Re: [PATCH 04/11] trace-cmd: add global functions for live tracing

[Josef Bacik]

Yup go for it, thanks,

Josef

Sent from my iPhone

> On Jul 9, 2019, at 9:09 AM, Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:
> 
> On Fri, 20 Nov 2015 15:57:26 -0500
> Josef Bacik <jbacik@xxxxxx> wrote:
> 
>> We need a few functions to disable/enable tracing as well as add events to be
>> enabled on the first instance, this patch turns a couple of these local
>> functions into library functions.  Thanks,
> 
> Hi Josef,
> 
> Not sure you still use this, as it's not really a library function
> anymore. But we are currently cleaning up the trace-cmd code to create
> a real library, and doing it in baby steps. The
> tracecmd_enable_events() function is causing some issues and it was
> added by you. Are you OK if we remove it. At least temporarily until we
> separate out the "enabling" part into the library?
> 
> Thanks!
> 
> -- Steve
> 
> 
>> 
>> Signed-off-by: Josef Bacik <jbacik@xxxxxx>
>> ---
>> trace-cmd.h    |  5 +++++
>> trace-record.c | 45 +++++++++++++++++++++++++++------------------
>> 2 files changed, 32 insertions(+), 18 deletions(-)
>> 
>> diff --git a/trace-cmd.h b/trace-cmd.h
>> index b4fa7fd..9a9ca30 100644
>> --- a/trace-cmd.h
>> +++ b/trace-cmd.h
>> @@ -268,6 +268,11 @@ int tracecmd_start_recording(struct tracecmd_recorder *recorder, unsigned long s
>> void tracecmd_stop_recording(struct tracecmd_recorder *recorder);
>> void tracecmd_stat_cpu(struct trace_seq *s, int cpu);
>> long tracecmd_flush_recording(struct tracecmd_recorder *recorder);
>> +int tracecmd_add_event(const char *event_str, int stack);
>> +void tracecmd_enable_events(void);
>> +void tracecmd_disable_all_tracing(int disable_tracer);
>> +void tracecmd_disable_tracing(void);
>> +void tracecmd_enable_tracing(void);
>> 
>> /* --- Plugin handling --- */
>> extern struct pevent_plugin_option trace_ftrace_options[];
>> diff --git a/trace-record.c b/trace-record.c
>> index 417b701..7c471ab 100644
>> --- a/trace-record.c
>> +++ b/trace-record.c
>> @@ -841,7 +841,6 @@ static void update_ftrace_pids(int reset)
>> 
>> static void update_event_filters(struct buffer_instance *instance);
>> static void update_pid_event_filters(struct buffer_instance *instance);
>> -static void enable_tracing(void);
>> 
>> /**
>>  * make_pid_filter - create a filter string to all pids against @field
>> @@ -1106,7 +1105,7 @@ static void run_cmd(enum trace_type type, int argc, char **argv)
>>    if (!pid) {
>>        /* child */
>>        update_task_filter();
>> -        enable_tracing();
>> +        tracecmd_enable_tracing();
>>        enable_ptrace();
>>        /*
>>         * If we are using stderr for stdout, switch
>> @@ -1795,7 +1794,7 @@ static int read_tracing_on(struct buffer_instance *instance)
>>    return ret;
>> }
>> 
>> -static void enable_tracing(void)
>> +void tracecmd_enable_tracing(void)
>> {
>>    struct buffer_instance *instance;
>> 
>> @@ -1808,7 +1807,7 @@ static void enable_tracing(void)
>>        reset_max_latency();
>> }
>> 
>> -static void disable_tracing(void)
>> +void tracecmd_disable_tracing(void)
>> {
>>    struct buffer_instance *instance;
>> 
>> @@ -1816,9 +1815,9 @@ static void disable_tracing(void)
>>        write_tracing_on(instance, 0);
>> }
>> 
>> -static void disable_all(int disable_tracer)
>> +void tracecmd_disable_all_tracing(int disable_tracer)
>> {
>> -    disable_tracing();
>> +    tracecmd_disable_tracing();
>> 
>>    if (disable_tracer) {
>>        disable_func_stack_trace();
>> @@ -1991,6 +1990,11 @@ static void enable_events(struct buffer_instance *instance)
>>    }
>> }
>> 
>> +void tracecmd_enable_events(void)
>> +{
>> +    enable_events(first_instance);
>> +}
>> +
>> static void set_clock(struct buffer_instance *instance)
