ureadahead-2.6.36-trace-patch

From ee9c0b591bf16ca11bb354bc68dae75a903f3a64 Mon Sep 17 00:00:00 2001
From: Scott James Remnant <scott@ubuntu.com>
Date: Tue, 27 Oct 2009 10:05:32 +0000
Subject: [PATCH] trace: add trace events for open(), exec() and uselib()

This patch uses TRACE_EVENT to add tracepoints for the open(),
exec() and uselib() syscalls so that ureadahead can cheaply trace
the boot sequence to determine what to read to speed up the next.

It's not upstream because it will need to be rebased onto the syscall
trace events whenever that gets merged, and is a stop-gap.

Signed-off-by: Scott James Remnant <scott@ubuntu.com>
---
 fs/exec.c                 |    4 +++++
 fs/open.c                 |    4 ++
 include/trace/events/fs.h |   71 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 79 insertions(+), 0 deletions(-)
 create mode 100644 include/trace/events/fs.h

diff --git a/fs/exec.c b/fs/exec.c
index 172ceb6..c936999 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -55,6 +55,8 @@
 #include <linux/fs_struct.h>
 #include <linux/pipe_fs_i.h>

+#include <trace/events/fs.h>
+
 #include <asm/uaccess.h>
 #include <asm/mmu_context.h>
 #include <asm/tlb.h>

@@ -700,6 +702,8 @@ struct file *open_exec(const char *name)

 	fsnotify_open(file);

+	trace_open_exec(name);
+
 	err = deny_write_access(file);
 	if (err)
 		goto exit;
diff --git a/fs/open.c b/fs/open.c
index 04b9aad..41c87f3 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -33,6 +33,9 @@

 #include "internal.h"

+#define CREATE_TRACE_POINTS
+#include <trace/events/fs.h>
+
 int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs,
	struct file *filp)
 {
@@ -890,6 +893,7 @@ long do_sys_open(int dfd, const char __user *filename, int flags, int mode)
 			} else {
 				fsnotify_open(f);
 				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..e967c55
--- /dev/null
+++ b/include/trace/events/fs.h
@@ -0,0 +1,71 @@
+#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)
+);
+
+TRACE_EVENT(uselib,
+
+	TP_PROTO(char *filename),
+
+	TP_ARGS(filename),
+
+	TP_STRUCT__entry(
+		__string(	filename, filename		)
+	),
+
+	TP_fast_assign(
+		__assign_str(filename, filename);
+	),
+
+	TP_printk("\"%s\"",
+		  __get_str(filename))
+);
+
+TRACE_EVENT(open_exec,
+
+	TP_PROTO(char *filename),
+
+	TP_ARGS(filename),
+
+	TP_STRUCT__entry(
+		__string(	filename, filename		)
+	),
+
+	TP_fast_assign(
+		__assign_str(filename, filename);
+	),
+
+	TP_printk("\"%s\"",
+		  __get_str(filename))
+);
+
+#endif /* _TRACE_FS_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
--
1.6.3.3