mode			)
> +	),
> +
> +	TP_fast_assign(
> +		__assign_str(filename, filename);
> +		__entry->flags = flags;
> +		__entry->mode = mode;
> +	),
> +
> +	TP_printk("\"%s\" %x %o",
> +		  __get_str(filename), __entry->flags, __entry->mode)
> +);
> +
> +#endif /* _TRACE_FS_H */
> +
> +/* This part must be outside protection */
> +#include <trace/define_trace.h>

applied

-- 
Tim Gardner tim.gardner at canonical.com