>> {
>>    char *path;
>> @@ -3074,15 +3078,15 @@ static char *get_date_to_ts(void)
>>    }
>> 
>>    for (i = 0; i < date2ts_tries; i++) {
>> -        disable_tracing();
>> +        tracecmd_disable_tracing();
>>        clear_trace();
>> -        enable_tracing();
>> +        tracecmd_enable_tracing();
>> 
>>        gettimeofday(&start, NULL);
>>        write(tfd, STAMP, 5);
>>        gettimeofday(&end, NULL);
>> 
>> -        disable_tracing();
>> +        tracecmd_disable_tracing();
>>        ts = find_time_stamp(pevent);
>>        if (!ts)
>>            continue;
>> @@ -3699,6 +3703,11 @@ profile_add_event(struct buffer_instance *instance, const char *event_str, int s
>>    return 0;
>> }
>> 
>> +int tracecmd_add_event(const char *event_str, int stack)
>> +{
>> +    return profile_add_event(first_instance, event_str, stack);
>> +}
>> +
>> static void enable_profile(struct buffer_instance *instance)
>> {
>>    int stacktrace = 0;
>> @@ -3891,7 +3900,7 @@ void trace_record (int argc, char **argv)
>> 
>>        }
>>        update_first_instance(instance, topt);
>> -        disable_tracing();
>> +        tracecmd_disable_tracing();
>>        exit(0);
>>    } else if (strcmp(argv[1], "restart") == 0) {
>>        for (;;) {
>> @@ -3922,7 +3931,7 @@ void trace_record (int argc, char **argv)
>> 
>>        }
>>        update_first_instance(instance, topt);
>> -        enable_tracing();
>> +        tracecmd_enable_tracing();
>>        exit(0);
>>    } else if (strcmp(argv[1], "reset") == 0) {
>>        /* if last arg is -a, then -b and -d apply to all instances */
>> @@ -3984,7 +3993,7 @@ void trace_record (int argc, char **argv)
>>            }
>>        }
>>        update_first_instance(instance, topt);
>> -        disable_all(1);
>> +        tracecmd_disable_all_tracing(1);
>>        set_buffer_size();
>>        clear_filters();
>>        clear_triggers();
>> @@ -4314,7 +4323,7 @@ void trace_record (int argc, char **argv)
>> 
>>    if (!extract) {
>>        fset = set_ftrace(!disable, total_disable);
>> -        disable_all(1);
>> +        tracecmd_disable_all_tracing(1);
>> 
>>        for_all_instances(instance)
>>            set_clock(instance);
>> @@ -4365,7 +4374,7 @@ void trace_record (int argc, char **argv)
>>    } else {
>>        if (!(type & (TRACE_TYPE_RECORD | TRACE_TYPE_STREAM))) {
>>            update_task_filter();
>> -            enable_tracing();
>> +            tracecmd_enable_tracing();
>>            exit(0);
>>        }
>> 
>> @@ -4373,7 +4382,7 @@ void trace_record (int argc, char **argv)
>>            run_cmd(type, (argc - optind) - 1, &argv[optind + 1]);
>>        else {
>>            update_task_filter();
>> -            enable_tracing();
>> +            tracecmd_enable_tracing();
>>            /* We don't ptrace ourself */
>>            if (do_ptrace && filter_pid >= 0)
>>                ptrace_attach(filter_pid);
>> @@ -4383,7 +4392,7 @@ void trace_record (int argc, char **argv)
>>                trace_or_sleep(type);
>>        }
>> 
>> -        disable_tracing();
>> +        tracecmd_disable_tracing();
>>        if (!latency)
>>            stop_threads(type);
>>    }
>> @@ -4391,7 +4400,7 @@ void trace_record (int argc, char **argv)
>>    record_stats();
>> 
>>    if (!keep)
>> -        disable_all(0);
>> +        tracecmd_disable_all_tracing(0);
>> 
>>    /* extract records the date after extraction */
>>    if (extract && date) {
>> @@ -4399,7 +4408,7 @@ void trace_record (int argc, char **argv)
>>         * We need to start tracing, don't let other traces
>>         * screw with our trace_marker.
>>         */
>> -        disable_all(1);
>> +        tracecmd_disable_all_tracing(1);
>>        date2ts = get_date_to_ts();
>>    }
>> 
>