tracing: Create class struct for events
This patch creates a ftrace_event_class struct that event structs point to.
This class struct will be made to hold information to modify the
events. Currently the class struct only holds the events system name.
This patch slightly increases the size, but this change lays the ground work
of other changes to make the footprint of tracepoints smaller.
With 82 standard tracepoints, and 618 system call tracepoints
(two tracepoints per syscall: enter and exit):
text data bss dec hex filename
4913961 1088356 861512 6863829 68bbd5 vmlinux.orig
4914025 1088868 861512 6864405 68be15 vmlinux.class
This patch also cleans up some stale comments in ftrace.h.
v2: Fixed missing semi-colon in macro.
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h
index 39e71b0..496eea8 100644
--- a/include/linux/ftrace_event.h
+++ b/include/linux/ftrace_event.h
@@ -113,10 +113,14 @@
struct event_filter;
+struct ftrace_event_class {
+ char *system;
+};
+
struct ftrace_event_call {
struct list_head list;
+ struct ftrace_event_class *class;
char *name;
- char *system;
struct dentry *dir;
struct trace_event *event;
int enabled;
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index 057929b..ac5791d 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -134,6 +134,8 @@
#define __SC_STR_TDECL5(t, a, ...) #t, __SC_STR_TDECL4(__VA_ARGS__)
#define __SC_STR_TDECL6(t, a, ...) #t, __SC_STR_TDECL5(__VA_ARGS__)
+extern struct ftrace_event_class event_class_syscalls;
+
#define SYSCALL_TRACE_ENTER_EVENT(sname) \
static const struct syscall_metadata __syscall_meta_##sname; \
static struct ftrace_event_call \
@@ -146,7 +148,7 @@
__attribute__((section("_ftrace_events"))) \
event_enter_##sname = { \
.name = "sys_enter"#sname, \
- .system = "syscalls", \
+ .class = &event_class_syscalls, \
.event = &enter_syscall_print_##sname, \
.raw_init = init_syscall_trace, \
.define_fields = syscall_enter_define_fields, \
@@ -168,7 +170,7 @@
__attribute__((section("_ftrace_events"))) \
event_exit_##sname = { \
.name = "sys_exit"#sname, \
- .system = "syscalls", \
+ .class = &event_class_syscalls, \
.event = &exit_syscall_print_##sname, \
.raw_init = init_syscall_trace, \
.define_fields = syscall_exit_define_fields, \
diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index 75dd778..7dcdfd8 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -62,7 +62,10 @@
struct trace_entry ent; \
tstruct \
char __data[0]; \
- };
+ }; \
+ \
+ static struct ftrace_event_class event_class_##name;
+
#undef DEFINE_EVENT
#define DEFINE_EVENT(template, name, proto, args) \
static struct ftrace_event_call \
@@ -430,22 +433,6 @@
*
* Override the macros in <trace/trace_events.h> to include the following:
*
- * static void ftrace_event_<call>(proto)
- * {
- * event_trace_printk(_RET_IP_, "<call>: " <fmt>);
- * }
- *
- * static int ftrace_reg_event_<call>(struct ftrace_event_call *unused)
- * {
- * return register_trace_<call>(ftrace_event_<call>);
- * }
- *
- * static void ftrace_unreg_event_<call>(struct ftrace_event_call *unused)
- * {
- * unregister_trace_<call>(ftrace_event_<call>);
- * }
- *
- *
* For those macros defined with TRACE_EVENT:
*
* static struct ftrace_event_call event_<call>;
@@ -497,17 +484,21 @@
*
* static const char print_fmt_<call>[] = <TP_printk>;
*
+ * static struct ftrace_event_class __used event_class_<template> = {
+ * .system = "<system>",
+ * };
