tracing: Remove pid in task_rename tracing output

Remove pid in task_rename tracepoint output, since that tracepoint only
deals with the current task, and is printed by default. This also saves
some space in the entry and avoids wasted padding.

Link: https://lkml.kernel.org/r/20241105120247.596a0dc9@gandalf.local.home
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Marco Elver <elver@google.com>
Link: https://lore.kernel.org/r/20241108113455.2924361-2-elver@google.com
Signed-off-by: Kees Cook <kees@kernel.org>

include/trace/events/task.h

@@ -38,22 +38,19 @@ TRACE_EVENT(task_rename,
 	TP_ARGS(task, comm),
 
 	TP_STRUCT__entry(
-		__field(	pid_t,	pid)
 		__array(	char, oldcomm,  TASK_COMM_LEN)
 		__array(	char, newcomm,  TASK_COMM_LEN)
 		__field(	short,	oom_score_adj)
 	),
 
 	TP_fast_assign(
-		__entry->pid = task->pid;
 		memcpy(entry->oldcomm, task->comm, TASK_COMM_LEN);
 		strscpy(entry->newcomm, comm, TASK_COMM_LEN);
 		__entry->oom_score_adj = task->signal->oom_score_adj;
 	),
 
-	TP_printk("pid=%d oldcomm=%s newcomm=%s oom_score_adj=%hd",
-		__entry->pid, __entry->oldcomm,
-		__entry->newcomm, __entry->oom_score_adj)
+	TP_printk("oldcomm=%s newcomm=%s oom_score_adj=%hd",
+		  __entry->oldcomm, __entry->newcomm, __entry->oom_score_adj)
 );
 
 /**