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

Tanish Desai posted 2 patches 3 months, 1 week ago
Maintainers: Stefan Hajnoczi <stefanha@redhat.com>, Mads Ynddal <mads@ynddal.dk>
There is a newer version of this series
[PATCH 2/2] tracetool/format: remove redundent trace-event checks
Posted by Tanish Desai 3 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 | 4 +---
 scripts/tracetool/backend/log.py    | 6 ++----
 scripts/tracetool/backend/simple.py | 9 ++-------
 scripts/tracetool/backend/syslog.py | 8 ++------
 4 files changed, 7 insertions(+), 20 deletions(-)

diff --git a/scripts/tracetool/backend/ftrace.py b/scripts/tracetool/backend/ftrace.py
index 5fa30ccc08..b38f527461 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):
@@ -32,18 +33,15 @@ def generate_h(event, group):
         '        char ftrace_buf[MAX_TRACE_STRLEN];',
         '        int unused __attribute__ ((unused));',
         '        int trlen;',
-        '        if (trace_event_get_state(%(event_id)s)) {',
         '#line %(event_lineno)d "%(event_filename)s"',
         '            trlen = snprintf(ftrace_buf, MAX_TRACE_STRLEN,',
         '                             "%(name)s " %(fmt)s "\\n" %(argnames)s);',
         '#line %(out_next_lineno)d "%(out_filename)s"',
         '            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..d8406d226b 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);',
         '#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 2/2] tracetool/format: remove redundent trace-event checks
Posted by Daniel P. Berrangé 3 months, 1 week ago 
On Mon, Aug 04, 2025 at 11:20:39AM +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 | 4 +---
>  scripts/tracetool/backend/log.py    | 6 ++----
>  scripts/tracetool/backend/simple.py | 9 ++-------
>  scripts/tracetool/backend/syslog.py | 8 ++------
>  4 files changed, 7 insertions(+), 20 deletions(-)
> 
> diff --git a/scripts/tracetool/backend/ftrace.py b/scripts/tracetool/backend/ftrace.py
> index 5fa30ccc08..b38f527461 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):
> @@ -32,18 +33,15 @@ def generate_h(event, group):
>          '        char ftrace_buf[MAX_TRACE_STRLEN];',
>          '        int unused __attribute__ ((unused));',
>          '        int trlen;',
> -        '        if (trace_event_get_state(%(event_id)s)) {',
>          '#line %(event_lineno)d "%(event_filename)s"',
>          '            trlen = snprintf(ftrace_buf, MAX_TRACE_STRLEN,',
>          '                             "%(name)s " %(fmt)s "\\n" %(argnames)s);',
>          '#line %(out_next_lineno)d "%(out_filename)s"',
>          '            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..d8406d226b 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);',
>          '#line %(out_next_lineno)d "%(out_filename)s"',
>          '    }',
> -        cond=cond,
>          event_lineno=event.lineno,
>          event_filename=event.filename,
>          name=event.name,

This change results in bad indentation of the generated inline function
nested if conditions. e.g. the result looks like this:

static inline void trace_test_blah(void *context, const char *filename)
{
    if (trace_event_get_state(TRACE_TEST_BLAH)) {
    if (qemu_loglevel_mask(LOG_TRACE)) {
#line 4 "trace-events"
        qemu_log("test_blah " "Blah context=%p filename=%s" "\n", context, filename);
#line 29 "../../../../../../../../dev/stdout"
    }
    }
}


With regards,
Daniel
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