diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h index 404603720650..5f89a5b0c7e6 100644 --- a/include/linux/trace_events.h +++ b/include/linux/trace_events.h @@ -408,6 +408,7 @@ 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 2238bfde799b..8430145bea12 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3807,6 +3807,10 @@ 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 @@ -3867,6 +3871,10 @@ static const char readme_msg[] = "\t The 'clear' parameter will clear the contents of a running\n" "\t hist trigger and leave its current paused/active state\n" "\t unchanged.\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. The syntax is analagous to\n" + "\t the enable_event and disable_event triggers.\n" #endif ; diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 505f8a45f426..cab1f4bfe85b 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -1166,8 +1166,10 @@ 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); @@ -1185,6 +1187,34 @@ 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); @@ -1198,6 +1228,8 @@ 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 4f4041d76926..5d4f02792440 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -1393,3 +1393,118 @@ __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 d29092afe005..d133f2094566 100644 --- a/kernel/trace/trace_events_trigger.c +++ b/kernel/trace/trace_events_trigger.c @@ -347,7 +347,7 @@ __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; @@ -1062,15 +1062,6 @@ 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) { @@ -1100,14 +1091,16 @@ 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)); @@ -1124,9 +1117,8 @@ 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; @@ -1171,10 +1163,9 @@ 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; @@ -1183,6 +1174,7 @@ 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; @@ -1207,8 +1199,15 @@ 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; @@ -1228,6 +1227,7 @@ 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; @@ -1305,10 +1305,10 @@ 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; @@ -1318,6 +1318,8 @@ 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; @@ -1343,10 +1345,10 @@ static int event_enable_register_trigger(char *glob, 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; @@ -1356,6 +1358,8 @@ 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); @@ -1375,8 +1379,12 @@ 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; @@ -1447,6 +1455,7 @@ __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;