Re: linux-next: Tree for Oct 5 (warnings: a. trace; b. mm/migrate)

[Steven Rostedt]

On Tue, 5 Oct 2021 13:46:52 -0700
Randy Dunlap <rdunlap@xxxxxxxxxxxxx> wrote:

> a. randconfig: KCONFIG_SEED=0xBFBEA13C
> ../kernel/trace/trace.c:1712:13: error: 'trace_create_maxlat_file' defined but not used [-Werror=unused-function]
>   static void trace_create_maxlat_file(struct trace_array *tr,

Does this fix it?

-- Steve

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 7896d30d90f7..4520cbab0da5 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1744,16 +1744,15 @@ void latency_fsnotify(struct trace_array *tr)
 	irq_work_queue(&tr->fsnotify_irqwork);
 }
 
-/*
- * (defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)) && \
- *  defined(CONFIG_FSNOTIFY)
- */
-#else
+/* CONFIG_FSNOTIFY else */
+#elif CREATE_MAX_TRACE_FILE
 
 #define trace_create_maxlat_file(tr, d_tracer)				\
 	trace_create_file("tracing_max_latency", 0644, d_tracer,	\
 			  &tr->max_latency, &tracing_max_lat_fops)
 
+#else
+#define trace_create_maxlat_file(tr, d_tracer) do { } while (0)
 #endif
 
 #ifdef CONFIG_TRACER_MAX_TRACE
@@ -9473,9 +9472,7 @@ init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer)
 
 	create_trace_options_dir(tr);
 
-#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)
 	trace_create_maxlat_file(tr, d_tracer);
-#endif
 
 	if (ftrace_create_function_files(tr, d_tracer))
 		MEM_FAIL(1, "Could not allocate function filter files");
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index b7c0f8e160fb..680935949aef 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -679,8 +679,11 @@ void update_max_tr_single(struct trace_array *tr,
 #endif /* CONFIG_TRACER_MAX_TRACE */
 
 #if (defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) \
-	|| defined(CONFIG_OSNOISE_TRACER)) && defined(CONFIG_FSNOTIFY)
-#define LATENCY_FS_NOTIFY
+	|| defined(CONFIG_OSNOISE_TRACER))
+# define CREATE_MAX_TRACE_FILE
+# ifdef CONFIG_FSNOTIFY
+#  define LATENCY_FS_NOTIFY
+# endif
 #endif
 
 #ifdef LATENCY_FS_NOTIFY