Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932338AbbGTO5k (ORCPT ); Mon, 20 Jul 2015 10:57:40 -0400 Received: from mail4.hitachi.co.jp ([133.145.228.5]:59610 "EHLO mail4.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752644AbbGTO5i (ORCPT ); Mon, 20 Jul 2015 10:57:38 -0400 Message-ID: <55AD0C5B.2010002@hitachi.com> Date: Mon, 20 Jul 2015 23:57:31 +0900 From: Masami Hiramatsu Organization: Hitachi, Ltd., Japan User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 MIME-Version: 1.0 To: Tom Zanussi , rostedt@goodmis.org CC: daniel.wagner@bmw-carit.de, namhyung@kernel.org, josh@joshtriplett.org, andi@firstfloor.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v9 21/22] tracing: Add enable_hist/disable_hist triggers References: In-Reply-To: Content-Type: text/plain; charset=iso-2022-jp Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 16443 Lines: 454 On 2015/07/17 2:22, Tom Zanussi wrote: > Similar to enable_event/disable_event triggers, these triggers enable > and disable the aggregation of events into maps rather than enabling > and disabling their writing into the trace buffer. > > They can be used to automatically start and stop hist triggers based > on a matching filter condition. > > If there's a paused hist trigger on system:event, the following would > start it when the filter condition was hit: > > # echo enable_hist:system:event [ if filter] > event/trigger > > And the following would disable a running system:event hist trigger: > > # echo disable_hist:system:event [ if filter] > event/trigger > > See Documentation/trace/events.txt for real examples. Hmm, do we really need this? Since we've already had multiple instances, if someone wants to make histogram separated from event logger, he/she can make another instance for that, and disable/enable event itself. I'm considering if we accept this methods, we'll need to accept another enable/disable triggers for each action too in the future. Thank you, > > Signed-off-by: Tom Zanussi > --- > include/linux/trace_events.h | 1 + > kernel/trace/trace.c | 11 ++++ > kernel/trace/trace.h | 32 ++++++++++ > kernel/trace/trace_events_hist.c | 115 ++++++++++++++++++++++++++++++++++++ > kernel/trace/trace_events_trigger.c | 71 ++++++++++++---------- > 5 files changed, 199 insertions(+), 31 deletions(-) > > diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h > index 0faf48b..0f3ffdd 100644 > --- a/include/linux/trace_events.h > +++ b/include/linux/trace_events.h > @@ -411,6 +411,7 @@ enum event_trigger_type { > ETT_STACKTRACE = (1 << 2), > ETT_EVENT_ENABLE = (1 << 3), > ETT_EVENT_HIST = (1 << 4), > + ETT_HIST_ENABLE = (1 << 5), > }; > > extern int filter_match_preds(struct event_filter *filter, void *rec); > diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c > index 16c64a2..c581750 100644 > --- a/kernel/trace/trace.c > +++ b/kernel/trace/trace.c > @@ -3761,6 +3761,10 @@ static const char readme_msg[] = > "\t trigger: traceon, traceoff\n" > "\t enable_event::\n" > "\t disable_event::\n" > +#ifdef CONFIG_HIST_TRIGGERS > + "\t enable_hist::\n" > + "\t disable_hist::\n" > +#endif > #ifdef CONFIG_STACKTRACE > "\t\t stacktrace\n" > #endif > @@ -3836,6 +3840,13 @@ static const char readme_msg[] = > "\t restart a paused hist trigger.\n\n" > "\t The 'clear' param will clear the contents of a running hist\n" > "\t trigger and leave its current paused/active state.\n\n" > + "\t The enable_hist and disable_hist triggers can be used to\n" > + "\t have one event conditionally start and stop another event's\n" > + "\t already-attached hist trigger. Any number of enable_hist\n" > + "\t and disable_hist triggers can be attached to a given event,\n" > + "\t allowing that event to kick off and stop aggregations on\n" > + "\t a host of other events. See Documentation/trace/events.txt\n" > + "\t for examples.