diff options
Diffstat (limited to 'kernel/trace/trace_events_hist.c')
| -rw-r--r-- | kernel/trace/trace_events_hist.c | 183 |
1 files changed, 135 insertions, 48 deletions
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index 9c058aa8baf3..1260c23cfa5f 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -5311,6 +5311,8 @@ static void event_hist_trigger(struct event_trigger_data *data, if (resolve_var_refs(hist_data, key, var_ref_vals, true)) hist_trigger_actions(hist_data, elt, buffer, rec, rbe, key, var_ref_vals); + + hist_poll_wakeup(); } static void hist_trigger_stacktrace_print(struct seq_file *m, @@ -5590,49 +5592,137 @@ static void hist_trigger_show(struct seq_file *m, n_entries, (u64)atomic64_read(&hist_data->map->drops)); } +struct hist_file_data { + struct file *file; + u64 last_read; + u64 last_act; +}; + +static u64 get_hist_hit_count(struct trace_event_file *event_file) +{ + struct hist_trigger_data *hist_data; + struct event_trigger_data *data; + u64 ret = 0; + + list_for_each_entry(data, &event_file->triggers, list) { + if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) { + hist_data = data->private_data; + ret += atomic64_read(&hist_data->map->hits); + } + } + return ret; +} + static int hist_show(struct seq_file *m, void *v) { + struct hist_file_data *hist_file = m->private; struct event_trigger_data *data; struct trace_event_file *event_file; - int n = 0, ret = 0; + int n = 0; - mutex_lock(&event_mutex); + guard(mutex)(&event_mutex); - event_file = event_file_file(m->private); - if (unlikely(!event_file)) { - ret = -ENODEV; - goto out_unlock; - } + event_file = event_file_file(hist_file->file); + if (unlikely(!event_file)) + return -ENODEV; list_for_each_entry(data, &event_file->triggers, list) { if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) hist_trigger_show(m, data, n++); } + hist_file->last_read = get_hist_hit_count(event_file); + /* + * Update last_act too so that poll()/POLLPRI can wait for the next + * event after any syscall on hist file. + */ + hist_file->last_act = hist_file->last_read; - out_unlock: - mutex_unlock(&event_mutex); + return 0; +} + +static __poll_t event_hist_poll(struct file *file, struct poll_table_struct *wait) +{ + struct trace_event_file *event_file; + struct seq_file *m = file->private_data; + struct hist_file_data *hist_file = m->private; + __poll_t ret = 0; + u64 cnt; + + guard(mutex)(&event_mutex); + + event_file = event_file_data(file); + if (!event_file) + return EPOLLERR; + + hist_poll_wait(file, wait); + + cnt = get_hist_hit_count(event_file); + if (hist_file->last_read != cnt) + ret |= EPOLLIN | EPOLLRDNORM; + if (hist_file->last_act != cnt) { + hist_file->last_act = cnt; + ret |= EPOLLPRI; + } return ret; } +static int event_hist_release(struct inode *inode, struct file *file) +{ + struct seq_file *m = file->private_data; + struct hist_file_data *hist_file = m->private; + + kfree(hist_file); + return tracing_single_release_file_tr(inode, file); +} + static int event_hist_open(struct inode *inode, struct file *file) { + struct trace_event_file *event_file; + struct hist_file_data *hist_file; int ret; ret = tracing_open_file_tr(inode, file); if (ret) return ret; + guard(mutex)(&event_mutex); + + event_file = event_file_data(file); + if (!event_file) { + ret = -ENODEV; + goto err; + } + + hist_file = kzalloc(sizeof(*hist_file), GFP_KERNEL); + if (!hist_file) { + ret = -ENOMEM; + goto err; + } + + hist_file->file = file; + hist_file->last_act = get_hist_hit_count(event_file); + /* Clear private_data to avoid warning in single_open() */ file->private_data = NULL; - return single_open(file, hist_show, file); + ret = single_open(file, hist_show, hist_file); + if (ret) { + kfree(hist_file); + goto err; + } + + return 0; +err: + tracing_release_file_tr(inode, file); + return ret; } const struct file_operations event_hist_fops = { .open = event_hist_open, .read = seq_read, .llseek = seq_lseek, - .release = tracing_single_release_file_tr, + .release = event_hist_release, + .poll = event_hist_poll, }; #ifdef CONFIG_HIST_TRIGGERS_DEBUG @@ -5873,25 +5963,19 @@ static int