executer/exsystem: Warn about sleeps greater than 10 ms

Quick boottime is important, so warn about sleeps greater than 10 ms.

Distribution Linux kernels reach initrd in 350 ms, so excessive delays
should be called out. 10 ms is chosen randomly, but three of such delays
would already make up ten percent of the boottime.

source/components/executer/exsystem.c

@@ -338,6 +338,16 @@ AcpiExSystemDoSleep (
 
     AcpiExExitInterpreter ();
 
+    /*
+     * Warn users about excessive sleep times, so ASL code can be improved to
+     * use polling or similar techniques.
+     */
+    if (HowLongMs > 10)
+    {
+        ACPI_WARNING ((AE_INFO,
+            "Firmware issue: Excessive sleep time (%llu ms > 10 ms) in ACPI Control Method", HowLongUs));
+    }
+
     /*
      * For compatibility with other ACPI implementations and to prevent
      * accidental deep sleeps, limit the sleep time to something reasonable.