tracing/events: Add module tracepoints
Add trace points to trace module_load, module_free, module_get,
module_put and module_request, and use trace_event facility to
get the trace output.
Here's the sample output:
TASK-PID CPU# TIMESTAMP FUNCTION
| | | | |
<...>-42 [000] 1.758380: module_request: fb0 wait=1 call_site=fb_open
...
<...>-60 [000] 3.269403: module_load: scsi_wait_scan
<...>-60 [000] 3.269432: module_put: scsi_wait_scan call_site=sys_init_module refcnt=0
<...>-61 [001] 3.273168: module_free: scsi_wait_scan
...
<...>-1021 [000] 13.836081: module_load: sunrpc
<...>-1021 [000] 13.840589: module_put: sunrpc call_site=sys_init_module refcnt=-1
<...>-1027 [000] 13.848098: module_get: sunrpc call_site=try_module_get refcnt=0
<...>-1027 [000] 13.848308: module_get: sunrpc call_site=get_filesystem refcnt=1
<...>-1027 [000] 13.848692: module_put: sunrpc call_site=put_filesystem refcnt=0
...
modprobe-2587 [001] 1088.437213: module_load: trace_events_sample F
modprobe-2587 [001] 1088.437786: module_put: trace_events_sample call_site=sys_init_module refcnt=0
Note:
- the taints flag can be 'F', 'C' and/or 'P' if mod->taints != 0
- the module refcnt is percpu, so it can be negative in a
specific cpu
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
LKML-Reference: <4A891B3C.5030608@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/trace/events/module.h b/include/trace/events/module.h
new file mode 100644
index 0000000..84160fb
--- /dev/null
+++ b/include/trace/events/module.h
@@ -0,0 +1,126 @@
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM module
+
+#if !defined(_TRACE_MODULE_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_MODULE_H
+
+#include <linux/tracepoint.h>
+
+#ifdef CONFIG_MODULES
+
+struct module;
+
+#define show_module_flags(flags) __print_flags(flags, "", \
+ { (1UL << TAINT_PROPRIETARY_MODULE), "P" }, \
+ { (1UL << TAINT_FORCED_MODULE), "F" }, \
+ { (1UL << TAINT_CRAP), "C" })
+
+TRACE_EVENT(module_load,
+
+ TP_PROTO(struct module *mod),
+
+ TP_ARGS(mod),
+
+ TP_STRUCT__entry(
+ __field( unsigned int, taints )
+ __string( name, mod->name )
+ ),
+
+ TP_fast_assign(
+ __entry->taints = mod->taints;
+ __assign_str(name, mod->name);
+ ),
+
+ TP_printk("%s %s", __get_str(name), show_module_flags(__entry->taints))
+);
+
+TRACE_EVENT(module_free,
+
+ TP_PROTO(struct module *mod),
+
+ TP_ARGS(mod),
+
+ TP_STRUCT__entry(
+ __string( name, mod->name )
+ ),
+
+ TP_fast_assign(
+ __assign_str(name, mod->name);
+ ),
+
+ TP_printk("%s", __get_str(name))
+);
+
+TRACE_EVENT(module_get,
+
+ TP_PROTO(struct module *mod, unsigned long ip, int refcnt),
+
+ TP_ARGS(mod, ip, refcnt),
+
+ TP_STRUCT__entry(
+ __field( unsigned long, ip )
+ __field( int, refcnt )
+ __string( name, mod->name )
+ ),
+
+ TP_fast_assign(
+ __entry->ip = ip;
+ __entry->refcnt = refcnt;
+ __assign_str(name, mod->name);
+ ),
+
+ TP_printk("%s call_site=%pf refcnt=%d",
+ __get_str(name), (void *)__entry->ip, __entry->refcnt)
+);
+
+TRACE_EVENT(module_put,
+
+ TP_PROTO(struct module *mod, unsigned long ip, int refcnt),
+
+ TP_ARGS(mod, ip, refcnt),
+
+ TP_STRUCT__entry(
+ __field( unsigned long, ip )
+ __field( int, refcnt )
+ __string( name, mod->name )
+ ),
+
+ TP_fast_assign(
+ __entry->ip = ip;
+ __entry->refcnt = refcnt;
+ __assign_str(name, mod->name);
+ ),
+
+ TP_printk("%s call_site=%pf refcnt=%d",
+ __get_str(name), (void *)__entry->ip, __entry->refcnt)
+);
+
+TRACE_EVENT(module_request,
+
+ TP_PROTO(char *name, bool wait, unsigned long ip),
+
+ TP_ARGS(name, wait, ip),
+
+ TP_STRUCT__entry(
+ __field( bool, wait )
+ __field( unsigned long, ip )
+ __string( name, name )
+ ),
+
+ TP_fast_assign(
+ __entry->wait = wait;
+ __entry->ip = ip;
+ __assign_str(name, name);
+ ),
+
+ TP_printk("%s wait=%d call_site=%pf",
+ __get_str(name), (int)__entry->wait, (void *)__entry->ip)
+);
+
+#endif /* CONFIG_MODULES */
+
+#endif /* _TRACE_MODULE_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
+