[PATCH 1/9] tracing: Use a global field list for all syscall exit events

Steven Rostedt
2010-06-29T03:10:50Z

[-- Attachment #1: 0001-tracing-Use-a-global-field-list-for-all-syscall-exit.patch --]
[-- Type: text/plain, Size: 2827 bytes --]

From: Li Zefan <lizf@cn.fujitsu.com>

All syscall exit events have the same fields.

The kernel size drops 2.5K:

text data bss dec hex filename
7018612 2034376 7251132 16304120 f8c7f8 vmlinux.o.orig
7018612 2031888 7251132 16301632 f8be40 vmlinux.o

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4BFA3746.8070100@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
include/linux/syscalls.h | 2 --
include/trace/syscall.h | 1 -
kernel/trace/trace_syscalls.c | 7 ++++---
3 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index 7f614ce..7994bd4 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -165,7 +165,6 @@ extern struct trace_event_functions exit_syscall_print_funcs;
.enter_event = &event_enter_##sname, \
.exit_event = &event_exit_##sname, \
.enter_fields = LIST_HEAD_INIT(__syscall_meta_##sname.enter_fields), \
- .exit_fields = LIST_HEAD_INIT(__syscall_meta_##sname.exit_fields), \
};

#define SYSCALL_DEFINE0(sname) \
@@ -180,7 +179,6 @@ extern struct trace_event_functions exit_syscall_print_funcs;
.enter_event = &event_enter__##sname, \
.exit_event = &event_exit__##sname, \
.enter_fields = LIST_HEAD_INIT(__syscall_meta__##sname.enter_fields), \
- .exit_fields = LIST_HEAD_INIT(__syscall_meta__##sname.exit_fields), \
}; \
asmlinkage long sys_##sname(void)
#else
diff --git a/include/trace/syscall.h b/include/trace/syscall.h
index 257e089..31966a4 100644
--- a/include/trace/syscall.h
+++ b/include/trace/syscall.h
@@ -26,7 +26,6 @@ struct syscall_metadata {
const char **types;
const char **args;
struct list_head enter_fields;
- struct list_head exit_fields;

struct ftrace_event_call *enter_event;
struct ftrace_event_call *exit_event;
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 34e3580..bac752f 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -23,6 +23,9 @@ static int syscall_exit_register(struct ftrace_event_call *event,
static int syscall_enter_define_fields(struct ftrace_event_call *call);
static int syscall_exit_define_fields(struct ftrace_event_call *call);

+/* All syscall exit events have the same fields */
+static LIST_HEAD(syscall_exit_fields);
+
static struct list_head *
syscall_get_enter_fields(struct ftrace_event_call *call)
{
@@ -34,9 +37,7 @@ syscall_get_enter_fields(struct ftrace_event_call *call)
static struct list_head *
syscall_get_exit_fields(struct ftrace_event_call *call)
{
- struct syscall_metadata *entry = call->data;
-
- return &entry->exit_fields;
+ return &syscall_exit_fields;
}

struct trace_event_functions enter_syscall_print_funcs = {
--
1.7.1