diff options
Diffstat (limited to 'tools/tracing/rtla/src/trace.c')
| -rw-r--r-- | tools/tracing/rtla/src/trace.c | 69 |
1 files changed, 50 insertions, 19 deletions
diff --git a/tools/tracing/rtla/src/trace.c b/tools/tracing/rtla/src/trace.c index 170a706248ab..69cbc48d53d3 100644 --- a/tools/tracing/rtla/src/trace.c +++ b/tools/tracing/rtla/src/trace.c @@ -75,12 +75,16 @@ int save_trace_to_file(struct tracefs_instance *inst, const char *filename) int out_fd, in_fd; int retval = -1; + if (!inst || !filename) + return 0; + in_fd = tracefs_instance_file_open(inst, file, O_RDONLY); if (in_fd < 0) { err_msg("Failed to open trace file\n"); return -1; } + printf(" Saving trace to %s\n", filename); out_fd = creat(filename, mode); if (out_fd < 0) { err_msg("Failed to create output file %s\n", filename); @@ -118,6 +122,8 @@ collect_registered_events(struct tep_event *event, struct tep_record *record, struct trace_instance *trace = context; struct trace_seq *s = trace->seq; + trace->processed_events++; + if (!event->handler) return 0; @@ -127,6 +133,31 @@ collect_registered_events(struct tep_event *event, struct tep_record *record, } /* + * collect_missed_events - record number of missed events + * + * If rtla cannot keep up with events generated by tracer, events are going + * to fall out of the ring buffer. + * Collect how many events were missed so it can be reported to the user. + */ +static int +collect_missed_events(struct tep_event *event, struct tep_record *record, + int cpu, void *context) +{ + struct trace_instance *trace = context; + + if (trace->missed_events == UINT64_MAX) + return 0; + + if (record->missed_events > 0) + trace->missed_events += record->missed_events; + else + /* Events missed but no data on how many */ + trace->missed_events = UINT64_MAX; + + return 0; +} + +/* * trace_instance_destroy - destroy and free a rtla trace instance */ void trace_instance_destroy(struct trace_instance *trace) @@ -181,6 +212,17 @@ int trace_instance_init(struct trace_instance *trace, char *tool_name) */ tracefs_trace_off(trace->inst); + /* + * Collect the number of events missed due to tracefs buffer + * overflow. + */ + trace->missed_events = 0; + tracefs_follow_missed_events(trace->inst, + collect_missed_events, + trace); + + trace->processed_events = 0; + return 0; out_err: @@ -197,6 +239,14 @@ int trace_instance_start(struct trace_instance *trace) } /* + * trace_instance_stop - stop tracing a given rtla instance + */ +int trace_instance_stop(struct trace_instance *trace) +{ + return tracefs_trace_off(trace->inst); +} + +/* * trace_events_free - free a list of trace events */ static void trace_events_free(struct trace_events *events) @@ -522,25 +572,6 @@ void trace_events_destroy(struct trace_instance *instance, trace_events_free(events); } -int trace_is_off(struct trace_instance *tool, struct trace_instance *trace) -{ - /* - * The tool instance is always present, it is the one used to collect - * data. - */ - if (!tracefs_trace_is_on(tool->inst)) - return 1; - - /* - * The trace instance is only enabled when -t is set. IOW, when the system - * is tracing. - */ - if (trace && !tracefs_trace_is_on(trace->inst)) - return 1; - - return 0; -} - /* * trace_set_buffer_size - set the per-cpu tracing buffer size. */ |