From 7276531d4036f5db2af15c8b6caa02e7741f5d80 Mon Sep 17 00:00:00 2001 From: Tom Zanussi Date: Mon, 10 Feb 2020 17:06:50 -0600 Subject: tracing: Consolidate trace() functions Move the checking, buffer reserve and buffer commit code in synth_event_trace_start/end() into inline functions __synth_event_trace_start/end() so they can also be used by synth_event_trace() and synth_event_trace_array(), and then have all those functions use them. Also, change synth_event_trace_state.enabled to disabled so it only needs to be set if the event is disabled, which is not normally the case. Link: http://lkml.kernel.org/r/b1f3108d0f450e58192955a300e31d0405ab4149.1581374549.git.zanussi@kernel.org Signed-off-by: Tom Zanussi Signed-off-by: Steven Rostedt (VMware) --- include/linux/trace_events.h | 2 +- kernel/trace/trace_events_hist.c | 220 +++++++++++++++------------------------ 2 files changed, 87 insertions(+), 135 deletions(-) diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h index 67f528ecb9e5..21098298b49b 100644 --- a/include/linux/trace_events.h +++ b/include/linux/trace_events.h @@ -424,7 +424,7 @@ struct synth_event_trace_state { struct synth_event *event; unsigned int cur_field; unsigned int n_u64; - bool enabled; + bool disabled; bool add_next; bool add_name; }; diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index 99a02168599b..65b54d6a1422 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -1791,6 +1791,60 @@ void synth_event_cmd_init(struct dynevent_cmd *cmd, char *buf, int maxlen) } EXPORT_SYMBOL_GPL(synth_event_cmd_init); +static inline int +__synth_event_trace_start(struct trace_event_file *file, + struct synth_event_trace_state *trace_state) +{ + int entry_size, fields_size = 0; + int ret = 0; + + /* + * Normal event tracing doesn't get called at all unless the + * ENABLED bit is set (which attaches the probe thus allowing + * this code to be called, etc). Because this is called + * directly by the user, we don't have that but we still need + * to honor not logging when disabled. For the the iterated + * trace case, we save the enabed state upon start and just + * ignore the following data calls. + */ + if (!(file->flags & EVENT_FILE_FL_ENABLED) || + trace_trigger_soft_disabled(file)) { + trace_state->disabled = true; + ret = -ENOENT; + goto out; + } + + trace_state->event = file->event_call->data; + + fields_size = trace_state->event->n_u64 * sizeof(u64); + + /* + * Avoid ring buffer recursion detection, as this event + * is being performed within another event. + */ + trace_state->buffer = file->tr->array_buffer.buffer; + ring_buffer_nest_start(trace_state->buffer); + + entry_size = sizeof(*trace_state->entry) + fields_size; + trace_state->entry = trace_event_buffer_reserve(&trace_state->fbuffer, + file, + entry_size); + if (!trace_state->entry) { + ring_buffer_nest_end(trace_state->buffer); + ret = -EINVAL; + } +out: + return ret; +} + +static inline void +__synth_event_trace_end(struct synth_event_trace_state *trace_state) +{ + trace_event_buffer_commit(&trace_state->fbuffer); + + ring_buffer_nest_end(trace_state->buffer); +} + /** * synth_event_trace - Trace a synthetic event * @file: The trace_event_file representing the synthetic event @@ -1812,69 +1866,38 @@ EXPORT_SYMBOL_GPL(synth_event_cmd_init); */ int synth_event_trace(struct trace_event_file *file, unsigned int n_vals, ...) { - struct trace_event_buffer fbuffer; - struct synth_trace_event *entry; - struct trace_buffer *buffer; - struct synth_event *event; + struct synth_event_trace_state state; unsigned int i, n_u64; - int fields_size = 0; va_list args; - int ret = 0; - - /* - * Normal event generation doesn't get called at all unless - * the ENABLED bit is set (which attaches the probe thus - * allowing this code to be called, etc). Because this is - * called directly by the user, we don't have that but we - * still need to honor not logging when disabled. - */ - if (!(file->flags & EVENT_FILE_FL_ENABLED) || - trace_trigger_soft_disabled(file)) - return 0; - - event = file->event_call->data; - - if (n_vals != event->n_fields) - return -EINVAL; - - fields_size = event->n_u64 * sizeof(u64); - - /* - * Avoid ring buffer recursion detection, as this event - * is being performed within another event. - */ - buffer = file->tr->array_buffer.buffer; - ring_buffer_nest_start(buffer); + int ret; - entry = trace_event_buffer_reserve(&fbuffer, file, - sizeof(*entry) + fields_size); - if (!entry) { - ret = -EINVAL; - goto out; + ret = __synth_event_trace_start(file, &state); + if (ret) { + if (ret == -ENOENT) + ret = 0; /* just disabled, not really an error */ + return ret; } va_start(args, n_vals); - for (i = 0, n_u64 = 0; i < event->n_fields; i++) { + for (i = 0, n_u64 = 0; i < state.event->n_fields; i++) { u64 val; val = va_arg(args, u64); - if (event->fields[i]->is_string) { + if (state.event->fields[i]->is_string) { char *str_val = (char *)(long)val; - char *str_field = (char *)&entry->fields[n_u64]; + char *str_field = (char *)&state.entry->fields[n_u64]; strscpy(str_field, str_val, STR_VAR_LEN_MAX); n_u64 += STR_VAR_LEN_MAX / sizeof(u64); } else { - entry->fields[n_u64] = val; + state.entry->fields[n_u64] = val; n_u64++; } } va_end(args); - trace_event_buffer_commit(&fbuffer); -out: - ring_buffer_nest_end(buffer); + __synth_event_trace_end(&state); return ret; } @@ -1901,62 +1924,31 @@ EXPORT_SYMBOL_GPL(synth_event_trace); int synth_event_trace_array(struct trace_event_file *file, u64 *vals, unsigned int n_vals) { - struct trace_event_buffer fbuffer; - struct synth_trace_event *entry; - struct trace_buffer *buffer; - struct synth_event *event; + struct synth_event_trace_state state; unsigned int i, n_u64; - int fields_size = 0; - int ret = 0; - - /* - * Normal event generation doesn't get called at all unless - * the ENABLED bit is set (which attaches the probe thus - * allowing this code to be called, etc). Because this is - * called directly by the user, we don't have that but we - * still need to honor not logging when disabled. - */ - if (!(file->flags & EVENT_FILE_FL_ENABLED) || - trace_trigger_soft_disabled(file)) - return 0; - - event = file->event_call->data; - - if (n_vals != event->n_fields) - return -EINVAL; - - fields_size = event->n_u64 * sizeof(u64); - - /* - * Avoid ring buffer recursion detection, as this event - * is being performed within another event. - */ - buffer = file->tr->array_buffer.buffer; - ring_buffer_nest_start(buffer); + int ret; - entry = trace_event_buffer_reserve(&fbuffer, file, - sizeof(*entry) + fields_size); - if (!entry) { - ret = -EINVAL; - goto out; + ret = __synth_event_trace_start(file, &state); + if (ret) { + if (ret == -ENOENT) + ret = 0; /* just disabled, not really an error */ + return ret; } - for (i = 0, n_u64 = 0; i < event->n_fields; i++) { - if (event->fields[i]->is_string) { + for (i = 0, n_u64 = 0; i < state.event->n_fields; i++) { + if (state.event->fields[i]->is_string) { char *str_val = (char *)(long)vals[i]; - char *str_field = (char *)&entry->fields[n_u64]; + char *str_field = (char *)&state.entry->fields[n_u64]; strscpy(str_field, str_val, STR_VAR_LEN_MAX); n_u64 += STR_VAR_LEN_MAX / sizeof(u64); } else { - entry->fields[n_u64] = vals[i]; + state.entry->fields[n_u64] = vals[i]; n_u64++; } } - trace_event_buffer_commit(&fbuffer); -out: - ring_buffer_nest_end(buffer); + __synth_event_trace_end(&state); return ret; } @@ -1993,55 +1985,17 @@ EXPORT_SYMBOL_GPL(synth_event_trace_array); int synth_event_trace_start(struct trace_event_file *file, struct synth_event_trace_state *trace_state) { - struct synth_trace_event *entry; - int fields_size = 0; - int ret = 0; + int ret; - if (!trace_state) { - ret = -EINVAL; - goto out; - } + if (!trace_state) + return -EINVAL; memset(trace_state, '\0', sizeof(*trace_state)); - /* - * Normal event tracing doesn't get called at all unless the - * ENABLED bit is set (which attaches the probe thus allowing - * this code to be called, etc). Because this is called - * directly by the user, we don't have that but we still need - * to honor not logging when disabled. For the the iterated - * trace case, we save the enabed state upon start and just - * ignore the following data calls. - */ - if (!(file->flags & EVENT_FILE_FL_ENABLED) || - trace_trigger_soft_disabled(file)) { - trace_state->enabled = false; - goto out; - } - - trace_state->enabled = true; + ret = __synth_event_trace_start(file, trace_state); + if (ret == -ENOENT) + ret = 0; /* just disabled, not really an error */ - trace_state->event = file->event_call->data; - - fields_size = trace_state->event->n_u64 * sizeof(u64); - - /* - * Avoid ring buffer recursion detection, as this event - * is being performed within another event. - */ - trace_state->buffer = file->tr->array_buffer.buffer; - ring_buffer_nest_start(trace_state->buffer); - - entry = trace_event_buffer_reserve(&trace_state->fbuffer, file, - sizeof(*entry) + fields_size); - if (!entry) { - ring_buffer_nest_end(trace_state->buffer); - ret = -EINVAL; - goto out; - } - - trace_state->entry = entry; -out: return ret; } EXPORT_SYMBOL_GPL(synth_event_trace_start); @@ -2074,7 +2028,7 @@ static int __synth_event_add_val(const char *field_name, u64 val, trace_state->add_next = true; } - if (!trace_state->enabled) + if (trace_state->disabled) goto out; event = trace_state->event; @@ -2209,9 +2163,7 @@ int synth_event_trace_end(struct synth_event_trace_state *trace_state) if (!trace_state) return -EINVAL; - trace_event_buffer_commit(&trace_state->fbuffer); - - ring_buffer_nest_end(trace_state->buffer); + __synth_event_trace_end(trace_state); return 0; } -- cgit v1.2.3