From 7ead8b8313d92b3a69a1a61b0dcbc4cd66c960dc Mon Sep 17 00:00:00 2001 From: Li Zefan Date: Mon, 17 Aug 2009 16:56:28 +0800 Subject: 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 Acked-by: Rusty Russell Cc: Steven Rostedt Cc: Frederic Weisbecker Cc: Rusty Russell LKML-Reference: <4A891B3C.5030608@cn.fujitsu.com> Signed-off-by: Ingo Molnar --- include/linux/module.h | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) (limited to 'include/linux/module.h') diff --git a/include/linux/module.h b/include/linux/module.h index 098bdb7bfac..f8f92d015ef 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -17,10 +17,12 @@ #include #include #include -#include +#include #include +#include + /* Not Yet Implemented */ #define MODULE_SUPPORTED_DEVICE(name) @@ -462,7 +464,10 @@ static inline local_t *__module_ref_addr(struct module *mod, int cpu) static inline void __module_get(struct module *module) { if (module) { - local_inc(__module_ref_addr(module, get_cpu())); + unsigned int cpu = get_cpu(); + local_inc(__module_ref_addr(module, cpu)); + trace_module_get(module, _THIS_IP_, + local_read(__module_ref_addr(module, cpu))); put_cpu(); } } @@ -473,8 +478,11 @@ static inline int try_module_get(struct module *module) if (module) { unsigned int cpu = get_cpu(); - if (likely(module_is_live(module))) + if (likely(module_is_live(module))) { local_inc(__module_ref_addr(module, cpu)); + trace_module_get(module, _THIS_IP_, + local_read(__module_ref_addr(module, cpu))); + } else ret = 0; put_cpu(); -- cgit v1.2.3-70-g09d2