\n" > #endif > ; > > diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h > index e6cb781..5e2e3b0 100644 > --- a/kernel/trace/trace.h > +++ b/kernel/trace/trace.h > @@ -1102,8 +1102,10 @@ extern const struct file_operations event_hist_fops; > > #ifdef CONFIG_HIST_TRIGGERS > extern int register_trigger_hist_cmd(void); > +extern int register_trigger_hist_enable_disable_cmds(void); > #else > static inline int register_trigger_hist_cmd(void) { return 0; } > +static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; } > #endif > > extern int register_trigger_cmds(void); > @@ -1121,6 +1123,34 @@ struct event_trigger_data { > struct list_head list; > }; > > +/* Avoid typos */ > +#define ENABLE_EVENT_STR "enable_event" > +#define DISABLE_EVENT_STR "disable_event" > +#define ENABLE_HIST_STR "enable_hist" > +#define DISABLE_HIST_STR "disable_hist" > + > +struct enable_trigger_data { > + struct trace_event_file *file; > + bool enable; > + bool hist; > +}; > + > +extern int event_enable_trigger_print(struct seq_file *m, > + struct event_trigger_ops *ops, > + struct event_trigger_data *data); > +extern void event_enable_trigger_free(struct event_trigger_ops *ops, > + struct event_trigger_data *data); > +extern int event_enable_trigger_func(struct event_command *cmd_ops, > + struct trace_event_file *file, > + char *glob, char *cmd, char *param); > +extern int event_enable_register_trigger(char *glob, > + struct event_trigger_ops *ops, > + struct event_trigger_data *data, > + struct trace_event_file *file); > +extern void event_enable_unregister_trigger(char *glob, > + struct event_trigger_ops *ops, > + struct event_trigger_data *test, > + struct trace_event_file *file); > extern void trigger_data_free(struct event_trigger_data *data); > extern int event_trigger_init(struct event_trigger_ops *ops, > struct event_trigger_data *data); > @@ -1134,6 +1164,8 @@ extern int set_trigger_filter(char *filter_str, > struct event_trigger_data *trigger_data, > struct trace_event_file *file); > extern int register_event_command(struct event_command *cmd); > +extern int unregister_event_command(struct event_command *cmd); > +extern int register_trigger_hist_enable_disable_cmds(void); > > /** > * struct event_trigger_ops - callbacks for trace event triggers > diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c > index 4ba7645..6a43611 100644 > --- a/kernel/trace/trace_events_hist.c > +++ b/kernel/trace/trace_events_hist.c > @@ -1345,3 +1345,118 @@ __init int register_trigger_hist_cmd(void) > > return ret; > } > + > +static void > +hist_enable_trigger(struct event_trigger_data *data, void *rec) > +{ > + struct enable_trigger_data *enable_data = data->private_data; > + struct event_trigger_data *test; > + > + list_for_each_entry_rcu(test, &enable_data->file->triggers, list) { > + if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { > + if (enable_data->enable) > + test->paused = false; > + else > + test->paused = true; > + break; > + } > + } > +} > + > +static void > +hist_enable_count_trigger(struct event_trigger_data *data, void *rec) > +{ > + if (!data->count) > + return; > + > + if (data->count != -1) > + (data->count)--; > + > + hist_enable_trigger(data, rec); > +} > + > +static struct event_trigger_ops hist_enable_trigger_ops = { > + .func = hist_enable_trigger, > + .print = event_enable_trigger_print, > + .init = event_trigger_init, > + .free = event_enable_trigger_free, > +}; > + > +static struct event_trigger_ops hist_enable_count_trigger_ops = { > + .func = hist_enable_count_trigger, > + .print = event_enable_trigger_print, > + .init = event_trigger_init, > + .free = event_enable_trigger_free, > +}; > + > +static struct event_trigger_ops hist_disable_trigger_ops = { > + .func = hist_enable_trigger, > + .print = event_enable_trigger_print, > + .init = event_trigger_init, > + .free = event_enable_trigger_free, > +}; > + > +static struct event_trigger_ops hist_disable_count_trigger_ops = { > + .func = hist_enable_count_trigger, > + .print = event_enable_trigger_print, > + .init = event_trigger_init, > + .free = event_enable_trigger_free, > +}; > + > +static struct event_trigger_ops * > +hist_enable_get_trigger_ops(char *cmd, char *param) > +{ > + struct event_trigger_ops *ops; > + bool