perf jevents: Simplify generation of C-string

Previous implementation wanted variable order and '(null)' string output
to match the C implementation. The '(null)' string output was a
quirk/bug and so there is no need to carry it forward.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.garry@huawei.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Will Deacon <will@kernel.org>
Cc: Xing Zhengjun <zhengjun.xing@linux.intel.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lore.kernel.org/lkml/20220804221816.1802790-3-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/pmu-events/jevents.py b/tools/perf/pmu-events/jevents.py
index 5b72048..cdfa4e0 100755 (executable)
--- a/tools/perf/pmu-events/jevents.py
+++ b/tools/perf/pmu-events/jevents.py
@@ -203,7 +203,7 @@ class JsonEvent:
     """Representation of the event as a C struct initializer."""
 
     def attr_string(attr: str, value: str) -> str:
-      return '\t.%s = \"%s\",\n' % (attr, value)
+      return f'\t.{attr} = \"{value}\",\n'
 
     def str_if_present(self, attr: str) -> str:
       if not getattr(self, attr):
@@ -211,17 +211,11 @@ class JsonEvent:
       return attr_string(attr, getattr(self, attr))
 
     s = '{\n'
-    for attr in ['name', 'event']:
-      s += str_if_present(self, attr)
-    if self.desc is not None:
-      s += attr_string('desc', self.desc)
-    else:
-      s += attr_string('desc', '(null)')
-    s += str_if_present(self, 'compat')
     s += f'\t.topic = "{topic_local}",\n'
     for attr in [
-        'long_desc', 'pmu', 'unit', 'perpkg', 'aggr_mode', 'metric_expr',
-        'metric_name', 'metric_group', 'deprecated', 'metric_constraint'
+        'aggr_mode', 'compat', 'deprecated', 'desc', 'event', 'long_desc',
+        'metric_constraint', 'metric_expr', 'metric_group', 'metric_name',
+        'name', 'perpkg', 'pmu', 'unit'
     ]:
       s += str_if_present(self, attr)
     s += '},\n'