Re: [PATCH v2 2/2] tracetool/format: remove redundent trace-event checks

["Daniel P. Berrangé" <berrange@redhat.com>]

On Wed, Aug 06, 2025 at 03:05:39PM +0000, Tanish Desai wrote:
> Remove redundent if(check_trace_event) check
> from individual backends.
> Adding CHECK_TRACE_EVENT_GET_STATE in log,syslog,
> dtrace and simple backend.
> 
> Signed-off-by: Tanish Desai <tanishdesai37@gmail.com>
> ---
>  scripts/tracetool/backend/ftrace.py | 12 +++++-------
>  scripts/tracetool/backend/log.py    | 10 ++++------
>  scripts/tracetool/backend/simple.py |  9 ++-------
>  scripts/tracetool/backend/syslog.py |  8 ++------
>  4 files changed, 13 insertions(+), 26 deletions(-)
> 
> diff --git a/scripts/tracetool/backend/ftrace.py b/scripts/tracetool/backend/ftrace.py
> index 5fa30ccc08..c65d3b89b3 100644
> --- a/scripts/tracetool/backend/ftrace.py
> +++ b/scripts/tracetool/backend/ftrace.py
> @@ -16,6 +16,7 @@
>  
>  
>  PUBLIC = True
> +CHECK_TRACE_EVENT_GET_STATE = True
>  
>  
>  def generate_h_begin(events, group):
> @@ -28,11 +29,10 @@ def generate_h(event, group):
>      if len(event.args) > 0:
>          argnames = ", " + argnames
>  
> -    out('    {',
> -        '        char ftrace_buf[MAX_TRACE_STRLEN];',
> -        '        int unused __attribute__ ((unused));',
> -        '        int trlen;',
> -        '        if (trace_event_get_state(%(event_id)s)) {',
> +    out('        {',
> +        '            char ftrace_buf[MAX_TRACE_STRLEN];',
> +        '            int unused __attribute__ ((unused));',
> +        '            int trlen;',

This results in unecessary nested code blocks & indent.
For example:

static inline void trace_test_blah(void *context, const char *filename)
{
    if (trace_event_get_state(TRACE_TEST_BLAH)) {
        {
            char ftrace_buf[MAX_TRACE_STRLEN];
            int unused __attribute__ ((unused));
            int trlen;
#line 4 "trace-events"
            trlen = snprintf(ftrace_buf, MAX_TRACE_STRLEN,
                             "test_blah " "Blah context=%p filename=%s" "\n" , context, filename);
#line 33 "[stdout]"
            trlen = MIN(trlen, MAX_TRACE_STRLEN - 1);
            unused = write(trace_marker_fd, ftrace_buf, trlen);
        }
    }
}

Instead of


static inline void trace_test_blah(void *context, const char *filename)
{
    if (trace_event_get_state(TRACE_TEST_BLAH)) {
        char ftrace_buf[MAX_TRACE_STRLEN];
        int unused __attribute__ ((unused));
        int trlen;
#line 4 "trace-events"
        trlen = snprintf(ftrace_buf, MAX_TRACE_STRLEN,
                         "test_blah " "Blah context=%p filename=%s" "\n" , context, filename);
#line 33 "[stdout]"
        trlen = MIN(trlen, MAX_TRACE_STRLEN - 1);
        unused = write(trace_marker_fd, ftrace_buf, trlen);
    }
}



With regards,
Daniel
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