enable; > + > + enable = (strcmp(cmd, ENABLE_HIST_STR) == 0); > + > + if (enable) > + ops = param ? &hist_enable_count_trigger_ops : > + &hist_enable_trigger_ops; > + else > + ops = param ? &hist_disable_count_trigger_ops : > + &hist_disable_trigger_ops; > + > + return ops; > +} > + > +static struct event_command trigger_hist_enable_cmd = { > + .name = ENABLE_HIST_STR, > + .trigger_type = ETT_HIST_ENABLE, > + .func = event_enable_trigger_func, > + .reg = event_enable_register_trigger, > + .unreg = event_enable_unregister_trigger, > + .get_trigger_ops = hist_enable_get_trigger_ops, > + .set_filter = set_trigger_filter, > +}; > + > +static struct event_command trigger_hist_disable_cmd = { > + .name = DISABLE_HIST_STR, > + .trigger_type = ETT_HIST_ENABLE, > + .func = event_enable_trigger_func, > + .reg = event_enable_register_trigger, > + .unreg = event_enable_unregister_trigger, > + .get_trigger_ops = hist_enable_get_trigger_ops, > + .set_filter = set_trigger_filter, > +}; > + > +static __init void unregister_trigger_hist_enable_disable_cmds(void) > +{ > + unregister_event_command(&trigger_hist_enable_cmd); > + unregister_event_command(&trigger_hist_disable_cmd); > +} > + > +__init int register_trigger_hist_enable_disable_cmds(void) > +{ > + int ret; > + > + ret = register_event_command(&trigger_hist_enable_cmd); > + if (WARN_ON(ret < 0)) > + return ret; > + ret = register_event_command(&trigger_hist_disable_cmd); > + if (WARN_ON(ret < 0)) > + unregister_trigger_hist_enable_disable_cmds(); > + > + return ret; > +} > diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c > index e80f30b..9490d8f 100644 > --- a/kernel/trace/trace_events_trigger.c > +++ b/kernel/trace/trace_events_trigger.c > @@ -338,7 +338,7 @@ __init int register_event_command(struct event_command *cmd) > * Currently we only unregister event commands from __init, so mark > * this __init too. > */ > -static __init int unregister_event_command(struct event_command *cmd) > +__init int unregister_event_command(struct event_command *cmd) > { > struct event_command *p, *n; > int ret = -ENODEV; > @@ -1052,15 +1052,6 @@ static __init void unregister_trigger_traceon_traceoff_cmds(void) > unregister_event_command(&trigger_traceoff_cmd); > } > > -/* Avoid typos */ > -#define ENABLE_EVENT_STR "enable_event" > -#define DISABLE_EVENT_STR "disable_event" > - > -struct enable_trigger_data { > - struct trace_event_file *file; > - bool enable; > -}; > - > static void > event_enable_trigger(struct event_trigger_data *data, void *rec) > { > @@ -1090,14 +1081,16 @@ event_enable_count_trigger(struct event_trigger_data *data, void *rec) > event_enable_trigger(data, rec); > } > > -static int > -event_enable_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, > - struct event_trigger_data *data) > +int event_enable_trigger_print(struct seq_file *m, > + struct event_trigger_ops *ops, > + struct event_trigger_data *data) > { > struct enable_trigger_data *enable_data = data->private_data; > > seq_printf(m, "%s:%s:%s", > - enable_data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR, > + enable_data->hist ? > + (enable_data->enable ? ENABLE_HIST_STR : DISABLE_HIST_STR) : > + (enable_data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR), > enable_data->file->event_call->class->system, > trace_event_name(enable_data->file->event_call)); > > @@ -1114,9 +1107,8 @@ event_enable_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, > return 0; > } > > -static void > -event_enable_trigger_free(struct event_trigger_ops *ops, > - struct event_trigger_data *data) > +void event_enable_trigger_free(struct event_trigger_ops *ops, > + struct event_trigger_data *data) > { > struct enable_trigger_data *enable_data = data->private_data; > > @@ -1161,10 +1153,9 @@ static struct event_trigger_ops event_disable_count_trigger_ops = { > .free = event_enable_trigger_free, > }; > > -static int > -event_enable_trigger_func(struct event_command *cmd_ops, > - struct trace_event_file *file, > - char *glob, char *cmd, char *param) > +int event_enable_trigger_func(struct