hist_debug_show(struct seq_file *m, void *v) { struct event_trigger_data *data; struct trace_event_file *event_file; - int n = 0, ret = 0; + int n = 0; - mutex_lock(&event_mutex); + guard(mutex)(&event_mutex); event_file = event_file_file(m->private); - if (unlikely(!event_file)) { - ret = -ENODEV; - goto out_unlock; - } + if (unlikely(!event_file)) + return -ENODEV; list_for_each_entry(data, &event_file->triggers, list) { if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) hist_trigger_debug_show(m, data, n++); } - - out_unlock: - mutex_unlock(&event_mutex); - - return ret; + return 0; } static int event_hist_debug_open(struct inode *inode, struct file *file) @@ -5904,7 +5988,10 @@ static int event_hist_debug_open(struct inode *inode, struct file *file) /* Clear private_data to avoid warning in single_open() */ file->private_data = NULL; - return single_open(file, hist_debug_show, file); + ret = single_open(file, hist_debug_show, file); + if (ret) + tracing_release_file_tr(inode, file); + return ret; } const struct file_operations event_hist_debug_fops = { @@ -6116,7 +6203,7 @@ static void event_hist_trigger_free(struct event_trigger_data *data) } } -static struct event_trigger_ops event_hist_trigger_ops = { +static const struct event_trigger_ops event_hist_trigger_ops = { .trigger = event_hist_trigger, .print = event_hist_trigger_print, .init = event_hist_trigger_init, @@ -6148,15 +6235,15 @@ static void event_hist_trigger_named_free(struct event_trigger_data *data) } } -static struct event_trigger_ops event_hist_trigger_named_ops = { +static const struct event_trigger_ops event_hist_trigger_named_ops = { .trigger = event_hist_trigger, .print = event_hist_trigger_print, .init = event_hist_trigger_named_init, .free = event_hist_trigger_named_free, }; -static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd, - char *param) +static const struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd, + char *param) { return &event_hist_trigger_ops; } @@ -6649,27 +6736,27 @@ static int event_hist_trigger_parse(struct event_command *cmd_ops, if (existing_hist_update_only(glob, trigger_data, file)) goto out_free; - ret = event_trigger_register(cmd_ops, file, glob, trigger_data); - if (ret < 0) - goto out_free; + if (!get_named_trigger_data(trigger_data)) { - if (get_named_trigger_data(trigger_data)) - goto enable; + ret = create_actions(hist_data); + if (ret) + goto out_free; - ret = create_actions(hist_data); - if (ret) - goto out_unreg; + if (has_hist_vars(hist_data) || hist_data->n_var_refs) { + ret = save_hist_vars(hist_data); + if (ret) + goto out_free; + } - if (has_hist_vars(hist_data) || hist_data->n_var_refs) { - ret = save_hist_vars(hist_data); + ret = tracing_map_init(hist_data->map); if (ret) - goto out_unreg; + goto out_free; } - ret = tracing_map_init(hist_data->map); - if (ret) - goto out_unreg; -enable: + ret = event_trigger_register(cmd_ops, file, glob, trigger_data); + if (ret < 0) + goto out_free; + ret = hist_trigger_enable(trigger_data, file); if (ret) goto out_unreg; @@ -6751,38 +6838,38 @@ hist_enable_count_trigger(struct event_trigger_data *data, hist_enable_trigger(data, buffer, rec, event); } -static struct event_trigger_ops hist_enable_trigger_ops = { +static const struct event_trigger_ops hist_enable_trigger_ops = { .trigger = 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 = { +static const struct event_trigger_ops hist_enable_count_trigger_ops = { .trigger = 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 = { +static const struct event_trigger_ops hist_disable_trigger_ops = { .trigger = 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 = { +static const struct event_trigger_ops hist_disable_count_trigger_ops = { .trigger = hist_enable_count_trigger, .print = event_enable_trigger_print, .init = event_trigger_init, .free = event_enable_trigger_free, }; -static struct event_trigger_ops * +static const struct event_trigger_ops * hist_enable_get_trigger_ops(char *cmd, char *param) { - struct event_trigger_ops *ops; + const struct event_trigger_ops *ops; bool enable; enable = (strcmp(cmd, ENABLE_HIST_STR) == 0); |