From patchwork Tue Jun 2 00:37:48 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masami Hiramatsu X-Patchwork-Id: 27348 Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by demeter.kernel.org (8.14.2/8.14.2) with ESMTP id n520cVBt005838 for ; Tue, 2 Jun 2009 00:38:31 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757415AbZFBAem (ORCPT ); Mon, 1 Jun 2009 20:34:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757413AbZFBAem (ORCPT ); Mon, 1 Jun 2009 20:34:42 -0400 Received: from mx2.redhat.com ([66.187.237.31]:36900 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757018AbZFBAei (ORCPT ); Mon, 1 Jun 2009 20:34:38 -0400 Received: from int-mx2.corp.redhat.com (int-mx2.corp.redhat.com [172.16.27.26]) by mx2.redhat.com (8.13.8/8.13.8) with ESMTP id n520Yaot002495; Mon, 1 Jun 2009 20:34:36 -0400 Received: from ns3.rdu.redhat.com (ns3.rdu.redhat.com [10.11.255.199]) by int-mx2.corp.redhat.com (8.13.1/8.13.1) with ESMTP id n520YZVT017261; Mon, 1 Jun 2009 20:34:35 -0400 Received: from localhost.localdomain (dhcp-100-3-156.bos.redhat.com [10.16.3.156]) by ns3.rdu.redhat.com (8.13.8/8.13.8) with ESMTP id n520YXpJ016285; Mon, 1 Jun 2009 20:34:33 -0400 From: Masami Hiramatsu Subject: [PATCH -tip v9 6/7] tracing: ftrace dynamic ftrace_event_call support To: Ingo Molnar , Steven Rostedt , lkml Cc: systemtap , kvm , DLE , Masami Hiramatsu , Steven Rostedt , Ingo Molnar , Tom Zanussi , Frederic Weisbecker Date: Mon, 01 Jun 2009 20:37:48 -0400 Message-ID: <20090602003748.29255.13561.stgit@localhost.localdomain> In-Reply-To: <20090602003709.29255.48248.stgit@localhost.localdomain> References: <20090602003709.29255.48248.stgit@localhost.localdomain> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.58 on 172.16.27.26 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Add dynamic ftrace_event_call support to ftrace. Trace engines can adds new ftrace_event_call to ftrace on the fly. Each operator functions of the call takes a ftrace_event_call data structure as an argument, because these functions may be shared among several ftrace_event_calls. Changes from v8: - Lock event_mutex in trace_add/remove_event_call(). - Add __trace_add/remove_event_call() for internal use. - Rename "dummy" variables to "unused". Signed-off-by: Masami Hiramatsu Cc: Steven Rostedt Cc: Ingo Molnar Cc: Tom Zanussi Cc: Frederic Weisbecker --- include/linux/ftrace_event.h | 13 +++++--- include/trace/ftrace.h | 22 +++++++------ kernel/trace/trace_events.c | 70 ++++++++++++++++++++++++++++++++---------- kernel/trace/trace_export.c | 27 ++++++++-------- 4 files changed, 85 insertions(+), 47 deletions(-) diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h index bbf40f6..e25f3a4 100644 --- a/include/linux/ftrace_event.h +++ b/include/linux/ftrace_event.h @@ -108,12 +108,13 @@ struct ftrace_event_call { struct dentry *dir; struct trace_event *event; int enabled; - int (*regfunc)(void); - void (*unregfunc)(void); + int (*regfunc)(struct ftrace_event_call *); + void (*unregfunc)(struct ftrace_event_call *); int id; - int (*raw_init)(void); - int (*show_format)(struct trace_seq *s); - int (*define_fields)(void); + int (*raw_init)(struct ftrace_event_call *); + int (*show_format)(struct ftrace_event_call *, + struct trace_seq *); + int (*define_fields)(struct ftrace_event_call *); struct list_head fields; int filter_active; void *filter; @@ -138,6 +139,8 @@ extern int filter_current_check_discard(struct ftrace_event_call *call, extern int trace_define_field(struct ftrace_event_call *call, char *type, char *name, int offset, int size, int is_signed); +extern int trace_add_event_call(struct ftrace_event_call *call); +extern void trace_remove_event_call(struct ftrace_event_call *call); #define is_signed_type(type) (((type)(-1)) < 0) diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h index b4ec83a..e163e4b 100644 --- a/include/trace/ftrace.h +++ b/include/trace/ftrace.h @@ -229,7 +229,8 @@ ftrace_raw_output_##call(struct trace_iterator *iter, int flags) \ #undef TRACE_EVENT #define TRACE_EVENT(call, proto, args, tstruct, func, print) \ static int \ -ftrace_format_##call(struct trace_seq *s) \ +ftrace_format_##call(struct ftrace_event_call *event_call, \ + struct trace_seq *s) \ { \ struct ftrace_raw_##call field __attribute__((unused)); \ int ret = 0; \ @@ -269,10 +270,9 @@ ftrace_format_##call(struct trace_seq *s) \ #undef TRACE_EVENT #define TRACE_EVENT(call, proto, args, tstruct, func, print) \ int \ -ftrace_define_fields_##call(void) \ +ftrace_define_fields_##call(struct ftrace_event_call *event_call) \ { \ struct ftrace_raw_##call field; \ - struct ftrace_event_call *event_call = &event_##call; \ int ret; \ \ __common_field(int, type, 1); \ @@ -298,7 +298,7 @@ ftrace_define_fields_##call(void) \ * event_trace_printk(_RET_IP_, ": " ); * } * - * static int ftrace_reg_event_(void) + * static int ftrace_reg_event_(struct ftrace_event_call *unused) * { * int ret; * @@ -309,7 +309,7 @@ ftrace_define_fields_##call(void) \ * return ret; * } * - * static void ftrace_unreg_event_(void) + * static void ftrace_unreg_event_(struct ftrace_event_call *unused) * { * unregister_trace_(ftrace_event_); * } @@ -342,7 +342,7 @@ ftrace_define_fields_##call(void) \ * trace_current_buffer_unlock_commit(event, irq_flags, pc); * } * - * static int ftrace_raw_reg_event_(void) + * static int ftrace_raw_reg_event_(struct ftrace_event_call *unused) * { * int ret; * @@ -353,7 +353,7 @@ ftrace_define_fields_##call(void) \ * return ret; * } * - * static void ftrace_unreg_event_(void) + * static void ftrace_unreg_event_(struct ftrace_event_call *unused) * { * unregister_trace_(ftrace_raw_event_); * } @@ -362,7 +362,7 @@ ftrace_define_fields_##call(void) \ * .trace = ftrace_raw_output_, <-- stage 2 * }; * - * static int ftrace_raw_init_event_(void) + * static int ftrace_raw_init_event_(struct ftrace_event_call *unused) * { * int id; * @@ -477,7 +477,7 @@ static void ftrace_raw_event_##call(proto) \ trace_nowake_buffer_unlock_commit(event, irq_flags, pc); \ } \ \ -static int ftrace_raw_reg_event_##call(void) \ +static int ftrace_raw_reg_event_##call(struct ftrace_event_call *unused)\ { \ int ret; \ \ @@ -488,7 +488,7 @@ static int ftrace_raw_reg_event_##call(void) \ return ret; \ } \ \ -static void ftrace_raw_unreg_event_##call(void) \ +static void ftrace_raw_unreg_event_##call(struct ftrace_event_call *unused)\ { \ unregister_trace_##call(ftrace_raw_event_##call); \ } \ @@ -497,7 +497,7 @@ static struct trace_event ftrace_event_type_##call = { \ .trace = ftrace_raw_output_##call, \ }; \ \ -static int ftrace_raw_init_event_##call(void) \ +static int ftrace_raw_init_event_##call(struct ftrace_event_call *unused)\ { \ int id; \ \ diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 6c81f9c..e881428 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -60,9 +60,7 @@ err: } EXPORT_SYMBOL_GPL(trace_define_field); -#ifdef CONFIG_MODULES - -static void trace_destroy_fields(struct ftrace_event_call *call) +void trace_destroy_fields(struct ftrace_event_call *call) { struct ftrace_event_field *field, *next; @@ -74,8 +72,6 @@ static void trace_destroy_fields(struct ftrace_event_call *call) } } -#endif /* CONFIG_MODULES */ - static void ftrace_event_enable_disable(struct ftrace_event_call *call, int enable) { @@ -84,14 +80,14 @@ static void ftrace_event_enable_disable(struct ftrace_event_call *call, if (call->enabled) { call->enabled = 0; tracing_stop_cmdline_record(); - call->unregfunc(); + call->unregfunc(call); } break; case 1: if (!call->enabled) { call->enabled = 1; tracing_start_cmdline_record(); - call->regfunc(); + call->regfunc(call); } break; } @@ -558,7 +554,7 @@ event_format_read(struct file *filp, char __user *ubuf, size_t cnt, trace_seq_printf(s, "format:\n"); trace_write_header(s); - r = call->show_format(s); + r = call->show_format(call, s); if (!r) { /* * ug! The format output is bigger than a PAGE!! @@ -905,7 +901,7 @@ event_create_dir(struct ftrace_event_call *call, struct dentry *d_events, d_events = event_subsystem_dir(call->system, d_events); if (call->raw_init) { - ret = call->raw_init(); + ret = call->raw_init(call); if (ret < 0) { pr_warning("Could not initialize trace point" " events/%s\n", call->name); @@ -929,7 +925,7 @@ event_create_dir(struct ftrace_event_call *call, struct dentry *d_events, id); if (call->define_fields) { - ret = call->define_fields(); + ret = call->define_fields(call); if (ret < 0) { pr_warning("Could not initialize trace point" " events/%s\n", call->name); @@ -949,6 +945,52 @@ event_create_dir(struct ftrace_event_call *call, struct dentry *d_events, return 0; } +static int __trace_add_event_call(struct ftrace_event_call *call) +{ + struct dentry *d_events; + + if (!call->name) + return -EINVAL; + + d_events = event_trace_events_dir(); + if (!d_events) + return -ENOENT; + + list_add(&call->list, &ftrace_events); + return event_create_dir(call, d_events, &ftrace_event_id_fops, + &ftrace_enable_fops, &ftrace_event_filter_fops, + &ftrace_event_format_fops); +} + +/* Add an additional event_call dynamically */ +int trace_add_event_call(struct ftrace_event_call *call) +{ + int ret; + mutex_lock(&event_mutex); + ret = __trace_add_event_call(call); + mutex_unlock(&event_mutex); + return ret; +} + +static void __trace_remove_event_call(struct ftrace_event_call *call) +{ + ftrace_event_enable_disable(call, 0); + if (call->event) + unregister_ftrace_event(call->event); + debugfs_remove_recursive(call->dir); + list_del(&call->list); + trace_destroy_fields(call); + destroy_preds(call); +} + +/* Remove an event_call */ +void trace_remove_event_call(struct ftrace_event_call *call) +{ + mutex_lock(&event_mutex); + __trace_remove_event_call(call); + mutex_unlock(&event_mutex); +} + #define for_each_event(event, start, end) \ for (event = start; \ (unsigned long)event < (unsigned long)end; \ @@ -1053,13 +1095,7 @@ static void trace_module_remove_events(struct module *mod) list_for_each_entry_safe(call, p, &ftrace_events, list) { if (call->mod == mod) { found = true; - ftrace_event_enable_disable(call, 0); - if (call->event) - unregister_ftrace_event(call->event); - debugfs_remove_recursive(call->dir); - list_del(&call->list); - trace_destroy_fields(call); - destroy_preds(call); + __trace_remove_event_call(call); } } diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c index d06cf89..7cee79d 100644 --- a/kernel/trace/trace_export.c +++ b/kernel/trace/trace_export.c @@ -60,7 +60,7 @@ extern void __bad_type_size(void); #undef TRACE_EVENT_FORMAT #define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt) \ static int \ -ftrace_format_##call(struct trace_seq *s) \ +ftrace_format_##call(struct ftrace_event_call *dummy, struct trace_seq *s)\ { \ struct args field; \ int ret; \ @@ -76,7 +76,7 @@ ftrace_format_##call(struct trace_seq *s) \ #define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct, \ tpfmt) \ static int \ -ftrace_format_##call(struct trace_seq *s) \ +ftrace_format_##call(struct ftrace_event_call *dummy, struct trace_seq *s)\ { \ struct args field; \ int ret; \ @@ -115,10 +115,16 @@ ftrace_format_##call(struct trace_seq *s) \ #define TRACE_FIELD_SPECIAL(type_item, item, len, cmd) \ cmd; +static int ftrace_raw_init_event(struct ftrace_event_call *event_call) +{ + INIT_LIST_HEAD(&event_call->fields); + init_preds(event_call); + return 0; +} + #undef TRACE_EVENT_FORMAT #define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt) \ -int ftrace_define_fields_##call(void); \ -static int ftrace_raw_init_event_##call(void); \ +int ftrace_define_fields_##call(struct ftrace_event_call *c); \ \ struct ftrace_event_call __used \ __attribute__((__aligned__(4))) \ @@ -126,16 +132,10 @@ __attribute__((section("_ftrace_events"))) event_##call = { \ .name = #call, \ .id = proto, \ .system = __stringify(TRACE_SYSTEM), \ - .raw_init = ftrace_raw_init_event_##call, \ + .raw_init = ftrace_raw_init_event, \ .show_format = ftrace_format_##call, \ .define_fields = ftrace_define_fields_##call, \ -}; \ -static int ftrace_raw_init_event_##call(void) \ -{ \ - INIT_LIST_HEAD(&event_##call.fields); \ - init_preds(&event_##call); \ - return 0; \ -} \ +}; #undef TRACE_EVENT_FORMAT_NOFILTER #define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct, \ @@ -182,9 +182,8 @@ __attribute__((section("_ftrace_events"))) event_##call = { \ #undef TRACE_EVENT_FORMAT #define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt) \ int \ -ftrace_define_fields_##call(void) \ +ftrace_define_fields_##call(struct ftrace_event_call *event_call) \ { \ - struct ftrace_event_call *event_call = &event_##call; \ struct args field; \ int ret; \ \