+ *
* static struct ftrace_event_call __used
* __attribute__((__aligned__(4)))
* __attribute__((section("_ftrace_events"))) event_<call> = {
* .name = "<call>",
- * .system = "<system>",
+ * .class = event_class_<template>,
* .raw_init = trace_event_raw_init,
- * .regfunc = ftrace_reg_event_<call>,
- * .unregfunc = ftrace_unreg_event_<call>,
+ * .regfunc = ftrace_raw_reg_event_<call>,
+ * .unregfunc = ftrace_raw_unreg_event_<call>,
* .print_fmt = print_fmt_<call>,
* .define_fields = ftrace_define_fields_<call>,
- * }
+ * };
*
*/
@@ -627,7 +618,10 @@
#undef DECLARE_EVENT_CLASS
#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print) \
-static const char print_fmt_##call[] = print;
+static const char print_fmt_##call[] = print; \
+static struct ftrace_event_class __used event_class_##call = { \
+ .system = __stringify(TRACE_SYSTEM) \
+};
#undef DEFINE_EVENT
#define DEFINE_EVENT(template, call, proto, args) \
@@ -636,7 +630,7 @@
__attribute__((__aligned__(4))) \
__attribute__((section("_ftrace_events"))) event_##call = { \
.name = #call, \
- .system = __stringify(TRACE_SYSTEM), \
+ .class = &event_class_##template, \
.event = &ftrace_event_type_##call, \
.raw_init = trace_event_raw_init, \
.regfunc = ftrace_raw_reg_event_##call, \
@@ -644,7 +638,7 @@
.print_fmt = print_fmt_##template, \
.define_fields = ftrace_define_fields_##template, \
_TRACE_PERF_INIT(call) \
-}
+};
#undef DEFINE_EVENT_PRINT
#define DEFINE_EVENT_PRINT(template, call, proto, args, print) \
@@ -655,7 +649,7 @@
__attribute__((__aligned__(4))) \
__attribute__((section("_ftrace_events"))) event_##call = { \
.name = #call, \
- .system = __stringify(TRACE_SYSTEM), \
+ .class = &event_class_##template, \
.event = &ftrace_event_type_##call, \
.raw_init = trace_event_raw_init, \
.regfunc = ftrace_raw_reg_event_##call, \
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index c697c70..2f54b48 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -176,10 +176,10 @@
if (match &&
strcmp(match, call->name) != 0 &&
- strcmp(match, call->system) != 0)
+ strcmp(match, call->class->system) != 0)
continue;
- if (sub && strcmp(sub, call->system) != 0)
+ if (sub && strcmp(sub, call->class->system) != 0)
continue;
if (event && strcmp(event, call->name) != 0)
@@ -355,8 +355,8 @@
{
struct ftrace_event_call *call = v;
- if (strcmp(call->system, TRACE_SYSTEM) != 0)
- seq_printf(m, "%s:", call->system);
+ if (strcmp(call->class->system, TRACE_SYSTEM) != 0)
+ seq_printf(m, "%s:", call->class->system);
seq_printf(m, "%s\n", call->name);
return 0;
@@ -453,7 +453,7 @@
if (!call->name || !call->regfunc)
continue;
- if (system && strcmp(call->system, system) != 0)
+ if (system && strcmp(call->class->system, system) != 0)
continue;
/*
@@ -925,8 +925,8 @@
* If the trace point header did not define TRACE_SYSTEM
* then the system would be called "TRACE_SYSTEM".
*/
- if (strcmp(call->system, TRACE_SYSTEM) != 0)
- d_events = event_subsystem_dir(call->system, d_events);
+ if (strcmp(call->class->system, TRACE_SYSTEM) != 0)
+ d_events = event_subsystem_dir(call->class->system, d_events);
call->dir = debugfs_create_dir(call->name, d_events);
if (!call->dir) {
@@ -1041,7 +1041,7 @@
list_del(&call->list);
trace_destroy_fields(call);
destroy_preds(call);
- remove_subsystem_dir(call->system);
+ remove_subsystem_dir(call->class->system);
}
/* Remove an event_call */
@@ -1399,8 +1399,8 @@
* syscalls as we test.
