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

Tanish Desai posted 2 patches 4 months, 1 week ago
Maintainers: Stefan Hajnoczi <stefanha@redhat.com>, Mads Ynddal <mads@ynddal.dk>
[PATCH v2 2/2] tracetool/format: remove redundent trace-event checks
Posted by Tanish Desai 4 months, 1 week ago 
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;',
         '#line %(event_lineno)d "%(event_filename)s"',
         '            trlen = snprintf(ftrace_buf, MAX_TRACE_STRLEN,',
         '                             "%(name)s " %(fmt)s "\\n" %(argnames)s);',
@@ -40,10 +40,8 @@ def generate_h(event, group):
         '            trlen = MIN(trlen, MAX_TRACE_STRLEN - 1);',
         '            unused = write(trace_marker_fd, ftrace_buf, trlen);',
         '        }',
-        '    }',
         name=event.name,
         args=event.args,
-        event_id="TRACE_" + event.name.upper(),
         event_lineno=event.lineno,
         event_filename=event.filename,
         fmt=event.fmt.rstrip("\n"),
diff --git a/scripts/tracetool/backend/log.py b/scripts/tracetool/backend/log.py
index eb50ceea34..2aa180f4b4 100644
--- a/scripts/tracetool/backend/log.py
+++ b/scripts/tracetool/backend/log.py
@@ -16,6 +16,7 @@
 
 
 PUBLIC = True
+CHECK_TRACE_EVENT_GET_STATE = True
 
 
 def generate_h_begin(events, group):
@@ -28,14 +29,11 @@ def generate_h(event, group):
     if len(event.args) > 0:
         argnames = ", " + argnames
 
-    cond = "trace_event_get_state(%s)" % ("TRACE_" + event.name.upper())
-
-    out('    if (%(cond)s && qemu_loglevel_mask(LOG_TRACE)) {',
+    out('        if (qemu_loglevel_mask(LOG_TRACE)) {',
         '#line %(event_lineno)d "%(event_filename)s"',
-        '        qemu_log("%(name)s " %(fmt)s "\\n"%(argnames)s);',
+        '            qemu_log("%(name)s " %(fmt)s "\\n"%(argnames)s);',
         '#line %(out_next_lineno)d "%(out_filename)s"',
-        '    }',
-        cond=cond,
+        '        }',
         event_lineno=event.lineno,
         event_filename=event.filename,
         name=event.name,
diff --git a/scripts/tracetool/backend/simple.py b/scripts/tracetool/backend/simple.py
index 7c84c06b20..623ea7d8ed 100644
--- a/scripts/tracetool/backend/simple.py
+++ b/scripts/tracetool/backend/simple.py
@@ -16,7 +16,7 @@
 
 
 PUBLIC = True
-
+CHECK_TRACE_EVENT_GET_STATE = True
 
 def is_string(arg):
     strtype = ('const char*', 'char*', 'const char *', 'char *')
@@ -36,13 +36,8 @@ def generate_h_begin(events, group):
 
 
 def generate_h(event, group):
-    event_id = 'TRACE_' + event.name.upper()
-    cond = "trace_event_get_state(%s)" % event_id
-    out('    if (%(cond)s) {',
-        '        _simple_%(api)s(%(args)s);',
-        '    }',
+    out('        _simple_%(api)s(%(args)s);',
         api=event.api(),
-        cond=cond,
         args=", ".join(event.args.names()))
 
 
diff --git a/scripts/tracetool/backend/syslog.py b/scripts/tracetool/backend/syslog.py
index 3f82e54aab..04ec85717a 100644
--- a/scripts/tracetool/backend/syslog.py
+++ b/scripts/tracetool/backend/syslog.py
@@ -16,6 +16,7 @@
 
 
 PUBLIC = True
+CHECK_TRACE_EVENT_GET_STATE = True
 
 
 def generate_h_begin(events, group):
@@ -28,14 +29,9 @@ def generate_h(event, group):
     if len(event.args) > 0:
         argnames = ", " + argnames
 
-    cond = "trace_event_get_state(%s)" % ("TRACE_" + event.name.upper())
-
-    out('    if (%(cond)s) {',
-        '#line %(event_lineno)d "%(event_filename)s"',
+    out('#line %(event_lineno)d "%(event_filename)s"',
         '        syslog(LOG_INFO, "%(name)s " %(fmt)s %(argnames)s);',
         '#line %(out_next_lineno)d "%(out_filename)s"',
-        '    }',
-        cond=cond,
         event_lineno=event.lineno,
         event_filename=event.filename,
         name=event.name,
-- 
2.34.1
Re: [PATCH v2 2/2] tracetool/format: remove redundent trace-event checks
Posted by Stefan Hajnoczi 4 months, 1 week ago 
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(-)

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Re: [PATCH v2 2/2] tracetool/format: remove redundent trace-event checks
Posted by Daniel P. Berrangé 4 months, 1 week ago 
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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Patchew 2.1-devel-b67e4c2

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