event_command *cmd_ops, > + struct trace_event_file *file, > + char *glob, char *cmd, char *param) > { > struct trace_event_file *event_enable_file; > struct enable_trigger_data *enable_data; > @@ -1173,6 +1164,7 @@ event_enable_trigger_func(struct event_command *cmd_ops, > struct trace_array *tr = file->tr; > const char *system; > const char *event; > + bool hist = false; > char *trigger; > char *number; > bool enable; > @@ -1197,8 +1189,15 @@ event_enable_trigger_func(struct event_command *cmd_ops, > if (!event_enable_file) > goto out; > > - enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; > +#ifdef CONFIG_HIST_TRIGGERS > + hist = ((strcmp(cmd, ENABLE_HIST_STR) == 0) || > + (strcmp(cmd, DISABLE_HIST_STR) == 0)); > > + enable = ((strcmp(cmd, ENABLE_EVENT_STR) == 0) || > + (strcmp(cmd, ENABLE_HIST_STR) == 0)); > +#else > + enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; > +#endif > trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); > > ret = -ENOMEM; > @@ -1218,6 +1217,7 @@ event_enable_trigger_func(struct event_command *cmd_ops, > INIT_LIST_HEAD(&trigger_data->list); > RCU_INIT_POINTER(trigger_data->filter, NULL); > > + enable_data->hist = hist; > enable_data->enable = enable; > enable_data->file = event_enable_file; > trigger_data->private_data = enable_data; > @@ -1295,10 +1295,10 @@ event_enable_trigger_func(struct event_command *cmd_ops, > goto out; > } > > -static int event_enable_register_trigger(char *glob, > - struct event_trigger_ops *ops, > - struct event_trigger_data *data, > - struct trace_event_file *file) > +int event_enable_register_trigger(char *glob, > + struct event_trigger_ops *ops, > + struct event_trigger_data *data, > + struct trace_event_file *file) > { > struct enable_trigger_data *enable_data = data->private_data; > struct enable_trigger_data *test_enable_data; > @@ -1308,6 +1308,8 @@ static int event_enable_register_trigger(char *glob, > list_for_each_entry_rcu(test, &file->triggers, list) { > test_enable_data = test->private_data; > if (test_enable_data && > + (test->cmd_ops->trigger_type == > + data->cmd_ops->trigger_type) && > (test_enable_data->file == enable_data->file)) { > ret = -EEXIST; > goto out; > @@ -1333,10 +1335,10 @@ out: > return ret; > } > > -static void event_enable_unregister_trigger(char *glob, > - struct event_trigger_ops *ops, > - struct event_trigger_data *test, > - struct trace_event_file *file) > +void event_enable_unregister_trigger(char *glob, > + struct event_trigger_ops *ops, > + struct event_trigger_data *test, > + struct trace_event_file *file) > { > struct enable_trigger_data *test_enable_data = test->private_data; > struct enable_trigger_data *enable_data; > @@ -1346,6 +1348,8 @@ static void event_enable_unregister_trigger(char *glob, > list_for_each_entry_rcu(data, &file->triggers, list) { > enable_data = data->private_data; > if (enable_data && > + (data->cmd_ops->trigger_type == > + test->cmd_ops->trigger_type) && > (enable_data->file == test_enable_data->file)) { > unregistered = true; > list_del_rcu(&data->list); > @@ -1365,8 +1369,12 @@ event_enable_get_trigger_ops(char *cmd, char *param) > struct event_trigger_ops *ops; > bool enable; > > +#ifdef CONFIG_HIST_TRIGGERS > + enable = ((strcmp(cmd, ENABLE_EVENT_STR) == 0) || > + (strcmp(cmd, ENABLE_HIST_STR) == 0)); > +#else > enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; > - > +#endif > if (enable) > ops = param ? &event_enable_count_trigger_ops : > &event_enable_trigger_ops; > @@ -1437,6 +1445,7 @@ __init int register_trigger_cmds(void) > register_trigger_snapshot_cmd(); > register_trigger_stacktrace_cmd(); > register_trigger_enable_disable_cmds(); > + register_trigger_hist_enable_disable_cmds(); > register_trigger_hist_cmd(); > > return 0; > -- Masami HIRAMATSU Linux Technology Research Center, System Productivity Research Dept. Center for Technology Innovation - Systems Engineering Hitachi, Ltd., Research & Development Group E-mail: masami.hiramatsu.pt@hitachi.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/