*/
#ifndef CONFIG_EVENT_TRACE_TEST_SYSCALLS
- if (call->system &&
- strcmp(call->system, "syscalls") == 0)
+ if (call->class->system &&
+ strcmp(call->class->system, "syscalls") == 0)
continue;
#endif
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 88c0b6d..ca32960 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -628,7 +628,7 @@
if (!call->define_fields)
continue;
- if (strcmp(call->system, system->name) != 0)
+ if (strcmp(call->class->system, system->name) != 0)
continue;
err = init_preds(call);
@@ -647,7 +647,7 @@
if (!call->define_fields)
continue;
- if (strcmp(call->system, system->name) != 0)
+ if (strcmp(call->class->system, system->name) != 0)
continue;
filter_disable_preds(call);
@@ -1252,7 +1252,7 @@
if (!call->define_fields)
continue;
- if (strcmp(call->system, system->name) != 0)
+ if (strcmp(call->class->system, system->name) != 0)
continue;
/* try to see if the filter can be applied */
diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c
index e091f64..7f16e21 100644
--- a/kernel/trace/trace_export.c
+++ b/kernel/trace/trace_export.c
@@ -18,6 +18,10 @@
#undef TRACE_SYSTEM
#define TRACE_SYSTEM ftrace
+struct ftrace_event_class event_class_ftrace = {
+ .system = __stringify(TRACE_SYSTEM),
+};
+
/* not needed for this file */
#undef __field_struct
#define __field_struct(type, item)
@@ -160,7 +164,7 @@
__attribute__((section("_ftrace_events"))) event_##call = { \
.name = #call, \
.id = type, \
- .system = __stringify(TRACE_SYSTEM), \
+ .class = &event_class_ftrace, \
.raw_init = ftrace_raw_init_event, \
.print_fmt = print, \
.define_fields = ftrace_define_fields_##call, \
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 1251e36..eda220b 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -332,8 +332,8 @@
goto error;
}
- tp->call.system = kstrdup(group, GFP_KERNEL);
- if (!tp->call.system)
+ tp->call.class->system = kstrdup(group, GFP_KERNEL);
+ if (!tp->call.class->system)
goto error;
INIT_LIST_HEAD(&tp->list);
@@ -361,7 +361,7 @@
for (i = 0; i < tp->nr_args; i++)
free_probe_arg(&tp->args[i]);
- kfree(tp->call.system);
+ kfree(tp->call.class->system);
kfree(tp->call.name);
kfree(tp->symbol);
kfree(tp);
@@ -374,7 +374,7 @@
list_for_each_entry(tp, &probe_list, list)
if (strcmp(tp->call.name, event) == 0 &&
- strcmp(tp->call.system, group) == 0)
+ strcmp(tp->call.class->system, group) == 0)
return tp;
return NULL;
}
@@ -399,7 +399,7 @@
mutex_lock(&probe_lock);
/* register as an event */
- old_tp = find_probe_event(tp->call.name, tp->call.system);
+ old_tp = find_probe_event(tp->call.name, tp->call.class->system);
if (old_tp) {
/* delete old event */
unregister_trace_probe(old_tp);
@@ -798,7 +798,7 @@
char buf[MAX_ARGSTR_LEN + 1];
seq_printf(m, "%c", probe_is_return(tp) ? 'r' : 'p');
- seq_printf(m, ":%s/%s", tp->call.system, tp->call.name);
+ seq_printf(m, ":%s/%s", tp->call.class->system, tp->call.name);
if (!tp->symbol)
seq_printf(m, " 0x%p", tp->rp.kp.addr);
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 4d6d711..d036a74 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -15,6 +15,10 @@
static DECLARE_BITMAP(enabled_enter_syscalls, NR_syscalls);
static DECLARE_BITMAP(enabled_exit_syscalls, NR_syscalls);
+struct ftrace_event_class event_class_syscalls = {
+ .system = "syscalls"
+};
+
extern unsigned long __start_syscalls_metadata[];
extern unsigned long __stop_syscalls_metadata[];